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Diagnosis and Treatment of Hypothalamic-Pituitary-Adrenal (HPA) Axis Dysfunction in Patients with Chronic Fatigue Syndrome (CFS) and Fibromyalgia (FM)

  • Holtorf Medical Group (HMG)


There is controversy regarding the incidence and signifi- cance of hypothalamic-pituitary-adrenal (HPA) axis dysfunction in chronic fatigue syndrome (CFS) and fibromyalgia (FM). Studies that utilize central acting stimulation tests, including corticotropin-releasing hormone (CRH), insulin stress testing (IST), d-fenfluramine, ipsapirone, interleukin-6 (IL-6) and metyrapone testing, have demonstrated that HPA axis dysfunction of central origin is present in a majority of these patients. However, ACTH stimulation tests and baseline cortisol testing lack the sensitivity to detect this central dysfunction and have resulted in controversy and confusion regarding the incidence of HPA axis dys- function in these conditions and the appropriateness of treatment. While both CFS and FM patients are shown to have central HPA dysfunction, the dysfunction in CFS is at the pituitary-hypothalamic level while the dysfunction in FM is more related to dysfunction at the hypothalamic and supra-hypothalamic levels. Because treatment with low physiologic doses of cortisol (
Diagnosis and Treatment
of Hypothalamic-Pituitary-Adrenal (HPA)
Axis Dysfunction in Patients
with Chronic Fatigue Syndrome (CFS)
and Fibromyalgia (FM)
Kent Holtorf, MD
ABSTRACT. There is controversy regarding the incidence and signifi-
cance of hypothalamic-pituitary-adrenal (HPA) axis dysfunction in
chronic fatigue syndrome (CFS) and fibromyalgia (FM). Studies that
utilize central acting stimulation tests, including corticotropin-releasing
hormone (CRH), insulin stress testing (IST), d-fenfluramine, ipsapirone,
interleukin-6 (IL-6) and metyrapone testing, have demonstrated that
HPA axis dysfunction of central origin is present in a majority of these
patients. However, ACTH stimulation tests and baseline cortisol testing
lack the sensitivity to detect this central dysfunction and have resulted in
controversy and confusion regarding the incidence of HPA axis dys-
function in these conditions and the appropriateness of treatment. While
both CFS and FM patients are shown to have central HPA dysfunction,
the dysfunction in CFS is at the pituitary-hypothalamic level while the
dysfunction in FM is more related to dysfunction at the hypothalamic
and supra-hypothalamic levels. Because treatment with low physiologic
doses of cortisol (<15 mg) has been shown to be safe and effective and
routine dynamic ACTH testing does not have adequate diagnostic sensi-
Kent Holtorf is Medical Director, Holtorf Medical Group, Inc., Torrance, CA, and
Chief, Medical Advisory Board, Fibromyalgia and Fatigue Centers, Inc., Dallas, TX.
Address correspondence to: Kent Holtorf, MD, Holtorf Medical Group, Inc., 23456
Hawthorne Boulevard, Suite 160, Torrance, CA 90505 (E-mail:
Published papers were identified and reviewed via a computerized literature search
of the PubMed database with associated keywords.
Journal of Chronic Fatigue Syndrome, Vol. 14(3) 2007
Available online at
©2007 by The Haworth Press. All rights reserved.
doi:10.1300/J092v14n03_06 59
tivity, it is reasonable to give a therapeutic trial of physiologic doses of
cortisol to the majority of patients with CFS and FM, especially to those
who have symptoms that are consistent with adrenal dysfunction, have
low blood pressure or have baseline cortisol levels in the low or low-nor-
mal range. doi:10.1300/J092v14n03_06 [Article copies available for a fee
from The Haworth Document Delivery Service: 1-800-HAWORTH. E-mail ad-
dress: <> Website: <http://www.HaworthPress.
com> © 2007 by The Haworth Press. All rights reserved.]
KEYWORDS. HPA axis dysfunction, hypothalamic-pituitary-adrenal
axis, chronic fatigue syndrome, fibromyalgia, CFIDS, cortisol, hydro-
Chronic Fatigue Syndrome (CFS) and fibromyalgia (FM) are dis-
abling conditions that are shown to be present in 0.5-5% of the popula-
tion and often coexist (1-3). Treating CFS and FM patients is often
frustrating for physicians as there is no clear etiology or treatment, and
the use of standard recommended treatments that don’t address the
underlying pathophysiology, including NSAIDs, antidepressants and
muscle relaxants, are largely ineffective and have significant side-ef-
fects (4-7). Reliance on these medications results in a poor prognosis
and is unsatisfying for both patients and physicians (8-18). There is un-
likely a single causative agent or process occurring in these conditions.
The hypothalamic-pituitary dysfunction that is present in the majority
of CFS and FM patients results in HPA axis dysfunction that is often not
detected by standard testing done in a clinical setting, as these tests are
designed to detect primary adrenal insufficiency and have poor sensitiv-
ity for secondary or tertiary adrenal insufficiency (19-58). In addition,
this hypothalamic-pituitary dysfunction results in secondary and/or ter-
tiary hypothyroidism (as well as evidence of thyroid resistance) that is
not detected with standard thyroid testing (27,59-69), and low growth
hormone production that is also not detected by standard testing
(27,60,70-74). There has also been shown to be associated mitochon-
drial dysfunction (75-78), sleep disorder (79-84), immune dysfunction
(85-95), chronic infections (96-105), autonomic dysfunction (106-108),
gastrointestinal dysfunction (109-113) and coagulation dysfunction
(114-119) in these patients.
A multi-faceted treatment approach that addresses the above abnor-
malities, including treatment with hormonal supplementation despite
seemingly normal levels and treatment of the mitochondrial dysfunc-
tion, sleep disorder, chronic infections, immune dysfunction, gastroin-
testinal dysfunction and the coagulation dysfunction is now the
standard of care by experts who specialize in the treatment of CFS and
FM (65,69,78,120-146). There are seemingly contradictory studies re-
garding the incidence of HPA axis dysfunction in these conditions.
However, a clearer understanding of pathophysiology of these condi-
tions demonstrates that the negative results are largely due to a lack of
sensitivity of the testing utilized and the improper use of standard cut-
offs to denote normal function and not because there is an absence of
HPA axis dysfunction.
There are a large number of studies that assess basal cortisol levels in
CFS and FM patients as a primary focus or as part of a subsequent stim-
ulation test. These are of limited value as they fail to assess the function
of the HPA axis during stress and lack sensitivity in detecting central
HPA axis dysfunction. The majority of studies measuring 24-hour urine
cortisol levels in CFS and FM patients have demonstrated significantly
lower values in the CFS/FM patients (22,29,30,32,33,45-49). As with
baseline measures of serum cortisol, twenty-four hour urine cortisol
lacks sensitivity at detecting central HPA axis dysfunction because it
does not necessarily assess the HPA axis dysfunction during stress. Ad-
ditionally, the wide individual variation of 24-hour cortisol excretion in
normal individuals due to varying stress levels over the 24 hours signifi-
cantly decreases sensitivity. Ten studies were identified that assess
24-hour urine cortisol levels in CFS and FM patients with six demon-
strating a significant decrease in 24-hour urine cortisol in CFS/FM pa-
tients and one demonstrating reduced levels that did not reach statistical
significance (22,29,30,32,33,45-49). The majority of studies that mea-
sured 24-hour urine involve very small numbers of patients and con-
trols, limiting the sensitivity, while the largest study to date by Cleare et
al. involving 121 CFS patients and 64 controls demonstrated signifi-
cantly decreased 24-hour urine cortisol levels in CFS patients that
averaged approximately 30% lower than healthy controls (47).
The lack of sensitivity of the 24-hour urinary cortisol levels is dem-
onstrated by the fact that two of the four negative studies also performed
Original Research 61
stimulation tests (IST or IL-6) and both demonstrated HPA axis dys-
function despite having normal or non-significantly reduced 24-hour
urine cortisol levels (32,33).
One of the two remaining negative studies was a small study by Maes
et al. in which 24-hour cortisol levels were measured in patients with
FM, major depression and post traumatic stress disorder (PTSD) com-
pared to normals (49). This study consisted of 14 FM patients and 17
normals. The contradictory findings of this study may be explained by
the fact that it appears that they excluded patients who were on any med-
ications and it also appears that these patients were not previously diag-
nosed with FM prior to the study. This would tend to include only those
with very mild disease and exclude those with moderate or severe
symptoms, who would more likely have been previously diagnosed
with FM and require medications for symptomatic relief.
The second of the two remaining negative studies was by Young et
al. that compared 24-hour urinary cortisol between 22 CFS patients and
24 controls (48). The difference in these results may be explained by
different patient characteristics than the other studies, including the fact
that these patients had the shortest mean duration of symptoms of all the
24-hour urine cortisol studies, being only 2.5 years, compared to the
other studies that had mean durations of 3.6 to 9.7 years.
There are a large number of seemingly contradictory studies that
measure basal cortisol levels or utilize standard dynamic ACTH stimu-
lation tests to evaluate HPA axis function in CFS and FM, which has led
to confusion and controversy as to the incidence of HPA axis dysfunc-
tion in these conditions. One likely contributing cause of the confusion
and controversy is that it has been shown that the plasma cortisol
immunoassays used by the majority of laboratories, institutions and
studies suffer from considerable inaccuracy and variance and can sig-
nificantly overestimate serum cortisol levels when compared to gold
standard assays such as gas-chromatograph/mass spectrometry (GC/
MS) and high performance liquid chromatography (HPLC). This has
led to controversy, a high degree of misdiagnosis and the misclassi-
fication of patients as having normal HPA function despite significant
dysfunction or severely underestimating the severity of the dysfunction
For instance, Cohen et al. compared three commonly used cortisol
immunoassays (Bayer Advia Centaur, Abbott TDx and DPC Immulite
2000) and HPLC to determine serum cortisol levels and found a huge
variation in results with concordance in only 44% of patients. The
immunoassays were shown to overestimate the serum cortisol levels by
an average of 70% (35%, 79%, and 95%, respectively, for each assay)
without appropriate adjustment of the reference ranges by the assay
manufacturers. This resulted in the misclassification of 44-56% of pa-
tients depending on the assay used. The Centaur assay produced results
that were over 480% of that of the HPLC standard, the TDx assay pro-
duced results that were up to 590% of the standard and the Immulite as-
say produced results that were 770% of the standard (147).
De Brabandere et al. evaluated the performance of three cortisol
immunoassays commonly used by laboratories in the U.S. and Europe
(Diagnostic Products Corp (DPC), Amerlex and Baxter Diagnostics)
(149). They measured cortisol levels in 15 patient samples and 10 com-
mercially prepared control serum standards in duplicate and compared
the results with those obtained via the gold-standard GC/MS. The mea-
sured cortisol results on the commercially prepared control samples
showed that the assays averaged only 11% higher than when measured
via the GC/MS. However, the results on the patient samples demonstrated
a severe inaccuracy of these assays commonly used in commercial labo-
ratories. The mean deviation of the reported cortisol concentrations that
were below 13 ng/ml (370 nmol/l) was +21%, +91%, and +83% for
each assays, respectively. These differences were not reflected in the re-
spective kit reference ranges. For instance, the upper reference range for
the Amerlex assay is only 12% higher than the upper reference range of
the DPC assay despite averaging over 40% higher on the same speci-
mens. Baxter quotes an upper reference range that is significantly lower
than the Baxter assay (552 nmol/l vs. 690 nmol/l) despite having the
strongest positive overall bias. The lower limit for the Amerlex assay is
only 9% greater than the DPC assay (152 nmol/l vs. 158 nmol/l) despite
averaging over 60% higher on the same specimens. These studies dem-
onstrate that a seemingly normal baseline or stimulated cortisol level re-
ported by a laboratory cannot be relied upon to accurately rule out
significant hypocortisolism.
Further confounding results is the fact that CFS and FM patients are a
very heterogeneous group in terms of illness severity and duration and
associated psychiatric comorbidities, which likely influence HPA dys-
function. In addition, there is the significant normal variation in cortisol
levels in normal individuals. A more important fact is, however, that a
multitude of studies have demonstrated the HPA axis dysfunction in
these conditions is central (hypothalamic or pituitary), not a primary ad-
renal insufficiency. Consequently, it is of no surprise that these studies
appear to have inconsistent results because baseline cortisol levels and
ACTH dynamic testing have very low sensitivities in detecting central
Original Research 63
HPA axis dysfunction and fail to diagnose the majority of patients with
known significant central HPA axis dysfunction (29,31,35-44). Be-
cause a normal result with such testing does not rule out significant dys-
function, it is not a recommended means of detecting this abnormality.
Low dose (1 μg ACTH) stimulation may be slightly more sensitive than
conventional (250 μg ACTH) testing, but it still suffers from very poor
sensitivity and misses approximately 50% of individuals with estab-
lished central hypoadrenalism determined by IST, d-fenfluramine,
ipsapirone, CRH stimulation or metyrapone testing (35-41,44,152).
Studies that use appropriate testing for individuals with secondary or
tertiary hypoadrenalism, including IST, metyrapone testing and stimu-
lation testing using CRH, IL-6 and d-fenfluramine, have consistently
demonstrated significant HPA axis dysfunction in CFS and FM pa-
tients. Of the 16 studies identified that used such testing, all but one of
these studies demonstrated HPA axis dysfunction with abnormal
ACTH and/or cortisol secretion (19-33,41).
Demitrack et al. studied the functional integrity of the various com-
ponents of the HPA axis in 30 patients with CFS and 72 normals with an
average duration of illness of 7.2 ±1.0 years. They performed CRH (bo-
vine 1 μg/kg) stimulation testing and graded ACTH stimulation testing.
They also compared the levels of evening serum free and total cortisol,
cortisol binding globulin (CBG) and corticotropin releasing hormone
(CRH) in the cerebrospinal fluid and measured 24-hour urinary cortisol
levels (19).
They found significantly lower evening cortisol levels in CFS pa-
tients vs. controls (3.2 μg/ml ±0.3 vs. 5.3 ±0.73) and 24-hour urinary
free cortisol excretions that were 40% lower in the CFS patients (122.7
nmol/l vs. 203 nmol/l). Interestingly, the level of cortisol binding globu-
lin CBG was also significantly higher in the CFS patients making the
free cortisol index almost 70% lower in these patients (2.9 vs. 8.9). This
elevated CBG is significant because it results in an overestimation of
bioavailable and free cortisol levels, and if confirmed, it may be further
contributing to the lack of sensitivity of both basal and dynamic testing
by overestimating cortisol levels in these patients because most of the
studies have utilized total cortisol levels when comparing CFS and FM
patients to normals. This potential of overestimation of serum cortisol
levels would be additive to the overestimation of actual cortisol levels
by commonly used immunoassays discussed earlier (147,149).
This study found a significant attenuated net integrated ACTH re-
sponse to CRH (128 ±26.4 vs. 225 ±34.5) (p < 0.04) demonstrating
central HPA axis dysfunction. With ACTH stimulation testing, there
was an initial increased sensitivity to ACTH with a subsequent reduced
maximal response. Although this cortisol response to ACTH was clearly
abnormal for all of the patients with CFS in this study, the dose response
curve varied. There was an initial exaggerated response followed by an
abnormally blunted response, which is not the case for patients with
simple primary or secondary adrenocortical insufficiency and demon-
strates hypothalamic involvement in the HPA axis dysfunction in these
patients (19).
Scott et al. (1998) performed CRH (bovine 100 μg) stimulation tests
on 14 CFS patients with an average illness duration of 4.8 ±0.6 years
(range 1.5-10 years) as compared to 14 controls. There were lower basal
ACTH and cortisol levels in the CFS patients, but it did not reach statis-
tical significance. The delta-ACTH response in the CFS group (21.4 ±
4.3 ng/l) was significantly lower than that in the controls (51.9 ±8.5) (p
< 0.005). The delta-cortisol levels were also similarly attenuated in the
CFS group (197.7 ±21.6 nmol/l) vs. the healthy controls (310.5 ±21.6
nmol/l), demonstrating central HPA axis dysfunction in these patients
Scott et al. (1999) again evaluated the HPA axis in CFS patients by
performing CRH (bovine 100 μg) stimulation tests on 13 CFS patients
as compared to 13 controls. Patients had a mean duration of illness of
5.0 years. This study found that 8 out of 13 CFS patients had lower stim-
ulated ACTH levels than the lowest ACTH response in the normal con-
trols, being 21.0 ±4.5 ng/l in the CFS patients as compared to 57.8 ±11
ng/l (p = .005) in normal controls. The delta-cortisol response in 9 of the
12 CFS patients was lower than the lowest delta-cortisol in the control
group (157.6 ±40.7 nmol/l in the CFS group compared to 303.5 ±20.9
nmol/l in the control group [p = 0.01]), again demonstrating central
HPA axis dysfunction in CFS patients (21).
Cleare et al. (2001) performed CRH (human 1 μg/kg), IST and d-fen-
fluramine stimulation testing in 37 medication free CFS patients.
Patients had a mean duration of illness of only three years. Thirty-two
patients were treated with low dose (either 5 mg or 10 mg cortisol per
day). With human CRH stimulation testing, there were similar ACTH
responses between groups with AUC cortisol values being reduced in
Original Research 65
CFS patients as compared to controls (206 ±213 nmol/l-h vs. 313 ±257
nmol/l-h [p = 0.069]). When ACTH was controlled for, the CFS patients
had a significantly reduced release of cortisol (p = 0.016). The differ-
ence in the abnormality seen in this study as compared to Demitrack et
al., Scott et al. (1998) and Scott et al. (1999) could be due to different
patient characteristics. The average duration of illness in this study was
only three years, while the average duration of illness in the Demitrack
et al. and the Scott et al. studies were 7.2, 5 and 4.8 years, respectively.
In addition, human CRH was used at 1 μg/kg as compared to bovine
CRH, which is more potent and has a longer half life, being used in the
Demetrik and Scott et al. studies. Scott et al. used human CRH at a
higher average dose of 100 μg, as well. Interestingly, the patients who
responded to treatment with clinical improvement had a normalization
of the previously blunted cortisol response to CRH, while those who did
not clinically respond had no significant change in the endocrine
parameters before and after treatment, demonstrating a lack of adrenal
suppression and a potential improvement in HPA axis function with
physiologic doses of cortisol (22).
With d-fenfluramine stimulation testing, there was again a trend for
lower cortisol response (p = 0.077) without a significant difference in
ACTH levels. When ACTH responses were controlled for, cortisol re-
sponses were significantly reduced (p = 0.033). There was no signifi-
cant difference in ACTH or cortisol responses between groups with IST
assessment, but there was significantly reduced urine 24-hour cortisol
levels in CFS patients vs. controls (p = 0.025) (22).
Inder et al. compared 24-hour urinary cortisol levels and performed
CRH (bovine 1 μg/kg) stimulation testing on 12 CFS patients and 11
controls. They found no significant difference in 24 hour urinary cortisol
levels, basal ACTH, basal cortisol levels, stimulated ACTH or stimu-
lated cortisol levels. The illness duration was not stated. This difference
may be explained by the heterogeneity of this population and the small
study size. The study size would require a 40% difference between
groups to distinguish a difference (23).
Gaab et al. performed IST on 18 CFS patients with an average illness
duration of 5.6 years (range 1.4-14 years) and 17 controls. They found a
significantly blunted ACTH response to IST that was 40% less in the
CFS group compared to controls, demonstrating central HPA axis dys-
function in these patients. Interestingly, they also performed two proce-
dures mimicking real-life stressors and also found significantly lower
ACTH responses in the CFS patients as compared to controls, demon-
strating central HPA axis dysfunction (24).
Bearn et al. performed IST and d-fenfluramine stimulation testing on
nine CFS patients and ten normal controls. The average duration of ill-
ness was 5.7 years with a range of 1-15 years. All but one had signifi-
cant myalgia and were not on medication for 12 weeks prior to study.
There was a delayed and attenuated ACTH and cortisol response to IST
that was consistent with hypothalamic-pituitary dysfunction but due to
the small sample size, it did not reach statistical significance (25).
There was a significantly increased ACTH response with d-fenflura-
mine stimulation with a decreased cortisol response that also did not
reach statistical significance due to the sample size. This is consistent
with hypothalamic dominant dysfunction with a centrally inhibited ad-
renal response to ACTH. A hypothalamic dysfunction with a primary
adrenal dysfunction is also possible, but unlikely, considering normal
adrenal response to ACTH under different study conditions. These pa-
tients’ ACTH and cortisol response was more indicative of FM patients
(discussed below) and demonstrates a more hypothalamic/supra-hypo-
thalamic dominant dysfunction that is seen in the FM patients as com-
pared to the hypothalamic/pituitary dysfunction typically seen in CFS
patients. The authors did not state if any of the patients also met the cri-
teria for FM, but all but one had significant myalgia, so it is likely that
they did have FM, thus explaining the results (25).
Dinan et al. (1997) demonstrated a blunted release of ACTH in re-
sponse to ipsapirone, a serotonin agonist, in 14 CFS patients vs. 14 con-
trols (4.4 ±0.6 ng/l vs 14.6 ±1.6 ng/l), demonstrating central HPA axis
dysfunction in these patients (26).
Riedel et al. (1998) injected CRH (bovine 100 μg) along with a simul-
taneous injection of TRH, GHRH and LHRH in 16 FM patients and 17
controls. They found elevated basal levels of ACTH and cortisol and an
exaggerated ACTH response with no difference in stimulated cortisol
levels, demonstrating a hyporesponsive adrenal response to ACTH.
This is most consistent with a hypothalamic or a supra-hypothalamic
dominant dysfunction rather than a primary adrenal insufficiency. They
also found significantly elevated prolactin levels on stimulation with
significantly reduced TSH secretion, free T3 production and growth
Original Research 67
hormone secretion, all demonstrating hypothalamic-pituitary dysfunc-
tion (27).
Griep et al. (1993) performed CRH (human 100 μg) stimulation test-
ing and IST on 10 FM patients and 10 controls. They also found a statis-
tically significant enhanced ACTH response and a relative adrenal
hypo-responsiveness in the FM patients as compared to controls with
both the IST and CRH testing, indicating a tertiary (hypothalamic or su-
pra-hypothalamic level) hypoadrenalism (28).
Griep et al. (1998) compared the HPA axis function in 40 FM pa-
tients with an average illness duration of 10.7 ±7.2 years, 28 patients
with chronic low back pain and 14 controls. They used a combination of
tests that included CRH (human 100 μg) stimulation testing, very low
dose (0.025 μg/kg) and low dose (0.1 μg/kg) ACTH stimulation tests
and 24-hour urinary cortisol evaluations. This study also showed a sig-
nificantly abnormal HPA axis in FM patients after CRH stimulation
with an ACTH hyper-responsiveness and a relative adrenal hypo-re-
sponsiveness, indicating a tertiary (hypothalamic or supra-hypotha-
lamic level) hypoadrenalism (29).
There was also significantly decreased 24-hour urine cortisol levels
in the FM patients compared to the controls, but there was no difference
in the evoked cortisol levels with either the very low dose or the low
dose ACTH simulation tests between the three groups, indicating that
there is not a primary adrenal dysfunction. This study also further dem-
onstrates and supports other studies that show that ACTH stimulation
testing is an insensitive means of detecting central HPA axis dysfunc-
tion and is, therefore, not a recommended method of evaluation in these
patients (29,31,36-39,152).
Crofford et al. performed CRH (bovine 1 μg/kg) testing and 24-hour
urinary free cortisol levels in 12 FM patients and 12 controls. The FM
patients had an average duration of illness of 6.2 ±3.1 years. This study
found a non-statistically significant exaggerated ACTH response to
CRH with a statistically significant decrease in net cortisol response
(p < 0.02), demonstrating a hypothalamic dominant dysfunction of the
HPA axis of FM patients. They also found a statistically significant de-
crease in 24-hour urinary free cortisol levels (p < 0.002) (30).
Calis et al. performed metyrapone testing and 1 μg ACTH stimula-
tion tests on 22 FM patients and 15 matched controls. After metyrapone
administration, 95% of FM patients had lower 11-deoxy-cortisol than
the lowest level in the healthy controls, while only 45% of FM patients
had low cortisol responses to the ACTH simulation test (31). This dem-
onstrates central HPA axis dysfunction in these patients, but ACTH
stimulation testing will miss approximately half the individuals with
significant dysfunction and is not a recommended means of evaluating
the HPA axis in these patients (29,31,36-39,152).
Kirnap et al. performed IST as well as 1 μg and standard ACTH stim-
ulation testing on 16 FM patients and 16 controls. They found signifi-
cant reduced basal cortisol levels in the FM group (p < 0.0001) as well
as significantly reduced responses to all three stimulation tests (p <
0.0001), demonstrating significant central HPA axis dysfunction in
these patients (ACTH levels were not measured). They also found that
if the standard cutoffs were used with the ACTH simulation test, most
of the patients would have been misdiagnosed as normal (40).
Adler et al. performed stepped hypoglycemic hyperinsulinemic clamp
studies, performed ACTH infusions and evaluated 24-hour urinary free
cortisol levels in 15 FM patients and 13 controls. The average duration
of illness was 9 ±8 years. Baseline 24-hour urinary free cortisol levels
were not significantly different between the two groups, but basal
ACTH levels were significantly lower in FM patients (2.8 ±1.7 pmol/l)
as compared to the control group (5.0 ±2.9 pmol/l). The ACTH levels
in response to hypoglycemia were significantly reduced in the FM
group, with an average integrated response being 68% of that of the
control group. Baseline hypoglycemic stimulated and ACTH stimu-
lated cortisol levels were not significantly different. These results of a
diminished ACTH response are in contrast to the above studies demon-
strating an exaggerated ACTH response in FM patients and more simi-
lar to the results involving CFS patients. There is significant overlap in
those diagnosed with FM and CFS and this may have been a factor in
this study. Additionally, this group had a much longer duration of ill-
ness than the FM patients in the previously discussed studies and differ-
ent methodologies could also explain the differences (33).
Torpy et al. performed 24-hour urine cortisol levels and administered
IL-6 stimulation tests to 13 FM patients and 8 controls. There was a
trend to lower 24-hour urine cortisol levels in FM patients vs. controls
(40.7 ±5 ng/24-hours vs. 57.0 ±9.9 ng/24-hours) although it did not
reach statistical significance. They found no significant difference in
peak cortisol or ACTH levels between the two groups, but the FM group
was shown to have a significant delay in the ACTH response, with peak
levels not occurring until 96 ±6 minutes vs. 68.6 ±10.3 minutes in the
control group. This delayed ACTH response with a trend to lowered
24-hour urine cortisol levels supports a dysfunction at or above the hy-
Original Research 69
pothalamic level. This delayed ACTH response as compared to the ex-
aggerated ACTH response to CRH in FM probably reflects differences
in the principle site of action of these agents and supports HPA axis
dysfunction at or above the hypothalamic level (32).
In a randomized crossover trial, Cleare et al. 1999 treated 32 CFS pa-
tients with a mean duration of illness of 3 years (range 2.3-3.75 years)
with low dose cortisol (5-10 mg/day) and placebo for one month in a
randomly assigned order. This study found significant improvements in
fatigue and disability in those treated with low dose cortisol but not with
placebo (p = 0.009). Twenty-eight percent of the patients improved to
normal levels with treatment, and follow-up IST demonstrated that
there was no suppression of endogenous adrenal function with treat-
ment. In fact, those who responded to treatment had an improvement in
HPA axis function via CRH stimulation testing, demonstrating the ef-
fectiveness and appropriateness of this treatment (22,146).
Blockmans et al. performed a 6-month randomized, placebo-con-
trolled, double-blind, crossover study of 80 patients with CFS using a
combination of 5 mg cortisol and 50 μg of fludrocortisone. Patients had
an average duration of illness of only 2.5 years (1.3-5). There was sig-
nificant improvement in fatigue scores with treatment as measured with
an Abbreviated Fatigue Questionnaire (p = 0.004), but there was a sig-
nificant placebo response so it was not significantly different from pla-
cebo. There was no difference in fatigue scores as measured by a visual
analog scale. There was significant improvement in the Mental Factor
of the Short Form Health Survey compared to placebo and also in the
Physical Factor but not compared to placebo. Depression scores im-
proved with treatment vs. placebo. ACTH simulation tests were per-
formed at 0, 3, and 6 months. The baseline ACTH stimulation tests were
normal and none of the patients had any evidence of adrenal suppres-
sion with treatment (153).
The less impressive response in this study as compared to the Cleare
study is potentially explained by different patient characteristics. These
patients had a much shorter duration of illness and were recruited from
different patient populations. The Cleare study recruited patients from
clinics that specialize in CFS in England and Blockmans et al. recruited
patients from a tertiary care university hospital in Belgium, and they ap-
peared to have excluded those with ulcers, hypertension, glaucoma or
diabetes but did not exclude those with fatigue related illnesses. These
patients appeared likely to be an especially heterogeneous group with a
multitude of disease processes.
Mckenzie et al. performed a randomized, placebo-controlled, dou-
ble-blind 12-week therapeutic trial with 25-35 mg of cortisol to 30 CFS
patients and 35 controls. Patients met the more rigorous 1988 criteria
for CFS and were assessed with a daily wellness scale for 12 weeks. The
study found that 66.7% of patients improved with treatment, with most
patients reporting a modest but significant difference vs. placebo as
measured by at least a 5, 10 or 15 point improvement. A five or more
point improvement was seen in 53% of the cortisol treated patients vs.
29% receiving placebo (p = .04), a 10 point improvement was seen in
33% of the cortisol treated patients vs. 14% of controls (p = .07) and a
15 point improvement was seen in 20% of cortisol treated patients vs.
6% of controls (p = .08) (154).
Three patients in the treatment group withdrew due to ineffectiveness
and four withdrew from the placebo treatment (three due to ineffective-
ness and one due to a rash). Five of the cortisol treated patients did not
have pretreatment wellness scores so they could not be evaluated. There
was no significant correlation between response and the pretreatment
basal or ACTH stimulated cortisol levels. Five patients in the treatment
group had a depressed cortisol response in the post treatment ACTH
simulation testing. However, the doses used in this study are considered
by many researchers and clinicians that specialize in CFS/FM to be in-
appropriately high for treatment of this condition (54,120,124,125,136,
155-162) and significantly higher than the studies that demonstrate a
lack of adrenal suppression with lower doses of 5-15 mg/day (22,120,
Teitelbaum et al. performed a randomized, double-blind, placebo
controlled, intent to treat study on 72 FM (69 also met CFS criteria) pa-
tients (38 active and 34 placebo) that documents the effectiveness of an
integrative treatment approach to CFS and FM that includes low dose
cortisol (7.5-20 mg/day) (120). The patients underwent an integrative
multi-system treatment protocol based on an algorithm that took into
account laboratory tests as well as signs and symptoms. Potential treat-
ments included antidepressants, levothyroxin, cortisol, fludrocortisone,
DHEA, testosterone and antimicrobial treatments. Cortisol was admin-
istered if there was a baseline cortisol level = 12; the ACTH stimulated
cortisol increase was < 7 at 30 minutes, < 11 at 60 minutes or the 60
minute cortisol was < 28; the HgbA1C was < 5.1; or if patients had three
significant symptoms consistent with adrenal dysfunction. Cortisol was
Original Research 71
given to 29 of the 38 patients at some time during the 3 month study.
Overall, patients had significant improvements vs. placebo in visual
analog scores (p < 0.0002), the Fibromyalgia Impact Questionnaire
(p < 0.0005), the tender point index (p < 0.0001) and overall response
(p < 0.0001). No patients were found to have any adrenal suppression
with post-treatment ACTH simulation tests. While this study does not
separate out cortisol’s overall effect, it provides the basis for demon-
strating that an integrative multi-system treatment approach that in-
cludes low dose cortisol is highly safe, effective and appropriate in the
treatment of these conditions. This integrative approach is now consid-
ered by many who specialize in the treatment of CFS/FM to be the cur-
rent basic standard of care (65,69,120-146) and has served as a building
block for more advanced therapies and algorithms. Interestingly, a
sub-analysis demonstrated that antidepressants had no significant bene-
ficial effect on the patients’ outcome scores (p < .0001) (120).
Currently, our center has tracked over 500 consecutive patients that
met the CDC criteria for CFS and/or the American College of Rheum-
atology criteria for FM (240 met criteria for CFS, 14 met the criteria for
FM and 259 met criteria for both). The computerized tracking system
consists of the tracking of the patients’ average overall energy level and
sense of well-being (SOWB) on each visit as well as the frequency and
severity of 10 symptoms that includes fatigue, muscle pain, stiffness,
cognitive function, headaches, insomnia, unrestful sleep, gastrointesti-
nal dysfunction and sore throat. Before each visit, patients rated their
energy and sense of well being on a scale of 1-10 (1 being low and 10
being high) and their individual symptom frequency and severity on a
scale of 1-10 (10 being constant and 1 being rare for frequency and 10
being severe and 1 being mild for severity). Patients had seen on aver-
age 7.2 different physicians for treatment of their CFS and/or FM with-
out significant improvement prior to being seen at our center. Patients
were treated based on a multi-system integrative treatment algorithm
that incorporates therapies based on the most recent understanding of
the pathophysiology of these conditions (due to its complexity, a de-
scription of the algorithm is beyond the scope of this review). The treat-
ment algorithm did include low dose cortisol after the second visit if
symptoms were consistent with adrenal dysfunction based on 24 symp-
toms and/or having low blood pressure and/or having a baseline cortisol
level in the low or low-normal range. If patients met the protocol crite-
ria, they were given a therapeutic trial of 5-15 mg of timed-released
cortisol per day. Patients were also given fludrocortisone if they had
signs of neurally mediated hypotension.
Analysis revealed (prepublication ongoing data collection) that 94%
of patients had overall improvement by the 4th visit with 75% noting
significant overall improvement and 62% reporting substantial overall
improvement. The majority of patients continued to improve in subse-
quent visits. The average energy levels and average SOWB increased
significantly. The average energy level more than doubled by the 4th
visit, going from an average of 2.98 at baseline to 6.39 at the 4th visit
and then to 6.77 and 7.67 at the 7th and 9th visits, respectively. The av-
erage SOWB also more than doubled by the fourth visit, increasing
from a baseline average of 3.03 then increasing to 6.29, 7.45, and 6.83
on the 4th, 7th, and 9th visit, respectively. There were no significant
side-effects from low dose cortisol in these closely monitored patients
Subsequently, over 40 physicians were trained to utilize a more sim-
plified treatment algorithm in 17 centers across the country. In this
multi-center study, over 4000 consecutive patients diagnosed with CFS
and/or FM were treated with this simplified algorithm and tracked via
the same computerized patient assessment system. This prepublication
ongoing data collection demonstrated that 85% of patients improved by
the 4th visit, with 56% and 40% reporting significant and substantial
improvement, respectively, by the 4th visit. This increased to 62% and
46% by the 7th visit (137).
While these two studies are not placebo controlled and do not allow
the evaluation of cortisol as a sole treatment of CFS/FM, as cortisol was
only a part of the multi-system treatment protocol that included numer-
ous therapeutic interventions, cortisol supplementation was shown to be
a beneficial and safe therapeutic intervention with little or no risk as part
of a multi-system integrative treatment protocol. It is extremely un-
likely that such dramatic improvements were due to a placebo effect be-
cause these patients had been typically seen by numerous physicians
without improvement and such patients have been shown to have little
placebo responses (163).
Because physiologic doses of cortisol (<15 mg) do not increase lev-
els beyond normal levels, it is exceedingly safe and is not associated
with adverse effects associated with pharmacological doses of corti-
costeroids, including adrenal suppression, bone loss and immune sup-
pression (22,54,120,136,137,146,153,155-157,162,164-176). A review
Original Research 73
by Jefferies of 1000 patient-years of treatment with physiological doses
of cortisol found that the only undesirable side effect was acid indiges-
tion and skin rashes due to allergies to the tablets’ fillers in a few
patients (155).
As opposed to pharmacological doses of corticosteroids, physiologi-
cal doses (< 15 mg) of cortisol have been shown not to cause adrenal
suppression (22,120,146,153,156,162) and have been shown to actually
improve HPA axis function (22). This is counterintuitive to what physi-
cians are taught and have found with higher pharmacological doses of
glucocorticoids. Also, physiologic doses of cortisol have been shown to
improve cellular and hormonal immunity, including natural killer cell
activity (155,157,164-171,177), which has been found to be a consis-
tent abnormality in CFS patients (85-88). This is also counter-intuitive
to physicians because of the well-known immune suppression that is
seen with pharmacological doses of corticosteroids.
The longest randomized placebo controlled studies (over 2 years)
that assessed bone loss with the use of low dose corticosteroids
(= equivalent to 40 mg of cortisol) have demonstrated that there is no
significant increase in bone loss vs. placebo with such treatment
(172-176). The fact that these studies, while considered low dose, were
considerably higher than the recommend doses for CFS and FM pa-
tients, demonstrates that using cortisol supplementation at doses less
than 15 mg would not have any adverse effects on bone loss.
Low physiologic doses of cortisol (<15 mg) carry little risk and have
a risk/benefit ratio that compares favorably to treatments that are con-
sidered standard therapies for CFS and FM, including antidepressants,
NSAIDS, muscle relaxants and low-dose narcotics. For instance, there
is considerable anecdotal evidence supporting the use of SSRI’s in CFS
and FM, and most physicians feel they are significantly beneficial in
these patients. However, randomized blinded placebo controlled trials
have consistently shown little benefit, with the majority of patients not-
ing significant side effects with up to a third of patients having to dis-
continue treatment due to side effects (4,5). The newer dual acting
antidepressants such as duloxetine have been shown to be beneficial in
FM but suffer from poor tolerability (6,7). A randomized controlled
trial demonstrated that duloxetine was of benefit in women with FM but
not in men. In addition, 90% of patients had significant side-effects in
the treatment group and 44% had to discontinue treatment due to
moderate or severe side-effects (6,7).
In contrast, side effects are very rare and significant side effects are
essentially non-existent with physiologic doses of cortisol. An even
more compelling argument can be made when the considerable risks,
that include death, of other common treatments for CFS and FM, in-
cluding NSAIDS, muscle relaxants and low dose narcotics, are com-
pared to the negligible risk of physiologic doses of cortisol.
There is ample evidence that there is HPA axis dysfunction of central
origin in CFS and FM but the exact level or levels of dysfunction are
less clear. The data are consistent with mixed hypothalamic-pituitary
dysfunction in CFS and FM with CFS having more pituitary dominant
dysfunction while FM patients have more hypothalamic or supra-hypo-
thalamic dominant dysfunction. This is consistent with the fact that the
hypothalamus has significant pain modulating properties and hypotha-
lamic dysfunction has been shown to increase pain sensation (178).
The HPA axis is an incredibly complex group of specialized neuronal
tissue, with the hypothalamus being the most complex part of the CNS.
The hypothalamus consists of somewhat arbitrarily defined regions and
nuclei that include the pariventricular, arcuate, suprachiasmatic, ante-
rior, ventromedial, dorsomedial, posterior and supraoptic nuclei with
extensive interaction with different afferent and efferent pathways from
the thalamus, basal ganglia, cerebral cortex, reticular formation and
visceral centers of the brainstem. The reticular formation and visceral
centers of the brainstem connect with the hypothalamus through the
mammillary peduncle and the dorsal longitudinal fasciculus. There is
also significant input via locus ceruleus, vagal nuclei, periaqueductal
gray and nuclei of the solitary tract and from the piriform cortex and
amygdala, olfactory nuclei and the hippocampus. While the studies
clearly support HPA dysfunction at the pituitary and hypothalamic
levels, it is not surprising that the precise level and mechanism is
Potential mechanisms occurring in CFS include pituitary dysfunc-
tion with hyporesponsive pituitary corticotrophs, enhanced negative
feedback and/or deficient hypothalamic secretion of CRH. FM patients
have more dysfunction at the hypothalamic level or have abnormal hy-
pothalamic input along with hyporesponsive adrenals to ACTH. There
is convincing evidence of central regulation of adrenal sensitivity to
ACTH (179). Interestingly, depressed patients are characterized by
hyperactivity of all components of the HPA axis, including increased
sensitivity to ACTH by the adrenals and increased CRH mRNA expres-
Original Research 75
sion, with resultant hyercortisolism. Given the complexity of neuronal
interaction in this system, it is unlikely that the precise nature of HPA
axis dysfunction in CFS/FM patients will be elucidated in the near fu-
ture. This certainly does not mean these patients should not be treated
until such understanding is complete.
There is a complex interaction of HPA axis dysfunction in these pa-
tients, and it is becoming clear that the majority of patients with CFS
and FM suffer from clinically significant adrenocortical dysfunction.
Current methods of testing are very poor at assessing the area of dys-
function in these complex interactions, but despite this, all studies uti-
lizing IST, CRH and/or metyrapone testing have shown abnormal
results in these patients. Studies that utilize 24-hour urinary cortisol lev-
els have consistently shown HPA axis dysfunction with only a few stud-
ies showing normal levels in CFS and FM patients. On the whole,
ACTH stimulation testing has shown to be abnormal in about 50% of
CFS/FM patients. This would be the expected percentage if 100% of the
patients had HPA axis dysfunction of central origin, as this test suffers
from very poor sensitivity for central HPA axis dysfunction and would
be expected to miss approximately 50% of these patients. In addition,
the inaccuracy of the most commonly used cortisol assay further con-
founds results. The ACTH stimulation test has clearly been shown to
lack sufficient sensitivity to differentiate CFS and FM patients with
HPA axis dysfunction from those with normal function. A normal result
cannot be used with any confidence in these patients to rule-out signifi-
cant dysfunction; thus, it cannot be recommended as a useful test to
guide treatment in these patients. The more central acting stimulation
tests are also not recommended for routine clinical use because interpre-
tation is problematic, they are burdensome and expensive and carry
significantly more risk than the most appropriate treatment, a therapeu-
tic trial of physiological doses of cortisol.
Physiologic replacement of cortisol at doses of 5-15 mg/day have
been shown to be safe, with little or no associated risk, and have the po-
tential for significant clinical benefit. Cortisol treatment carries signifi-
cantly less risk and a greater potential for benefit than treatments
considered to be the standard of care in the treatment of CFS/FM, in-
cluding antidepressants, muscle relaxants and narcotics. The current
evidence supports the use of physiologic doses of cortisol as an appro-
priate component of a multi-system treatment protocol for CFS and FM,
and a therapeutic trial of cortisol should be considered in the majority of
these patients, especially those with signs or symptoms consistent with
adrenal dysfunction, low blood pressure and/or serum levels that are
low or in the low normal range.
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... HPA axis dysfunction is also present in the majority of fibromyalgia patients (75)(76)(77). Various mechanisms have been suggested, including depressed secretion of CRH by the hypothalamus, a deficiency of CRH receptors on the pituitary, and adrenal atrophy due to chronic under-stimulation by reduced ACTH levels (78). ...
... Dysfunctions of the HPT axis have long been suspected to play a role in ME/CFS (77,(131)(132)(133)(134) and fibromyalgia (135)(136)(137)(138)(139)(140). A recent study showed that ME/CFS patients had similar TSH levels as controls, but lower Free T3, Total T4, and Total T3, which the authors suggest resembles NTIS (141)-the typical feature of critically ill patients in ICUs described above. ...
... Anomalies in thyroid hormone function: Numerous clinical practitioners and researchers believe that anomalies in thyroid hormone function-including changes in the conversion of thyroid hormones, a resistance of thyroid hormone receptors at cellular level, etc. -contribute to ME/CFS and fibromyalgia (133)(134)(135)(136)(137)(138)(139)(140)(141). Indeed, practitioners have written about their successes in treating ME/CFS patients with thyroid hormone supplements (42,77,188,(190)(191)(192)(193)(194); and patients have published books on their experiences (195)(196)(197). Our hypothesis complements this reasoning: we propose that both the central and peripheral mechanisms altering thyroid hormone function during critical illness (c.f. ...
Full-text available
Here the hypothesis is advanced that maladaptive mechanisms that prevent recovery in some intensive care unit (ICU) patients may also underlie Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). Specifically, these mechanisms are: (a) suppression of the pituitary gland's pulsatile secretion of tropic hormones, and (b) a “vicious circle” between inflammation, oxidative and nitrosative stress (O&NS), and low thyroid hormone function . This hypothesis should be investigated through collaborative research projects.
... It also aligns with a recent hypothesis relating many of the symptoms in severe ME/CFS to impaired pituitary function (111). Further support for this proposal is provided by the many previous ME/CFS studies that have documented dysfunctions in the hypothalamic-pituitary-somatotropic (HPS) axis (112)(113)(114), the HPT axis (115)(116)(117)(118)(119)(120), and the HPA axis (121-136)-notably associated with inflammation and oxidative & nitrosative stress (O&NS) (137)(138)(139)(140). Strikingly, models relating the persistence of a suppressed HPA axis in ME/CFS to a change in central GRs concentrations resemble the explanations provided for pituitary suppression in critical illness (141)(142)(143)(144)(145)(146). Moreover, suppression of ACTH release would explain why in a small study ME/CFS patients were found to have 50% smaller adrenals than controls (147), resembling adrenal atrophy in prolonged critical illness. ...
Full-text available
We propose an initial explanation for how myalgic encephalomyelitis / chronic fatigue syndrome (ME/CFS) could originate and perpetuate by drawing on findings from critical illness research. Specifically, we combine emerging findings regarding (a) hypoperfusion and endotheliopathy, and (b) intestinal injury in these illnesses with our previously published hypothesis about the role of (c) pituitary suppression, and (d) low thyroid hormone function associated with redox imbalance in ME/CFS. Moreover, we describe interlinkages between these pathophysiological mechanisms as well as “vicious cycles” involving cytokines and inflammation that may contribute to explain the chronic nature of these illnesses. This paper summarizes and expands on our previous publications about the relevance of findings from critical illness for ME/CFS. New knowledge on diagnostics, prognostics and treatment strategies could be gained through active collaboration between critical illness and ME/CFS researchers, which could lead to improved outcomes for both conditions.
... Currently, there is controversy concerning whether the HPA axis plays a role in the genesis of fatigue symptoms in general [133]. One study reported detectable dysfunction in CFS/ME patients; the authors proposed that administration of cortisol at physiologic levels may be tried as a putative therapy for CFS/ME where there is evidence of adrenal dysfunction [134]. Another report corroborated these findings and discussed that low cortisol levels are more likely to be present in women than in men, that a multidimensional etiological model for CFS/ME is likely, that cognitive-behavioral therapy may be useful in addressing the deficiency in cortisol levels, and finally that further research is needed to fully understand the involvement of HPA axis dysfunction in CFS/ME [135]. ...
Full-text available
Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME) and Cancer-Related Fatigue (CRF) are syndromes with considerable overlap with respect to symptoms. There have been many studies that have compared the two conditions, and some of this research suggests that the etiologies of the conditions are linked in some cases. In this narrative review, CFS/ME and cancer are introduced, along with their known and putative mechanistic connections to multiple stressors including ionizing radiation. Next, we summarize findings from the literature that suggest the involvement of HPA-axis dysfunction, the serotonergic system, cytokines and inflammation, metabolic insufficiency and mitochondrial dysfunction, and genetic changes in CRF and CFS/ME. We further suspect that the manifestation of fatigue in both diseases and its causes could indicate that CRF and CFS/ME lie on a continuum of potential biological effects which occur in response to stress. The response to this stress likely varies depending on predisposing factors such as genetic background. Finally, future research ideas are suggested with a focus on determining if common biomarkers exist in CFS/ME patients and those afflicted with CRF. Both CFS/ME and CRF are relatively heterogenous syndromes, however, it is our hope that this review assists in future research attempting to elucidate the commonalities between CRF and CFS/ME.
... 15 Reported sensitivity of cosyntropin stimulation test in patients with FM is even lower, potentially misdiagnosing up to 50% of cases. [16][17][18] The sensitivity of cosyntropin stimulation test in this study was also quite low at 21.4%. Therefore, CST may be a helpful test to diagnose SAI in patients with FM but cannot reliably rule out disease. ...
Full-text available
Purpose: Patients with fibromyalgia (FM) may demonstrate low cortisol concentrations during diagnostic evaluation. However, it remains unclear whether low cortisol reflects underlying pituitary dysfunction. We aimed to determine if a subset of patients with FM have concomitant secondary adrenal insufficiency (SAI) and growth hormone deficiency (GH). Patients and methods: This is a retrospective study of all patients with FM diagnosed with SAI based on abnormal insulin tolerance test (ITT) between June 2002 and August 2019. Patients were excluded if they had other reasons for SAI. Measurements include cortisol and GH during ITT in all patients, and peak cortisol during cosyntropin stimulation test in a subset of patients. Results: We identified 22 patients (median age of 38 years (range 19-65), 18 (82%) women) diagnosed with secondary AI based on abnormal ITT (peak median cortisol level of 11 mcg/dL (range 5.4-17)). Concomitant GH deficiency was diagnosed in 19 (86%) patients. Cosyntropin stimulation test was performed in 14 (64%) patients and was normal in 11 (79%) (peak cortisol ≥18 mcg/dL). MRI pituitary imaging was performed in 20 patients and showed no significant pituitary pathology. All patients were started on physiologic glucocorticoid replacement, and 5 patients were started on GH replacement. Of the 13 patients with follow-up, 8 (62%) reported symptom improvement after starting treatment. Conclusion: Patients with FM can have concurrent SAI and GH deficiency. Cosyntropin stimulation test should not be used to exclude SAI in patients with FM. Appropriate glucocorticoid and/or GH replacement may improve symptoms in some patients.
... A large body of evidence is dedicated to elucidating the relationship between pain and stress. Numbers of studies demonstrate dysregulation of the hypothalamic pituitary adrenal ( H P A ) a x i s i n C P a n d C W P , b o t h h y p e r -a n d hypocortisolemia [38,39,[41][42][43]]. An ACTH hyperresponsiveness and a relative adrenal hypo-responsiveness were shown in studies on HPA axis dysfunction in FMS patients, indicating a tertiary (hypothalamic or suprahypothalamic level) of hypoadrenalism [44]. ...
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Purpose of Review Recent studies have linked fibromyalgia (nociplastic pain) and depression to neuroinflammation. Restless legs syndrome (RLS) is highly prevalent in CWP (chronic widespread pain) and FMS (fibromyalgia syndrome) as well as in depression. This review focuses on evidence in the relationship between CWP and RLS and possible common pathophysiological mechanisms. Recent Findings CWP is chronic pain spread over various locations of the body and is a cardinal sign of fibromyalgia. Poor sleep quality is a common symptom in fibromyalgia as well as high levels of fatigue, poor cognition, and other associated features which include depression, headache, and abdominal pain. Evidence for a bilateral relationship between pain and sleep deficit is robust. The latest research focus is not only on insomnia symptoms in chronic pain but also on other types of sleep disorders such as RLS which is characterized by complaints of an “urge to move” frequently associated with dysesthesias. These sensations can also have painful characteristics. Thus, there is a possible overlap between these two entities. The high prevalence of RLS (33–54%) in CWP has been shown in several studies. The pathophysiological mechanisms behind CWP and RLS are still not completely known, but there is a rising amount of evidence on proinflammatory and neuroinflammatory processes in CWP. In RLS, there are links to dopaminergic dysfunction and more generally to monoaminergic dysfunctional circuits, BID (brain iron deficiency), altered glutamatergic neurotransmission, and genetic traits. Depression is a common comorbidity as well in CWP as RLS, and proinflammatory mechanisms have also been demonstrated in this condition. Summary The association between CWP and RLS is shown to be high and the pathogenesis of both conditions is still not completely understood. Recent research is focusing on proinflammatory and neuroinflammatory processes, not uniquely emerging in fibromyalgia/CWP, but inflammatory features have been found in depression as well as in sleep deficit. Proinflammatory/neuroinflammatory processes may be an underlying, common factor in both CWP and RLS that future research should investigate further.
... Uma significativa correlação tem sido observada, ainda, entre comportamento de dor e resposta de estresse. A fibromialgia, dor crônica musculoes-quelética difusa ao longo do eixo axial, tem tido sua etiologia atribuída a fatores estressores presentes ao longo do desenvolvimento do portador; nessa patologia não é incomum a exacerbação dos sintomas durante períodos de estresse físico ou emocional (Holtorf, 2007;Okifuji & Turk, 2002;Reis & Rabelo, 2010;Van Houndenhove, Egle, & Luyten, 2005). Estudos examinando enxaqueca, tipo específico de cefaleia, também identificaram uma relação significativa com situações estressoras. ...
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O presente estudo procurou avaliar os efeitos de um protocolo de intervenção comportamental para trabalhadores com dor crônica. Participaram cinco funcionárias públicas com idade entre 36 e 61 anos; três tinham o diagnóstico de fibromialgia, uma de enxaqueca e uma neurite. A intervenção foi programada utilizando um procedimento de linha de base múltipla em quatro fases: 1) linha de base; 2) módulo 1 (psicoeducação); 3) módulo 2 (relaxamento); 4) módulo 3 (estratégias de enfrentamento). Para avaliação foram utilizados: roteiro de entrevista; inventário de sintomas de stress para adultos de Lipp (ISSL); inventário Beck de depressão e de ansiedade; escala Fast e inventário WHOQOL-BREF. Registros individuais mostraram uma relação entre a intensidade da dor e pouca efetividade nas condições de trabalho (r=0,86; p
... Uma significativa correlação tem sido observada, ainda, entre comportamento de dor e resposta de estresse. A fibromialgia, dor crônica musculoes-quelética difusa ao longo do eixo axial, tem tido sua etiologia atribuída a fatores estressores presentes ao longo do desenvolvimento do portador; nessa patologia não é incomum a exacerbação dos sintomas durante períodos de estresse físico ou emocional (Holtorf, 2007;Okifuji & Turk, 2002;Reis & Rabelo, 2010;Van Houndenhove, Egle, & Luyten, 2005). Estudos examinando enxaqueca, tipo específico de cefaleia, também identificaram uma relação significativa com situações estressoras. ...
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The present study aimed to assess the effects of a brief behavioral intervention protocol designed for public employees with a diagnosis of chronic pain. Five female public employees participated, aged between 36 and 61 years; three who had been diagnosed with Fibromyalgia, one with Migraine, and one with Neuritis. The intervention was programmed based on a multiple baseline procedure in four phases: 1) Baseline; 2) Module 1 (Psychoeducation); 3) Module 2 (Relaxation); and 4) Module 3 (Coping Strategies). The following assessment instruments were used: Interview Script; Inventory of Stress Symptoms for Adults Lipp (ISSL); Beck Depression and Anxiety Inventories; FAST Scale and WHOQOL-BREF Inventory. Individual records showed a correlation between pain intensity and poor effectiveness at work (r = 0.86, p <0.000). Three participants showed an increase in their total score of quality of life (WHOQOL-BREF). Moreover, results revealed a decrease in depression, anxiety and stress.
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Objective: Internal physiological processes govern multiple state variables within the human body. Estimating these from point process-type bioelectric and biochemical observations is a challenge. Here we seek to estimate cortisol-related energy production and sympathetic arousal based on point process and continuous-valued data while permitting an external influence to affect the state estimates. Methods: Traditional point process state-space methods, such as those used for estimating the aforementioned quantities from cortisol and skin conductance measurements respectively, suffer from the inability to permit the state estimates to also fit to an external influence (e.g. labels) or be guided by it. Here we modify an existing recurrent neural network (RNN) approach for state-space estimation through a weighted cost-function to enable a hybrid estimator that has this capability. Results: Results on cortisol data based on a hypothetical sleep-wake influence term show how energy production can be estimated by permitting the estimates to fit to the external influence as much as desired. We further show how overfitting may be reduced by using circadian rhythm-based influence terms. Results on skin conductance data also indicate how the method can be used to estimate sympathetic arousal in an experiment containing stressors and relaxation, and permit an external influence as well. Conclusion: The RNN-based hybrid method is thus able to recover internal physiological states from point process and continuous-valued observations while permitting an external influence to guide the estimates. Significance: The hybrid estimator could be embedded within wearable monitors that can be tailored based on domain expertise or individual feedback.
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We here provide an overview of treatment trials for prolonged intensive care unit (ICU) patients and theorize about their relevance for potential treatment of myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). Specifically, these treatment trials generally target: (a) the correction of suppressed endocrine axes, notably through a “reactivation” of the pituitary gland's pulsatile secretion of tropic hormones, or (b) the interruption of the “vicious circle” between inflammation, oxidative and nitrosative stress (O&NS), and low thyroid hormone function. There are significant parallels in the treatment trials for prolonged critical illness and ME/CFS; this is consistent with the hypothesis of an overlap in the mechanisms that prevent recovery in both conditions. Early successes in the simultaneous reactivation of pulsatile pituitary secretions in ICU patients—and the resulting positive metabolic effects—could indicate an avenue for treating ME/CFS. The therapeutic effects of thyroid hormones—including in mitigating O&NS and inflammation and in stimulating the adreno-cortical axis—also merit further studies. Collaborative research projects should further investigate the lessons from treatment trials for prolonged critical illness for solving ME/CFS.
The role of the low dose (1 microgram) ACTH stimulation test in the evaluation of patients with pituitary diseases was systematically assessed by relating its results to those obtained on gold standard tests of hypothalamo-pituitary-adrenal (HPA) reserve, such as insulin-induced hypoglycemia or a metyrapone challenge. Ten patients with pituitary diseases (8 men and 2 women) and proven impairment of HPA function and 9 patients (5 men and 4 women) with similar pituitary pathologies but preserved HPA function were studied (pituitary controls). A group of 7 normal volunteers (3 men and 4 women) served as normal controls. None of the subjects was taking glucocorticoids on a chronic basis or had been taking any recently. All subjects underwent ACTH tests at 0800 h with 3 different levels of stimulation (1, 5, and 250 micrograms), and serum cortisol was assayed 0, 30, and 60 min after injection. A pass result was defined as a peak cortisol value of 497 nmol/L or more. Basal cortisol values were indistinguishable...
In the past few years, a syndrome of extreme persistent fatigue and associated symptoms, often including myalgia and/or disturbances of cognitive function, has been increasingly studied in a number of countries. In 1988, Holmes et al. established a working definition (Table 1) for this syndrome, referred to as chronic fatigue syndrome (CFS), in order to provide a starting point for various investigators to compare their results more meaningfully. CFS is apparently a heterogeneous collection of illnesses, emphasized by the number of names attributed to this constellation of symptoms in the literature (Krueger, see below). Since Epstein-Barr virus (EBV) has been implicated as one cause of post-infectious chronic fatigue syndrome (PICFS) (Tobi et al., 1982; Jones et al., 1985; Straus et al., 1985) and chronic EBV (CEBV) infection has become a widely diagnosed illness, a re-evaluation of CFS appears appropriate for the Third International Symposium on Epstein-Barr Virus and Associated Diseases.
Conference Paper
HPA axis abnormalities in FM, CFS, and other stress-related disorders must be placed in a broad clinical context. We know that interventions providing symptomatic improvement in patients with FM and CFS can directly or indirectly affect the HPA axis. These interventions include exercise, tricyclic anti-depresssants, and serotonin reuptake inhibitors. There is little direct information as to how the specific HPA axis perturbations seen in FM can be related to the major symptomatic manifestations of pain, fatigue, sleep disturbance, and psychological distress. Since many of these somatic and psychological symptoms are present in other syndromes that exhibit HPA axis disturbances, it seems reasonable to suggest that there may be some relationship between basal and dynamic function of the HPA axis and clinical manifestations of FM and CFS.
Main Results: Patients had a higher mean (+/- SD) CD4/CD8 T-cell ratio than matched healthy controls (3.16 +/- 1.5 compared with 2.3 +/- 1.0, respectively; P < 0.003). Magnetic resonance scans of the brain showed punctate, subcortical areas of high signal intensity consistent with edema or demyelination in 78% of patients (95% Cl, 72% to 86%) and in 21% of controls (Cl, 11% to 36%) (P < 10 -9 ). Primary cell culture of lymphocytes showed active replication of HHV-6 in 79 of 113 patients (70%; CI, 61% to 78%) and in 8 of 40 controls (20%; Cl, 9% to 36%) (P < 10 -8 ), a finding confirmed by assays using monoclonal antibodies specific for HHV-6 proteins and by polymerase chain reaction assays specific for HHV-6 DNA. • Conclusions: Neurologic symptoms, MRI findings, and lymphocyte phenotyping studies suggest that the patients may have been experiencing a chronic, immunologically mediated inflammatory process of the central nervous system. The active replication of HHV-6 most likely represents reactivation of latent infection, perhaps due to immunologic dysfunction. Our study did not directly address whether HHV-6, a lymphotropic and gliotropic virus, plays a role in producing the symptoms or the immunologic and neurologic dysfunction seen in this illness. Whether the findings in our patients, who came from a relatively small geographic area, will be generalizable to other patients with a similar syndrome remains to be seen. Annals of Internal Medicine. 1992: 116:103-113