Evaluation ofimvestigations to diagnose the cause ofdizziness in
elderly people: a community based controlled study
Nicki R Colledge, Robin M Barr-Hamilton, SusanJ Lewis, Robin J Sellar, Janet A Wilson
Objective-To compare the findings in dizzy
elderly people with those in controls of a similar
age to identify which investigations differentiate
dizzy from non-dizzy patients and to design an in-
Design-Communitybased study ofclinical and
laboratory findings in dizzy and control elderly
Setting-Research outpatient clinic at a teach-
Subjects-149 dizzy and 97 control subjects aged
over 65 years recruited from a community survey
and articles in the local press.
Main outcome measures-Findings on physical
exanmation, blood testing, electrocardiography
(at rest and over 24 hours), electronystagmo-
graphy, posturography, and magnetic resonance
imaging of head and neck (125 (84%) dizzy
subjects and 86 (89%/6) controls); hospital anxiety
and depression score; responses to hyperventila-
tion, carotid sinus massage, and the Hallpike ma-
electronystagmography, and magnetic resonance
imaging failed to distinguish dizzy from control
subjects because of the frequency of asympto-
matic abnormalities in controls. Posturography
and clinical assessment (physical examination,
dizziness provocation, and psychological assess-
ment) showed significant differences between the
groups. A cause of the dizziness was identified
from clinical diagnostic criteria based on ac-
cepted definitions in 143 subjects, with 126 having
diagnoses were central vascular disease (105) and
cervical spondylosis (98), oft-en accompanied by
poor vision and anxiety.
Conclhsion-Expensive inestigations are rarely
helpful in dizzy elderly people. The cause of the
dizziness can be diagnosed in most cases on the
basis of a thorough clinical examination without
recourse to hospital referl.
Dizziness is reported by about 30% of people aged
over 65 years," and in the United States it is the most
common presenting complaint in office practice among
patients aged over 75 years.3 Dizziness is a difficult
diagnostic problem in elderly people as it has many
potential causes and patients often find it difficult to
articulate the nature oftheir symptoms.
Most previous studies on dizziness in older people
have been retrospective, uncontrolled, and based in sec-
common diagnosis reported in referred patients
included are unlikely to be representative of those who
attend their general practitioner with dizziness.
settings."' The most
vestibular disease,79-12 but the patients
We compared the findings in dizzy elderly people
recruited from the community with those in elderly
control subjects to identify the investigations that
construct an investigational algorithm.
Subjects over 65 years old were invited to take part
through articles in the local press and through our local
survey ofdizziness in 1000 people over 65.' Those who
called a contact telephone number were sent infor-
mation about the study. We obtained signed consent
and the permission ofeach person's general practitioner
before formal recruitment. Only those who suffered
from dizziness every three months or more were
recruited to the dizzy group, and only those who had
never been dizzy were recruited to the control group.
No other inclusion or exclusion criteria were applied.
The study had full approval ofan ethics committee. We
intended to study 100 dizzy and 100 control subjects,
but all 149 suitable dizzy volunteers were recruited to
avoid selection bias.
current treatments, and functional ability. One of us
(NRC) performed all the clinical assessments.
Visual acuity and assessment of the cardiovascular,
neurological, and locomotor systems were included in a
physical examination. All subjects were assessed for diz-
ziness during 2 minutes of hyperventilation, during
rapid head or neck movement, after standing up from
supine (blood pressure was measured at once and after
one minute), and during Romberg's test. Carotid sinus
massage was performed under continuous electrocar-
diographic monitoring, except in subjects with a carotid
bruit or those who were taking digoxin. The Hailpike
manoeuvre was performed for benign paroxysmal posi-
tional vertigo. Each subject was tipped from sitting to
supine with their neck extended over the end ofa couch,
first with their head rotated to the right and then
repeated with the head to the left. Subjects with benign
paroxysmal positional vertigo have a latent period of a
few seconds before they develop acute vertigo and
torsional nystagmus, which last up to 1 minute and
fatigue on repeat testing." Patients were also adminis-
tered the hospital anxiety and depression scale, a ques-
tionnaire of 20 items validated for use in outpatient
settings,'4 and the abbreviated mental test."1
A blood sample was taken for measurement ofblood
count, erythrocyte sedimentation rate, urea and electro-
lyte concentrations, random glucose concentration,
triglyceride concentration, and cholesterol concentra-
tion and for performance of liver and thyroid function
tests. Patients also had 12 lead and 24 hour ambulatory
Posturography was performed
computerised force platform.'6 The contribution of
dizzy symptoms, medical
VOLUME 313 28 SEPTEMBER 1996
Edinburgh EH3 9YW
Nicki R Colledge, senior
lecturer in geratrc medicine
Susan J Lewis, researchfelow
in geriatrc mediane
Royal Infirimry of
Edinburgh NHS Trust,
Edinburgh EH3 9YW
principal audiological scientist
Edinburgh EH4 2XU
Robin J Sellar, consudtant
Otolaryngology, Head and
Neck Surgery, University
ofNewcastle upon Tyne,
Newcastle upon Tyne
Janet A Wilson, professor
DrN R Colledge, Geriatric
Medicine Unit, Liberton
Table 1-Characteristics of dizzy and control subjects.
(percentages) of subjects
Values are numbers
(n = 149)
Ischaemic heart disease
Regular alcohol intake
Walking aid used
Table 2-Findings on physical examination in dizzy and control subjects. Values are
numbers (percentages) of subjects
(n = 149)
(n = 97)
Reduced power in legs
Increased tone in legs
Abnormal results in heel-knee test
Increased reflexes in legs
Extensor plantar responses
Limited neck movement
Limited hip movement
Less than 6/9 in both eyes
Table 3-Numbers (percentages) of dizzy and control subjects with positive
responses to provocation of dizziness
Carotid sinus massage
Fall in blood pressure:
No fall in blood pressure:
Table 4-Results of psychological testing in dizzy and control subjects. Values are
numbers (percentages) of subjects
Normal (score <8)
Borderline (score 8-10)
Abnormal (score a11)
Normal (score <8)
Bordedline (soore 8-10)
Abnormal (score ->11)
Abbreviated mental test:
each sensory system was assessed by recording the sway
path length of a subject's centre of gravity while stand-
ing for 1 minute on a firm surface with eyes open (test
1), on a firm surface with eyes closed to remove visual
input (test 2), on a foam surface with eyes open to
remove reliable proprioceptive input (test 3), and on a
foam surface with eyes closed, which effectively leaves
only vestibular input (test 4).
Vestibular testing was performed using computed
electronystagmography with a Nicolet Nystar system
(Nicolet Instruments, Warwick). Saccadic eye move-
ments, pursuit ofan object, optokinetic nystagmus, and
recorded; bithermal caloric testing was also performed.
Magnetic resonance images of head and neck were
obtained with a Siemens 1.5 Tesla scanner; images were
reported according to a standardised format by a
consultant neuroradiologist (RJS) who was blind to
whether the subject had dizziness. Subjects with cardiac
pacemakers or intracranial ferromagnetic clips did not
Analysis was performed using the statistical package
for the social sciences (spss). The Mann-Whimey U
test, Student's t test, and x2 tests were used with Yates's
correction for continuity and Fisher's exact test as
posturography was skewed, so the data were trans-
formed logarithmically before analysis. Subjects were
categorised as having normal or abnormal sway using
reference intervals previously derived from normal vol-
unteers aged 60-70 and over 70.16
We recruited 149 subjects with dizziness and 97 con-
trols. The mean age of the dizzy subjects was 76.3 (SD
6.2) years, and 69 (49%) were men; the mean age ofthe
controls was 76.0 (5.8) years, and 39 (40%) were men.
Significantly more dizzy subjects were smokers and had
a history ofmyocardial infarction or angina, stroke, ear
disease, and eye disease (table 1). Dizzy subjects took a
median of three
Most dizzy subjects (1 16) defined their symptoms as
unsteadiness, 37 as vertigo, and 89 as light-headedness,
with 83 describing more than one sensation. Most
symptoms were longstanding (more than six months in
140 patients) and episodic (in 130 patients). Symptoms
were provoked by standing up in 94 patients, bending in
86, head or neck movement in 86, turning in bed in 20,
and anxiety in 43; dizziness occurred spontaneously in
70 patients. Forty three dizzy subjects had fallen, but
other associated symptoms were uncommon. Syncope
occurred in nine subjects.
Physical examination of the dizzy and control sub-
jects showed significant differences in the neuromotor
and locomotor systems (table 2) but not in sensory or
cranial nerve function or in the frequency of femoral
bruits or cardiac murmurs. Most provocation tests pro-
duced significantly more positive responses in the dizzy
group (table 3). On changing posture significantly more
dizzy subjects had symptoms than a drop in blood
Psychological testing showed significant differences
between the two groups (table 4). Although more dizzy
subjects scored less than 10 in the abbreviated mental
test, no subject scored less than 7.
whilecontrols took one
RESULTS OF INVESTIGATIONS
No significant differences were found between the
two groups in the results of blood tests or in the
voLuME 313 28 SEPTEMBER 1996
Table 5-Results of posturography in dizzy and control
subjects. Values are numbers (percentages) of subjects
(n = 149)
(n = 97)
1: Standing on firm base,
2: Standing on firm base,
3: Standing on foam
base, eyes open
4: Standing on foam
base, eyes closed
Table 6-Diagnosis of cause of dizziness in 149 dizy
No of subjects
Central vascular disease
Anxiety or hyperventilation
Benign positional vertigo
More than one diagnosis
Neck disease and central vascular disease:
Poor vision only
Anxiety or hyperventilation only
Twenty four hour ambulatory electrocardiography gave
normal results in 104 (70%) dizzy subjects, of whom
half had symptoms during the recording, and in 71
(73%) control subjects. The most common abnormality
in the remainder of both groups was brief episodes of
paroxysmal atrial fibrillation. No subject in either group
had associated symptoms.
Most subjects in both groups (119 (80%) v 77
(79%)) had two
or more electronystagmographic
abnormalities. There was no difference in rate or type of
abnormality between the two groups, as assessed by the
contrast, posturography showed
significant differences in rates ofabnormality in all tests
Overall, 125 (84%) dizzy subjects and 86 (89%) con-
trol subjects underwent magnetic resonance imaging. In
the remainder, scanning was contraindicated, refused,
or not tolerated. Abnormalities were-widespread and
present in most subjects regardless of group. Eighty
seven (70%) dizzy subjects and 57 (66%) control
subjects had facet joint degeneration, 105 (84%) dizzy
subjects and 70 (81%) controls had cerebral atrophy,
and 85 (68%) and 64 (74%) respectively had white
matter lesions in the cerebral hemispheres.
accepted definitions to diagnose the cause of dizziness
(box 1) in the affected subjects (table 6). There were no
significant differences in the prevalence of posturo-
clinically based criteriaderived from
To our knowledge, this is the first study to apply a
community based sample of elderly subjects. Some
selection bias is inevitable: very frail elderly people may
have felt unable to take part; those more concerned
about their symptoms may have been more likely to vol-
unteer (which might explain the frequency of anxiety
found in the dizzy group); and those with more sinister
causes may have been identified earlier by their general
practitioners. None the
subjects is likely to represent those people who are most
difficult to manage in general practice. The control
group may have been fitter than average for their age,
but they were no different from the dizzy subjects in
terms of age and functional ability.
less, our sample of dizzy
USE OF FORMAL INVESTIGATIONS
Routine use of electrocardiography, electronystag-
testing, and magnetic resonance
imaging is unhelpful because ofthe frequency ofabnor-
malities in symptom free subjects. The high prevalence
ofasymptomatic abnormalities in healthy volunteers on
electronystagmography is remarkable and doubtless
partly explains why previous uncontrolled studies have
claimed such a high rate ofvestibular disease in this age
group.7 9-12 Our study has confirmed the frequency with
which magnetic resonance imaging abnormalities occur
in symptom free elderly subjects.20 21
Posturography gave abnormal results more often in
dizzy subjects than controls, but it lacked diagnostic
specificity, perhaps because most subjects had several
diagnoses. Its value may therefore be more as a measure
of severity of disability or response to treatment.
Most subjects had several causes of dizziness that
could be elicited from clinical assessment without
further formal investigation. All subjects were examined
by the same person so assessments are likely to have
been consistent, but the fact that she could not be
blinded to whether subjects had dizziness is a weakness
of the study.
The presence of an abnormal gait (marche a petits
pas) with varying combinations of increased reflexes
and tone in the legs, abnormal coordination and exten-
sor plantar responses, and comparative sparing of the
upper half of the body is in keeping with a diagnosis of
cerebrovascular disease or "pseudoparkinsonism."22 Its
association with postural instability and falls is well rec-
ognised. The lack of any clinically significant sensory
loss or cranial nerve abnormality was surprising, as pre-
vious reports have suggested that these are significant
causes ofimbalance in old age.23
Cerebrovascular and neck disease were far more
common than peripheral vestibular disease in our com-
munity derived sample. The finding that dizzy subjects
more commonly had a history of ischaemic heart
disease, stroke, and smoking and had a carotid bruit on
examination suggests that vascular disease may be the
most important pathophysiology underlying dizziness in
elderly people. It may also explain why more dizzy sub-
jects took aspirin, diuretics, and calcium antagonists,
although the drugs themselves could also contribute to
Visual impairment and anxiety commonly accompa-
nied dizziness, but they were rarely the only causes. By
contrast, anxiety is often the cause of dizziness in
younger people.7 24 None the less, efforts to improve
symptoms in elderly people.
Others have noted a high prevalence of the carotid
sinus syndrome among
elderly people who
unexplained dizziness, falls, and syncope, particularly
when carotid sinus massage is performed with the
patient upright."7 We found no such evidence, but our
subjects were less highly selected and did not have tilt
testing, so some ofour subjects might also have had this
condition, although most had at least two other causes
VOLUME 313 28 SEPTEMBER 1996
Chronic dizziness in anelderly patient
Character - Vertigo, light headedness, or unsteadiness
Provocative factors - For example, postural change, head or neck movement,anxiety, none (occurs spontaneously)
Associated symptoms - Blackouts, falls, tinnitus, or hearing loss
Test visual acuity
Take smoking history
Refer for 24 hour
and carotid sinus massage
Are there blackouts
Are there symptoms/abnormalities during-
* Vigorous head and neck movement?|
* Cervical spondylosis
* Measurement of blood pressure while erect and supine?
Heel to toewalking ( abnormal examine neuromotorsysteminlegs)
* Two minutes ofvoluntary overbreathing?|
* Hallpikemanoeuvre(seetext fordetails)?
Benign positional vertigo
Do findings fitdiagnostic criteria?
Algorithm for evaluation of cause of dizziness in elderly patients in general practice
The frequency of symptoms on postural change and
the lack of correlation with any drop in blood pressure
has been previously noted.25 This may be due to an
impairment in cerebral blood flow that can occur with-
out a drop in systemic blood pressure on postural
change.26 Interestingly, postural symptoms are more
Diagnostic criteria for causes ofdizziness
Benign paroxysmal vertigo
Brief episodes of vertigo on change of position
Symptoms on head or neck movement with
reduced range ofneck movement7
Fall of 20 mm Hg in systolic pressure or of 10
mm Hg in diastolic blood pressure one minute
after standing from the supine position with
Unsteadiness with or without light-headedness
in association with an abnormal gait (marche a
petits pas) and increased reflexes and tone, with
or without loss ofpower18
Anxiety score of more than 8 on hospital anxi-
ety and depression scale with or withiout repro-
duction ofsymptoms on hyperventilation719
Visual acuity reduced to less than 6/9 in both
Central vascular disease
Anxiety or hyperventilation
No diagnosis possible
* Dizziness can be diagnosed in most elderly peo-
ple on the basis offindings in the neurological and
locomotor systems, supplemented by simple dizzi-
ness provocation testing
* Expensive investigations are rarely helpful in the
diagnosis of dizziness in elderly people
* The most common causes of dizziness in older
people are central vascular disease and cervical
* Poor vision and anxiety often accompany but are
rarely the sole cause of dizziness
* These findings point to a definitive role for the
general practitioner in the assessment ofdizzy eld-
impaired functional status than postural hypotension."
associated with a history of falling and
ADVICE TO GENERAL PRACTMONERS
As a result of this study, general practitioners should
feel confident that a clinical assessment, including the
provocation of dizziness, will identify the causes of diz-
ziness in most of their elderly patients (fig 1). Evidence
of poor vision, anxiety, and smoking should be sought
and actively managed. Much of such an assessment
could be performed by a practice nurse.
We think that patients with blackouts and those
whose symptoms and signs do not fit clearly defined
diagnostic criteria should be referred. Given the low
frequency with which vestibular disease occurred,
otolaryngological assessment will rarely be fruitful.
Geriatricians, with their experience of multisystem dis-
ease, may be more appropriate specialists to perform
The results of this study should herald a shift away
from protracted investigation programmes for dizzy eld-
erly subjects. Now that we have clearly defined diagnos-
tic criteria that identify the causes of dizziness in most
elderly people, future research should be directed at
improving management. As many of the causative con-
ditions can only be controlled symptomatically rather
than cured, rehabilitation seems the best option. Elderly
people's balance can be improved by training,7 28 and
new techniques such as posturography with visual feed-
back and vestibular rehabilitation should be examined.
Given the frequency with which dizzy people fall, such
research is a matter ofurgency.
We thank the volunteers for their help and patience, and Dr
Scott Murray, department of general practice, University of
Edinburgh, and Dr Isobel Wilson, Morningside Medical Prac-
tice, Edinburgh, for their useful comments.
Funding: Research into Ageing (ref 9/110); Chief Scientist's
Office, Scottish Home and Health Department (refK/MRS/50/
Conflict ofinterest: None.
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3 Sloane P, Blazer D, George LK. Dizziness insa community elderly popula-
tionJgAm GerarSO7c 1989;37:101-8.
4 Grimley Evans J. Transient neurological dysfunction andriskcofstroke in an
elderly English population: the different significance of vertigo and
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6 Ormna EJ, Koskcenoja M. Postural
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8 Belal A, Glorig A. Dysequilibrium ofageing (presbyastasis). J Laryngol Owl Download full-text
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13 Dix MR, Hailpike CS. The pathology, symptomatology and diagnosis of
certain common disorders of the vestibular system. Annals of Otology
14 Aylard PR, Gooding JH, McKenna PJ, Snaith RP. A validation study of
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15 Hodkinson HM. Evaluation ofa mental test score for assessment ofmental
impairment in the elderly. Age Ageing 1972;1:233-8.
16 Colledge NR, Cantley P, Peaston I, Brash H, Lewis S, Wilson JA. Ageing
and balance: the measurement of spontaneous sway by posturography.
17 McIntosh S, Da Costa D, Kenny RA. Outcome of an integrated approach
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referred to a "syncope" clinic. Age Ageing 1993;22:53-8.
18 Hopkins A.
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(Accepted 7August 1996)
Doctors' retainer scheme in Scotland: time for change?
Alison Douglas, Ian McCann
Medical School, Aberdeen
Alison Douglas, women
Ian McCann, research
Objectives-To describe the present doctors'
retainer scheme in Scotland and ascertain the
need for change.
Design-Semistructured postal questionnaires
to current and past members of the doctors'
retainer scheme and general practitioner employ-
Setting-Scotland, October to December 1994.
Subjects-1521160 current and 1041124 former
members responded together with 1011118 general
Results-93% ofmembers currently working in
general practice were either vocationally trained
or had previously worked as principals. 84% of
current members held postgraduate qualifica-
tions. 73% offormer members had left the scheme
within 4 years and 72% of current members had
been with the scheme for 4 years or less. 66% of
current members said that the scheme prevented
them from leaving medicine. Both members and
employers were dissatisfied with the current limit
oftwo working sessions per week, 77% ofemploy-
ers wanting it increased. 61% ofcurrent members
would not have joined the scheme if suitable part
time work had been available and 46% of those
would have preferred to work flexibly, up to 5 ses-
sions per week. 52% of members do not receive
BMA rates of pay and, of those, 46% work more
than 3.5 hours per session.
Conclusion-The scheme appears to be appre-
ciated and would be more so if inconsistencies in
pay and conditions were addressed. An increase in
the permitted number of weekly sessions would
enable these highly qualified doctors to maintain
their skills and confidence.
Half ofmedical graduates are now women and there
is an increasing demand for part time training and work
from both men and women.' 2 Opportunities are still
limited, however, and this study aimed to explore the
existing and potential usefulness ofthe doctors' retainer
scheme, which has been in existence in Scotland since
1972 (and also in the rest ofthe UK).
The scheme was established to "encourage doctors
who were temporarily unable to practise because of
domestic commitments to remain in touch with medical
activity and continue their training in order eventually
to return to substantial practice." The conditions of
membership have remained unchanged3
Work up to a maximum of 2 paid sessions per week.
Receive in addition to salary an annual retainer fee
(currently £290) paid by the health board.
Keep up registration with General Medical Council and
belong to a defence organisation.
Subscribe to a professional journal.
Attend at least 7 educational sessions a year.
Work at least 12 paid service sessions per year.
In general practice one session a week is reimbursed to
practices by health boards. The present
reimbursement is £40.50 per session.
Recently, the scheme has been felt to be in need of
modernisation,5 6 and in 1992 the Advisory Committee
on Medical Establishment recommended that doctors
in the scheme should be allowed to work up to four ses-
sions per week and do controlled short term locum
work; that the retainer fee should be updated annually
to cover expenses; and that time spent in the scheme
should be limited to five years.7 There is no indication
that these recommendations will be implemented, and
there has been no large study to help shape policy. We
therefore carried out a structured inquiry of both
present and past members of the scheme in Scotland
Our aims were to: (a) describe the characteristics of
the current membership, to assess training needs; (b)
acquire data on length of membership and subsequent
career development of former members; (c) gather
information on pay and conditions and other factors
affecting satisfaction with the scheme; and (d) seek sug-
gestions for improving the scheme.
Names and addresses ofcurrent members were easily
obtained from the five Scottish postgraduate centres. It
was harder to identify former members because the
length of time that records are kept varies between the
five centres, and our data are therefore incomplete.
Current addresses offormer members were found using
information from staff in postgraduate centres.
Semistructured postal questionnaires were sent to
current members and those former members who could
28 SEPTEMBER 1996