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n clinical n
© Managed Care &
Healthcare Communications, LLC
patients requiring 2 or more LL drugs to achieve optimal blood pressure
and cholesterol levels.3,8,13 Adequate adherence to medication regimens
is essential to decrease the risk for hospitalization and healthcare ex-
penditures.14 Poor adherence to an-
tihypertensive and LL regimens can
accelerate the development of CVD,
which can lead to a decreased qual-
ity of life and premature death.3 The
medication burden of patients with
deaths.1,2 Annual direct and indirect costs of CVD in 2007 were esti-
mated to be approximately $431.8 billion.1,2 Several factors increase
the risk of CVD such as hypertension, age (>55 years for men and
>65 years for women), dyslipidemia, diabetes mellitus or glucose in-
tolerance, renal dysfunction, family history of premature CVD (rela-
tive’s age <55 years in men and <65 years in women), obesity, physical
inactivity, and smoking.3 Studies have shown that CVD risk factors
coexist. Patients with hypertension often have 1 or more concomitant
risk factors, including diabetes mellitus or glucose intolerance, obe-
sity, and dyslipidemia, all components of the metabolic syndrome.4,5
Less than 20% of patients with hypertension have no other CVD risk
factors.4 Two of the most prevalent and asymptomatic risk factors for
CVD, hypertension and dyslipidemia, commonly coexist, and the risk
of CVD associated with having both is greater than the risk associ-
ated with having hypertension or dyslipidemia alone.4,6 The US Third
National Health and Nutrition Examination Survey provides an esti-
mated prevalence of concomitant hypertension and dyslipidemia of
about 15% among adults, which equates to approximately 30 million
adults in the United States.7
The National Cholesterol Education Program Adult Treatment
Panel III guideline recommends aggressive management of patients with
concomitant hypertension and dyslipidemia.8 Meta-analyses and clinical
trials have found that antihypertensive and lipid-lowering (LL) medica-
tions significantly reduce the risk of CVD and all-cause mortality among
patients with CVD risk factors.9-12
Medication therapy for the treatment of hypertension and dyslipi-
demia is becoming more challenging, as more than two-thirds of patients
require 2 or more antihypertensive drugs and an LL drug, with high-risk
ardiovascular disease (CVD) continues to be the leading
cause of morbidity and mortality in the United States.1,2 In
2002, CVD in the United States accounted for 1.4 million
In this issue
Take-away Points / p716
Full text and PDF
Effect of Medication burden on Persistent Use of
Lipid-Lowering Drugs Among Patients With Hypertension
Teisha A. Robertson, PharmD, MBA; Catherine E. Cooke, PharmD, BCPS; Jingshu Wang, PhD;
Fadia T. Shaya, PhD, MPH; and Helen Y. Lee, PharmD, MBA
Objective: To determine the effect of medica-
tion burden on persistent use of newly added
lipid-lowering (LL) drugs among patients with
Study Design: This retrospective database study
used medical and pharmacy claims from a mid-
Atlantic managed care organization. The cohort
was obtained from continuous member enroll-
ment in pharmacy and medical benefits from
January 1, 2003, to December 31, 2005.
Methods: Prescription claims were obtained for
18 months following the date of the first filled
LL prescription (ie, index date). Patients were
stratified into patients who changed LL drug
or strength (group 1) and patients who did not
change LL drug or strength (group 2). The primary
outcome measure was persistence to newly
added LL therapy. Persistence was defined by the
length of time a member remained on therapy
following the index date. The secondary outcome
measure was the medication possession ratio
(MPR). The MPR was calculated as the ratio of the
sum of the days’ supply of prescription filled di-
vided by the number of days filled, plus the days’
supply for the final prescription fill. Associations
between the daily medication burden, defined
as the number of unique drug products, and the
outcome measures were analyzed.
Results: In the cohort of 3058 patients, the
mean medication burden was 2.9 medications.
Medication burden was positively associated with
persistence and MPR through 18 months. Patients
who had greater medication burden had longer
persistence (P <.001). Likewise, patients who had
greater medication burden had higher MPRs and
were more likely to be considered adherent (MPR,
>80%) (P < .001 for both).
Conclusions: Patients with higher medication
burden had greater adherence to newly added LL
therapy. Medication burden should not deter clini-
cians from adding LL therapy. Among patients
with added LL therapy, more attention should
focus on patients who have changes to their LL
regimen compared with patients who continue on
the same LL prescription.
(Am J Manag Care. 2008;14(11):710-716)
For author information and disclosures,
see end of text.
VOL. 14, NO. 11
n THE AMErICAN JOUrNAL OF MANAGED CArE n?
Burden of lipid-lowering Drugs among Patients With Hypertension
CVD risk factors can be high and may affect medication ad-
herence; however, conflicting assessments have been reported.
Some investigators have reported an increase in adherence
among patients with higher medication burden, while others
have reported the opposite result.15-20 Given the need to man-
age patients at high risk for CVD with multiple medications,
it is important to elucidate the true effect of the number of
medications on adherence.
A retrospective study of medical and pharmacy claims was
performed to evaluate this. The objective was to assess the
effect of medication burden on persistence of newly added LL
drugs among patients with hypertension.
Data Sources and Patients
This retrospective database analysis used medical and
pharmacy claims from a mid-Atlantic managed care organi-
zation serving more than 1.2 million members with medical
and pharmacy benefits. The cohort included members with
continuous enrollment of pharmacy and medical benefits
from January 1, 2003, to December 31, 2005. Members were
included in the analysis if they had at least 1 International
Classification of Diseases, Ninth Revision, Clinical Modification
(ICD-9-CM) code for hypertension (401.xx) from January
1, 2003, to June 30, 2004, and at least 1 prescription for an
LL drug dispensed between July 1, 2003, and June 30, 2004.
Members were excluded from analysis if they had any of the
following: prescriptions for LL therapy before the first ICD-9-
CM code for hypertension in the study period; LL prescrip-
tions dispensed from January 1, 2003, to June 30, 2003; age
younger than 18 years on the index date (ie, the date of the
first filled LL prescription); more than 1 prescription for an LL
drug filled on the index date; an LL prescription with negative
days’ supply (a void in the prescription and the patient did
not receive the drug); only 1 filled LL prescription during the
study period; or ICD-9-CM diagnosis codes from January 1,
2003, to December 31, 2005, for comorbid diseases, including
HIV, cancer, dementia, Alzheimer’s disease, mental retarda-
tion or Down syndrome, schizophrenia, bipolar disorder, or
depression, that could affect adherence (Figure).
The first filled LL drug during the study interval was consid-
ered the index prescription. Patients included in the study had
the same observation period of 18 months following the index
date. Prescription claims were obtained for patients included
in the cohort for 18 months following the index date. To assess
for differences among patients who change or switch from 1
drug to another or change the dosage of their medication ver-
sus patients who remained on the same medication and dosage,
patients were stratified into 2 groups. Group 1 included pa-
tients who changed LL drug (including patients who switched
to a different strength of the same drug or to a different class of
the drug, as well as patients who added an LL drug). Group 2
included patients who did not change LL drug or strength (ie,
had the same prescription throughout the study).
Lipid-lowering drugs included all those on the US mar-
ket during the study period, including bile acid sequestrants,
statins, fibric acid derivatives (fibrates), cholesterol absorption
blockers, combination therapy of 2 medications in 1 formula-
tion, and others (eg, niacin). Data from medical and pharmacy
claims included unique deidentified patient number, patient’s
age on the index date, sex, disease diagnoses as defined by ICD-
9-CM codes, prescription information for all filled LL drugs
(drug name, prescription fill date, days’ supply, and copay-
ment), and a list of concurrently filled prescription medicines
6 months before and within 6 months after the index date.
Medication adherence was evaluated based on persistence
and the medication possession ratio (MPr). The primary out-
come measure, persistent use of an LL drug, was specified as
the length of time in days that patients remained on an LL
drug following the index date. A patient was deemed persis-
tent if he or she filled a prescription within a grace period
of 30 days from the end of the days’ supply of the prior pre-
scription.21-23 For patients who had changes to their index LL
regimen (group 1), persistent use of the index LL prescrip-
tion and persistent use of the switched LL prescriptions were
combined. Persistence was truncated to 548 days (18 months)
for patients with LL prescriptions that extended beyond the
18-month study period. The secondary outcome measure,
MPr, was calculated as the ratio of the sum of the days’ sup-
ply of prescription filled by the patient divided by the number
of days from the fill date of the index prescription to the last
fill date, plus the days’ supply for the final prescription fill.24
For patients who had changes to their index LL regimen, the
sum of the days’ supply of the index LL drug was added to the
sum of the days’ supply of the changed LL drugs, divided by
the number of days from the fill date of the index prescription
to the last fill date of the changed LL drugs, plus the days’
supply for the final prescription fill. The MPr was truncated
to a ratio of 1 for patients with a sum of days’ supply of filled
LL prescriptions exceeding 548 days. Patients were deemed to
be adherent if the MPr was at least 80%, a cutoff percentage
that is frequently cited in the literature.25
Operational Definition of Medication Burden
The medication burden was defined as the number of
unique drug products. The number of unique drug products
was determined by averaging the covered medications taken
n www.ajmc.com n?
n clinical n
ear regression analysis was used
for MPr, and logistic regression
analysis was used for adherence
as an indicator variable for an
MPr of at least 80%. Statistical
significance was set at P <.05.
This study was approved by
the University of Maryland In-
stitutional review board. The
board assigned an exempt status
to the research protocol.
Demographics and LL
The query of medical and
pharmacy claims found 23,813
patients with at least 1 ICD-9-
CM code for hypertension and
prescription claim for an LL
drug (Figure). Three hundred
twenty-six patients with 1 filled
LL drug throughout the study
period were excluded. A total
of 3058 patients (12.8%) with hypertension who had newly
started an LL drug met the inclusion and exclusion criteria.
Among the entire cohort on the index date, 2594 patients
(84.8%) filled a statin prescription, 190 patients (6.2%) filled a
fibrate prescription, and 175 patients (5.7%) filled a cholester-
ol absorption blocker prescription, while the remainder (3.3%
of patients) filled a niacin prescription, a bile acid sequestrant
prescription, or a combination prescription. The mean (SD)
copayment was $26.07 ($22.64) (range, $0.00-$299.64).
There were 1288 patients (42.1%) in group 1 and 1770
patients (57.9%) in group 2. both groups had a mean age of
about 55 years, with most patients aged 45 to 64 years, and
approximately 51% were male (Table 1). The medication
burden for patients in both groups was 2.9 medications, ex-
cluding the newly prescribed LL drug.
Effect of Medication Burden on Adherence
In multivariate analysis (Table 2), medication burden was
positively associated with persistence. Patients who had great-
er medication burden had longer persistence (hazard ratio for
discontinuation, 0.96; 95% confidence interval, 0.94-0.98;
P <.001). Likewise, patients who had greater medication bur-
den had higher MPr: an increase of 1 medication will increase
the MPr by 1.3 percentage points (P <.001). Moreover, using
the binary variable of an MPr of at least 80% as a threshold
chronically (>90 days) for which the days’ supply of the medi-
cation overlapped or was within 30 days after the end of the
days’ supply of the index prescription. This definition excludes
medications prescribed for acute treatment (eg, anti-infective
drugs and cough and cold drugs) during the study period
(eappendix available at www.ajmc.com). As an example, for
a patient who filled a prescription for simva statin on March
20, 2004 (index date), the patient’s medication burden would
be assessed as follows: lisinopril (20 mg) filled with a 30-day
supply on March 1, 2004, would count as a unique drug prod-
uct; alendronate sodium (70 mg) filled with a 90-day supply
on April 15, 2004, would count as a unique drug product; met-
formin (1000 mg) filled with a 30-day supply on March 20,
2004, would count as a unique drug product; and amoxicillin
(500 mg) with a 10-day supply on March 15, 2004, would not
count as a unique drug product. The medication burden for
the patient would be 3 medications.
Descriptive statistical analyses were performed for socio-
demographic and clinical characteristics of the entire cohort
and of the 2 subgroups. Multivariate regression models were
used to examine the unique associations between clinical or
demographic characteristics and adherence measures. Cox
proportional hazards model was used to assess persistence, lin-
n Figure. Timeline of Events.
HIV indicates human immunodeficiency virus; ICD-9-CM, International Classification of Diseases, Ninth
Revision, Clinical Modification; LL, lipid lowering.
VOL. 14, NO. 11
n THE AMErICAN JOUrNAL OF MANAGED CArE n?
Burden of lipid-lowering Drugs among Patients With Hypertension
for adherence, we found that having more concurrently pre-
scribed medicines leads to a higher probability of being ad-
herent: each increase in medication number raised the odds
by 0.10 (odds ratio for an MPr >80%, 1.10; 95% confidence
interval, 1.06-1.14; P <.001) (data not shown).
Other Predictors of Adherence
The mean (SD) duration of persistence was 288.9 (210.1)
days (range, 6-548 days), with a mean (SD) MPr of 76.9%
(25.5%) (range, 5.8%-100.0%) (Table 1). Among the study
cohort, 56.9% were deemed adherent based on an MPr of at
The mean duration of persistence for group 1 was 263.1
days compared with 307.7 days for group 2 (Table 1). The
mean MPr was 72.1% for group 1 compared with 80.3% for
group 2. A total of 47.8% of patients in group 1 had an MPr
of at least 80% compared with 63.5% of patients in group 2.
Men had longer persistence than women (hazard ratio
for discontinuation, 0.85; P <.001), as summarized in Table
2. Group 1 had shorter persistence than group 2 (hazard ratio
for discontinuation, 1.27; P <.001). There were no significant
effects of age on persistence. Patients taking statin drugs did
not have improved persistence compared with patients taking
other LL classes of drugs. Similarly, men had higher MPrs and
were more adherent (MPr, >80%) than women (P = .003 and
P = .002, respectively) (data not shown). Group 1 had lower
MPrs and were less likely to be adherent (MPr, >80%) than
group 2 (P <.001 for both).
Our study evaluated the effect of medication burden on
persistence of newly added LL drugs among patients with
hypertension in a managed care population. In this cohort
of patients, the mean persistence of 9.63 months seems
poor, as this was only 53.5% of the study period. We found
that patients with longer medication lists did not have
lower medication persistence or adherence to newly started
chronic therapy. In fact, patients taking more medicines
had longer persistence with LL therapy and tended to have
higher MPrs. In addition, patients who did not change
LL drug or dosage (ie, they remained on their original LL
regimen) had longer persistence and were more adherent
(MPr, >80%) compared with those who changed or added
an LL drug.
Previous studies have shown conflicting results about the
relationship between medication burden and adherence. The
literature seems almost equally divided on the point. Three
n Table 1. Study Cohort Demographics
(N = 3058)
Mean (SD)55.2 (10.6)55.1 (10.6) 55.3 (10.7).52
35-4412.4 12.1 12.6—
55-64 36.7 36.736.8—
Male sex, %
Statin, %84.880.488.0 <.001
Adherence measure, mean (SD)
Persistence, d288.9 (210.1) 263.1 (207 .0)307 .7 (210.4) <.001
MPR, %76.9 (25.5)72.1 (25.3)80.3 (21.5)<.001
Adherence (MPR, ≥80%), %56.9 (49.5)47 .8 (50.0)63.5 (48.1)<.001
non-LL therapy, mean (SD), no.2.9 (2.5)2.9 (2.5)2.9 (2.4) .77
LL indicates lipid lowering; MPR, medication possession ratio.
n www.ajmc.com n?
n clinical n
studies15-17 support a positive relationship, while 3 other stud-
ies18-20 support a negative relationship. Our study supports the
finding that adherence tends to increase among patients tak-
ing multiple medications. Grant et al,15 who studied a similar
patient population, found that patients with more concur-
rently prescribed medications (at the time of initiation of
statin therapy and at the time of their last recorded statin
refill) had longer persistence with statin therapy over time. In
a retrospective study of adherence (calculated as 1 minus the
number of days without drug, divided by the total number of
days in the study) among a high-risk Veterans Affairs popula-
tion of 1054 patients, billups et al16 reported better adher-
ence among patients taking more concurrent medications.
Another study17 that used self-reported survey questions to
assess adherence (calculated based on prescription fill dates
and number of days supplied) among 367 patients from an
acute care ward and an on-site lipid clinic at a hospital in
Canada found that nonadherent patients (<80%) took fewer
prescription medications compared with adherent subjects
(4.1 vs 5.9 medications).
In contrast to our results, 3 other large retrospective cohort
studies18-20 of patients receiving concomitant LL therapies
found that increasing medication burden was associated with
a decrease in LL drug adherence. Chapman et al18 measured
the proportion of days covered by a given drug among 8406
patients enrolled in a managed care orga-
nization. The authors found that, as the
number of other prescribed medications
decreased, the likelihood of adherence
to concomitant LL therapy increased.18
Two studies conducted by benner et
al19 and by Avorn et al20 have overlap-
ping populations with similar findings.
benner et al19 measured the proportion
of days covered among an older New
Jersey Medicaid population of 34,501
patients >65 years. These patients were
prescribed a mean of 9.2 medications
in the prior year. Significant subopti-
mal adherence over time was observed
only in patients prescribed 11 or more
medicines in the prior year. Avorn et
al20 focused on persistence (proportion
of days) as the measure of LL drug ad-
herence among a cohort of New Jersey
and Quebec Medicaid patients 65 years
and older. Patients in this cohort were
prescribed 1 to 16 medications or more
than 16 medications in the prior year.
The authors found that patients with
prescriptions for more than 16 drug products per year were
less likely to continue to fill prescriptions for LL drugs.
According to the health belief model,26 patients who be-
lieve that they are in poor health (which could be the case for
patients taking multiple medications) are more likely to take
the necessary steps to monitor their health and to take medi-
cations as prescribed. Therefore, patients who are prescribed
multiple medications believe that they are more responsible
for their disease state and are more adherent to their pre-
scribed medications compared with healthier patients.16 A
possible explanation for the difference between our study re-
sults versus other studies that found conflicting results could
be that LL drug adherence was better with higher medication
burden up to a certain limit, beyond which adherence tends
to be poorer. In the study by benner et al,19 the authors found
that patients who were prescribed 11 or more medicines had
suboptimal adherence compared with those who were pre-
scribed fewer than 11 medicines. The patients in the study by
benner et al19 had a mean of 9.2 medications compared with
a mean of 2.9 medications among the patients in our study.
Patients with the highest medication burden may be consid-
erably sicker, and the burden of the illness may be too much
for them, further decreasing medication adherence.15
According to a study27 of 4068 older outpatients newly
starting antihypertensive therapy, older age was associated
n Table 2. Multivariate Regression Analysis of Predictors of Discontinua-
tion of Lipid-Lowering Therapy
(95% Confidence Interval)
18-34 1 [Reference]
35-440.91 (0.69-1.19) .48
45-540.83 (0.64-1.08) .16
55-640.79 (0.61-1.03) .07
0.78 (0.59-1.03) .08
0.98 (0.72-1.35) .91
Male 0.85 (0.78-0.92)<.001
Female 1 [Reference]
Statin1.00 (0.89-1.12) .98
nonstatin 1 [Reference] —
2 1 [Reference]—
VOL. 14, NO. 11
n THE AMErICAN JOUrNAL OF MANAGED CArE n?
Burden of lipid-lowering Drugs among Patients With Hypertension
with good adherence (>80%). In
our study, age was not a significant
predictor of persistence, similar to
findings reported by other research-
ers.15,16 Some studies15,16,27 have found
no relationship between adherence
to antihypertensive therapy and
sex. However, our study found that
women were less persistent than
men, similar to findings reported by
Chapman et al.18 The associations of
age and sex with adherence to statin therapy were evalu-
ated in a retrospective study.28 The study used claims data
from a large national employment-based independent prac-
tice association database. Subjects (n = 21,239) were at high
risk of coronary heart disease and had filled a prescription
for statin therapy. Patient data were captured for 12 months
before and 12 months after the index date (first statin pre-
scription fill). Adherence was defined as an adherence ratio
of at least 80% or a daily dose of medication available for at
least 80% of the days in the study period. According to this
study, older subjects were 1.03 times as likely to be adherent
compared with younger subjects, and men were 1.42 times
as likely to be adherent to statin therapy compared with
women. Differences in adherence rates between respective
cohorts were statistically significant. The authors noted that
there were limited published data that evaluated the effect
of medication adherence to an index drug when the index
drug is changed or another drug is added. Our study found
that there was significantly higher persistence and adherence
among patients who did not change their LL drug compared
with those who changed or added an LL drug.
Several limitations of our study should be noted. An in-
herent limitation of this study is that our methods relied on
ICD-9-CM coding first in identifying patients with hyper-
tension and then in identifying patients with certain comor-
bid illnesses to be excluded (eg, depression and HIV). This
point has the following implications: (1) we did not require
members to have multiple medical claims for any of the med-
ical diagnoses, so false-positive classification is possible; and
(2) as with all medical claims, we had no way to evaluate the
accuracy of the coding, which may be incomplete. Our re-
sults may not be comparable to those of other studies because
we excluded patients with certain medical conditions (eg,
schizophrenia, depression, bipolar disorder, mental retarda-
tion) that may affect adherence rates. Another limitation
is that physician prescribing of LL therapy was determined
from prescription refill claims. Although the use of prescrip-
tion refill claims has been validated as effective, it has some
disadvantages. We are unable to ascertain if a patient had a
change in dosage and did not have a new prescription for
that strength (eg, took half a tablet). Therefore, adherence
would be underestimated or overestimated in those patients.
In addition, evaluating refill records for medication burden
measures the timeliness of refills and does not indicate if the
dispensed drug was actually taken by the patient. As a result,
overestimation of adherence occurs in patients who fill their
prescriptions on time but who are not taking the drugs as
prescribed or as often as would be expected based on the
refill pattern. In addition, the adherence parameters could
have been affected by the use of drug samples obtained from
physician offices, which would result in underestimates of
adherence. In addition, some variables (eg, visit frequency,
hospitalizations, use of multiple providers) were not captured
in our analysis that could have affected adherence. Another
limitation is that nonprescription medications that could be
taken chronically are not accounted for in the claims anal-
ysis. Also, the prescription refills do not provide informa-
tion pertaining to the directions or indications for the drug.
Therefore, a patient who fills a 30-day supply of a particular
drug with directions to take 1 tablet every other day could be
mistaken as nonadherent if the prescription was not refilled
within 30 days. Similarly, some patients may have been told
by the physician to discontinue drug therapy because they
developed an adverse effect or because of ineffective drug
therapy, and they too may have mistakenly been considered
Clinicians managing patients with CVD often struggle
with the effect of adding additional therapies to regimens of
patients who already have complicated medication regimens.
This study demonstrates that medication burden does not
reduce adherence or persistence. Clinicians need not be as
concerned regarding patients with a mean medication bur-
den of 2.9 medications, as the effect of increased medication
burden on adherence was positive. Once LL therapy has been
added, more attention should focus on patients who have
Cardiovascular risk factors such as hypertension and dyslipidemia commonly coexist, re-
quiring the patient to use multiple drug therapies to achieve optimal control according to
n Clinicians managing patients often struggle with adding more drugs to regimens of pa-
tients who already have complicated medication regimens.
n This study describes the effect of medication burden on persistent use of newly added
lipid-lowering drugs among patients with hypertension.
n Patients with higher medication burden had greater adherence to newly added lipid-low-
ering therapy; therefore, medication burden should not deter clinicians from adding lipid-
716 Download full-text
n www.ajmc.com n?
n clinical n
changes to their LL regimen, as they were less persistent and
adherent compared with patients maintaining the same LL
prescription. Given the continued trend of more aggressive
management of chronic medical conditions, further research
should be conducted to assess the full range of the relation-
ship between medication burden and adherence among pa-
tients with chronic disease states.
We thank Anne G. Wood, MbA, for her assistance with obtaining medi-
cal and pharmacy claims data.
Author Affiliations: From the School of Pharmacy (TAr, CEC, JW,
FTS), University of Maryland, baltimore; PosiHealth (CEC), baltimore, MD;
and CareFirst blueCross blueShield (HYL), baltimore, MD. Dr robertson is
now with Express Scripts, bloomington, MN.
Funding Source: None reported.
Author Disclosure: The authors (TAr, JW, FTS, HYL) report no rela-
tionship or financial interest with any entity that would pose a conflict of
interest with the subject matter of this article. Dr Cooke is a former employee
of Pfizer, Inc, and reports owning stock in that company.
Authorship Information: Concept and design (TAr, CEC, FTS, HYL);
acquisition of data (HYL); analysis and interpretation of data (TAr, CEC,
JW, FTS); drafting of the manuscript (TAr); critical revision of the manu-
script for important intellectual content (CEC, JW, FTS, HYL); statistical
analysis (TAr, JW, FTS); administrative, technical, or logistic support (TAr,
HYL); and supervision (TAr, CEC, FTS).
Address correspondence to: Teisha A. robertson, PharmD, MbA, PO
box 6893, Largo, MD 20774. E-mail: email@example.com.
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