Patient Preference and Adherence Dovepress

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ORIGINAL RESEARCH

Factors Associated With Medication Adherence

In Elderly Retired Outpatients In São Paulo,
Brazil
This article was published in the following Dove Press journal:
Patient Preference and Adherence

Juliana Martins Ribeiro Valassi1 Objective: To evaluate medication adherence and associated socioeconomic factors in
Nelson Carvas Junior1 elderly Brazilians.
Mirian Matsura Shirassu1 Methodology: This observational study was conducted with 159 elderly retired in an
Kaleo Eduardo de Paula1 outpatient clinic in the city of São Paulo. Treatment adherence was assessed with the
questions from the Morisky Green Levine Medication Adherence Questionnaire, and med-
Elena R Atkinson 2
ications were classified using the Anatomical Therapeutic Chemical system. Statistical tests
Marcia Kiyomi Koike 1,3
and adjusted Poisson regression models were used to analyze variables.
1
Health Sciences Department, Institute Results: The study population was mostly female (67.5%), had an average age of, and took
for Medical Assistance to State Public
Servants, São Paulo, Brazil; 2Fundación an average of 6.5 medications per day. The most commonly used drugs were agents acting on
IDEA, Mexico City, Mexico; 3Emergency the renin-angiotensin system (67.9%), statins (62.3%), antithrombotic agents (48.4%), and
Medicine Department, Medical School, biguanides (37.1%) for the treatment of hypertension (76.7%), dyslipidemia (54.1%), and
University of São Paulo, São Paulo, Brazil
diabetes (47.8%). The rate of adherence was below 60% in the groups of participants that
were analyzed except for the high household income category, which had a rate of 75.8%.
Conclusion: Medication adherence among the elderly was low in all categories except for
the high household income category, a relevant finding that will help to understand medica-
tion adherence patterns in elderly Brazilians.
Keywords: medication adherence, aged, geriatrics, polypharmacy, drug therapy, socioeconomic
factors

Introduction
Transformative advances in healthcare, especially in pharmacology, have contrib-
uted to significantly increased life expectancy worldwide. However, the people for
whom these medications are designed do not always consume them in accordance
with clinical indications. The elderly make up a population of particular interest in
medication adherence research as—in addition to consuming the highest proportion
of medication per capita—they are beginning to occupy a more substantial propor-
tion of the total population. Additionally, older adults with chronic conditions are at
a higher risk of suffering damaging health consequences caused by lack of com-
Correspondence: Marcia Kiyomi Koike pliance with drug indications.1,2 Issues with adherence mainly occur among elderly
Programa de Pós-Graduação em Ciências
da Saúde. Instituto de Assistência Médica people who use five or more drugs per day, a situation known as polypharmacy.
ao Servidor Público Estadual (IAMSPE), Recent publications demonstrate that most older adults are unable to take multiple
Brasil Av. Ibirapuera, 981 - 2º andar, Vila
Clementino, São Paulo/SP CEP: 04029-000, simultaneous prescriptions adequately.3,4
Brazil
Elderly people (above the age of 60) currently make up approximately 14% of
Tel +55 11 9 9964-8421
Email mkkoike17@gmail.com the Brazilian population, and this proportion is projected to increase to almost 30%

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by 2050.5 In addition to an increase in this population, system still lacks comprehensive public policy on medica-
medication use in this country is expected to increase, tion distribution.2 Accordingly, this study was designed to
meaning that medication adherence is, therefore, a signifi- provide evidence on medication adherence and related
cant research topic for Brazil. The nation’s socialized socioeconomic factors among elderly retirees in an out-
public healthcare system provides an additional incentive patient clinic in São Paulo. It was conducted in the city of
to better understand the factors that impede senior citizens São Paulo, as it is the largest and most populated city in
with chronic disease from taking their medications as the country and also has a large population of elderly
indicated, as lack of adherence can increase healthcare residents.
costs.1,6,7 This document will use the World Health
Organization’s definition of adherence, which is: “the
Methods
extent to which a person’s behavior—taking medication,
following a diet, and/or executing lifestyle changes—cor- Study Design, Setting, And Population
responds with agreed recommendations from a health care This cross-sectional study was carried out in elderly retiree
provider.”8 outpatients of the cardiology and endocrinology depart-
An observational study by Uchmanowicz9 using this ments at a public hospital in São Paulo. These two out-
scale found higher rates of adherence in participants with patient clinics were chosen because of their high volume
higher educational achievement and family support, indicat- of geriatric patients with chronic conditions and without
ing a possible relationship between socioeconomic factors cognitive decline or severe acute disease. The clinics pro-
and medication, albeit one that is not widely studied.10 vided enough patients for the sample size (159 patients) to
Previous studies on medication adherence in elderly people be representative of the broader population of older retired
in developing countries, especially in the context of poly- adults in São Paulo. Data collection occurred between
pharmacy, have previously incorporated socioeconomic June 2016 and July 2017.
variables. However, very few studies explicitly state that All elderly patients requesting medical attention at
this is the primary motive for the study. Another issue is the these clinics during the data collection period were
lack of ability to compare adherence findings between dif- approached and asked if they wished to participate in the
ferent countries and regions. Specific instruments—such as study. If the patient expressed interest, the study design
the Anatomical Therapeutic Chemistry (ATC)11 classifica- and purpose was explained in plain language, and the
tion and the Morisky Green Levine Medication Adherence patient signed an informed consent form to agree to their
Questionnaire (MGLQ)12—have been validated to measure official participation in the research study. Inclusion cri-
medication use and adherence, respectively. The MGLQ is teria included being a retired adult between the age of 60
one of the most widely used questionnaires in Brazilian and 75 and taking at least two medications per day.
research on medication adherence13,14 and was selected Retirement was defined as receiving a monthly pension
for this study for this reason and also because it provides from the government; in Brazil, men can receive a govern-
standardized results to compare adherence across cultures ment pension once they turn 65 and women, once they
and countries. Most studies on adherence in Brazil are not turn 60, or any individual can receive a pension for work-
published in English, and the MGLQ will allow for our ing a stipulated number of years or for work-related inju-
results to reach a wider international audience. ries/disabilities. The age limit to define the elderly was set
Brazil has numerous medical, social, and economic per World Health Organization guidelines, which define
reasons for requiring a study on medication adherence in elderly people as individuals over the age of 60 in lesser-
the elderly. The nation is a middle-income country with developed regions.6 An estimated 77% of Brazilians with
high levels of inequality—especially among older adults— dementia have not been diagnosed,17,18 and therefore, all
that is going through a demographic transition. Brazil is patients over the age of 75 were excluded. This was to
also one of the countries with the highest rates of poly- avoid ethical issues and to avoid introducing recall bias
pharmacy in the world, along with the United States, into the study. The only other exclusion criterion was
Sweden, India, the United Kingdom, and China.15,16 insufficient mental capacity to respond to questionnaire
Chronic diseases are an increasing concern in Brazil, and items. To ensure the complete absence of memory issues,
suboptimal medication adherence is thought to be imped- research personnel also administered the Mini-Mental
ing chronic disease control. The socialized public health State Examination (MMSE),19 an easy-to-administer and

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widely-used instrument. The MMSE is a screening test for as “not adherent” and participants with a score of 3 or 4
possible cognitive decline, in which a score of 24 or lower points were classified as “adherent.”
suggests cognitive decline.19 In this study, two potential
participants had a score below 25 and were therefore Anatomical Therapeutic Chemical
excluded.
Classification System
We used the ATC to analyze the medications our study
Questionnaire: General Information participants used. With the ATC methodology, drugs are
This study used the MGLQ and ATC instruments: both divided into groups at their respective sub-levels based on
questionnaires had been previously translated into their mechanisms of action, chemical properties, therapeu-
Portuguese and validated. A pharmacy student and two tic actions, and kinetic and dynamics classifications. The
nurses administered the questionnaires in face-to-face ATC’s standardization allows for comparable statistical
interviews in Portuguese in approximately 40 min sessions studies, which then allows for improved comparations
on the day of the respective patient’s appointment. All and measurements in drug development and utilization.13
patient-reported information was corroborated with patient
files to avoid bias. Sample Size
Socioeconomic variables were divided into categories: The sample size was calculated with the 6th edition of the
marital status was divided into married or other (unmarried, EpiInfo program using statistics on the number of retirees
divorced, or widowed); educational level was divided into in São Paulo (53.7%), older adults with dementia (13%),
low level of schooling (illiterate or incomplete elementary and individuals in polypharmacy regimens. These percen-
school), some schooling (complete elementary school or tages were used to calculate the proportion of retirees both
incomplete secondary school), and complete basic educa- in treatment and in follow-up, subtracting the estimated
tion (complete secondary education or above); housing was number of retirees with dementia. The formula was
divided into other (inherited house, renting, or living with applied to the final value and multiplied by 1.18, estimat-
children) and home-owner; reason for retirement was ing a refusal rate of 10% and an incompletion rate of 5%.
divided into retirement by age, time of service, or disability; A total of 167 elderly outpatients were approached, of
retirement times were dichotomized as fewer than 10 years which eight patients were excluded for not fulfilling inclu-
or over 10 years. Household income was divided into low sion/exclusion criteria or for filling out the questionnaires
income (below two minimum monthly salaries) and high incorrectly. Therefore, the final sample size was 159
income (above two minimum monthly salaries). As a refer- participants.
ence, the minimum monthly salary in 2017 was BRL 937,
or approximately USD 250. Brazilians are generally uncom-
fortable reporting their annual income to strangers and this
Statistical Analysis
The data were first described with descriptive statistics,
was a division that most participants were familiar with and
including mean and standard deviation, absolute numbers,
comfortable with reporting.
and relative percentages for quantitative variables. A
Shapiro-Wilk test and Levene test were run to verify assump-
Morisky, Green And Levine Medication tions of normal distribution and homogeneity of variances,
Adherence Questionnaire both for age (W = 0.961; p < 0.001/F (49) = 0.901; p = 0.645)
Adherence to drug treatment was assessed using the ques- and for the number of medications used (W = 0.959;
tions contained in the MGLQ, a test developed in the P = 0.0001/F (49) = 1.047; P = 0.873). A Mann–Whitney
United States and validated for the Portuguese language. test was used to compare ages and numbers of medications.
The test is easy to understand and consists of four yes-or- Pearson Chi-square tests were used to compare marital status,
no questions that identify attitudes towards drug therapy education levels, household income, housing, retirement
and behaviors involved in taking medication. Each “yes” time, and retirement type between the sexes. The association
receives a score of zero (0), and each “no” receives a score between the variables and adherence to medication use on the
of one (1). If all the answers are “no,” the score is 4, and if MGLQ was tested using Poisson regression models adjusted
all the answers are “yes,” it is 0. In our research, partici- with robust variance. All analyses were performed in the
pants with a score between 0 and 2 points were classified version 3.4.2 of R using the prevalence and sandwich

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packages. The level of significance adopted for all analyses age of the participants was 68.30 ± 4.0 years, 80% were
was p <0.05. retired after meeting the minimum number of years worked,
and 67% had been retired for over ten years (Table 1).
Ethics The most common chronic diseases were: systemic
The Research Ethics Committee of IAMSPE approved the arterial hypertension (76.7%), dyslipidemias (54.1%), dia-
study, with reference number 1.598.277. All participants betes/hyperglycemia (47.8%), and gastro-esophageal reflux
received a clear, plain-language summary of the study disease (GERD, 38%), as shown in Table 2. Table 3 pre-
design, benefits, and risks and then signed voluntary sents the medicines that the elderly used, divided into
informed consent forms. As this study was purely observa- generic denominations of the ATC classification. The most
tional and questionnaire-based, the risk to participants was commonly used agents were those that act on the renin-
considered low. angiotensin system (67.9%), inhibitors of the enzyme 3-
hydroxy-3-methyl-glutaryl-CoA reductase—also known as
Results statins—(62.3%), antithrombotic agents (48.4%), medicines
A total of 167 elderly outpatients were approached, of which for the treatment of peptic ulcers (36.5%), and biguanides
two patients refused participation and eight patients did not (37.1%). Many of the participants were on polypharmacy
fulfill inclusion/exclusion criteria or fill out the question- regimens, taking an average of 6.5 medications per day.
naires correctly. Therefore, the total final sample size was The results of adherence measured with the MGLQ and
159 participants. The sample was predominantly female analyzed with Poisson regression analysis are presented in
(68.5%), highly educated (50.3%), had above-average Table 4. The medication adherence rate was below 60% in
income (60.5%), and were home-owners (95%). The average all of the socioeconomic categories that were analyzed,

Table 1 General Characteristics Of The Sample By Patient Gender

Variables Female (n = 109) Male (n = 50) Total (n = 159) P Value

Age (years) 68.3 ± 4.0 684 ± 4.2 68.3 ± 4.0 0.859

Medications used per day 6.5 ± 2.7 6.4 ± 2.7 6.5 ± 2.7 0.952

Variables N (%) N (%) N (%) P Value

Marital status <0.001

Married 58 (53.2) 44 (88.0) 102 (64.2)
Others 51 (46.8) 6 (12.0) 57 (35.8)

Educational level 0.855

Low 33 (30.3) 13 (26) 46 (28.9)
Medium 22 (20.2) 11 (22) 33 (20.8)
High 54 (49.5) 26 (52) 80 (50.3)

Household income 0.315

Below two minimum salaries 47 (42.6) 17 (32.7) 64 (39.5)
Above two minimum salaries 62 (57.4) 33 (67.3) 95 (60.5)

Type of residence 0.442

Owner-occupied 105 (96.3) 46 (92.0) 151 (95.0)
Others 4 (3.7) 4 (8.0) 8 (5.0)

Retirement time 0.341

Less than ten years 67 (61.5) 26 (52.0) 93 (58.5)
More than ten years 42 (38.5) 24 (48.0) 66 (41.5)

Type of retirement 0.293

Age 18 (16.5) 4 (8.0) 22 (13.8)
Number of years worked 80 (73.4) 42 (84.0) 122 (76.7)
Disability/other 11 (10.1) 4 (8.0) 15 (9.4)

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Table 2 Frequency Distribution Of Morbidities By Patient Gender

Morbidity Female (n = 109) Male (n = 50) Total (n = 159)
n (%) n (%) n (%)

Systemic arterial hypertension 82 (75.2) 40 (80.0) 122 (76.7)

Dyslipidemia 62 (56.9) 24 (48.0) 86 (54.1)
Diabetes mellitus 48 (44.0) 28 (56.0) 76 (47.8)
GERD 16 (14.7) 6 (12.0) 22 (38.0)
Hypothyroidism 36 (33.0) 8 (16.0) 44 (27.7)
Arthrosis 27 (24.8) 12 (24.0) 39 (24.5)
Arrhythmia 6 (5.5) 10 (20.0) 16 (10.1)
Depression 13 (11.9) 3 (6.0) 16 (10.1)
Coronary insufficiency 11 (10.1) 5 (10.0) 16 (10.1)
Osteopenia 14 (12.8) 1 (2.0) 13 (8.2)
Arthritis 9 (8.3) 2 (4.0) 11 (6.9)
Hepatic steatosis 8 (7.3) 1 (2.0) 9 (5.7)
Gastritis 9 (8.3) 0 (0) 9 (5.7)
Glaucoma 7 (6.4) 2 (4.0) 9 (5.7)
Asthma 6 (5.5) 2 (4.0) 8 (5.0)
Coronary arterial disease 6 (5.5) 2 (4.0) 8 (5.0)
Osteoporosis 7 (6.4) 1 (2.0) 8 (5.0)
Cataracts 5 (4.6) 2 (4.0) 7 (4.4)
Chronic atrial fibrillation 6 (5.5) 1 (2.0) 7 (4.4)
Chronic renal insufficiency 4 (3.7) 3 (6.0) 7 (4.4)
Prostatic hyperplasia 1 (0.9) 5 (10.0) 6 (3.8)
Hyperthyroidism 3 (2.8) 1 (2.0) 4 (2.5)
Lower back pain 3 (2.8) 1 (2.0) 4 (2.5)
Varicose veins 4 (3.7) 0 (0) 4 (2.5)
Cardiac valvulopathy 2 (1.8) 2 (4.0) 4 (2.5)
Cerebral vascular accident 3 (2.8) 0 (0) 3 (1.9)
COPD 2 (1.8) 1 (2.0) 3 (1.9)
Labyrinthitis 3 (2.8) 0 (0) 3 (1.9)
Alzheimer’s disease 1 (0.9) 1 (2.0) 2 (1.3)
Ischemic stroke 1 (0.9) 1 (2.0) 2 (1.3)
Gout 1 (0.9) 1 (2.0) 2 (1.3)
Inguinal hernia 1 (0.9) 1 (2.0) 2 (1.3)
Hypoparathyroidism 2 (1.8) 0 (0) 2 (1.3)
Gall stones 1 (0.9) 0 (0) 1 (0.6)
Bipolar Disorder 1 (0.9) 0 (0) 1 (0.6)
Diverticulitis 1 (0.9) 0 (0) 1 (0.6)
Epilepsy 0 (0) 1 (2.0) 1 (0.6)
Congestive cardiac insufficiency 1 (0.9) 0 (0) 1 (0.6)
Gastric reflux 1 (0.9) 0 (0) 1 (0.6)
Abbreviations: GERD, gastroesophageal reflux disease; COPD, chronic obstructive pulmonary disease.

with no statistically significant difference between groups The study population mostly consisted of women with high
except in the high-household-income cohort, where the levels of education who were homeowners with a household
prevalence of adherence was 75.8%. income considered high for elderly Brazilians. The mean age
of the participants was 68, and most had retired after having
Discussion worked the required number of years. As this research was
This study evaluated the level of medication adherence carried out in a large urban center, it contrasts with other
among retired elderly participants and related socioeconomic studies in rural areas, where elderly residents live in more
factors in a public outpatient clinic in the city of São Paulo. varied socioeconomic conditions.

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Table 3 Distribution Of Frequencies Of Medications Used Under state of Minas Gerais, found that adherence was 47% in
Generic Names – Anatomical Therapeutic Chemistry Classification 279 elderly participants, most of whom were low-income
Anatomical Therapeutic Chemistry N (%) women on polypharmacy regimens.7,20,21
Classification The most common chronic morbidities in treatment in
A02B – Medications for the treatment of peptic ulcers 58 36.5 our study participants were systemic arterial hypertension,
A03 – Propulsive agents 10 6.3 dyslipidemia, diabetes mellitus/hyperglycemia, and gastro-
A10A – Insulin and analogs 27 17 esophageal reflux disease. This distribution of chronic
A10BA – Biguanides 59 37.1 conditions is in line with Stopa’s22 findings: a considerable
A10BB – Sulfonylureas 40 25.2
increase in the incidence of these pathologies in São Paulo
A10BG – Thiazolidinediones 14 8.8
from 2003 to 2015 with low adherence to recommended
B01 – Antithrombotic agents 77 48.4
C01B – Antiarrhythmics 11 6.9 behavioral changes. It is widely known that both beha-
C01D – Vasodilators used in heart disease 17 10.7 vioral changes (improvements in diet and lifestyle) and
C01E – Other cardiac preparations 2 1.3 pharmacological treatments are necessary to prevent and
C02A – Central acting alpha-adrenergic antagonist 2 1.3 control chronic disease. However, Brazilians tend to prefer
C02C – Peripheral alpha-adrenergic antagonist 2 1.3
pharmacological treatments, as they are easier to access,
C02D – Direct vasodilators 7 4.4
have a more evident therapeutic efficacy, and are simpler
C03A – Thiazide diuretics 45 28.3
C03C – Loop diuretics 16 10.1 to take than making lifestyle changes. This difficulty in
C03D – Potassium-sparing diuretics 6 3.8 promoting lifestyle changes has been evidenced by low
C07 – Beta-blocker agents 66 41.5 adherence to non-medication treatments as an auxiliary to
C08 – Calcium channel blockers 31 19.5 pharmacological treatment.20,21,23–30
C09 – Agents acting on the renin-angiotensin system 107 67.3
The most used medications in this study, organized by
C10AA – 3-hydroxy-3-methyl-glutaryl-CoA reductase 99 62.3
inhibitors (statins)
ATC classification, were agents acting on the renin-angioten-
C10AB – Fibrates 2 1.3 sin system, statins, antithrombotic agents, and biguanides.
H02 – Corticosteroids for systemic use 2 1.3 These drugs are used to treat the most prevalent diseases
H03A – Thyroid hormones 46 28.9 among the elderly, such as hypertension, dyslipidemia, and
M01A – Non-steroidal anti-inflammatory and anti- 7 4.4 diabetes/hyperglycemia, which are the very same diseases
rheumatic agents
that are predominant in our population.22,23,25–30 The ATC
M03BX – Other central-acting agents 3 1.9
N02 – Analgesics 4 2.5
classification used in this study is an important contribution
N02A – Opioids 1 0.6 to the literature, as the study results are standardized inter-
N02B – Other analgesics and antipyretics 18 11.3 nationally—a rarity in Brazilian publications. Using this
N03AE – Benzodiazepines 1 0.6 classification, we found an average use of 6.5 medications
N05A – Antipsychotics 4 2.5 per day, which meets the definition of polypharmacy, a
N05BA – Benzodiazepines 1 0.6
situation also found in other Brazilian and international arti-
N05C – Hypnotics and sedatives 1 0.6
cles on the subject.16,25
N06A – Antidepressants 5 3.1
N06AB – Selective serotonin reuptake inhibitors 17 10.7 In our study, the prevalence of adherence measured
S01E – Antiglaucoma and miotic preparations 5 3.1 with the MGLQ questions was below 60% in all cate-
gories, except for those in the high household income
category (75.8%). The literature considers adherence
Previous publications in the literature have suggested a rates between 40 and 60% to be low.8,12,31,32 Menditto et
possible relationship between low adherence and socio- al.5 carried out an exploratory study of 39,000 elderly
economic factors. One study carried out in 934 elderly patients in three European countries using medication
residents of the Brazilian state of Goiás (predominantly registries to calculate non-adherence. The study authors
widows and low-income earners) found a prevalence of found prevalences of non-adherence to the use of antihy-
adherence of 24% for those on polypharmacy regimens. perlipidemic drugs to be 36.87% in Ireland, 60.93% in
Another Brazilian study, conducted in primarily low- Spain, and 68.44% in Italy, with general medication adher-
income elderly people in the state of Rio Grande do Sul, ence rates of 50% in the three countries. Lee25 conducted
found a prevalence of low adherence among a third of the an observational study of 1,154 (predominantly elderly)
1,598 people interviewed. A third Brazilian study, in the hypertensive individuals in Hong Kong, finding low or

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Table 4 Prevalence Of Medication Adherence According To Participant Characteristics

Variable N Prevalence (%) P Value PR (IC95%)

Sex
Female 52 47.7 (38.4–57.1) 1
Male 23 46.0 (32.2–59.8) 0.842 0.96 (0.67–1.38)

Educational level
Low 20 43.5 (29.2–57.8) 1
Medium 14 42.4 (25.6–59.3) 0.926 0.98 (0.58–1.63)
High 41 51.3 (40.3–62.2) 0.412 1.18 (0.80–1.75)

Residence
Other 3 37.5 (3.4–71.0) 1
Owner-occupied 72 47.7 (39.7–55.6) 0.605 1.27 (0.51–3.16)

Household income
Below two minimum salaries 26 41.9 (29.7–54.2) 1
Above 2 minimum salaries 72 75.8 (67.2–84.4) 0.249 1.23 (0.87–1.75)

Retirement time
Up to 10 years 40 43.0 (32.9–53.1) 1
More than 10 years 35 21.1 (14.9–27.3) 0.208 1.23 (0.89–1.71)

Marital status
Married 49 45.6 (32.7–57.7) 1
Others 26 45.6 (32.7–58.5) 0.771 0.95 (0.67–1.35)

Type of retirement
By age 13 59.1 (38.5–79.6) 1
By time of service 57 46.7 (37.9–55.6) 0.245 0.79 (0.53–1.18)
By disability/pension 5 33.3 (9.5–57.2) 0.159 0.56 (0.26–1.25)
Abbreviations: PR, Prevalence ratio of medication adherence, adjusted by Poisson regression with robust variance; 95% CI, 95% confidence intervals.

poor treatment adherence on the Morisky Medication other healthcare professionals, such as pharmacists and
Adherence Scale (MMAS). These studies all show low nurses), as they have positive results on adherence.23–25
adherence rates in a variety of countries with different The role of family support in treatment adherence—
populational indices, socioeconomic conditions, and gov- although not evaluated formally in this study—has
erning styles. The results show that low adherence among emerged as a likely mediating factor between physicians
the elderly is a global public health problem in need of and their elderly patients, even those with preserved
effective solutions. cognitive ability. As adherence has been found to be
The proportion of low adherence found in our study in higher in older adults with higher household incomes,
almost all of the analyzed categories, except the high-income there may be a relationship between high income and
category, suggests a possible relationship between socioeco- adequate family support. Therefore, professionals could
nomic factors and adherence. During this study, we also work together with families in all socioeconomic cate-
observed a lack of drug assistance at the outpatient level. gories to seek solutions for correct medication use.
That is, doctors are the only providers who are responsible Comprehensive medication support could help avoid the
for advising elderly patients on medication use, and they only preventable risks that are associated with low adherence
have limited office visit hours to provide this patient educa- and resultant treatment ineffectiveness, such as adverse
tion. For elderly insulin-dependent diabetic patients in endo- reactions, hospitalizations, and even deaths.31–35 Recent
crinology outpatient clinics, nurses are responsible for studies suggest that educational programs, monitoring,
teaching them the correct use of glucometers and insulin and gerontological follow-up could be facilitating factors.
application techniques. International literature recommends These, together with family support, could be fruitful
using a comprehensive and team-based approach (involving areas for new research in elderly patients.7,27–30,32,33,36

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The positive association found in this study between significant limitation is that we excluded potential partici-
household income and medication adherence is an impor- pants over the age of 75 from this study. We initially did
tant advancement in this research field, especially consid- this to avoid introducing memory bias into the research
ering the scarcity of Brazilian publications on this topic. study and to avoid inadvertently diagnosing dementia,
As Brazil moves through a demographic transition and which would have raised severe ethical issues. However,
gains an increased proportion of older adults, the nation we recognize that this may have limited our study size and
will most likely see an increase in medication consumption the applicability of these results to older geriatric patients;
in a country that is already known for an above-average therefore, we recommend that, instead of setting age lim-
prevalence of polypharmacy. Polypharmacy coupled with its, future studies should apply the MMSE or other similar
marked social inequality and high poverty rates among the screening tools. Our study was also limited by the types of
elderly could contribute to widening both the health and patients that we recruited; the endocrine and cardiology
wealth gap in some of Brazil’s most vulnerable citizens. outpatient clinics were the only specialties that could pro-
The only significant association found in our study vide the volume of eligible patients required for this
between adherence and patient variables was in income study’s sample size. In addition to limiting the age range
level. We believe that high adherence in the high household and types of conditions, our study was also limited in
income cohort suggests a possible relationship between terms of geographical extension. The results presented
medication adherence and socioeconomic factors for elderly here are representative of São Paulo only, and, therefore,
retirees on polypharmacy regimens. However, this is differ- may not be an accurate representation of the general
ent from other Brazilian publications as this study was Brazilian situation. However, São Paulo is the largest
carried out in the biggest city on the continent and with city in South America and has some of the highest stan-
retired government workers and their families.7,11,29 The dards of living and healthcare coverage in Latin America.
current study found low medication adherence in elderly Thus, if adherence was low in São Paulo, areas far from
outpatients across most of the analyzed socioeconomic major urban centers—where living conditions and health-
categories, except in the high household income category. care coverage are worse—may see even lower adherence
We posit that this is because the Brazilian public healthcare rates. Therefore, while our findings of specific proportions
system provides a limited amount of free medications to all of adherence may not be valid for direct comparison with
residents, but senior citizens with above-average household other cities/states in Brazil, our study exposes a clear need
income have more financial resources to purchase higher- and is a call for more research and interventions on med-
cost drugs that are sold at private pharmacies. This group ication adherence in this country.
has the necessary financial resources to procure these med-
icines as well as access to other facilitators, such as the
probable family support involved in monitoring medication
Conclusion
Medication adherence was low across all groups of retired
use as part of health care.
senior citizens, except in the group of participants with
Our findings demonstrate the need to implement public
high household income: a finding that could be key to
policies in the social and health spheres to meet the needs of
understanding medication adherence in elderly Brazilians.
the elderly population. Most senior citizens are retired and
Our study only focused on elderly residents below the age
live in predominantly low socioeconomic conditions with
of 75, and future research could focus on even older
probable low medication adherence. Educational programs
geriatric patients, such as those in their 80s, 90s, or
on how medications work and the importance of taking
older. Future studies can use our findings on socioeco-
them correctly should be implemented, with effective parti-
nomic status to focus on understanding and improving
cipation of pharmacists and nurses. This study sets a pre-
adherence, on both public policy and clinical levels.
cedent for new research on adherence improvement
methods, the importance of family participation in this
process, and the complexity of the elderly using multiple Author Contributions
medications, with its risks of complications and impacts on All authors contributed to data analysis, drafting or revis-
public health. ing the article, gave final approval of the version to be
We recognize that our study presents several limita- published, and agree to be accountable for all aspects of
tions, namely in terms of external validity. The first the work.

1626 submit your manuscript | www.dovepress.com Patient Preference and Adherence 2019:13
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Dovepress Valassi et al

Disclosure 18. Engedal K, Lacks J. Towards a Brazilian dementia plan? Lessons to

be learned from Europe. Dement Neuropsychol. 2016;10(2):44–78.
The authors report no conflicts of interest in this work. doi:10.1590/S1980-5764-2016DN1002002
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