# Citation

Hasen G, Abdo A (2020) Medication Adherence and Associated Factors in Management of Hypertension in Shashemene Referral Hospital, Ethiopia. J Hypertens Manag 6:054. doi.org/10.23937/2474-3690/1510054

# Medication Adherence and Associated Factors in Management of Hypertension in Shashemene Referral Hospital, Ethiopia

##### Gemmechu Hasen1* and Awel Abdo2

1School of Pharmacy, Institute of Health, Jimma University, Jimma, Ethiopia

2Shashemene Referral Hospital, Westi Arsi, Ethiopia

# Abstract

## Background

Despite the availability of effective treatment, over half of the patients being treated for hypertension drop out of care entirely within a year of diagnosis. Adherence to antihypertensive medication is an effective step for controlling blood pressure and preventing complications. This study is aimed to assess medication adherence and associated factors in the management of hypertension in Shashemene Referral Hospital, South Ethiopia.

## Methods

Hospital-based cross-sectional study was conducted to assess medication adherence and associated factors among 197 hypertensive patients on treatments at Shashemene Referral Hospital. A simple random sampling technique was used to select the study participants from the study population. Sociodemographic data, medication adherence, factors affecting adherence were collected using a structured questionnaire and an 8-item Morisky medication adherence scale. The collected data were processed and analyzed using SPSS version 20. Chi-square was used to determine the association between the level of medication adherence and socio-demographic characteristics of hypertensive patients at a 5% (p < 0.05) level of significance.

## Results

Among 197 respondents 123 (62.6%) were males and the mean age was 47 ± 13 years. From a total of 197 study participants, 125 (63.5%) of respondents were adherent to their prescribed medication and the rest were non-adherents. Factors such as occupation (p = 0.033), and source of medical service or treatments (p = 0.037), were associated with antihypertensive medication adherence. Moreover, there is a significant association between adherence and blood pressure control (p = 0, p < 0.05). Among study subjects with uncontrolled blood pressure, 50 (25.5%) respondents had low adherence to antihypertensive medications, and the remaining subjects 31 (15.7%), 13 (6.7%) had medium adherence, and high adherence respectively.

## Conclusions

More than half of the study participants were found to be adherent to their treatments according to the 8-item Morisky medication adherence scale. Occupational status and source of medical service or treatments were the most common factors associated with antihypertensive medication adherence. Moreover, the status of blood pressure control was significantly associated with the pattern of adherence.

# Keywords

Adherence, Hypertensive patients, BP control, Shashemene

# Abbreviations

BP: Blood pressure; CHF: Congestive heart failure; DM: Diabetes mellitus; HTN: Hypertension; HIV: Human immunodeficiency virus; JU: Jimma university; MMAS-8: Morisky's 8-item medication adherence scale; SRH: Shashemene referral hospital; TB: Tuberculosis

# Methods and Materials

## Study design, period and area

The cross-sectional study design was conducted at Shashemene referral hospital from February to March 2019 at Shashemene Referral Hospital (SRH). Shashemene is located 250 km from Addis Ababa on the way to Hawasa and it is found in west Arsi zone of Oromia regional state. SRH serves a population of eight million in Oromia and neighboring South Ethiopian communities. Hospital possesses different types of departments which include Pediatrics, Internal medicine, Gynobstristics, and Surgery. The Hospital also has also other departments like Psychiatry, Ophthalmology, Dermatology, and Neurology. The hospital has TB-HIV clinic and MDR-TB clinic separately. And others like DM, CHF, HTN currently has no clinic separately, but they patients follow at different OPD (Out Patient Department) which is separated as case 1-6 in OPD.

## Population

Source population: All hypertensive patients attending at Shashemene Referral Hospital of medical Outpatient department for treatment follow up.

Study population: All adult hypertensive patients who are greater than 18-years-old, and on follow up for at least six month and visiting the hospital during the study period fulfilling inclusion criteria at Shashemene Referral Hospital.

## Sample size and sampling technique

Sample size: The sample size for the study was determined using the following formula [11].

Where:

${n}_{i}$ - The initial sample size required

❖ p - Prevalence of adherence (64.5%) [11]

❖ d - The margin of sampling error tolerated (5%)

$Z\alpha /2$ - Percentage confidence level (1.96)

Therefore, the sample size is:

Since our source population is less than 10,000, which are 450 we use the correction formula as follows.

Where,

❖ nf = Final sample size

❖ n = Total study population which is 351

❖ N = Source of population which is 450

Sampling technique: All patients attending hypertension clinics who had fulfilled inclusion criteria were interviewed until desired sample were obtained.

## Study variable

Independent variables: Sociodemographic characteristics like age, gender, sex, occupational status, educational status, religion, ethnicity, monthly income, marital status, source of medical service or treatments and duration of treatment.

Dependent variable: Pattern of adherence towards antihypertensive medications and blood pressure control.

## Inclusion and exclusion criteria

Inclusion criteria: All adult hypertensive patients those are greater than 18-years-old, and on follow up for at least six months duration and on medication during the study period.

Exclusion criteria: All patients who are critically ill or psychiatric patients.

# Data Collection Procedure

## Instrument

Data was collected by using Morisky's 8-item Medication Adherence Scale [12,13] to assess magnitude of non-adherence, and standard questionnaire consisting closed question to address factor affecting adherence to antihypertensive medications.

## Data collection method

At each OPD rooms selected data collectors were identified participants who fulfill the criteria to be involved in the study while they exit after they got service. Using standard questionnaires and Morisky's 8-item Medication Adherence Scale data collectors were interviewed targeted hypertensive patients during their exit from the OPD after they got service. During interview other patients were separated to not hear others response to avoid bias.

## Data analysis procedure

Data was collected, and the patient responses was cleared, entered in to a computer and relevantly organized and percentage with computer and present in table and chart. Statistical significance test was applied to reflect the association between the variables by using statistical package for social science version 20 (SPSS version-20). Accordingly, chi-square was used to determine the association between the level of medication adherence and socio-demographic characteristics of hypertensive patients at a 5% (p < 0.05) level of significance.

## Data quality control

During data collection supervision was carried out and daily checking of the collected data was made by principal investigator. To assure data quality, pretest was conducted; data collectors were recruited; training and orientation were given to data collectors.

# Operational Definition

Is defined as "the extent to which a person's behavior taking medication, following a diet, and/or executing lifestyle changes corresponds with agreed recommendations from a health care provider" [6].

## Hypertension

Is defined as the persistent systolic blood pressure equal to and greater than 140 mmHg and/or persistent diastolic blood pressure equal to and greater than 90 mmHg [1].

## Hypertensive patient

Refers to a person diagnosed with hypertension as defined above.

Any form of deviation from adherence like losing one appointment, missing doses [6].

# Ethical Considerations

Jimma University Institutional Review Board approved the research. A formal letter was obtained from the Department of Pharmacy, college of Health Sciences and permission was obtained from Shashemene Referral Hospital, Oromia, and West Arsi, to collect data. The concerned hospital was also assured that the data was kept confidential. Each respondent who was interviewed was asked to give their consent after explaining the purpose, objective, and benefit of the study. Then respondents, who were volunteers, were interviewed. The participants were free to withdraw from the interview at any stage without incurring any consequences.

# Results

Among 197 respondents 123 (62.6%) were males and mean age was 47 ± 13 year. Among study respondents 44 (22.33%) were age between 45-49 years, and followed by 37 (18.78%) which belongs to age between 35-39, and average mean, and standard deviation were 47.2, 12.88 respectively. Larger proportions of respondents started their medications 1-3 years 140 (71.06%) back, and small proportion of respondents 4 (2.03%) were started > 6 years back. Among study participants 102 (51.7%) were Muslim, followed by orthodox 66 (33.5%). From study participants 155 (78.7%) of respondents were married, while 26 (13.2%) were divorced. Larger proportions of respondents 111 (56.3%) were illiterate. Among study subjects 55 (27.9%) of the respondents had 446-1200 birr of monthly income while others respondents 27 (13.7%), 6 (3.04%), 17 (6.1%) had 1201-2500, 2501-3500, and greater than 3501 respectively. But, remaining respondents 94 (47.7%) do not know their monthly income in money. Among study subjects 85 (43.14%) of respondents were farmers. Larger proportions of respondents 167 (84.8%) had no family support (Table 1).

Table 1: Socio-demographic characteristics of respondents in SRH Ethiopia, 2019. View Table 1

Figure 1: Reason for poor patient awareness on the importance of adherence to antihypertensive medications in SRH, Ethiopia, 2019. View Figure 1

Figure 2: Magnitude of adherence in study participants in SRH, Ethiopia, 2019. View Figure 2

From total of study participants, who had irregular follow up due to patients related factor, 21 (42.9%) of respondents were due to forgetfulness, and the left were lack of money 15 (30.6%) and negligence (26.5%) (Table 2).

Table 2: Patients related factors that lead to irregular follow up among study participants in SRH, Ethiopia, 2019. View Table 2

From the study participants the prolonged duration of the treatment 34 (81%) was a major treatment related factor that leads to irregular follow up. Other respondents that had not regular follow up due to treatment related factors such as adverse effect of the drug, different kind of medicine, and lack of the role health worker were 3 (7.1%), 3 (7.1%), and 1 (2.4%), respectively (Table 3).

Table 3: Treatments related factors that lead to irregular follow up among study participants in SRH, Ethiopia, 2019. View Table 3

Table 4: Effects of adherence on BP control among study population in SRH, Ethiopia, 2019. View Table 4

In this study there is significant association between occupation (p = 0.033), source of medical service or treatments (p = 0.037) (Table 5). Moreover, there is significant association between adherence and blood pressure control (p = 0, p < 0.05). Majority respondents who had low adherence belong to uncontrolled blood pressure (Table 6).

Table 5: Association between socio-demographic data and respondents with adherence status in SRH, Ethiopia, 2019. View Table 5

Table 6: Association between adherence and status of blood pressure in SRH, Ethiopia, 2019. View Table 6

# Study Limitations

This study have the following limitations: Self-reporting was used as the only method of measuring adherence. This method has the disadvantages of recall bias and eliciting only socially acceptable responses and hence, may overestimate the level of adherence. In addition, it did not consider HTN patients who did not visit the hospital during the time of the study. Hence, the extent of generalizability is limited only to those similar patients who are on chronic illness follow up care.

# Conclusions

More than half of the study participants were found to be adherent to their treatments according to 8-item morisky medication adherence scale. Occupational status and source of medical service or treatments were the most common factors associated antihypertensive medication adherence. Moreover, the status of blood pressure control was significantly associated with pattern of adherence.

Not applicable.

# Authors' Contribution

GH and AA designed, extracted, analyzed and interpreted the data. GH conceived the study; guided the design and supervised the whole research. GH also prepared the manuscript. Both authors read and approved the final manuscript.

# Citation

Hasen G, Abdo A (2020) Medication Adherence and Associated Factors in Management of Hypertension in Shashemene Referral Hospital, Ethiopia. J Hypertens Manag 6:054. doi.org/10.23937/2474-3690/1510054