Hypertension is one of the leading global health concerns, significantly contributing to cardiovascular diseases, stroke, and kidney failure (1). Despite the availability of effective antihypertensive medications, achieving optimal blood pressure control remains a challenge due to poor adherence to prescribed regimens (2). Medication adherence is defined as the extent to which patients take medications as prescribed by their healthcare providers, including correct dosage, frequency, and duration (3). Non-adherence to antihypertensive therapy is a major factor leading to uncontrolled blood pressure, increasing the risk of complications and healthcare costs (4).

The prevalence of medication non-adherence among hypertensive patients varies across different populations and healthcare settings, ranging from 30% to 50% globally (5,6). Several factors contribute to poor adherence, including forgetfulness, complex medication regimens, financial constraints, side effects, and lack of awareness about the consequences of hypertension (7,8). Social and psychological factors, such as depression and lack of family support, have also been associated with non-adherence (9). Identifying and addressing these risk factors is crucial for improving adherence and achieving better treatment outcomes.

In India, studies have reported that a significant proportion of hypertensive patients fail to adhere to their medications, leading to suboptimal blood pressure control and increased risk of cardiovascular events (10,11). Understanding the prevalence and determinants of non-adherence can help in designing targeted interventions to improve adherence rates and enhance patient outcomes. Therefore, this study aims to assess the prevalence of medication non-adherence in hypertensive patients and explore the associated risk factors that contribute to this issue.

Study Design and Setting

This cross-sectional study was conducted at a tertiary healthcare centre over a period of six months. The study aimed to assess the prevalence of medication non-adherence among hypertensive patients and identify associated risk factors.

Study Population and Sample Size

A total of 400 hypertensive patients attending the outpatient department were included in the study. The sample size was determined using a standard formula based on the expected prevalence of medication non-adherence in hypertensive patients. Participants were selected using a systematic random sampling method.

Inclusion and Exclusion Criteria

Patients aged 18 years and above, diagnosed with hypertension for at least six months, and prescribed antihypertensive medications were included in the study. Patients with cognitive impairments, psychiatric disorders, or those unwilling to participate were excluded.

Data Collection

Data were collected using a structured questionnaire, which included sections on demographic details, medical history, medication adherence patterns, and potential risk factors. The Morisky Medication Adherence Scale-8 (MMAS-8), a validated tool, was used to assess adherence levels. Patients scoring less than 6 on the MMAS-8 were classified as non-adherent.

Study Variables

The primary outcome variable was medication adherence, categorized as high, medium, or low based on MMAS-8 scores. Independent variables included age, gender, education level, income, comorbidities, polypharmacy, forgetfulness, side effects, and financial constraints.

Statistical Analysis

Data were analyzed using SPSS software version 26. Descriptive statistics, including mean, standard deviation, and frequency distribution, were used for demographic characteristics. The chi-square test was applied to assess associations between categorical variables, while logistic regression analysis was conducted to determine significant predictors of medication non-adherence. A p-value of <0.05 was considered statistically significant.

Demographic Characteristics

A total of 400 hypertensive patients participated in the study. The mean age of the participants was 52.3 ± 10.5 years. Among them, 180 (45%) were males and 220 (55%) were females. Regarding education levels, 80 (20%) were illiterate, 120 (30%) had primary education, 140 (35%) had secondary education, and 60 (15%) had higher education. The employment distribution showed that 210 (52.5%) were employed, while 190 (47.5%) were unemployed. In terms of income level, 160 (40%) had a low-income status, 140 (35%) had a medium income, and 100 (25%) had a high-income status (Table 1).

Prevalence of Medication Non-Adherence

The study found that 194 (48.5%) of the patients exhibited low adherence to their antihypertensive medication, while 86 (21.5%) had medium adherence, and only 120 (30%) demonstrated high adherence (Table 2).

Factors Associated with Medication Non-Adherence

Analysis of risk factors for medication non-adherence revealed that forgetfulness (80 patients, p=0.04), polypharmacy (62 patients, p=0.01), side effects (50 patients, p=0.03), financial constraints (70 patients, p=0.01), and lack of awareness (55 patients, p=0.02) were significantly associated with poor adherence (Table 3). Patients with multiple medications and those with financial difficulties showed the highest rates of non-adherence.

These findings highlight the importance of addressing modifiable factors such as patient education, financial support, and medication reminders to improve adherence rates. ​​

Table 1: Demographic Characteristics of Participants

Table 2: Prevalence of Medication Non-Adherence

Table 3: Factors Associated with Medication Non-Adherence

Medication non-adherence remains a significant challenge in the management of hypertension, leading to poor blood pressure control and an increased risk of cardiovascular complications (1). This study found that nearly half of the participants (48.5%) had low adherence to antihypertensive therapy, which is consistent with previous studies reporting non-adherence rates ranging from 30% to 50% worldwide (2,3). Non-adherence to antihypertensive medication has been linked to various socio-economic and behavioral factors, including forgetfulness, polypharmacy, financial constraints, and lack of awareness, all of which were significantly associated with poor adherence in this study (4).

One of the major contributors to non-adherence was forgetfulness, which affected 41.2% of non-adherent patients. This aligns with findings from other studies where forgetfulness has been identified as a common reason for missing medication doses (5,6). Digital reminders, mobile health interventions, and caregiver involvement have been suggested as effective strategies to overcome this issue (7).

Polypharmacy was another significant factor influencing adherence, with 32% of non-adherent patients reporting difficulties in managing multiple medications. Patients taking multiple drugs often experience higher pill burden and confusion, leading to reduced adherence (8). Simplifying treatment regimens, using fixed-dose combinations, and educating patients about the importance of each medication may help improve adherence (9).

Financial constraints were reported by 36% of non-adherent patients, highlighting the economic burden of chronic disease management. Studies have shown that out-of-pocket expenses significantly impact medication adherence, especially in low- and middle-income countries (10,11). Policies promoting affordable healthcare, subsidized medications, and insurance coverage can reduce financial barriers and enhance adherence rates (12).

Lack of awareness about hypertension and its complications was found in 28.3% of non-adherent patients. This finding is consistent with previous studies emphasizing that patients who do not understand the severity of their condition are more likely to skip medications (13). Health education campaigns and counselling sessions by healthcare providers can help bridge this knowledge gap and motivate patients to adhere to their treatment regimen (14).

Comparing these findings with previous research, similar trends have been observed in multiple studies across different populations. A systematic review highlighted that non-adherence to antihypertensive medications is often due to a combination of behavioral, economic, and healthcare-related factors (15).

Addressing these barriers through personalized interventions, improved patient-provider communication, and policy-level changes is crucial for achieving better adherence and optimal blood pressure control.

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