Hypertension remains one of the leading modifiable risk factors for cardiovascular disease, stroke, chronic kidney disease, and premature mortality worldwide. Despite the availability of effective antihypertensive medications, blood pressure control rates remain suboptimal, particularly in low- and middle-income countries, where the burden of hypertension is rapidly increasing.[1,2] According to recent estimates, more than one billion adults globally live with hypertension, with India contributing substantially to this burden.[3] In India, hypertension affects nearly one-third of the adult population and is responsible for a significant proportion of cardiovascular morbidity and mortality.[4,5] Although awareness, diagnosis, and treatment of hypertension have improved over the past decade, achieving sustained blood pressure control remains a major challenge.[6] One of the most important determinants of poor blood pressure control is inadequate adherence to prescribed antihypertensive therapy.[7] Medication adherence refers to the extent to which a patient's medication-taking behavior corresponds with agreed recommendations from a healthcare provider.[8] Suboptimal adherence has been associated with uncontrolled hypertension, increased risk of cardiovascular events, frequent hospitalizations, reduced quality of life, and higher healthcare expenditures.[9,10] Factors influencing adherence are multifactorial and include patient-related, therapy-related, socioeconomic, and health-system-related determinants.[11] Evidence from different regions of India suggests considerable variability in adherence levels owing to cultural, socioeconomic, and healthcare-access disparities.[12,13] However, data from eastern India, particularly West Bengal, remain limited. Understanding the burden of suboptimal adherence in this setting is essential for designing targeted interventions to improve treatment outcomes and reduce cardiovascular risk. Therefore, the present study aimed to estimate the burden of suboptimal adherence to antihypertensive therapy among patients attending a tertiary care centre in West Bengal, India and factors associated with their adherence.

MATERIALS AND METHODS

Study design: A hospital-based cross-sectional analytical study.

Study Place: Prafulla Chandra Sen Government Medical College and Hospital (PCSGMCH), Arambagh, West Bengal.

Study Population: The study population comprised adult hypertensive patients aged 18 years or older who had a physician-confirmed diagnosis of hypertension for at least two years and were receiving antihypertensive medication at the time of the survey.

Duration of the Study: 2 Years

Sample Size: 112 patients

Inclusion Criteria:

• Adult patients aged 18 years and above.
• Diagnosed cases of hypertension for at least 2 years by a registered medical practitioner.
• Currently receiving antihypertensive medication.
• Attending the outpatient department of the study hospital during the study period.
• Willing to participate and provide written informed consent.

Exclusion Criteria:

• Patients with severe illness or medical emergencies requiring immediate treatment.
• Patients with cognitive impairment, psychiatric illness, or communication difficulties that prevent reliable interview.
• Pregnant women with gestational hypertension/preeclampsia.
• Patients unwilling to participate or provide informed consent.
• Incomplete or unreliable responses to the study questionnaire.

Study Variable:

• Antihypertensive medication adherence status (HB-MAS score)
• Blood pressure control status (Controlled/Uncontrolled)
• Duration of hypertension
• Socio-economic status
• Out-of-pocket expenditure for treatment
• Occupation
• Comorbidities
• Medication consumption per day (pill burden)
• Clinical status of hypertension
• Healthcare-seeking behaviour

Statistical Analysis: For statistical analysis data were entered into a Microsoft Excel spreadsheet and then analyzed by SPSS (version 27.0; SPSS Inc., Chicago, IL, USA) and Graph Pad Prism version 5. Data had been summarized as mean and standard deviation for numerical variables and count and percentages for categorical variables. Z-test (Standard Normal Deviate) was used to test the significant difference of proportions. Once a t value is determined, a p-value can be found using a table of values from Student's t-distribution. If the calculated p-value is below the threshold chosen for statistical significance (usually the 0.10, the 0.05, or 0.01 level), then the null hypothesis is rejected in favor of the alternative hypothesis. P-value ≤ 0.05 was considered for statistically significant.

RESULT

Table 1: Distribution of Socio-demographic and Clinical profile of the study participants (N=112)

Table 2: Bivariate analysis showing the association between Socio-demographic and Clinical profile of the study participants and adherence score to antihypertensives (N=112) Top of Form

Table 3: Distribution of Hill-Bone Medication Adherence Scores Among Study Participants (N=112)

Table 4: Domain-wise Hill-Bone Medication Adherence Scale Scores (N=112)

Table 5: Association Between Adherence Category and Blood Pressure Control

Figure 1: Distribution of Socio-demographic and Clinical profile of the study participants (N=112)

Figure 2: Comparison of Communication Skill Improvement by Gender

Distribution of Socio-demographic and Clinical Profile of the Study Participants

RESULTS

The study included 112 hypertensive patients. The majority belonged to the age groups of 41–59 years (41.07%) and ≥60 years (41.97%). Males constituted 53.57% of the participants. Most participants were currently married (66.96%), while 38.39% were illiterate. Homemakers represented the largest occupational group (32.14%), and 36.61% belonged to socio-economic class V. The majority had hypertension for less than 10 years (72.32%) and sought care exclusively from public health facilities (59.82%). Comorbidities were present in 65.18% of participants, while 41.96% reported out-of-pocket expenditure for treatment.

Interpretation

The study population primarily consisted of middle-aged and elderly hypertensive patients with a slight male predominance. Most participants had a relatively shorter duration of hypertension and relied on public healthcare services. A substantial proportion belonged to lower socio-economic classes and had associated comorbidities, indicating a potentially vulnerable patient population requiring sustained long-term care and support.

Bivariate Analysis Showing Association Between Participant Characteristics and Adherence Score

Results

Significant associations with adherence score were observed for occupation (p=0.030), socio-economic status (p=0.031), duration of hypertension (p<0.001), and out-of-pocket expenditure (p=0.001). Homemakers had the highest mean adherence score (27.25±6.00). Participants with hypertension duration of less than 10 years demonstrated significantly higher adherence scores (26.27±5.30) than those with hypertension for 10 years or more (20.39±7.25). Individuals without out-of-pocket expenditure also showed better adherence (26.26±5.88) compared to those incurring treatment expenses (22.40±6.55). No significant association was observed with age, gender, marital status, education, clinical status, care-seeking behaviour, comorbidities, smoking status, knowledge about complications, side effects, hypertension-related complications, or number of medications consumed per day (p>0.05).

Interpretation

The findings suggest that treatment-related and socio-economic factors play an important role in medication adherence. Longer disease duration and financial burden adversely affected adherence, whereas favourable socio-economic conditions and homemaker status were associated with better adherence. These results highlight the importance of addressing economic barriers and providing continued support for patients with longstanding hypertension.

Distribution of Hill-Bone Medication Adherence Scores Among Study Participants

Results

Among the study participants, 42 (37.50%) demonstrated good adherence to antihypertensive therapy, while 38 (33.93%) showed moderate adherence and 32 (28.57%) exhibited poor adherence. Overall, 70 participants (62.50%) were classified as having suboptimal adherence.

Interpretation

The burden of suboptimal adherence was high, affecting nearly two-thirds of the hypertensive patients. This finding indicates that inadequate adherence to antihypertensive therapy remains a major challenge and may contribute to poor long-term disease control and increased risk of complications.

Domain-wise Hill-Bone Medication Adherence Scale Scores

Results

The mean overall Hill-Bone Medication Adherence Scale score was 24.64±6.43. Among the individual domains, medication-taking behaviour had the highest mean score (13.82±3.44), followed by appointment keeping (6.27±1.83) and salt intake behaviour (4.52±1.41).

Interpretation

Medication-taking behaviour contributed most substantially to the overall adherence score, indicating that difficulties in maintaining regular medication use were a major component of adherence-related challenges. The findings suggest that interventions targeting medication-taking practices may yield the greatest improvement in overall adherence.

Association Between Adherence Category and Blood Pressure Control

Results

Among participants with good adherence, 34 (80.95%) had controlled blood pressure, whereas 8 (19.05%) had uncontrolled blood pressure. Among those with suboptimal adherence, 55 (78.57%) had controlled blood pressure and 15 (21.43%) had uncontrolled blood pressure. The association between adherence category and blood pressure control was not statistically significant (p=0.759).

Interpretation

Although a higher proportion of participants with good adherence had controlled blood pressure, the difference was not statistically significant. This suggests that factors other than medication adherence, such as treatment regimen, disease severity, lifestyle factors, and comorbid conditions, may also influence blood pressure control in this population.

DISCUSSION

The present hospital-based cross-sectional analytical study evaluated the burden of suboptimal adherence to antihypertensive therapy among 112 adult hypertensive patients attending a tertiary care centre in West Bengal. The findings demonstrate that medication adherence remains a major challenge in hypertension management, with important associations observed between adherence behaviour, socio-economic factors, treatment burden, and duration of disease. In the present study, the majority of participants were middle-aged and elderly, with 41.07% belonging to the 41–59 years age group and 41.97% aged ≥60 years. Similar demographic patterns have been reported in hypertension studies where older adults constitute a major proportion due to increased risk of vascular changes and chronic disease burden with advancing age [14]. A slight male predominance (53.57%) was observed in the present study, which is comparable with findings from several Indian studies showing higher healthcare utilization among male hypertensive patients, although adherence patterns may vary depending on social support and healthcare accessibility [15]. The study showed that comorbidities were present among 65.18% of participants. Hypertension commonly coexists with diabetes, cardiovascular disease, and other chronic conditions, increasing medication burden and complexity of treatment. Previous studies have demonstrated that multimorbidity and polypharmacy are important contributors to poor adherence due to increased regimen complexity and reduced patient motivation for long-term therapy [16]. A major finding of the present study was the high burden of suboptimal adherence, with 62.50% of participants classified as having moderate or poor adherence. This indicates that nearly two-thirds of hypertensive patients had difficulty maintaining optimal medication-taking behaviour. Similar observations have been reported in previous studies, where non-adherence rates among hypertensive patients ranged widely due to differences in population characteristics and assessment methods [17]. Poor adherence is a significant public health concern as it contributes to inadequate blood pressure control, increased cardiovascular events, and higher healthcare expenditure [18]. The mean overall Hill-Bone Medication Adherence Scale score in the present study was 24.64±6.43. Among the different domains, medication-taking behaviour showed the highest mean score (13.82±3.44), suggesting that regular medication intake and maintaining daily treatment schedules represent major challenges. The Hill-Bone scale has been widely used to assess adherence-related behaviours, and previous research has emphasized the importance of identifying specific behavioural barriers rather than focusing only on clinical outcomes. In the present analysis, occupation showed a significant association with adherence score (p=0.030). Homemakers demonstrated better adherence compared with other occupational groups. This may be due to greater availability of time, regular daily routines, and better opportunity to incorporate medication schedules into daily activities. Similar studies have reported that lifestyle patterns, work-related stress, and daily responsibilities influence medication-taking behaviour among patients with chronic diseases [19]. Socio-economic status was significantly associated with adherence (p=0.031). Participants from lower socio-economic backgrounds showed comparatively lower adherence scores, which may be related to financial limitations, difficulty accessing medicines, and competing household expenses. The present study also found a significant association between out-of-pocket expenditure and adherence (p=0.001), with patients without additional treatment-related expenses showing better adherence. Financial barriers have been consistently identified as important determinants of poor adherence, especially in low- and middle-income countries. Duration of hypertension showed a strong association with adherence (p<0.001). Patients with hypertension duration of less than 10 years had significantly higher adherence scores compared with those having hypertension for ≥10 years. Longer disease duration may lead to treatment fatigue, reduced perceived benefit of medication, and decreased motivation for lifelong therapy. Similar findings have been reported where chronic disease duration was associated with declining medication adherence over time. Although good adherence was associated with a higher proportion of controlled blood pressure (80.95%) compared with suboptimal adherence (78.57%), the difference was not statistically significant (p=0.759). This suggests that blood pressure control is influenced by multiple factors, including lifestyle modifications, dietary practices, physical activity, drug regimen, disease severity, and biological response to therapy. Previous studies have also highlighted that adherence alone may not completely explain variations in blood pressure control [20]. Overall, the findings emphasize that suboptimal adherence is a major challenge among hypertensive patients in Eastern India. Interventions focusing on patient education, reduction of financial barriers, simplified treatment regimens, regular follow-up, and behavioural counselling may improve adherence and contribute to better hypertension outcomes.

CONCLUSION

The present study concludes that suboptimal adherence to antihypertensive therapy is highly prevalent among patients attending a tertiary care centre in West Bengal, with nearly two-thirds of participants demonstrating moderate to poor adherence. Adherence was significantly influenced by occupation, socio-economic status, duration of hypertension, and out-of-pocket expenditure, highlighting the role of socio-economic and treatment-related barriers in long-term disease management. Although better adherence was associated with a higher proportion of controlled blood pressure, the relationship was not statistically significant, indicating the influence of multiple factors on hypertension control. Strengthening patient counselling, improving medication accessibility, reducing financial barriers, and implementing regular follow-up strategies are essential to improve adherence and reduce the burden of hypertension-related complications.

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