INTRODUCTION

Hypertension is one of the most prevalent chronic non-communicable diseases and remains a leading modifiable risk factor for cardiovascular disease, stroke, chronic kidney disease, heart failure, and premature mortality worldwide [1]. Despite the availability of effective antihypertensive therapies, blood pressure control remains suboptimal in many countries because of inadequate adherence to prescribed treatment regimens. According to the World Health Organization (WHO), approximately 1.28 billion adults aged 30–79 years are living with hypertension, with nearly half unaware of their condition, making hypertension a major global public health challenge [2].

Essential hypertension, also known as primary hypertension, accounts for approximately 90–95% of all hypertension cases and develops through a complex interaction of genetic, behavioral, and environmental factors [3]. Common modifiable risk factors include excessive dietary sodium intake, obesity, physical inactivity, tobacco use, excessive alcohol consumption, and psychological stress. The burden of hypertension is increasing rapidly in low- and middle-income countries, where healthcare resources are often limited and disease management remains challenging [2,4].

The primary goal of hypertension management is to achieve and maintain optimal blood pressure levels in order to reduce the risk of cardiovascular and renal complications. Successful management requires lifelong adherence to a comprehensive therapeutic regimen that includes pharmacological treatment, dietary modification, regular physical activity, smoking cessation, weight management, stress reduction, and routine clinical follow-up [5]. International hypertension guidelines consistently emphasize that lifestyle modification should accompany antihypertensive medication to maximize treatment effectiveness and reduce long-term cardiovascular risk [6].

Therapeutic regimen compliance, commonly referred to as treatment adherence, describes the extent to which a patient's behavior corresponds with recommendations agreed upon with healthcare professionals regarding medication use, diet, physical activity, and follow-up appointments [7]. Poor compliance is recognized as one of the principal causes of uncontrolled hypertension and contributes substantially to preventable hospitalizations, disease progression, increased healthcare expenditures, and reduced quality of life [8]. Studies indicate that nearly half of patients with chronic diseases fail to maintain long-term adherence to prescribed therapies, highlighting the importance of identifying barriers to compliance and implementing effective interventions [2,7].

Several socio-demographic, clinical, and healthcare-related factors influence therapeutic compliance among patients with hypertension. Educational attainment, economic status, health literacy, complexity of medication regimens, social support, accessibility of healthcare services, and regular physician follow-up have all been associated with adherence behaviors [8–10]. Understanding these determinants is essential for developing patient-centered interventions that improve treatment outcomes and support sustained blood pressure control.

In Iraq, hypertension represents an increasingly important public health concern, with studies reporting a high prevalence among adults and suboptimal blood pressure control despite the widespread availability of antihypertensive medications [11]. Regional evidence also suggests that limited health literacy, inadequate patient education, and inconsistent follow-up contribute to poor therapeutic adherence among hypertensive patients [11,12]. However, data regarding compliance with the complete therapeutic regimen—including medication adherence, dietary sodium restriction, and attendance at follow-up appointments—remain limited in the Kurdistan Region of Iraq.

Therefore, this study was conducted to assess the level of compliance regarding the therapeutic regimen among patients with essential hypertension attending healthcare facilities in Rania District and to determine the association between compliance and selected socio-demographic and clinical characteristics. The findings may assist healthcare providers and policymakers in designing evidence-based educational and behavioral interventions to improve adherence and optimize hypertension management.

MATERIALS AND METHODS

Study Design

A descriptive cross-sectional study was conducted to assess the level of compliance with the therapeutic regimen among patients diagnosed with essential hypertension and to examine factors associated with treatment compliance.

Study Setting

The study was carried out at Kewarash Primary Healthcare Center and Chwarqurna General Hospital in Rania District, Sulaymaniyah Governorate, Kurdistan Region, Iraq. These healthcare facilities provide comprehensive outpatient services for the diagnosis, treatment, and follow-up of patients with hypertension.

Study Population and Sampling

The study included 300 adult patients with a confirmed diagnosis of essential hypertension who attended the selected healthcare facilities between October 30, 2024, and January 28, 2025. Participants were recruited using a purposive sampling technique.

Inclusion Criteria

Patients were eligible if they:

• Were aged 40 years or older.
• Had a confirmed diagnosis of essential hypertension.
• Had been receiving antihypertensive treatment for at least six months.
• Were able to communicate effectively and complete the interview.
• Agreed to participate voluntarily and provided informed consent.

Exclusion Criteria

Patients were excluded if they:

• Had secondary hypertension.
• Were critically ill or cognitively impaired.
• Were unable to complete the interview.
• Declined to participate in the study.

Data Collection Instrument

Data were collected through face-to-face interviews using a structured questionnaire consisting of three sections:

Part I: Socio-demographic characteristics, including age, sex, marital status, residence, educational level, occupation, and monthly income.

Part II: Clinical characteristics, including duration of hypertension, family history, smoking status, alcohol consumption, physical activity, treatment regimen, clinic follow-up frequency, and blood pressure measurements.

Part III: The Hill-Bone Compliance to High Blood Pressure Therapy Scale, a validated instrument designed to assess adherence to hypertension management. The scale consists of 14 items distributed across three domains:

• Medication-taking behavior (9 items)
• Sodium intake reduction (3 items)
• Appointment keeping/follow-up (2 items)

Each item is scored using a four-point Likert scale ranging from 1 (none of the time) to 4 (all of the time). Total scores range from 14 to 56, with lower scores indicating better compliance. Compliance was categorized as:

• Good compliance: 14–28
• Moderate compliance: 29–42
• Poor compliance: 43–56

Validity and Reliability

The questionnaire was reviewed by a panel of experts in nursing and hypertension management to establish content validity. A pilot study was subsequently conducted to evaluate the instrument's reliability and clarity. The Hill-Bone Scale demonstrated acceptable internal consistency, with a reliability coefficient of r = 0.77, indicating satisfactory reliability for the present study.

Data Collection Procedure

Eligible participants were approached during their routine clinic visits. After explaining the objectives of the study and obtaining written informed consent, trained researchers conducted individual interviews in a private setting. Blood pressure measurements and relevant clinical information were obtained from patient records and confirmed during the interview when necessary. Each interview required approximately 15–20 minutes to complete.

Ethical Considerations

Ethical approval was obtained from the Scientific and Ethical Committee of the College of Nursing, University of Raparin, before commencing the study. Official permission was also obtained from the Directorate of Health and the administrations of the participating healthcare facilities. Participation was voluntary, and written informed consent was obtained from all participants before data collection. Participants were assured that their responses would remain anonymous and confidential and would be used solely for research purposes. They were informed of their right to withdraw from the study at any stage without any consequences.

Statistical Analysis

Data were entered, coded, and analyzed using the Statistical Package for the Social Sciences (SPSS), version 27.0 (IBM Corp., Armonk, NY, USA). Descriptive statistics, including frequencies, percentages, means, and standard deviations, were used to summarize participants' characteristics and compliance levels. Associations between categorical variables were examined using the Chi-square test. Statistical significance was established at p < 0.05.

RESULTS

A total of 300 patients with essential hypertension participated in this study. The participants had a mean age of 61.7 ± 10.5 years (range: 40–88 years). Slightly more than half were male (52%), the majority were married (81%), resided in suburban areas (52.7%), were illiterate (55%), and were housewives (41%). Nearly half of the participants (46%) reported insufficient monthly income (Table 1).

Regarding clinical characteristics, one-third of the participants (33.7%) had been diagnosed with hypertension for 1–5 years, while 78% reported a positive family history of hypertension. Most participants were non-smokers (86.7%) and did not consume alcohol (95%). Physical inactivity was common, with 72% reporting no regular exercise. Nearly all participants (93.3%) received pharmacological treatment alone, and 34.7% attended monthly clinic follow-up visits (Table 2).

Assessment of therapeutic regimen compliance demonstrated that 69% of participants exhibited good overall compliance, whereas 28.3% had moderate compliance and only 2.7% showed poor compliance. Good medication adherence was observed in 74% of participants, while 59.3% demonstrated good adherence to dietary sodium restriction. In contrast, most participants (89.7%) demonstrated moderate compliance with follow-up appointments (Table 3).

The association between socio-demographic characteristics and therapeutic regimen compliance is presented in Table 4. Educational level was significantly associated with compliance (χ² = 16.556, p = 0.035), with higher educational attainment corresponding to better adherence. Monthly income also demonstrated a significant association with compliance (χ² = 11.902, p = 0.018). However, no statistically significant relationships were found between compliance and participants' age (p = 0.082) or sex (p = 0.062).

Table 5 summarizes the relationship between clinical variables and compliance with the therapeutic regimen. Both systolic and diastolic blood pressure levels were highly associated with therapeutic compliance (p < 0.001). Participants with better adherence were more likely to have lower blood pressure measurements than those with moderate or poor compliance. Furthermore, the frequency of clinic follow-up visits showed a statistically significant association with treatment compliance (χ² = 20.170, p = 0.003), indicating that patients attending regular follow-up appointments demonstrated higher levels of adherence.

The distribution of antihypertensive medications used by the participants is illustrated in Figure 1. Angiotensin II receptor blockers (ARBs) were the most frequently prescribed medications (50%), followed by calcium channel blockers (46.3%), anti-hyperlipidemic agents (42%), antiplatelet drugs (32%), diuretics (25.3%), beta-blockers (23.3%), and angiotensin-converting enzyme inhibitors (22.7%). A small proportion of participants reported using vasodilators (1.3%), centrally acting alpha agonists (0.7%), or herbal medicines (6.7%) as part of their treatment regimen (Figure 1).

Table 1. Socio-demographic characteristics of patients with essential hypertension (N = 300)

Table 2. Clinical characteristics of the participants (N = 300)

Table 3. Compliance with the therapeutic regimen among patients (N = 300)

Table 4. Association between socio-demographic characteristics and overall therapeutic regimen compliance (N = 300)

Chi-square test; statistically significant at p < 0.05.

Table 5. Association between clinical characteristics and therapeutic regimen compliance (N = 300)

Chi-square test; statistically significant at p < 0.05.

DISCUSSION

This study assessed therapeutic regimen compliance among patients with essential hypertension attending two healthcare facilities in Rania District, Iraq. Overall, 69% of the participants demonstrated good compliance with the prescribed therapeutic regimen, while medication adherence was higher than adherence to dietary sodium restriction and follow-up appointments. Furthermore, educational level, monthly income, clinic follow-up, and blood pressure measurements were significantly associated with therapeutic compliance.

The findings showed that approximately two-thirds of the participants exhibited good overall compliance with their therapeutic regimen. This finding is consistent with previous studies conducted in Iraq and other countries, which reported that between 54% and 75% of hypertensive patients adequately adhered to their prescribed treatment plans [1–3]. Although the proportion of patients with good adherence in the present study is encouraging, nearly one-third of participants still demonstrated moderate or poor compliance, indicating that therapeutic adherence remains an important challenge requiring continuous patient education and follow-up.

Medication adherence represented the highest level of compliance among the three assessed domains, with nearly three-quarters of participants reporting good adherence. Similar findings have been reported in Ethiopia, Jordan, and Lebanon, where medication adherence ranged from 64% to 85% among patients receiving antihypertensive therapy [2,4,5]. The relatively favorable medication adherence observed in the current study may reflect the accessibility of antihypertensive medications through public healthcare facilities and patients' awareness of the importance of pharmacological treatment in controlling blood pressure. Nevertheless, adherence to medication alone is insufficient to achieve optimal hypertension control without appropriate lifestyle modification.

Compliance with sodium restriction was considerably lower than medication adherence, with only 59.3% of participants demonstrating good dietary compliance. This finding agrees with previous research showing that lifestyle modifications, particularly dietary sodium reduction, remain more difficult to maintain than medication use [6,7]. Dietary adherence is influenced by long-standing eating habits, cultural food preferences, family dietary practices, and limited nutritional counseling. These findings highlight the importance of integrating individualized dietary education into routine hypertension management.

Attendance at scheduled follow-up appointments demonstrated the lowest level of good compliance, with most participants classified as having moderate compliance. Regular follow-up is an essential component of chronic disease management because it facilitates blood pressure monitoring, medication adjustment, reinforcement of lifestyle modifications, and early identification of treatment-related problems. Similar findings have been reported by previous studies, which showed that irregular follow-up appointments contribute to poor blood pressure control and reduced treatment adherence [3,8].

Educational attainment was significantly associated with therapeutic regimen compliance. Participants with higher educational levels were more likely to demonstrate good adherence than those with limited education. Similar associations have been reported in studies conducted in Jordan, Egypt, and other developing countries [2,9,10]. Better educational attainment may improve health literacy, disease awareness, understanding of medical instructions, and confidence in self-management, thereby enhancing adherence to prescribed therapeutic recommendations.

Monthly income also showed a significant association with compliance. Patients with better economic status demonstrated higher levels of adherence than those with insufficient income. Financial limitations may reduce patients' ability to purchase medications, maintain healthy dietary practices, afford transportation to healthcare facilities, and attend regular follow-up visits. Comparable findings have been reported by Mohammed et al. and Abd El Hafeez, who identified socioeconomic status as an important determinant of treatment adherence among hypertensive patients [9,10].

One of the most important findings of the present study was the highly significant association between therapeutic regimen compliance and both systolic and diastolic blood pressure levels. Patients who demonstrated better compliance were more likely to achieve lower blood pressure values than those with poor adherence. This finding supports substantial evidence that adherence to antihypertensive treatment improves blood pressure control and reduces the risk of cardiovascular complications [5,11]. It also emphasizes that improving adherence should remain a major objective of hypertension management programs.

Regular clinic attendance was another significant predictor of therapeutic compliance. Participants who attended scheduled follow-up visits more frequently demonstrated higher adherence levels than those who attended irregularly or not at all. Routine follow-up provides opportunities for continuous patient education, assessment of medication-related problems, reinforcement of healthy behaviors, and early intervention when blood pressure becomes uncontrolled. Similar observations have been reported in previous studies evaluating hypertension management programs [3,8].

The present study has several strengths. It included a relatively large sample of patients from two healthcare facilities and employed the internationally recognized Hill-Bone Compliance to High Blood Pressure Therapy Scale to comprehensively evaluate medication adherence, dietary practices, and follow-up behavior. However, several limitations should be acknowledged. The cross-sectional design precludes establishing causal relationships, the use of purposive sampling may limit generalizability, and compliance was assessed through self-reported responses, which may be influenced by recall and social desirability bias. In addition, the study was conducted in one district, limiting the applicability of the findings to other regions of Iraq.

Overall, the findings emphasize that improving patient education, strengthening lifestyle counseling, encouraging regular clinic attendance, and addressing socioeconomic barriers are essential strategies for enhancing therapeutic regimen compliance and achieving better blood pressure control among patients with essential hypertension.

Limitations of the Study

This study has several limitations that should be considered when interpreting the findings. First, the cross-sectional design limits the ability to establish causal relationships between therapeutic regimen compliance and the associated socio-demographic and clinical factors. Second, participants were recruited using a purposive sampling technique from only two healthcare facilities in Rania District, which may limit the generalizability of the findings to other regions of Iraq. Third, treatment compliance was assessed using a self-reported questionnaire, making the results susceptible to recall bias and social desirability bias, which may have led some participants to overestimate their adherence. Finally, the study evaluated compliance at a single point in time and did not assess longitudinal changes in adherence or the long-term effectiveness of therapeutic regimen compliance on blood pressure control.

Conclusion

The present study demonstrated that most patients with essential hypertension exhibited good compliance with their therapeutic regimen, particularly regarding medication adherence. However, adherence to lifestyle modifications, especially dietary sodium restriction and regular follow-up visits, remains suboptimal. Educational level, monthly income, and regular clinic attendance were significant determinants of therapeutic compliance, while better adherence was strongly associated with improved blood pressure control. These findings highlight the importance of strengthening patient education, promoting continuous follow-up, and addressing socioeconomic barriers to improve long-term adherence and optimize hypertension management outcomes.