Compliance to hypertensive prescribing guidelines and blood pressure control in elderly patients in Namibia: findings and implications

Objective: Resources-limited countries in sub-Saharan Africa are facing a crisis of hypertensive-related morbidity, mainly due to poor blood pressure (BP) control. The study aimed to evaluate BP control and hypertensive prescribing for elderly patients in a resource-limited setting. Methods: Hospital-based survey assessing hypertensive prescribing practices among elderly patients (age, ≥60years) at a leading ambulatory care clinic in Namibia. The primary and secondary outcomes were compliance with prescribing guidelines, prescribing patterns and BP control respectively. Data were collected using patient exit interviews and a review of their prescription records. Data were analyzed using descriptive statistics using SPSS v25. Key findings: Of the 189 elderly patients recruited, 69.3% were females, mean age was 70.3±8.5 years and 2.6% had HIV. 61.4% of the prescriptions complied with the prescribing guidelines in terms of treatment choice and 78.3% (n=148) had a poor BP control. 61.4% had at least one comorbidity, mainly diabetes mellitus (32.2%) or cardiac disease (20%). On average, 4.5 medicines were prescribed per patient and 4.8% were out of stock. Prevalence of non-INN prescribing was 64%. Diuretics, renin-angiotensin inhibitors were the most prescribed antihypertensive, 73.9% (n=138/189) and 51.9% (n=98/189) respectively. 90% of patients with good BP control were on ≥3 medicines compared to 77% for patients with poor BP controlled. Conclusion: Whilst compliance with prescribing guidelines is modest, the sub-optimal BP control, high prevalence of co-morbidities and over prescribing with non-INN products is discouraging. Pharmacist-led medication audits could improve hypertensive prescribing and BP control among elderly patients, and we will be following this up