Factors influencing treatment adherence in hypertension and HIV management in South Africa: A comparative literature review

BACKGROUND: Hypertension (HTN) is the most significant risk factor for cardiovascular disease (CVD) in South Africa (SA), with one in three people over the age of 25 suffering from HTN. Whilst human immunodeficiency virus and acquired immunodeficiency syndrome (HIV/AIDS) are the leading causes of death in South Africa, CVD is in the top 10 causes of death, demonstrating the importance of detecting and controlling blood pressure early on. This study aimed to review adherence factors to antihypertensive medication and antiretroviral therapy (ART) and evaluate the resulting factors influencing adherence discrepancies within the South African population. METHODS: A comprehensive literature review was carried out. PubMed, ScienceDirect, Cochrane and Embase were searched for English publications between 2000 and 2021. RESULTS: A total of 50 articles covering quantitative and qualitative studies were included. Many studies identified poor adherence levels to antihypertensive treatment, reaching a substandard adherence rate of 41.9%, whilst most studies on the HIV-positive population reported good levels of adherence, with adherence rates of more than 90%. Being of the male gender, advanced age, low socioeconomic status and a low level of education were associated with unsatisfactory adherence rates in both groups. Within the HIV group, more participants had better knowledge concerning the extent of their disease and its required treatments. CONCLUSION: The results present substandard adherence levels to antihypertensives compared with antiretroviral (ARV) adherence, despite the influence of more non-adherence factors in the HIV group. The authors recommend better adherence counselling for patients with HTN during every clinic visit, regular healthcare worker training and the implementation of ART adherence programmes in patients with hypertension.