Antihypertensive Drug Therapy in Patients of African and South Asian Ethnicity: A Systematic Review

Patients of South Asian or African ethnicity have a greater burden of hypertension and diabetes, leading to early target organ damage and premature cardiovascular mortality. This could have important implications for cardiovascular risk management. In this chapter, we systematically review the evidence on the effect of antihypertensive drug treatment on blood pressure, morbidity, and mortality in African and South Asian ethnicity patients. We used the Cochrane systematic review methodology to retrieve trials in electronic databases including Cochrane CENTRAL, PubMed, and Embase from their inception through September 2017. We retrieved 5311 reports that yielded 35 trials with 7 classes of antihypertensive drugs in 25,540 African ethnicity patients. Aside from the well-known blood pressure efficacy of calcium channel blockers and diuretics, with lesser effect of ACE inhibitors and beta-blockers, trials with morbidity and mortality outcomes indicated that lisinopril- and losartan-based therapy were associated with greater incidence of stroke and sudden death in African ancestry patients. In South Asian patients, 2188 reports yielded 17 randomized controlled trials with blood pressure outcomes in 1819 hypertensives. In contrast with the studies in African ethnicity patients, there were no significant differences in blood pressure lowering efficacy between drugs. We retrieved no trials with mortality outcomes in South Asians. The existing evidence indicates that ethnic-specific hypertension management may reduce cardiovascular mortality, but there is an urgent need for evidence-based strategies to reduce hypertension-related cardiovascular mortality in South Asians.