Pilot comparison of clinical effects and compliance with commonly prescribed antihypertensive drugs in HIV hypertensive patients at University Teaching Hospital

Abstract

Pilot comparison of clinical effects and compliance with commonly prescribed antihypertensive drugs in HIV hypertensive patients at UTH. By Dr Takondwa Ngulube Chidumayo HIV infection and hypertension disproportionately affect sub-Saharan Africa including Zambia. The challenges of effectively treating patients with these co-morbidities include pill burden, drug interactions that may influence the efficacy and side effect profile of antihypertensive and antiretroviral therapies. This study determined the association between clinical effects regarding blood pressure control, side effect profile and compliance with the commonly used antihypertensive drugs classes in Zambia. The study was a prospective cohort analysis of randomly selected hypertensive people living with HIV (PLWHIV) on commonly used antihypertensive drug classes. Antihypertensive drug efficacy was assessed using sitting clinic and 24-hour ambulatory blood pressure monitoring (ABPM) for participants on antihypertensive drugs for at least six weeks. The validated anti-retroviral therapy (ART) clinic follow-up questionnaire and ‘WHO questionnaire for hypertension in a rapidly ageing population’ gathered quantitative data on management, treatment, patient knowledge and complications of HIV and hypertension during the 8 -week period at Adult Infectious Disease Centre (AIDC). To determine the most effective, safest antihypertensive therapies acceptable to this population. Participants on CCB (140.4/98.8 mmHg) and CCB with Enalapril (147.9/92.7 mmHg) had higher median daytime blood pressure than Moduretic (136.8/84.2 mmHg, p=0.186 and 0.168 respectively) and Moduretic with Enalapril (140.5/84 mmHg, p= 0.003). The attributable risk for good daytime systolic and diastolic BP control was at least 20 % and 32 % for Moduretic and Enalapril (50 % and 67 %, p=0.046 and 0.0143 respectively) and Moduretic (50 % and 62%, p=0.691 and 0.425 respectively). The circadian systolic and diastolic BP decrease was less than 10 % for Moduretic and Enalapril (8.25 % and 10.25 %, p=0.005 and 0.003, respectively). The difference in the median clinic systolic and diastolic BP (170/106 mmHg) was greater than 22.62 mmHg and 11.20 mm Hg than daytime ABPM (142/95.5 mmHg, p = 0.0001 and 0.001 respectively). Moduretic had the highest side effect proportion (62.5 %), mainly related to hypokalemia in patients on Tenofovir (p=0.25). The highest occurrence of non-compliance was in CCBs with Enalapril (50 %) and CCBs (40 %) with p= 0.048. CCBs with Enalapril (100 %) and Moduretic with Enalapril (100 %) had the highest proportion of awareness of the importance of compliance and BP control (p=0.02). This finding mitigated the effects of increased antihypertensive pill burden which did not affect compliance, especially in the latter group. The study supported the alternative hypothesis. Moduretic with Enalapril had the highest ration of BP, with fewer side effects and better compliance. The use of Nifedipine ® in PLWHIV on NNRTIs should be carefully monitored as combinations with and Enalapril alone is less efficacious in hypertensive PLWHIV of African origin. Antihypertensive drug compliance improved by patient knowledge of hypertension treatment rather than reduced pill burden. A more rigorous study iv long-term with larger samples sizes is required to determine the BP control rates using more diverse combinations of antihypertensive drugs, Nifedipine XR formulations, hypertension in PLWHIV.