Effectiveness of some antihypertensive medications as monotherapy among newly diagnosed black hypertensives attending a tertiary hospital in Nigeria

Abstract

The aetiology of hypertension and the effectiveness of drugs for the treatment are key areas of research. Most clinical reports are on Caucasians and/or Blacks residing in other parts of the world. The aim of this study was to compare the effectiveness of some antihypertensive medications as monotherapy among newly diagnosed black hypertensives attending a tertiary hospital in Nigeria. The study involved 25 treatment-naïve newly diagnosed hypertensives aged 20-60 years. They were randomly selected and allotted to five treatment groups (n=5) consisting of ramipril, amlodipine, atenolol, hydrochlorothiazide (administered at recommended therapeutic doses); and lifestyle modification groups. The treatment groups were each matched for sex and age with controls (n=5). A questionnaire was used to obtain basic data about subjects. Blood pressure, body mass index (BMI) and lipid profile were measured before and four weeks after the commencement of treatment. The mean systolic pressure (SP) of the hypertensives was reduced from 142.8 ± 19.9 to126.6 ± 12.7 mmHg (P<0.001). Their mean diastolic pressure (DP) was also significantly (P<0.001) reduced from 87.6 ± 11.3 to 78.7 ± 6.4mmHg. Ramipril and hydrochlorothiazide significantly reduced SP (P<0.03; P<0.006 respectively) and DP (P<0.02; P<0.005 respectively). Amlodipine was significantly (P<0.04) effective in reducing DP while the reductions in SP and DP by atenolol and lifestyle modification were not significant. The medications and lifestyle modifications had no significant effects on low density lipoproteins (LDL) and high density lipoproteins (HDL) even though there were tendencies to reduce the former and increase the latter. This study has shown that monotherapy with ramipril, amlodipine and hydrochlorothiazide but not atenolol is effective among the studied population at least within four weeks of commencing treatment. Addition of lipid lowering drugs could enhance reduction in lipid levels.

Keywords: Effectiveness, Antihypertensive drugs, blood pressure, Lipid profile, newly diagnosed hypertensives