PRESCRIPTION PATTERN OF ANTI-HYPERTENSIVE DRUGS IN A TERTIARY HEALTH INSTITUTION IN NIGERIA

Objective: This study examined the pattern of physicians’ prescription of antihypertensive drugs and its possible effects on blood pressure control as well as physicians’ compliance with recommended guidelines. Methods: Records of 145 patients aged 17-91 (mean: 52.6 ± 14.6) years, with male to female ratio of 1:1.2 were randomly selected. Information on antihypertensive prescriptions was recorded. Blood pressure control was defined as systolic and diastolic blood pressure less than 140 mm Hg and 90mmHg, respectively. Results: Of the 145 patients studied, 20% (29) were on monotherapy and 80% (116) on combination therapy. Of the patients on combination therapy, 61.2% (71), 33.6% (39) and 5.2% (6) were on 2, 3 and 4 drugs, respectively. Diuretic was the most frequently prescribed drug either as a single agent (44.8%) or as combination therapy (88.8%). Mean reductions in both systolic and diastolic blood pressures were more in patients on calcium channel blocker than those on diuretic monotherapy (t = 2.5 and 3.6 for reductions in systolic and diastolic BP, respectively; P .05 for both), and, in patients on combination therapy than those on monotherapy (t = 3.64 and 3.27 for reductions in systolic and diastolic BP, respectively; P .01 for both). Blood pressure control rate was 30.5%. Conclusion: Our results are consistent with the previously observed benefits of antihypertensive combination therapy, and demonstrate an apparent higher efficacy of calcium channel blocker monotherapy than diuretic monotherapy in blood pressure lowering in the study population. Major limitations of this work include its retrospective nature and the inability to determine the actual patients’ adherence to therapy.