Influence of West African Ethnicity and Gender on Beta-Cell Function and Insulin Sensitivity in Essential Hypertensives Treated with Hydrochlorothiazide and Hydrochlorothiazide-lisinopril Combination

Abstract

Objective:To assess the effects of hydrochlorothiazide (HCT) given alone and in combination with an angiotensin-converting enzyme inhibitor (ACEI) on beta-cell function in a negroid population to further explore possible ethnic differences in the effect of antihypertensive drugs on homeostasis model assessment – insulin resistance (HOMA-IR).Materials and Methods:A total of 80 newly diagnosed Nigerian essential hypertensive patients were assigned to receive either HCT 25 mg daily or both HCT and lisinopril (Lis; 25/10 mg daily) in an open-label study for 12 weeks. The treatment groups were well matched in clinical and demographic baseline features. Changes in HOMA-IR from baseline to end of study (week 12), fasting plasma glucose (FPG), serum potassium, serum insulin, and blood pressure over the same period were also evaluated.Results:After 12 weeks, mean delta HOMA-IR (and %) was higher in the HCT monotherapy group; although, this change did not reach statistical significance in both groups −0.1 ± 7.1, P = 0.538 (HCT) and 0.6 ± 4.2 P = 0.913 (HCT + Lis); an insignificant increase was observed in FPG and serum insulin in both groups, whereas serum potassium decreased in similar fashion. Blood pressure reduction was similar in both groups. Analysis of HOMA-IR change according to gender in response to HCT mono- or combination therapy with Lis showed no significant difference.Conclusions:HCT monotherapy in hypertensive indigenous Nigerians, was not associated with worse metabolic effects when compared with combination therapy using Lis, an ACEI after 12 weeks. Low-dose thiazide diuretic as first-line antihypertensive medication may be safe in the short-term, further larger and long-term studies are needed to corroborate this finding.

Pathophysiologically based antihypertensive pharmacotherapeutics rationality, efficacy and safety in Sub Saharan African Nations – A review

“…See Table 2 [ 43 , 44 , [45] , [46] , [47] , [48] , [49] , [50] , [51] , [52] , [53] , [54] , [55] , [56] , [57] ]. Low dose HCTZ alone, or combined with Lisinopril, in a single pill combination, did not impair Insulin sensitivity, beta cell function, or cause hyperglycemia, in HT patients whose blood potassium was unchanged [ 77 ]. In the therapeutic audit reports of hypertension and its treatment (See Table 2 ) in Ethiopia [ 45 ], Ivory coast [ 46 ], Kenya [ 47 ], and various parts of Nigeria, DM was the commonest co-morbidity reported.…”