Efficacy of Losartan Potassium and Benazepril in Hypertensive Patients With Insulin Resistance: Impact on Blood Pressure, Insulin Sensitivity, and Diabetes Risk

Background Hypertension and insulin resistance (IR) often coexist, significantly increasing the risk of type 2 diabetes and cardiovascular disease. IR plays a key role in metabolic syndrome, promoting endothelial dysfunction and impairing glucose metabolism. Angiotensin receptor blockers (ARBs) and angiotensin-converting enzyme inhibitors (ACEIs) are commonly prescribed for hypertension, but their differential effects on insulin sensitivity and diabetes risk remain unclear. This study compares the effects of losartan potassium (LP) (ARBs) and benazepril (ACEIs) on blood pressure control, insulin sensitivity, and metabolic parameters in hypertensive patients with IR. Methods A prospective cohort study was conducted from September 2023 to September 2024 at Khyber Teaching Hospital, Peshawar and Lahore Medical and Dental College, Lahore. A total of 364 hypertensive patients with IR were included. Based on physician-prescribed treatment, patients were categorized into two groups: Group A received benazepril (10 mg/day), and Group B received LP (50 mg/day). Primary outcomes included blood pressure control, Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) scores, fasting glucose, and lipid profiles, measured at baseline and regular follow-ups over 12 months. Patient adherence was monitored through self-reports and prescription refill checks. Missing data were handled using multiple imputations. Statistical analyses included independent t-tests, paired t-tests, repeated-measures ANOVA, and multivariate regression models, with a significance level set at p < 0.05. Results Both treatments significantly reduced blood pressure, but LP demonstrated greater efficacy, with superior reductions in systolic (26.4 mmHg vs. 24.7 mmHg) and diastolic (15.3 mmHg vs. 13.6 mmHg) readings (p < 0.05). HOMA-IR scores improved more in the losartan group (1.7 vs. 1.4; p = 0.02), along with a greater decrease in fasting glucose, suggesting a potential protective effect against diabetes development. Lipid profile improvements were comparable between groups. Adherence rates were similar, with a dropout rate of 8.2% and no major adverse events. Conclusions LP was more effective than benazepril in lowering blood pressure and improving insulin sensitivity, which may contribute to a lower diabetes risk in hypertensive patients with IR. A randomized controlled trial with longer follow-up is recommended to confirm these findings and assess long-term metabolic outcomes.