Aim: Insulin resistance is associated with increased sympathetic activity and elevated angiotensin II which may contribute to the excessive increase in arterial blood pressure during exercise. In this study, we hypothesized that increased insulin resistance will be significantly associated with hypertensive response to exercise (HRE) in non-diabetic hypertensive patients.
Method: Two hundred seventy-five hypertensive patients were included in this study. HOMA-IR index using serum fasting glucose and insulin was calculated for insulin resistance. There were 79 patients with hypertensive response (age 56.1+/-9.4 years) and 196 patients without hypertensive response (age 53.9+/-8.9 years).
Results: Insulin resistance, assessed by HOMA index, was significantly higher in hypertensive response group as compared to control (HOMA=2.60+/-1.54 versus 1.76+/-0.86, P<0.001). HOMA was an independent predictor of HRE when controlled for age, sex, BMI and baseline SBP (odds ratio=2.008, P<0.001). Also, HOMA was significantly correlated with the magnitude of SBP elevation controlled for age, sex, BMI and baseline SBP as well (beta=0.293, P<0.001). In conclusion, this study shows that insulin resistance is a significant determinant of hypertensive response to exercise. Further studies to determine the prognostic significance of this finding is warranted.