Hypertension among HIV patients: prevalence and relationships to insulin resistance and metabolic syndrome

Objectives Metabolic syndrome is a cluster of risk factors, such as central obesity, dyslipidemia, glucose intolerance, hypertension, related to insulin resistance. In HIV patients insulin resistance and several metabolic abnormalities of the metabolic syndrome have been described, but few and conflicting studies have investigated the behaviour of blood pressure. The aims of the present study were to evaluate the prevalence of hypertension in a large group of HIV-patients on highly active antiretroviral therapy (HAART) and to investigate the relationship between hypertension, metabolic syndrome and insulin resistance. Design Case control study Methods We enrolled 287 HIV-positive patients on HAART (mean age 41.1 +/- 7.5 years) and 287 age- and sex-matched controls. Insulin resistance was estimated by the homeostasis model insulin resistance assessment (HOMA) index. Metabolic syndrome was defined according to the European Group for the Study of Insulin Resistance. Results HIV patients showed a prevalence of subjects with hypertension (34.2 versus 11.9%; P < 0.0001) and metabolic syndrome (33.1 versus 2.4%; P< 0.0001) higher than controls. HOMA was higher in HIV-patients than controls (3.3 +/- 1.2 versus 2.0 +/- 0.9; P < 0.0001). HOMA (3.7 +/- 1.0 versus 3.1 +/- 1.2; P< 0.001) and the prevalence of subjects with the metabolic syndrome (64.3 versus 16.9%; P< 0.0001) were greater in HIV-patients with than in those without hypertension. Multiple logistic regression analysis showed that family history of hypertension (odds ratio [(OR): 8.73; 95% confidence interval (CO: 4.31 -17.70; P< 0.0001], metabolic syndrome (OR: 6.79; 95% Cl: 3.27-14.10; P< 0.0001), lipodystrophy (OR: 4.80; 95% Cl: 2.43-9.85; P< 0.0001) and HOMA (OR: 4.13; 95% Cl: 1.14-14.91; P< 0.05) were predictors of hypertension in HIV-patients. Conclusions The present study shows that hypertension is frequent in HIV patients on HAART and that hypertension appears to be linked to insulin resistance; in particular, hypertension seems to be a part of the metabolic syndrome.