Differential effect of obesity on prevalence of cardiac and carotid target organ damage in hypertension (the Campania Salute Network)

Abstract

Background: Whether increasing body mass index (BMI) is independently associated with parallel increased prevalence of hypertensive vascular and cardiac target organ damage (TOD) needs further clarification.

Methods: We analyzed 8815 hypertensive patients without prevalent cardiovascular disease, participating in the Campania Salute Network, grouped into BMI classes (normal 20-24.9kg/m², overweight 25-29.9kg/m² and obese ≥30kg/m²). Vascular and cardiac TOD was defined as ultrasound plaque (intima-media thickness>1.5mm) in >1 of the common or internal carotid arteries and echocardiographic left ventricular (LV) hypertrophy (LVH) (LV mass/height^2.7>47g/m^2.7 in women and >50g/m^2.7 in men), respectively.

Results: A majority of patients were either overweight (49%) or obese (27%). In spite of more use of combination therapy, the obese group had higher blood pressure (BP) and prevalence of TOD. In multivariate logistic analyses, obesity was associated with a 6.9 times higher prevalence of LVH (95% confidence interval [CI] 5.84-8.17, p=0.0001), independent of significant associations with female sex, age, diabetes mellitus, office systolic BP, antihypertensive and antiplatelet treatment. In contrast, only a 17% increased prevalence of carotid plaques (OR=1.17; 95% CI 1.02-1.33, p=0.02) was found in obese patients independent of significant effect of male sex, older age and higher clinic systolic BP, an association that disappeared once effect of metabolic risk factors and related therapy was also considered.

Conclusions: In hypertensive patients participating in the Campania Salute Project, concomitant obesity was associated with a modestly increased prevalence of carotid plaques and a pronounced increase in prevalent LVH.

Keywords: Carotid atherosclerosis; Carotid ultrasound; Echocardiography; Hypertension; Left ventricular hypertrophy; Obesity.