IMPACT OF BODY MASS INDEX AND WAIST CIRCUMFERENCE ON THE RISK OF CARDIOVASCULAR EVENTS AND ALL-CAUSE DEATH IN A GENERAL POPULATION: PP.7.283

Abstract

Introduction: An elevation in body mass index (BMI) and waist circumference (WC) is associated with an increased cardiovascular (CV) risk. It is debated, however, whether and to what extent this depends on the body fat increase “per se” or on the related cardiometabolic alterations. Methods: In 2005 subjects of both genders (25–74 years) randomly selected from the general population of Monza (Italy), we assessed BMI, WC, office, home and 24- hour systolic and diastolic blood pressure (SBP/DBP), total/HDL-cholesterol, triglycerides and plasma glucose. Correlations were sought between the various variables. The impact of BMI and waist circumference (WC) on the incidence of CV events and all-cause was estimated by recording during a follow-up period of 148 months CV events (fatal and non fatal) and all-cause deaths. Results: Mean BMI was 25.6 ±4.26 (SD) Kg/m2 and mean WC was 85.6 ±12.40 (SD) cm. Age, office, home, 24-hour SBP/DBP and pulse pressure, serum cholesterol, serum triglycerides and glycemia were directly and significantly (P < 0.0001) related to BMI and WC, while an inverse significant relationship was detected with HDL-cholesterol. Unit increases in both BMI and WC were associated, both in males and in females, with a significant increase in the risk of all-cause death and CV events [BMI: hazard ratio (HR)1.068, confidence intervals (CI) 1.039–1.099 and 1.081, CI 1.048–1.115; WC: HR 1.035, CI 1.026–1.045 and 1.038, CI 1.027–1.048, respectively (p < 0.0001)]. Statistical significance was lost, however, following data adjustment for confounders (age, gender, 24-hour SBP, serum cholesterol, blood glucose, previous CV events). At the stepwise regression analysis age and history of previous CV events were the variables most closely related to CV and all-cause mortality. Conclusions: The adverse CV effects related to an elevation in body fat depot depend on the cardiometabolic alterations related to the BMI increase rather than on BMI or WC elevation “per se”. In the general population, the patients' age and history of previous events are the major determinants of the CV risk.