Metabolic syndrome in Portugal: prevalence and implications for cardiovascular risk--results from the VALSIM Study

The metabolic syndrome (MS) is a constellation of risk factors of metabolic origin that is associated with increased risk of type 2 diabetes mellitus (DM) and cardiovascular disease (CVD). Several regional studies have been conducted to determine its prevalence, but they are insufficient to determine the situation nationally or to characterize overall cardiovascular risk in Portugal. To determine the prevalence of MS and each of its components in adult primary health care users in Portugal. The VALSIM Study, involving 719 general practitioners (GPs), was performed in a primary care setting, based on stratified distribution and proportional to the population density of each region of mainland Portugal and the islands of Madeira and the Azores. The first two adult patients scheduled for an appointment on a given day were invited to participate, irrespective of the reason for the consultation. After informed consent was obtained, a questionnaire on sociodemographic, clinical and laboratory data was completed by the GP. A previous diagnosis of coronary artery disease (CAD), stroke or DM was identified by the GP based on medical records. A diagnosis of MS was defined according to the NCEP ATP III criteria. Logistic regression multivariate analysis was used to assess the risk of MS according to age, body mass index (BMI), waist circumference (WC) and region of residence for each gender, and to determine the association of CAD, stroke and DM with gender, age, BMI, WC, blood pressure and previous diagnosis of hypertension (HT), fasting glucose and previous diagnosis of DM. The study included 16,856 individuals (mean age 58.1+/-15.1 years, 18-96 years; 61.62% women). The prevalence of MS adjusted for gender, age and size of region was 27.5% and showed regional variations, being highest in the Alentejo (30.99%) and lowest in the Algarve (24.42%). MS was more common among women and increased with age, BMI and WC. Independent protective factors were residence in the Algarve (odds ratio [OR]: 0.78; 95% confidence interval [CI] 0.66-0.92 p=0.002) or in Lisbon and Tagus Valley (OR: 0.83, 95% CI 0.77-0.91, p