Prevalence of metabolic syndrome in Brazilian adults: a systematic review

BACKGROUND The metabolic syndrome (MS) is a complex of risk factors for cardiovascular disease. This syndrome increases the risk of diabetes, cardiovascular disease and all-cause mortality. It has been demonstrated that the prevalence of MS is increasing worldwide. Despite the importance of MS in the context of metabolic and cardiovascular disease, few studies have described the prevalence of MS and its determinants in Latin America. The present study aims to assess studies describing the prevalence of MS in Brazil in order to determine the global prevalence of the syndrome and its components. METHODS Systematic review. Searches were carried out in PubMed and Scielo from the earliest available online indexing year through May 2013. There were no restrictions on language. The search terms used to describe MS were taken from the PubMed (MeSH) dictionary: "metabolic syndrome x", "prevalence" and "Brazil". Studies were included if they were cross-sectional, described the prevalence of MS and were conducted in apparently healthy subjects, from the general population, 19-64 years old (adult and middle aged) of both genders. The titles and abstracts of all the articles identified were screened for eligibility. RESULTS Ten cross-sectional studies were selected. The weighted mean for general prevalence of MS in Brazil was 29.6% (range: 14.9%-65.3%). Half of the studies used the criteria for clinical diagnosis of MS proposed by the National Cholesterol Education Program Adult Treatment Panel III (NCEP-ATP III) (2001). The highest prevalence of MS (65.3%) was found in a study conducted in an indigenous population, whereas the lowest prevalence of MS (14.9%) was reported in a rural area. The most frequent MS components were low HDL-cholesterol (59.3%) and hypertension (52.5%). CONCLUSIONS Despite methodological differences among the studies selected, our findings suggested a high prevalence of MS in the Brazilian adult population.