Objective: Using the criteria proposed in the "Third Report of the National Cholesterol Education Program Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults" (APT-III), this study describes the prevalence of the metabolic syndrome and of its individual features, using a representative sample of adults living in Porto.
Design: Cross-sectional study.
Participants: Random sample of 1436 adult residents of Porto (873 women and 563 men).
Methods: All participants answered a structured questionnaire comprising information on social demographic, behavioral and clinical characteristics. Weight, height and waist circumference were measured. Blood pressure was recorded and a fasting blood sample collected. Metabolic syndrome was defined in accordance with ATP III as the presence of 3 or more of the following characteristics: waist circumference > 102 cm in men and > 88 cm in women, triglyceride levels > or = 150 mg/dL, high density lipoprotein cholesterol < 40 mg/dL in men and < 50 mg/dL in women, blood pressure > or = 130/85 mmHg and fasting serum glucose > or = 110 mg/dL. Proportions were age-adjusted using the standard European population, and were compared using the chi-square test.
Results: The gross prevalence of metabolic syndrome in this sample was 23.9% (27.0% in females and 19.1% in males) and 14.5% after age-adjustment using the European standard population. The prevalence of the syndrome increased with age in both genders, reaching its peak at 60-69 years of age (35.0% in women and 32.9% in men). A high prevalence of blood pressure > or = 130/85 mmHg was found in both genders (68.0% in females and 73.5% in males), the least common factor being fasting serum glucose > or = 110 mg/dL (6.0% in females and 8.2% in males).
Conclusion: This first estimate of metabolic syndrome prevalence in a representative sample of adults living in a large Portuguese urban area showed that the syndrome is very frequent and typically associated with high blood pressure values, which is in agreement with the high cardiovascular morbidity and mortality among the Portuguese.