Few studies have evaluated the associations between the metabolic syndrome (by any definition) and mortality. This study examined the age- and sex-specific prevalence of the metabolic syndrome and its association with all-cause and cardiovascular mortality in nondiabetic European men and women.
The study was based on 11 prospective European cohort studies comprising 6156 men and 5356 women without diabetes and aged from 30 to 89 years, and had a median follow-up of 8.8 years. A modification of the World Health Organization definition of the metabolic syndrome was used. The subjects were considered to have the metabolic syndrome if they had hyperinsulinemia and 2 or more of the following: obesity, hypertension, dyslipidemia, or impaired glucose regulation; however, other definitions were also studied. Hazard ratios for all-cause and cardiovascular mortality were estimated with Cox models in each cohort. Meta-analyses were performed to assess the overall association of the metabolic syndrome with mortality risk.
The age-standardized prevalence of the metabolic syndrome was slightly higher in men (15.7%) than in women (14.2%). Of the 1119 deaths recorded during follow-up, 432 were caused by cardiovascular disease. The overall hazard ratios for all-cause and cardiovascular mortality in persons with the metabolic syndrome compared with persons without it were 1.44 (95% confidence interval [CI], 1.17-1.84) and 2.26 (95% CI, 1.61-3.17) in men and 1.38 (95% CI, 1.02-1.87) and 2.78 (95% CI, 1.57-4.94) in women after adjustment for age, blood cholesterol levels, and smoking.
The overall prevalence of the metabolic syndrome in nondiabetic adult Europeans is 15%. Nondiabetic persons with the metabolic syndrome have an increased risk of death from all causes as well as cardiovascular disease.