The metabolic syndrome: similar deleterious impact on all-cause mortality in hypertensive and normotensive subjects

OBJECTIVES: Few data are available on the impact of the metabolic syndrome on all-cause mortality risk according to the presence of hypertension. Our aim was to evaluate the 5-year impact of the metabolic syndrome, according to blood pressure status, on all-cause mortality risk in a large French population. METHODS: The study population included 39 998 men and 20 756 women with no personal history of cardiovascular disease, who had a health check-up at the IPC Center (Paris, France) between 1999 and 2002, and who were followed up for 4.7 +/- 1.2 years. The metabolic syndrome was defined according to the National Cholesterol Educational Program classification (2001). Cox regression models were used to evaluate risk of all-cause mortality after adjustment for age, sex, classical risk factors and socioeconomic categories. Subjects were classified according to blood pressure status: hypertensive subject (systolic blood pressure > or =140 mmHg and/or diastolic blood pressure > or =90 mmHg or treatment) and normotensive subject. RESULTS: The risk of all-cause mortality associated with the metabolic syndrome was 1.50 (1.24-1.82) hazard ratio (HR) (95% confidence interval). The risk of all-cause mortality associated with the presence of hypertension was 1.60 (1.38-1.85). During the 4.7 years of follow-up, the impact of the metabolic syndrome was similar among normotensive and hypertensive subjects HR: 1.09 (0.68-1.75) and 1.40 (1.13-1.74), respectively, P for interaction = 0.35. CONCLUSION: The findings from this study show that, in a large middle-aged French population, the metabolic syndrome has the same deleterious impact on all-cause mortality in hypertensive subjects and normotensive subjects.