The metabolic syndrome and cardiovascular risk in the British Regional Heart Study

Abstract

Objective: To evaluate the metabolic syndrome as an overall risk assessment tool for cardiovascular disease (CVD) and diabetes in middle-aged British men.

Design: Prospective study.

Subjects: A total of 5128 men aged 40-59 years with no history of CVD or diabetes drawn from general practices in 24 British towns and followed up for 20 years.

Results: The metabolic syndrome (National Cholesterol Expert Panel definition) is associated with a significant increase in risk of total CHD (myocardial infarction, angina or CHD death) (relative risk (RR), 95% CI: 1.57, 1.39-1.97), stroke (1.61, 95% CI: 1.26-2.06) and type 2 diabetes (3.57, 95% CI: 2.83-4.50) and is a far stronger predictor of diabetes than of total CHD and stroke in middle-aged men. The metabolic syndrome was inferior to the Framingham Risk Score in predicting total CHD or major CVD over 20 years (area under the curve (AUC) 0.58 vs 0.66 for both CHD and CVD; P<0.0001 for difference) but was superior in predicting diabetes (AUC 0.70 vs 0.60; P<0.001). However, absolute risk of developing CVD or diabetes over 20 years in those with three or more abnormalities was very high, ranging from 41.8% in those with three abnormalities to over a 50% chance in those with four of five abnormalities, comparable to the absolute incidence rates in the top 2 fifths of the Framingham distribution.

Conclusion: While the initial aim to use the metabolic syndrome to improve risk prediction of CHD has been disappointing, the syndrome identifies patients at high risk of both diabetes and CVD who may derive benefit from lifestyle intervention.