Effectiveness of a lifestyle intervention on metabolic syndrome. A randomized controlled trial

BACKGROUND Intensive lifestyle intervention significantly reduces the progression to diabetes in high-risk individuals. OBJECTIVE It is not known whether a program of moderate intervention might effectively reduce metabolic abnormalities in the general population. DESIGN Two-arm randomized controlled 1-year trial. PATIENTS Three hundred and thirty-five patients participated from a dysmetabolic population-based cohort of 375 adults aged 45-64 years in northwestern Italy. MEASUREMENTS We compared the effectiveness of a general recommendation-based program of lifestyle intervention carried out by trained professionals versus standard unstructured information given by family physicians at reducing the prevalence of multiple metabolic and inflammatory abnormalities. RESULTS At baseline, clinical/anthropometric/laboratory and lifestyle characteristics of the intervention (n=169) and control (n=166) groups were not significantly different. The former significantly reduced total/saturated fat intake and increased polyunsaturated fat/fiber intake and exercise level compared to the controls. Weight, waist circumference, high-sensitivity C-reactive protein, and most of the metabolic syndrome components decreased in the intervention group and increased in the controls after 12 months. Lifestyle intervention significantly reduced metabolic syndrome (odds ratio [OR]=0.28; 95% CI 0.18-0.44), with a 31% (21-41) absolute risk reduction, corresponding to 3.2 (2-5) patients needing to be treated to prevent 1 case after 12 months. The intervention significantly reduced the prevalence of central obesity (OR=0.33; 0.20-0.56), and hypertriglyceridemia (OR=0.48; 0.31-0.75) and the incidence of diabetes (OR=0.23; 0.06-0.85). CONCLUSION A lifestyle intervention based on general recommendations was effective in reducing multiple metabolic/inflammatory abnormalities. The usual care by family physicians was ineffective at modifying progressive metabolic deterioration in high-risk individuals.