The objective of this systematic review were to determine the effectiveness of lifestyle interventions on the prevalence of metabolic syndrome and on independent, modifiable risk factors for metabolic syndrome in people with metabolic syndrome. Randomised controlled trials published in English that evaluated the effectiveness of supervised, multifaceted lifestyle interventions in people with metabolic syndrome were included. Lifestyle interventions were defined as any supervised intervention involving both diet and exercise with or without other components, such as counselling. The risk of bias of the included trials was assessed using the PEDro scale, and these were used to determine the quality of the evidence using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach. Outcomes were prevalence of metabolic syndrome, risk factors for metabolic syndrome (eg, waist circumference, triglycerides, systolic blood pressure, body mass index), and quality of life. Adverse events were a secondary outcome.
15 articles reporting the results for 10 trials were included (n = 1,160 participants). Compared to usual care, there was moderate quality evidence that lifestyle interventions reduced the prevalence of metabolic syndrome (risk ratio 0.61, 95% confidence interval (CI) 0.38 to 0.96, 4 trials, 463 participants). There was moderate quality evidence that lifestyle interventions reduce waist circumference (mean difference -4.9 cm, 95% CI -8.0 to -1.7, 6 trials, 643 participants), low quality evidence that lifestyle interventions reduce triglycerides (standardised mean difference -0.46, 95% CI -0.88 to -0.04, 9 trials, 797 participants) and systolic blood pressure (mean difference -6.5 mmHg, 95% CI -10.7 to -2.3, 8 trials, 689 participants), and very low quality evidence that lifestyle interventions reduce body mass index (standardised mean difference -1.30, 95% CI -2.18 to -0.44, 9 trials, 798 participants). There was no difference for quality of life (standardised mean difference 1.68, 95% CI -0.23 to 3.58, 4 trials, 225 participants) and no trials reported adverse events.
Very low to moderate quality evidence supports the use of multifaceted, supervised lifestyle interventions to reduce the prevalence of metabolic syndrome and to reduce risk factors for this condition.
van Namen M, et al. Supervised lifestyle intervention for people with metabolic syndrome improves outcomes and reduces individual risk factors of metabolic syndrome: a systematic review and meta-analysis. Metabolism 2019;101:153988