The life expectancy of severe mentally ill (SMI) patients is shortened up to 30years, due to cardiometabolic diseases, partly caused by unhealthy lifestyles behaviors. In residential facilities, adopting a healthy lifestyle is hampered by the obesogenic environment; an obesity promoting environment.

To determine, the effectiveness of a 12month lifestyle intervention addressing the obesogenic environment to improve cardiometabolic health of SMI residential patients.

The effectiveness of lifestyle interventions in psychiatry (ELIPS) trial is a multi-site, cluster randomized controlled pragmatic trial. Twenty-nine sheltered and long-term clinical care teams serving SMI patients in the Netherlands were randomized into intervention (n=15) or control (n=14) arm, including 736 patients (73% psychotic disorder, 63% male, 48±13years). The intervention aimed to improve the obesogenic environment using a small change approach with a focus on nutrition and physical activity. Primary outcome was waist circumference (WC) after three and twelve month's intervention. Secondary outcomes were BMI and metabolic syndrome.

General linear mixed models adjusted for age, gender, housing facility and antipsychotic medication showed that WC significantly decreased with 1.51cm (95%CI=−2.99;−0.04, Cohen's d=0.07) in the intervention group compared to control group after three months and tended to remain lower with 1.28cm (95%CI=−2.79; 0.23, Cohen's d=0.06) after twelve months. Metabolic syndrome Z-score decreased after three months with 0.225 SD (95% CI=−0.4038;−0.096, Cohen's d=0.20), mainly due to lower fasting glucose and WC. No significant effects were found on BMI.

A small change approach targeting the obesogenic environment of SMI residential patients reduces cardiometabolic risk.