Lifestyle intervention helps people taking antipsychotic medications lose weight and reduce diabetes risk

People taking antipsychotic medications for serious mental illnesses lost significant amounts of weight and improved their glucose levels by participating in a lifestyle-change program, according to a study funded by the National Institutes of Health and published online in the American Journal of Psychiatry.

Studies show that people with serious mental illnesses such as schizophrenia and bipolar disorder are already at higher risk for obesity and obesity-related diseases such as diabetes. The medications that control psychiatric symptoms can make these problems worse by stimulating appetite and thirst and causing metabolic changes that lead to additional weight gain.

This study involved 200 people who were either overweight or obese and were also taking antipsychotics for serious mental illnesses; half of the study participants were enrolled in a year-long lifestyle intervention, the other half served as the control group and did not participate in the intervention.

Intervention participants lost nearly 10 more pounds than those in the control group during the weight loss phase of the study. They regained some of their weight during the weight maintenance phase of the study, but still weighed about 6 pounds less than people in the control group by the end of the intervention.

Intervention participants were also more than twice as likely as those in the control group to have normal fasting glucose levels at the end of the intervention period, and they had fewer medical hospitalizations (6.7 percent compared to 18.8 percent).

"Our study is the first to show that a lifestyle intervention can help people with serious mental illness lose weight, reduce their diabetes risk, and reduce the need for medical hospitalizations," said lead author Carla Green, PhD, MPH, with the Kaiser Permanente Center for Health Research, in Portland, Oregon.

"Previous studies have shown moderate success with weight loss among this population, but no improvements in blood glucose levels or medical hospitalizations," added Green.

Dr. Green's study (called STRIDE) took place between 2009 and 2013 and included members of Kaiser Permanente Northwest and patients served by Cascadia Behavioral Healthcare or LifeWorks Northwest community mental health centers in the Portland Oregon Metropolitan Area.

During the 6-month weight-loss phase, intervention participants attended weekly, two- hour group meetings that included 20 minutes of physical activity. Participants learned how to keep food and exercise diaries, and they set goals for physical activity, eating habits and sleep quality. They also learned about the effects of psychiatric medications on their weight and were given specific advice about how to discuss this topic with their health care providers.

During the 6-month weight-maintenance phase of the trial, intervention participants attended monthly group meetings and received individual monthly telephone sessions with group leaders.

Those in the control group did not participate in the weight loss or weight maintenance group intervention, but were free to pursue alternative weight loss efforts.

All study participants attended a group orientation session and follow-up assessment visits to measure their weight, blood pressure and lab values, and all were referred to primary or urgent care if their values were outside normal ranges.

The STRIDE intervention was adapted from weight management and blood pressure control trials including the PREMIER trial and the DASH diet trial, which were designed for people without mental illness.

STRIDE participants lost between 9-12 pounds, which is comparable to the average weight loss of 10-15 pounds in the PREMIER trial. Study authors say this shows that if people with serious mental illness participate in intensive programs and are given the right tools and support they can lose the same amount of weight as people without serious mental illnesses.

Dr. Green's study was supported by a grant from the National Institute of Diabetes and Digestive and Kidney Diseases. (R18DK076775)

In addition to Dr. Green, study authors include Bobbi Jo Yarborough, PsyD; Michael Leo, PhD; Micah Yarborough, MA; Scott Stumbo, MA; Shannon Janoff, MPH; Nancy Perrin, PhD; Greg Nichols, PhD; and Victor Stevens, PhD; all from the Kaiser Permanente Center for Health Research in Portland, Oregon.