Weight loss in mental illness

Joedy McCreary

May 4, 2013

John DiTraglia MD

Contributing Columnist

This week’s New England Journal of Medicine has the report of a study of weight loss intervention done with obese people with serious mental illness.(1) Using diet and activity, “lifestyle interventions,” they showed that people in this high risk group can achieve the same mediocre results that can be achieved by the rest of us.

Persons with serious mental illness, schizophrenia, bipolar disorder, and major depression, have an extremely high prevalence of obesity, nearly twice that of the overall population. There are several possible reasons for this, one of which is the drugs used to treat mental illness often cause weight gain and Type 2 diabetes. Furthermore, people with mental illness are often excluded from studies of weight loss interventions.

In this study, coordinated by departments at the Johns Hopkins University, 291 overweight and obese participants with an average weight of 226 pounds were recruited from 10 community psychiatric rehabilitation outpatient programs and randomly assigned to an intervention or control group. The intervention consisted of diet advice and a supervised exercise program. After 18 months the intervention group lost seven pounds more than the control group and 38 percent had achieved a weight loss of at least 5 percent of their start weight, compared to 23 percent of the control group. In other words 62 percent didn’t manage at least 5 percent weight loss.

One interesting observation was that the intervention group continued to lose weight throughout the 18 month study period. Studies like this usually result in the most weight loss by six months and then a regain of some of the weight lost after that. These authors conjecture that, “One possible explanation is that persons with serious mental illness take longer than those without..to engage in an intervention and make requisite behavioral changes.”

Finally they conclude that these results show that obese adults with serious mental illness can and should try to make these lifestyle changes to impact their high medical risks.

1.Daumit G et al. A behavioral wieght-loss intervention in persons with serious mental illness. N Engl J Med 2013;368:1594-602.