21 March 2013. A behavioral intervention effectively reduces weight in people with severe mental illness, according to a March 21 New England Journal of Medicine article on the "ACHIEVE" trial. Led by Gail Daumit of Baltimore’s Johns Hopkins University, the study found that overweight and obese psychiatric participants participating in a diet and exercise program experienced moderate and progressive weight loss over the course of 18 months.
Obesity represents a serious problem in psychiatric illnesses like schizophrenia and is a likely contributor to the increased mortality rates in this population (see SRF related news story). Like the general population, heart disease is the number one cause of death in mental illness, but obesity rates are double the national average. Metabolic syndrome due to antipsychotic medication use is thought to be the major contributor to obesity in psychiatric illness, although some studies have also reported increased obesity in drug-naïve patients, suggesting other factors like diet and exercise levels also play a role (see SRF related news story; SRF news story; Allison et al., 2009).
In the ACHIEVE (Randomized Trial of Achieving Healthy Lifestyles in Psychiatric Rehabilitation) study, participants included 291 overweight or obese adults with severe mental illness who were participating in one of 10 different outpatient psychiatric rehabilitation programs. The behavioral intervention was based on lifestyle changes known to be effective in the general population and adjusted to address cognitive deficits present in mental illness.
The program focused on reducing total calorie consumption and increasing calorie expenditure through healthy eating and moderate exercise. Subjects attended weight-management sessions conducted both individually and in a group setting, participated in group exercise classes, and tracked their behaviors to monitor progress. In contrast, those in the control group were given standard nutritional and fitness information at the start of the study, but were not exposed to targeted behavioral intervention.
Participants were randomly assigned to the behavioral intervention or control groups. Subjects had an average age of 45 years and were considered obese with an average body mass index (BMI) of 36. The majority of participants (58 percent) had a diagnosis of schizophrenia, while 22 percent had bipolar disorder and 12 percent had major depression. Weight changes were assessed at six, 12, and 18 months.
Those in the behavioral intervention group lost progressively more weight throughout the study, while participants in the control group did not lose significant weight. At six months, the intervention group had lost an average of three more pounds than the control group, a difference that was statistically significant. By 18 months, this difference in weight loss between the groups increased to seven pounds. In addition, a greater percentage of subjects in the intervention group maintained or decreased their weight by the end of the study (64 percent vs. 49 percent), and a higher percentage lost at least 5 percent of their total weight (38 percent vs. 23 percent).
Although seven pounds represents only modest weight loss, the authors point out that small changes in weight can produce health benefits such as a reduction in blood pressure, although they did not observe any significant changes in blood pressure or fasting lipid and glucose levels in the current study (but it was underpowered to detect such changes).
The progressive weight loss trajectory of the current study compares favorably with the results of some lifestyle intervention trials in the general population, in which weight is regained over time or maximum weight loss is achieved at six months and remains steady thereafter (Stevens et al., 2001; Whelton et al., 1998). In addition, weight loss in the current study was achieved despite ongoing use of psychotropic medications and continued psychiatric symptoms, which the authors suggest demonstrates that “overweight and obese adults with serious mental illnesses can make substantial lifestyle changes despite the myriad of challenges they face.”—Allison A. Curley.
Daumit GL, Dickerson FB, Wang N-Y, Dalcin A, Jerome GJ, Anderson CAM, Young DR, Frick KD, Yu A, Gennusa JV, Oefinger M, Crum RM, Charleston J, Casagrande SS, Guallar E, Goldberg RW, Campbell LM, Appel LJ. A behavioral weight-loss intervention in persons with serious mental illness. N Eng J Med 2013. Abstract