A behavioral weight-loss intervention significantly reduced excess weight in adults who had serious mental illness, according to a study published online March 21 in the New England Journal of Medicine.
This intervention, which was specifically tailored to the needs of people with mental illness, allowed steady weight loss that progressed over the 18-month duration of the study. In contrast, most studies of lifestyle interventions in the general population show an early peak in weight loss, often followed by weight regain.
These findings suggest that "despite substantial challenges, persons with serious mental illness are able to lose weight with a tailored intervention," said Dr. Gail L. Daumit of the Welch Center for Prevention, Epidemiology, and Clinical Research, Johns Hopkins University, Baltimore, and her associates.
Courtesy of National Cancer Institute
A healthy diet and exercise can significantly reduce excess weight in adults who have serious mental illnesses.
The prevalence of obesity is nearly twice as high among people with serious mental illness as among the general population. Mortality is two to three times higher, and cardiovascular disease is the primary cause of death in the seriously mentally ill.
Several factors contribute to this high prevalence. Unhealthy diets and physical inactivity are common in this patient population, and many psychotropic medications cause weight gain. Given their often low socioeconomic status, many people with serious mental illness also have reduced access to healthier, more-expensive foods and to safe, affordable places to exercise.
In addition, the stigma associated with mental illness also might make patients reluctant to participate in mainstream physical activities. And many have impairments in memory and executive function as well as psychiatric symptoms that "impede learning and the adoption of new behaviors," said Dr. Daumit, who also is affiliated with Johns Hopkins Bloomberg School of Public Health, and her colleagues.
They tested the effectiveness of an intervention that addressed these needs in the ACHIEVE (Achieving Healthy Lifestyles in Psychiatric Rehabilitation) clinical trial. The trial involved 291 overweight or obese adults who were participating in seven community outpatient psychiatric rehabilitation programs.
Such programs typically offer vocational and skills training, case management, and other services to the mentally ill; they usually have commercial kitchens that provide meals and snacks, as well as communal spaces suitable for group exercise.
"Program enrollees often attend these programs multiple times each week, which facilitates the delivery of lifestyle interventions that involve frequent contact," the researchers said (N. Engl. J. Med. 2013 March 21 [doi:10.1056/NEJMoa1214530]).
A total of 144 study subjects were randomly assigned to receive the intervention and 147 to a control group that received no intervention. The mean subject age was 45 years. Approximately half of the subjects were men, and 38% were black.
Nearly 80% of the study population was unable to work. A total of 58% had schizophrenia or schizoaffective disorder, 22% had bipolar disorder, and 12% had major depression. Patients were taking a mean of three psychotropic medications each.
The intervention addressed deficits in memory and executive function by dividing information into small components and by frequently repeating practice of skills.
Group and individual weight-management sessions focused on cutting caloric intake, especially by avoiding sugary drinks and junk food; consuming five servings of fruits and vegetables every day; controlling portion size; and eating healthy snacks.
Group exercise sessions focused on moderate-intensity aerobic exercise that gradually increased in duration and intensity.
The mean net weight loss increased over time only for patients who participated in the intervention. This loss was 1.8 kg at 6 months, and 3.4 kg at the completion of the trial. Although modest, this amount "compares favorably with weight loss in lifestyle-intervention trials in the general population" and has been associated with benefits such as reducing the risk of cardiovascular disease, Dr. Daumit and her associates said.
Participants in the intervention group continued to lose weight after 6 months and did not regain any weight, even when they attended fewer weight-management and exercise sessions over time. "One possible explanation is that persons with serious mental illness take longer than those without serious mental illness to engage in an intervention and make requisite behavioral changes," the investigators said.
"Our results show that overweight and obese adults with serious mental illness can make substantial lifestyle changes despite the myriad challenges they face," and that similar interventions should be implemented for this high-risk population, they added.
The study was funded by the National Institute of Mental Health. No conflicts of interest were reported.