Clinically Significant Improved Fitness and Weight Loss Among Overweight Persons With Serious Mental Illness

An RCT compared the 12-month In SHAPE fitness mentor program with a control condition involving fitness club membership and education. In SHAPE is a health promotion intervention consisting of a free fitness club membership and a health mentor. The mentor has basic certification as a fitness trainer and has received training for providing instruction on principles of healthy eating and nutrition and for tailoring individual wellness plans to the needs of persons with serious mental illness. Before enrollment, participants were required to obtain medical clearance by their primary care provider. After conducting comprehensive lifestyle and fitness evaluations, the health mentors developed personalized fitness plans using shared goal setting. Thereafter, they met with participants once a week for 45–60 minutes at a local fitness club (YMCA) and provided fitness coaching, support, and reinforcement of physical activity. The nutrition component focused on healthy eating as opposed to caloric restriction and involved discussions at each session, individual meetings with a registered dietitian, and group cooking classes or grocery store tours (or both), depending on participant goals and preferences.

The fitness club membership and education comparison condition also consisted of a free membership to the same local fitness club and included introduction to the exercise equipment and educational materials on the health benefits of exercise and healthy diet. This RCT did not use a usual care control group because usual care does not afford year-round safe and accessible opportunities for physical activity and therefore would not have represented a fair comparison with the In SHAPE program. In addition, we were primarily interested in evaluating the effectiveness of health mentors separate from access to a fitness club. Participants in both arms continued to receive their usual mental health services. Blinded outcome assessments were conducted at baseline and three, six, nine, and 12 months later.

Inclusion criteria were age 21 or older; diagnosis of major depression, bipolar disorder, schizoaffective disorder, or schizophrenia, (based on the Structured Clinical Interview for DSM–IV); serious mental illness, defined by an axis I disorder and persistent impairment in multiple areas of functioning (such as work, school, and self-care) (13); body mass index (BMI) >25; and ability and willingness to provide informed consent for participation. Participants must also have been on stable pharmacological treatment, defined as receiving the same psychiatric medications over the prior two months. Exclusion criteria were residing in a nursing home or other institution, primary diagnosis of dementia or significant cognitive impairment as determined by a Mini-Mental Status Exam (14) score <24, terminal illness expected to cause death within one year, or current diagnosis of substance dependence (based on the substance abuse module of the Structured Clinical Interview for DSM–IV).

Participants assigned to In SHAPE did not differ significantly from those assigned to fitness club membership and education on demographic, diagnostic, or baseline measures (Table 1). Equivalent 12-month follow-up retention and attrition (78%; N=52 in each group) emerged for both groups [see CONSORT diagram online].

Results of intent-to-treat analyses at the three-, six-, nine-, and 12-month follow-ups are listed in Table 2. Significant differences in our primary outcome of cardiorespiratory fitness were found for In SHAPE compared with fitness club membership and education based on the 6MWT. At the 12-month follow-up, In SHAPE was associated with an overall mean increase of 97.3 feet, in contrast to a decrease of 20.0 feet in the comparison group, for a between-group difference of 117.3 feet (35.8 m). No differences in mean weight change or BMI were observed between groups. From baseline to 12-month follow-up, there were no significant mean differences in weight or BMI in either group. Figure 1 shows the proportion of participants achieving clinically significant changes in fitness, and Figure 2 highlights those achieving clinically significant changes in weight loss. Over twice as many In SHAPE compared with control group participants realized clinically significant improvements in cardiorespiratory fitness, defined as >50-m gain on the 6MWT at three- and 12-month follow-ups. Similar proportions of In SHAPE and comparison groups achieved clinically significant weight loss of ≥5% body weight (30% and 33%, respectively) at the 12-month follow-up. Weight changes were not associated with baseline antipsychotic type or psychiatric medication’s propensity to cause weight gain.

In SHAPE was significantly associated with achieving both clinically significant improved fitness and weight loss. At the 12-month follow-up, 49% (N=22 of 45) of In SHAPE participants experienced reduced cardiovascular risk by achieving either clinically significant improved fitness or weight loss and 24% (N=11 of 45) had both an increase on the 6MWT of at least 50 m and a 5% or greater reduction in body weight (χ²=10.42, df=1, p=.003). In contrast, 41% (N=19 of 46) of the comparison group participants reduced their risk by either measure, but only 9% (N=4 of 46) achieved both (χ²=1.04, df=1, p=.42)—nearly a threefold difference compared with In SHAPE.

Over the 12-month duration of the program, 40% (N=27) of In SHAPE participants attended a minimum of half of their weekly visits to the YMCA, compared with only 11% (N=7) of participants in the fitness club membership and education group (χ²=15.41, df=1, p<.001). At the 12-month follow-up, In SHAPE contributed to more than three times greater attendance at the YMCA and more than twice as much moderate to vigorous exercise (192 versus 95 minutes per week). In SHAPE was also associated with significantly greater total MET minutes of vigorous activity. Significant differences emerged between In SHAPE and the comparison group with respect to three dietary behavior subscales of the WLB-SOC scale, including reduced consumption of dietary fat, better portion control, and increased intake of fruits and vegetables.

The In SHAPE health mentor program, compared with fitness club membership and education, was associated with greater fitness club attendance, more participation in physical exercise, increased vigorous physical activity, and greater improvement in dietary habits. There were no differences in mean weight and BMI among In SHAPE participants from baseline to 12-month follow-up or when compared with fitness club membership and education participants, as hypothesized. However, compared with participants in the control group, over twice as many In SHAPE participants achieved clinically significant improvements in cardiorespiratory fitness. Of note, this improvement was obtained early in the intervention, at three months (46% versus 20%), and was maintained as of the 12-month follow-up (40% versus 20%). In SHAPE participants exceeded the threshold for engaging in the ≥150 minutes or more of moderate to vigorous physical activity each week that has been associated with an 86% reduction in risk of all-cause mortality (11). These findings suggest that a mentoring approach can be effective in rapidly reducing cardiovascular mortality risk for overweight and obese individuals with serious mental illness by significantly improving fitness.

Prior studies indicate that persons with serious mental illness have low levels of confidence in their ability to participate in exercise, especially during symptomatic periods (37,38), and that providers can be a source of motivation in overcoming obstacles to health behavior change (37,39). Our results demonstrate that a health mentor intervention may help to overcome the motivational challenges and low self-efficacy often experienced by persons with serious mental illness. In SHAPE was associated with greater improvement in participants’ motivational “readiness” to change dietary practices, a critical and necessary step toward adopting and maintaining healthy dietary behaviors (40).

The absence of statistically significant changes in weight and BMI among In SHAPE participants compared with fitness club membership and education differs from some prior RCTs that have reported significant (although not clinically significant) mean differences in weight loss between intervention and control groups (41–50). In addition, many weight management interventions focus on reducing caloric intake and monitoring intake with daily food diaries (51,52), whereas In SHAPE health mentors provided advice on healthy eating and improving nutrition but did not focus on reducing calories. Our results confirm that physical activity alone is of limited benefit in inducing weight loss (53). However, it is noteworthy that almost one-third of participants in both study groups achieved clinically significant weight loss (5% or more of body weight), illustrating the common finding of heterogeneous outcomes for lifestyle interventions for obesity.

Acknowledging that an individual health club membership and personal trainer can be costly, we calculated the cost of providing the In SHAPE program, consisting of a health mentor employed by the mental health center and a discounted, bulk-rate fitness club membership. The per-person annual cost of In SHAPE ranges from $1,450 (rural) to $1,692 (urban). To put this into perspective, based on an estimate of the additional annual health care costs for diabetes in schizophrenia in 2012-adjusted dollars ($3,015) (54), the five-year cost as a chronic condition amounts to $15,075. The health care savings achieved over five years by preventing diabetes for approximately 10% of In SHAPE participants (9.7%−11.2%) would offset the costs of providing In SHAPE as a 12-month intervention. A subsequent study is under way that will include a formal analysis of the costs of the In SHAPE program and potential savings in health care expenditures.

Limitations of this study warrant caution when interpreting the results. First, the study design did not evaluate the effectiveness of In SHAPE or fitness club membership and education compared with usual care. However, the conditions we used allowed us to evaluate the impact of the mentor on engagement in vigorous exercise and improvement in cardiorespiratory fitness. Second, the diagnostically heterogeneous nature of the study sample has the strength of broad clinical application but did not allow evaluation of potential differences in response that might be associated with psychiatric diagnosis. Third, this study was conducted at a single site in New Hampshire, which creates the possibility that site-specific factors may have influenced the results. However, the use of several health mentors reduced the potential that the findings are attributable to the characteristics or skills of a single health mentor. Fourth, although the study sample represented overweight and obese adults with serious mental illness, participants were predominantly female (62%) and white (92%). Hence, the results do not necessarily generalize to an ethnically diverse or more gender-balanced sample.

The results of this study suggest that integrated provision of a fitness program that includes a health mentor as a component of community mental health services is feasible and associated with clinically significant reduction in cardiovascular risk. Although In SHAPE did not contribute to greater mean weight loss or reduction in BMI when compared with fitness club membership and education, the program was associated with positive health behavior change, including increased physical exercise and vigorous activity and progression in revising dietary habits. In contrast to prior reports, a unique strength of this study is our evaluation of clinically significant weight loss and fitness outcomes, in addition to mean differences. Almost half (49%) of In SHAPE participants at 12 months achieved clinically significant improvement in either cardiorespiratory fitness or weight loss, and 24% achieved both. Finally, despite these encouraging results, the rest of the In SHAPE participants did not achieve clinically significant risk reduction at the one-year follow-up. It is likely that individually tailored health promotion interventions will be needed to optimize outcomes. Future large-scale studies or pooled analyses across multiple investigations should be considered to identify individual predictors of treatment response.

This study was supported by grant R01 DD000140 and CDC Cooperative Agreement 1U48DP001935-0 from the Centers for Disease Control and Prevention and by grants K24MH066282 and K23MH080021 from the National Institute of Mental Health.

Dr. Pratt, Dr. Barre, and Mr. Jue have received payments from Ken Jue Consulting to provide training in In SHAPE at community mental health centers (nonresearch sites). The other authors report no competing interests.