Lifestyle Intervention for Young Adults With Serious Mental Illness

The objective of this study is to evaluate the effectiveness of a group-based lifestyle intervention (PeerFIT) supported by mobile health (mHealth) technology and social media to promote weight loss and improved fitness in young adults with serious mental illness (SMI). The study is a two-arm randomized controlled trial conducted in real world mental health settings to evaluate the effectiveness of the 12-month PeerFIT intervention compared to Basic Education in fitness and nutrition supported by a wearable Activity Tracking device (BEAT) in achieving clinically significant improvements in weight loss and cardiorespiratory fitness. The investigators will enroll 144 overweight and obese (BMI ≥ 25) young adults ages 18 to 35 with SMI attending one of two community mental health who are interested in losing weight and improving fitness. The investigators hypothesize that PeerFIT compared to BEAT will be associated with a greater proportion of participants who achieve cardiovascular risk reduction at 6 and 12 months follow-up as indicated by either clinically significant weight loss (5% or greater) or increased fitness (>50 m on the six-minute walk test). The investigators also hypothesize that PeerFIT compared to BEAT will be associated with greater improvements in A1c and lipid profiles at 6 and 12 months follow-up. They will also investigate two theoretical mechanisms of action hypothesized to account for greater weight loss and increased cardiorespiratory fitness among participants assigned to PeerFIT: 1) improved self-efficacy and 2) increased peer support for health behavior change. The investigators hypothesize that the relationship between PeerFIT and weight loss and improved fitness will be mediated by improved self-efficacy and peer support for health behavior change.

Inclusion criteria

• Young adults ages 18 to 35
• Chart diagnosis of schizophrenia, schizoaffective disorder, bipolar disorder, or major depression
• Overweight or obese defined as BMI ≥25
• Enrolled in treatment at the agency for at least 3 months prior to study recruitment
• Have not started taking Clozapine or Olanzapine antipsychotic medications over the prior 2 months (dose changes are allowed)
• Able and willing to give written informed consent to participate in the study or able to assent with guardian consent
• Willingness to be randomized to either of the two conditions
• Able and willing to attend the weekly 60-minute weight management session, participate in the weekly 1-hour physical activity sessions, and use the Facebook and mHealth (i.e., Fitbits and text messaging) components of the PeerFIT program

Exclusion criteria

• Medical contraindication to weight loss (e.g., cancer, stroke, liver failure)
• Medical conditions (e.g., diabetes, angina) that do not receive medical clearance by a primary care provider
• Major surgery planned or likely to occur within the next 6 months
• Prior or planned bariatric surgery
• Use of prescription weight loss medication within the past 6 months
• 5% or greater weight loss in 3 months prior to baseline
• Currently enrolled in another weight reduction program
• Pregnant or planning a pregnancy, or breastfeeding during study period
• Cognitive impairment sufficient to interfere with participant's ability to provide informed consent, complete study questionnaires, or participate in a group intervention as indicated by a Mini Mental Status Examination score <24
• Active substance use determined to be incompatible with participation in the intervention identified by screening questionnaire that assesses for excessive use according to intake limits by gender
• Use of anabolic steroids with the drug taken at least "most days of the week for the previous month"
• Planning to leave agency or move out of geographic area within 12 months
• People who are non-English speakers or who have major visual or hearing impairment will be excluded given the need to read the program materials and interact with technology.