Effect of an intervention for obesity and depression on patient-centered outcomes: an RCT.

INTRODUCTION: An integrated collaborative care intervention was successful for treating comorbid obesity and depression. The effect of the integrated intervention on secondary outcomes of quality of life and psychosocial functioning were examined, as well as whether improvements in these secondary outcomes were correlated with improvements in the primary outcomes of weight and depressive symptoms.

STUDY DESIGN: This RCT compared an integrated collaborative care intervention for obesity and depression to usual care. Data were analyzed in 2018.

SETTING/PARTICIPANTS: Adult primary care patients (n=409) with a BMI ≥30 (≥27 if Asian) and 9-Item Patient Health Questionnaire score ≥10 were recruited from September 30, 2014 to January 12, 2017 from primary care clinics in Northern California.

INTERVENTION: The 12-month intervention integrated a behavioral weight loss program and problem-solving therapy with as-needed antidepressant medications for depression.

MAIN OUTCOME MEASURES: A priori secondary outcomes included health-related quality of life (Short Form-8 Health Survey), obesity-specific quality of life (Obesity-Related Problems Scale), sleep disturbance and sleep-related impairment (Patient-Reported Outcomes Measurement Information System), and functional disability (Sheehan Disability Scale) at baseline and 6 and 12 months.

RESULTS: Participants randomized to the intervention experienced significantly greater improvements in obesity-specific problems, mental health-related quality of life, sleep disturbance, sleep-related impairment, and functional disability at 6 months but not 12 months. Improvements in obesity-related problems (β=0.01, 95% CI=0.01, 0.02) and sleep disturbance (β= -0.02, 95% CI= -0.04, 0) were associated with lower BMI. Improvements in the physical (β= -0.01, 95% CI= -0.01, 0) and mental health components (β= -0.02, 95% CI= -0.03, -0.02) of the Short Form-8 Health Survey as well as sleep disturbance (β=0.01, 95% CI=0.01, 0.02) and sleep-related impairment (β=0.01, 95% CI=0, 0.01) were associated with fewer depressive symptoms.

CONCLUSIONS: An integrated collaborative care intervention for obesity and depression that was shown previously to improve weight and depressive symptoms may also confer benefits for quality of life and psychosocial functioning over 6 months.