Associations of Body Weight and Waist Circumference with Psychopathology, Substance Use, and Well-Being in an Adult Transdiagnostic Sample.

BACKGROUND

Prior studies have established inconsistent associations between body weight and mental health. However, most work has relied on body mass index (BMI) and examination of a single mental health variable. The present study examined associations of BMI and waist circumference with multiple mental health variables in a transdiagnostic psychiatric sample.

METHODS

Nursing staff measured waist circumference and calculated the BMI of 742 adults (54.6% female, 45.4% male) presenting for psychiatric treatment. Participants completed the Patient Health Questionnaire (PHQ-9), Generalized Anxiety Disorder Scale (GAD-7), Behavior and Symptom Identification Scale (BASIS-24), and Mental Health Continuum-Short Form (MHC-SF) as part of standard clinical monitoring. Suicide risk was assessed using the clinician-administered Mini International Neuropsychiatric Interview (M.I.N.I.). For curve fit estimation regression models, we entered BMI and waist circumference as independent variables separately; we entered seven dependent variables separately: 1) depression, 2) anxiety, 3) substance use, 4) self-harm, 5) interpersonal functioning, 6) well-being, and 7) suicide risk.

RESULTS

Increased BMI was associated with decreased well-being and increased depression. Increased waist circumference was associated with worse interpersonal functioning. Non-linear (quadratic) associations were observed between weight and depression, substance use, self-harm, and suicide.

LIMITATIONS: Most of the sample was White and only 2.6% was in the underweight category, limiting broad applicability of findings. Cross-sectional design precludes causal attributions.

CONCLUSIONS

Given associations between well-being, depression, interpersonal functioning, substance use, self-harm, and suicide with weight, findings may be used to inform mental health treatment, particularly by tailoring interventions to high-risk weight categories (underweight, obese) in psychiatric populations.