Psychological distress as a determinant of changes in body mass index over a period of 10years.

Objective: To examine the longitudinal relationship between psychological distress and body mass index (BMI) changes over a period of five and ten years.

Method: Data were used from the Dutch, prospective, population based Doetinchem Cohort study over the period 1995/1999 until 2005/2009 (N=5504). Psychological distress was assessed using the Mental Health Inventory (MHI-5). BMI (kg/m(2)) was calculated from measured body height and body weight. GEE analyses were used to examine the relationship between psychological distress at baseline and BMI change, and the development of overweight over five years. Linear and logistic regression analyses were used to examine these relations over ten years.

Results: Psychological distress predicted an extra overall increase in BMI of 0.14kg/m(2) (95% CI 0.03-0.25) over five years and an increase of 0.18kg/m(2) (95% CI 0.01-0.35) over ten years, when comparing psychologically distressed participants to psychologically healthy participants. This was especially the case among persons with normal weight (five years; B=0.26kg/m(2), 95% CI=0.12-0.40/ten years; B=0.32kg/m(2) 95% CI=0.11-0.53) and moderate overweight (five years: B=0.18kg/m(2), 95% CI=0.02-0.35) at baseline. Psychological distress did not predict the development of overweight five and ten years later.

Conclusion: The results in this study indicated that psychological distress predicted an increased risk in gaining weight, but did not result in an increased risk for developing overweight.