Obesity is associated with several somatic diseases and increased psychological burden. This study focused on two potential psychological predictors of the body mass index (BMI), childhood trauma and depressive symptoms.
We used three independent populations: two general population samples (Study of Health in Pomerania, SHIP-2, N = 1,657; SHIP-TREND-0, N = 3,278) and one patient sample (GANI_MED, N = 1,742). Childhood trauma was measured with the childhood trauma questionnaire (CTQ) and depression with the Beck Depression Inventory (BDI-II) in SHIP-2 and the Patient Health Questionnaire (PHQ-9) in SHIP-TREND-0 and GANI_MED. We investigated the impact of childhood trauma and depression on BMI. Furthermore, we used mediation analysis to assess whether depression was a significant mediator on the path from childhood trauma to adult BMI in each of the three samples.
In all the three populations, depressive symptoms exhibited a significant association towards higher BMI (p < 0.05). Childhood trauma was positively associated with BMI with significant associations in SHIP-TREND-0 (p < 0.001) and GANI_MED (p = 0.005). The relationship between CTQ and BMI was significantly partially mediated (p < 0.05) by depressive symptoms in SHIP-TREND-0 (38.0%) and GANI_MED (16.4%), in SHIP-2 results pointed in the same direction. All the trauma sub-dimensions, except sexual abuse, exhibited at least one significant association towards increased BMI in one of the samples.
Childhood trauma and depressive symptoms may be considered as causes of obesity. These results suggest that psychological treatments against obesity should address childhood maltreatment as well as depressive symptoms in their diagnostic assessment and could facilitate psychotherapeutic treatment when necessary.