Insecure attachment style predicts low bone mineral density in postmenopausal women. A pilot study

Major depressive disorder (MDD) and osteoporosis are two common disorders with high morbidity and mortality rates. Conflicting data have found associations between MDD and low bone mineral density (BMD) or osteoporosis, although causative factors are still unclear. A pilot study was designed with the aim to assess the relationship between MDD and BMD in postmenopausal women with MDD compared to healthy volunteers. We hypothesized that attachment style (AS) mediated this relationship.The sample was made of 101 postmenopausal women, 49 with MDD and 52 age-matched healthy volunteers. Structured clinical interview and Beck Depression Inventory (BDI) were performed to assesse MDD. AS was evaluated using the Relationship Questionnaire (RQ). BMD was measured by dual energy X-ray absorptiometry.The univariate analysis showed that women with MDD had lower BMD values as compared to healthy volunteers. In the regression models MDD diagnosis and BDI score were not significant predictors of low BMD. The “preoccupied” pattern of insecure AS was a significant, independent predictor of decreased BMD in all skeletal sites: lumbar spine (p=0.008), femoral neck (p=0.011), total hip (p=0.002).This is the first study exploring the relationship between AS, MDD and BMD. Our results support the link between MDD and low BMD. We found that insecure AS was a risk factor for decreased BMD, regardless of depression. Insecure AS may play a role in the relationship between MDD and BMD or may constitute a risk factor itself. Therapeutic interventions focused on AS could improve psychiatric disorders and physical diseases related to low BMD.