Bone mineral density, markers of bone turnover, and cytokines in young women with borderline personality disorder with and without comorbid major depressive disorder

Objective: The pathogenesis of bone loss in major depressive disorder is a matter of debate. Studies of bone loss in nonpsychiatric medical disorders have found an association between the activation of osteoclastic cells and an imbalance of pro- and antiinflammatory cytokines. Since major depressive disorder is also associated with alterations in serum cytokine concentrations, the authors hypothesized that bone loss in patients with major depressive disorder and comorbid borderline personality disorder may be associated with cytokines capable of activating osteoclastic cells. Method: Twenty-two patients with borderline personality disorder and comorbid current or lifetime major depressive disorder were compared with 16 patients with borderline personality disorder who did not have major depressive disorder and 20 healthy volunteers. Bone mineral density was assessed by means of dual-energy x-ray absorptiometry. Markers of bone turnover as well as endocrine and immune measures were determined. Results: The bone mineral density of 10 patients with borderline disorder plus current major depressive episode was significantly lower than that of the healthy subjects and the patients with borderline personality disorder without depression. Values of crosslaps, osteocalcin, serum cortisol, tumor necrosis factor-alpha (TNF-alpha), and interleukin-6 were significantly higher in the patients with borderline disorder plus current major depressive episode than in the healthy subjects. Crosslaps correlated positively with TNF-a but negatively with bone mineral density at the lumbar spine. Patients with borderline personality disorder who did not have current or lifetime depression displayed no alterations of either bone mineral density or the immunological and hormonal measures examined. Conclusions: Young women with co-morbid borderline personality disorder and major depressive disorder have an elevated risk for osteoporosis. Borderline personality disorder per se is not associated with low bone mineral density. These data suggest that the immune and endocrine disturbances associated with depressive disorders in the context of borderline personality disorder may play a role in the pathophysiological process underlying bone loss in the patients studied.