Effect of selective serotonin reuptake inhibitors on markers of bone loss

Several preclinical and clinical studies show that selective serotonin reuptake inhibitors (SSRI's) are associated with bone loss and an increase in fracture risk, not many reports on their effect on bone turnover markers. This cross-sectional study evaluated the effect of SSRIs treatment on bone turnover markers in Indian population for the first time. Inclusion criteria were subjects of either sex and age 18-45 years undergoing treatment with an SSRI for at least 3 months, regardless of the indication. The results were compared with age-matched healthy controls. A total of 141 subjects were screened out of which 85 were enrolled, 44 in treatment and 41 in the control group. Serum Procollagen Type 1 Amino Terminal Propeptide (P1NP) levels were decreased in patients on SSRI treatment whereas no change was observed in the beta-C-terminal telopeptide (β-CTX) and receptor activator of nuclear factor kappa-Β ligand (RANKL) levels suggesting that these drugs can reduce bone formation but not resorption. Patients on SSRI treatment also showed reduced pCREB levels indicating that reduced bone formation is possibly through the gut mediated pathway. Our study suggests that SSRIs treatment at therapeutic doses may have a deteriorating effect on bone requiring caution in patients with additional risk factors.