Background:
Selective serotonin reuptake inhibitors (SSRIs) are a first-line treatment for depression. SSRIs have been reported to regulate serotonin (5-HT) receptors and the transporter 5-HTT on osteoclasts and osteoblasts. Previous studies reporting reduced bone mineral density (BMD) among SSRI users may have been confounded by the effects of depression.
Methods:
Among women enrolled in the Geelong Osteoporosis Study (GOS), a history of depression was ascertained by clinical interview (SCID-I/NP). BMD was measured at the PA spine, hip, total body and forearm using dual-energy absorptiometry, and medication use was self-reported.
Results:
Among 177 women with a lifetime history of depression, current users of bisphosphonates, glu-cocorticoids, hormone therapy and other antidepres-sants were excluded (n = 49). Of the remaining 128 (median age 51.5 years, range 30–74), 26 (20.3%) reported current SSRI use. SSRI users were shorter than nonusers (1.59 ± 0.06 vs. 1.62 ± 0.06 m, P = 0.01); however, there were no differences in age, weight or smoking history. Using analysis of covariance and controlling for age, weight, height and smoking history, BMD among SSRI users was 5.7% lower at the femoral neck (0.977 ± 0.015 vs. 0.922 ± 0.025 g/cm2, P = 0.03), 6.1% lower at the trochanter (0.813 ± 0.010 vs. 0.763 ± 0.021 g/cm2, P = 0.04) and 4.4% lower at the midforearm (0.745 ± 0.009 vs. 0.712 ± 0.015 g/cm2, P = 0.03) than nonusers. No differences in BMD were detected at other sites.
Conclusions:
Among women with a lifetime history of depression, SSRI use is associated with reduced BMD. Although the mechanism remains unclear, these observations are consistent with a role for the serotonergic system in regulating bone metabolism.
