Use of SSRIs could lead to brittle bones in older patients

In 2 prospective cohort studies published in the Archives of Internal Medicine, researchers demonstrated that selective serotonin-reuptake inhibitor (SSRI) use, but not the use of other common antidepressants, was associated with a significant decrease in total hip and lumbar spine bone mineral density (BMD) among older patients compared with nonuse of antidepressants.

Key Points

In 2 prospective cohort studies published in the Archives of Internal Medicine, researchers demonstrated that selective serotonin-reuptake inhibitor (SSRI) use, but not the use of other common antidepressants, was associated with a significant decrease in total hip and lumbar spine bone mineral density (BMD) among older patients compared with nonuse of antidepressants.

SSRI USE AMONG OLDER WOMEN

In the first study, Diem et al evaluated >2,700 women who were enrolled in The Study of Osteoporotic Fractures. To be included in this analysis, participants were required to have hip BMD measurements taken, complete the Geriatric Depression Scale, and provide a medication history. Women who were taking both tricyclic antidepressants (TCAs) and SSRIs or who were taking other antidepressants were excluded from the study (n=122). The primary study end point was the change in mean total hip BMD in the time between the sixth and eighth clinical examinations, an average of 4.9 years.

After adjustment for potential confounders, SSRI use was associated with a greater yearly rate of bone loss at the total hip compared with nonuse (–0.82% vs –0.47%; P<.001). In contrast, the use of TCAs was associated with similar rates of bone loss at the total hip compared with nonuse after adjustment for potential confounders (–0.47% vs –0.47%; P=.99).

SSRI USE AMONG OLDER MEN

In the cross-sectional study performed by Haney et al, 5,995 men aged ≥65 years who were enrolled in the Osteoporotic Fractures in Men Study were evaluated. All study participants were required to have BMD measurements taken and to complete medication and demographics interviews. A mental component summary scale of the Medical Outcomes Study 12-Item Short-Form Health Survey (SF-12) was used to assess the patients' perceived mental health status. The primary outcomes were the total hip and lumbar spine BMDs.

A total of 5,708 men were nonusers of antidepressants; 160 men used SSRIs, 99 men used TCAs, and 52 men used trazodone.

The use of SSRIs was associated with a 3.9% lower total hip BMD and a 5.9% lower lumbar spine BMD compared with nonuse (P=.002 and P<.001, respectively). Total hip BMD and lumbar spine BMD differences among TCA users, trazodone users, and nonusers of antidepressants were not significant.

IMPACT OF THIS RESEARCH

"These associations are biologically plausible and clinically important," according to Elizabeth M. Haney, MD, who contributed to both studies. "Because SSRI use is prevalent in the general population, our findings have a potentially important public health impact."

The authors of both studies stressed that further research is needed to confirm these results.

In an accompanying editorial, Kenneth Saag, MD, MSc, stated that "In the case of the depressed patient, good clinical acumen and thoughtful adverse event monitoring can help avoid having healthier minds at the expense of sicker bones."

SOURCES

Diem SJ, Blackwell TL, Stone KL, et al. Use of antidepressants and rates of hip bone loss in older women: The Study of Osteoporotic Fractures. Arch Intern Med. 2007;167:1240–1245.

Haney EM, Chan BKS, Diem SJ, et al; for the Osteoporotic Fractures in Men Study Group. Association of low bone mineral density with selective serotonin reuptake inhibitor use by older men. Arch Intern Med. 2007;167:1246–1251.

Saag K. Mend the mind, but mind the bones!: Balancing benefits and potential skeletal risks of serotonin reuptake inhibitors [editorial]. Arch Intern Med. 2007;167:1231–1232.