Antidepressants May Speed Bone Loss
SSRIs Linked to Reduced Bone Density in 2 Studies
June 25, 2007 - Older men and women who take the most widely prescribed
antidepressants are at increased risk for bone loss, new research shows, but it
is unclear if the bone loss is caused by the drugs.
Two newly published studies -- one in men and the other in women -- appear
to link the use of selective serotonin reuptake inhibitor (SSRI)
antidepressants to age-related bone weakening.
In one study, older women who took SSRI antidepressants showed a 60%
acceleration in bone loss, compared with women who did not take
antidepressants, researcher Susan J. Diem, MD, MPH, tells WebMD.
The accelerated bone loss was not seen in women who took another type of
“That sounds very alarming, but we don’t really know if it is clinically
meaningful, and we cannot definitively say that the SSRI use was the reason for
the bone loss,” Diem says. “These are preliminary findings which need to be
SSRIs antidepressants include Prozac, Paxil, Lexapro, and Zoloft.
Antidepressants and Bone Loss
The studies, both published in the June 25 issue of the Archives of
Internal Medicine, are not the first to suggest a link between SSRI
antidepressant use and bone weakening.
In one of the strongest, reported in January, researchers in Canada found
SSRI use to be associated with a twofold increase in the risk of fractures
related to bone loss.
SSRIs work by blocking the protein associated with the movement of
serotonin, the brain chemical linked to depression. The protein has also
recently been discovered in bone, and laboratory studies suggest that SSRIs may
inhibit the functioning of cells associated with bone health.
Diem and colleagues from the University of Minnesota studied SSRI use and
bone loss in a group of 2,722 older women (average age about 78) enrolled in an
Roughly 200 of the women (7.3%) were SSRI users, while 118 (4.3%) took
tricyclic antidepressants, and 2,406 (88%) took neither antidepressant.
Over an average follow up of five years, the SSRI users were found to have
higher rates of hip bone loss than women who took tricyclic antidepressants and
those who did not take antidepressants.
The findings were similar in a study of close to 6,000 men 65 and older.
The men in the study who took SSRIs had lower bone density in the hip and
lower spine than men who took no antidepressants. There were no significant
differences between those who took tricyclic antidepressants and men who took
“SSRIs benefit a lot of people, and no one should stop taking these
medications based on these results,” Diem says. “But it is clear that this
needs to be looked at further.”
Bone Loss Studies in New SSRIs
Osteoporosis researcher Kenneth Saag, MD, tells WebMD that drug companies
developing new SSRI medications should be required to study their drug’s impact
on bone health.
Because depression itself is associated with an increased risk for bone loss
in older people, a better understanding of the impact of antidepressants on
bone is urgently needed, he says.
“The best chance of doing this is for the FDA to encourage, or require, drug
companies to collect this information in future trials,” he says.
In an editorial accompanying the two studies, Saag noted that the benefits
of SSRIs are likely to outweigh the risks for many older people suffering from
“Although it is not appealing to use a second medicine to ‘chase’ the
adverse effects of a first one, if needed, there are many good options that
exist to prevent bone loss,” he writes.