Marketing Blues for SSRIs?

July 3, 2007

Pharmaceutical Executive

Volume 0, Issue 0

Blockbuster antidepressants linked to bone loss in seniors

Physicians may have to rethink prescribing SSRIs to their patients who are over the age of 50.

Three studies appearing in the Archives of Internal Medicine suggest a link between the use of selective serotonin reuptake inhibitors--including Prozac, Paxil, Lexapro, and Zoloft--and an increase in fractures in both men and women over 50.

"Because depression itself is associated with an increased risk for boneloss in older people, a better understanding of the impact ofantidepressants on bone is urgently needed," wrote Kenneth Saag in "Mind the Mind, but Mind the Bones!" in the June 25 issue of journal. The report alsonoted that depression affects as many as 40 percent of adults over 55.Saag's concern regarding prescribing SSRIs was echoed by a second reportnoting that the use of SSRIs was associated with an increased rate of boneloss in the hip in women (average age at onset was 78.5). This same studynoted that bone loss did not occur with the use of TCAs, or tricyclics, anolder class of antidepressants.

But there's a catch. Unfortunately, simply switching patients to TCAs maynot be the answer.

"Because of concerns about the arrhythmogenic potential of TCAs, there is a strong preference for SSRIs in older adults in whom depression commonlycoincides with heart disease," Saag writes.

To add to the confusion, the mechanism behind SSRIs and bone loss has not been clearly identified. Recent studies have shown a direct link betweencalcium consumption and bone formation in pre-adolescents, which begs thequestion of whether younger patients taking SSRI have an increased lifetimerisk for bone loss.

Manufacturers of SSRIs will no doubt consider this dilemma and the economic fallout from this research.

"While Lilly supports efforts to learn more about this class of medications, due to the inherent, uncontrolled variables between the SSRI user and non-user groups, a causal relationship cannot be established between SSRI use and bone loss," said Charles McAtee, spokesman for Eli Lilly.

"The current Prozac product label lists 'osteoporosis' as an adverse eventoccurring on a rare basis--less than 1 in 10,000 patients, based upon datafrom clinical trials. Decisions concerning the potential risk vs. benefit ofusing any medication should be made with the advice of a physician who iswell-informed about the patient's medical history. As a side note, manystudies show that osteoporosis and depression often coexist," McAtee added.