Are SSRIs bad for the bones?

In the January 22, 2007 issue of the Archives of Internal Medicine, Dr. J.B. Richards et al have written a paper providing evidence that SSRI use is associated with increased falls, increased number of fractures and decrease in bone density measurements in a group of patients age fifty and over.

This was a prospective, multi- institutional study which selected 5008 adults fifty years of age and older and followed them for five years for incident fractures. They found a hazard ratio of 2.1(C.I. 1.3 to 3.4)for fragility fractures. There was a dose effect noted and there is some animal experimental data which provides some degree of biological plausibility.There are functional serotonin receptors in bone and some data suggesting decrease bone mass in mice administered SSRIs.

I have frequently harped about the growing tendency in medical publications to overemphasive the significance of small increases in relative risks or odds ratios (i.e. less than 2). Here we have a fairly credible number for the OR and some biological plausibility but the authors indicate that previous analyses of this possible relationship failed to show an association. So the case is not proven but it is reasonable to consider SSRI use as a possible risk factor in the context of osteoporosis and falls and to have a quicker trigger finger to do BMD measurements and to emphasize the value of adequate amounts of vitamin D and calcium to older patients who take SSRIs.