Older women who take certain antidepressants are at increased risk of fracturing a bone, but it's not clear whether the association is due to the drugs, depression itself, or some other factor, according to a report in the Harvard Women's Health Watch.
Nevertheless, while women shouldn't stop takingantidepressant drugs for the sole reason of protecting their bones, those who suffer from depression should get their bone mineral density checked out, the report's authors say.
They cite a study published this January in the Archives of Internal Medicine that found women over 50 who were taking selective serotonin reuptake inhibitors, a class of antidepressant drugs that includes Prozac and Zoloft, were twice as likely to suffer fractures compared with their peers who were not taking them.
However, the researchers add, just 137 of the more than 5000 study participants were on the drugs, and these women were also more likely to be taking other drugs that could contribute to bone loss.
Nevertheless, the Harvard newsletter article authors point out that there have been reports since the 1990s linking depression in women, even younger women in whom thinning bones is relatively rare, to lower bone mineral density. One of these studies found depressed women had higher levels of the stress hormone cortisol, which contributes to bone loss.
Another study in animals found depression boosted secretion of another hormone, noradrenalin, which blocks the activity of bone-forming cells. A number of other substances in the body, including leptin, may also be involved in the mental health-bone strength link, the authors say.
Depressed women simply may not eat as well and exercise as much as their non-depressed peers, both of which can lead to bone loss, the authors add.
Dr Jessica Goren, a clinical psychiatric pharmacist at Cambridge Health Alliance, notes that depressed individuals should be informed and counselled on their osteoporosis risk, "because regardless of whether depression is an independent factor, lifestyle is".
The authors suggest that women who are taking antidepressants discuss the risk of osteoporosis with their doctor and get a bone mineral density test.
