Premenopausal women with major depressive disorder (MDD) have less bone mineral density (BMD) than those without MDD, according to findings of a study published in the November 26 issue of Archives of Internal Medicine. Researchers reported that the level of bone loss in premenopausal women with MDD was at least as high as that associated with recognized risk factors for osteoporosis. The study was funded by the National Institute of Mental Health, the National Institute of Diabetes and Digestive and Kidney Diseases, the National Center for Complementary and Alternative Medicine, and the Warren Magnuson Clinical Center of the NIH.
Lead researchers Giovanni Cizza, MD, PhD, and Farideh Eskandari, MD, and colleagues examined baseline BMD measurements in 89 premenopausal women with MDD and 44 premenopausal women without the disorder aged 21 to 45 years. The study was designed to reduce the possibility that lower bone mass was linked to factors other than depression. Except for MDD, the study participants were similar in risk factors for osteoporosis; smoking; fitness level; use of oral contraceptives; and age of onset of menstruation. One difference between the 2 groups was that 73 women with MDD were taking antidepressant medications, 54 of whom were taking SSRIs.
The team found that the prevalence of low BMD was greater in premenopausal women with MDD than in those in the control group at the femoral neck (17% vs 2%, respectively), total hip (15% vs 2%, respectively), and lumbar spine (20% vs 9%, respectively). There was no significant link between the degree of bone loss and the severity of depression or the number of depressive episodes. According to the researchers, the use of an SSRI did not contribute to low BMD.
Blood and urine samples taken hourly for a full day showed that premenopausal women with MDD had imbalances in immune-system substances, including higher levels of those that produce inflammation, compared with premenopausal women without the disorder. One of these inflammation-producing proteins, IL-6, has been shown to promote bone loss.
