Depression Connected to Bone Loss

Severe depression can lead to suicide, but milder cases are related not only to mental sufferance: a new National Institute of Mental Health (NIMH) research shows that premenopausal women with mild depression experience increased bone mass loss than their non-depressed counterparts, similar to that induced by smoking, low calcium intake and sedentarism.

Hip bones (top fracture location amongst elders) displayed the highest thinning in depressed premenopausal women. Lower bone mass makes women more prone to costly, even deadly fractures as they age.

"Osteoporosis is a silent disease. Too often, the first symptom a clinician sees is when a patient shows up with a broken bone. Now we know that depression can serve as a red flag - that depressed women are more likely than other women to approach menopause already at higher risk of fractures," said NIMH Deputy Director Dr. Richard Nakamura.

Bone mass is highest in youth and bone mass loss takes place throughout life, speeding up after menopause. The NIMH research strengthens previous observations linking depression to osteoporosis.

The investigation was made of 89 depressed women and 44 nondepressed women, all aged 21 to 45 and premenopausal. Both groups presented the same intake levels of calcium, caffeine, alcohol and oral contraceptives; smoking; physical fitness; and all women had the same age of first menstrual period. Subjects had a relatively high socioeconomic status; the main difference was that depressed women took antidepressant drugs. Older adults taking selective serotonin reuptake inhibitors antidepressants are known to experience increased osteoporosis. But the NIMH research did not connect those drugs with increased osteoporosis in premenopausal women.

17 % of the depressed subjects had increased osteoporosis (bone density was measured through DXA scanning) in the femoral neck (the vulnerable portion of the hip), compared with 2 % in the case of not depressed subjects. Osteoporosis in the lumbar spine (lower back) was detected in 20 % of depressed women, compared to 9 % of nondepressed subjects.
The team did not find a strong connection between the osteoporosis intensity and the level of depression.

"Depression generally isn't on clinicians' radar screens as a major risk factor for osteoporosis, particularly for premenopausal women. It should be," said lead author Dr. Giovanni Cizza of NIMH and the NIH National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK).

Blood and urine analysis revealed that depressed women had imbalances in immune-system substances, compared to their healthy counterparts, pointing towards a connection between depression-induced immune affections and osteoporosis. This could be caused by the high levels of adrenalin in depression, which over-activate the immune system.

The depressed subjects presented higher amounts of immune-system proteins boosting inflammation (like IL-6) and lower amounts of those impeding it. IL-6 had been found to increase bone loss.