Circulating serotonin and bone turnover markers are not correlated with a prevalent fragility fracture and menopausal osteopenia at central dual-energy x-ray absorptiometry

Depression and anti-depressants as well as obesity may enhance the risk of an osteoporotic fracture by targeting, among others, serotonin pathways despite the fact that the bone mineral density at central Dual-Energy X-Ray Absorptiometry (DXA) is relatively high.
We introduce such a case on a menopausal female. A 57-year old woman had total thyroidectomy for multi-nodular goiter and further thyroid substitution was offered. She entered menopause at 50 years, she was diagnosed and treated for depression during 3 years since the age of 53. At 56 years she suffered a left elbow fracture consistent with osteoporotic fracture.
Central DXA showed osteopenia. She also suffered of grade 2 obesity and relatively low vitamin D. The bone remodelling markers were within normal limits. We tested circulating serotonin (or 5-hydroxytriptamine using an ELISA kit) at the level of 280 ng mL (Normal between 80 and 450 ng mL). Oral risendronate and vitamin D was started with a good response after first year with the indication of continuing at least two more years.
Circulating serotonin, as well as bone turnover markers, may play a role on osteoporotic fractures but not in each case; similarly, a low-trauma fracture is not perfectly reflected on bone mineral density at central DXA.