Bone Mineral Density in Sheehan's Syndrome; Prevalence of Low Bone Mass and Associated Factors

Hypopituitarism is a known cause of bone mineral loss. This study aimed to evaluate the frequency of osteopenia and osteoporosis in patients with Sheehan's syndrome (SS) and to determine the risk factors. This is a retrospective study of 60 cases of SS that have had a bone mineral density (BMD) measurement. Clinical, biological, and therapeutic data were collected. The parameters of osteodensitometry at the femoral neck and the lumbar spine of 60 patients with SS were compared with those of 60 age-, height-, and weight matched control women. The mean age at BMD measurement was 49.4 +/- 9.9 yr (range: 25-76 yr). The mean duration of SS was 19.3 +/- 8.5 yr (range: 3-41 yr). All patients had corticotropin deficiency and were treated with hydrocortisone at a mean daily dose of 26.3 +/- 4.1 mg. Fifty-seven patients (95%) had thyrotropin deficiency and were treated with thyroxine at a mean daily dose of 124.3 +/- 47.4 mu g. Thirty-five of the 49 patients, aged less than 50 yr at diagnosis and having gonadotropin deficiency (71.4%), had estrogen-progesterone substitution. Osteopenia was present in 25 patients (41.7%) and osteoporosis in 21 (35.0%). The BMD was significantly lower in the group with SS than in the control group (p < 0.001). The odds ratio of osteopenia-osteoporosis was 3.1 (95% confidence interval: 1.4-6.8) at the femoral neck and 3.7 (95% confidence interval: 1.7-7.8) at the lumbar spine. The lumbar spine was more frequently affected by low bone mineral mass (p < 0.05). The duration of the disease and the daily dose of hydrocortisone were independently and inversely associated with BMD at the femoral neck. The daily dose of thyroxine was independently and inversely associated with BMD at the lumbar spine. Estrogen-progesterone replacement therapy was not associated with BMD. Low bone mineral mass was very common in patients with SS. The lumbar spine was more frequently affected. The duration of the disease and the doses of hydrocortisone and thyroxine were involved in bone mineral loss.