Bone Abstracts

Introduction: The reported prevalence of secondary causes for osteoporosis in men and women aged ≥50 years with a fracture is 35–60%, but data on these causes are scarce in patients with osteopenia and fractures.

Objective: To investigate whether secondary causes for osteoporosis are prevalent and may contribute to fracture risk in patients aged ≥50 years with osteopenia and a recent fracture.

Materials and methods: Consecutive patients of both genders aged≥ 50 years presenting with a recent fracture over an 18-month period, and who had osteopenia, were evaluated using FRAX and laboratory investigations for screening for secondary causes for osteoporosis. Patients with a fracture and osteoporosis were used as controls.

Results: Of 553 patients presenting with a fracture, 30% had osteoporosis and 56% osteopenia. In this latter group median age was 66 years, male:female ratio was 1:3 and 76% had greater than or equal to one identifiable secondary cause for osteoporosis compared to 81% of patients with osteoporosis. Mean FRAX score was 10%/3% and captured 48% of secondary causes for osteoporosis: smoking (16%), excessive alcohol use (14%), corticosteroid use (13%), rheumatoid arthritis (2%) and other secondary causes including insulin dependent diabetes, hyperthyroidism, hypogonadism and early menopause (20%). On additional laboratory investigations 45% had serum-25OHD <50 nmol/l, 11% impaired renal function (eGFR<60 ml/min), 10% monoclonal gammopathy, and 2 and 6% primary and secondary hyperparathyroidism, respectively. There was no difference in prevalence of secondary causes for osteoporosis between patients with osteopenia and osteoporosis. There was a significant relationship between number of secondary causes for osteoporosis and mean BMD at the femoral neck. In patients with osteopenia, 54% of secondary causes were identified by laboratory investigations, 32% were amenable to lifestyle changes and 39% were treatable.

Conclusion: Our findings suggest a high prevalence of potentially reversible secondary causes for osteoporosis which may contribute to fracture risk by altering bone quality in patients with osteopenia and a recent fracture.