Predictors of vertebral fractures in patients with severe osteoporosis: a sub-analysis of the Japanese Osteoporosis Intervention Trial-05 (JOINT-05).

UNLABELLED: Incident vertebral fractures are a major issue in elderly women with severe osteoporosis. Beyond well-established risk factors, osteoporosis treatment given, low serum triglyceride levels, and intensity of low back pain were identified as predictors of new fractures in high-risk elderly women. Clinical strategies need to take these findings into account.

PURPOSE: Vertebral fractures (VFs) are a major cause of morbidity and economic burden in aging populations. Despite effective osteoporosis treatments, VF incidence continues to increase. This study aimed to identify predictors for incident VFs in elderly women with severe osteoporosis.

METHODS

This was a post hoc analysis of data of 778 women aged ≥ 75 years with severe osteoporosis from the JOINT-05 trial. We investigated potential predictors for incident VFs, including the burden of prevalent vertebral fractures (number and Genant grade), prior osteoporosis treatment, lipid profile (e.g., triglycerides), low back pain VAS, physical function (timed-up-and-go, one-leg standing), and nutritional indices (e.g., albumin, selected nutrients from the Food Frequency Questionnaire). Multivariate Poisson regression analysis was used to identify independent predictors.

RESULTS

During the study, 138 participants (17.7%) developed incident VFs. The allocated osteoporosis treatment, the number and grade of pre-existing VFs, prior history of osteoporosis treatment, lower serum triglyceride levels, and the low back pain score were significant predictors of incident VFs. VF incidence was significantly higher in patients with pre-existing VFs, although risk did not increase with the severity of existing VFs.

CONCLUSION

Beyond established risk factors such as pre-existing fractures, this study identified the allocation of osteoporosis treatment, low serum triglyceride levels, and the intensity of low back pain as independent predictors of new VFs in high-risk elderly women. Thus, clinical strategies to prevent subsequent fractures should include optimizing pharmacological treatment (e.g., sequential therapy with teriparatide), considering lipid status, and implementing effective, multimodal pain management.