Global perspectives on the burden and management of hypophosphataemic osteomalacia in adult patients: an International Osteoporosis Foundation (IOF) survey

Abstract

Summary

This survey collected global perspectives on the burden and management of hypophosphataemic osteomalacia in adults through the International Osteoporosis Foundation (IOF). The IOF network represents a valuable international resource for understanding the burden and management of rare bone disorders.

Purpose

To investigate the international burden and management of hypophosphataemic osteomalacia (HO) in adult patients.

Methods

A survey was developed consisting of seven questions about respondents and their experiences of managing HO, with a second section inviting additional non-identifying information on up to five patients. The survey was disseminated to the International Osteoporosis Foundation (IOF) network.

Results

Forty clinicians from 24 countries responded, with most based in academic centres. Respondents reported managing over 1000 adult patients with HO, primarily diagnosed with X-linked hypophosphataemia (XLH; 35%), tumour-induced osteomalacia (TIO; 24%), and fibrous dysplasia/McCune–Albright syndrome (FD/MAS; 16%). Management varied by diagnosis, reflecting differences in the underlying pathophysiology and clinical manifestations of the disorders. Respondents provided additional information on 19 patients with XLH, 28 with TIO, and 9 with other HO disorders. Common symptoms across XLH and TIO included bone pain (XLH, 67%; TIO, 88%), muscle pain (XLH, 61%; TIO, 76%), and muscle weakness (XLH, 61%; TIO, 88%). Many patients with XLH had discontinued phosphate and vitamin D therapies, with a subset initiating burosumab treatment. In contrast, phosphate and vitamin D were commonly used in TIO, with many patients being considered for tumour resection and limited burosumab use. Pain medication use, including opiates, was relatively high across all patients.

Conclusion

Adults with HO experience a significant burden of musculoskeletal symptoms. Future efforts should focus on global education of healthcare professionals. The IOF network represents a valuable international resource for understanding the burden and management of rare bone disorders.