Continuous positive airway pressure treatment improves bone mineral density in men affected by severe obstructive sleep apnea syndrome

Study objectives: Obstructive sleep apnea (OSA) and low bone mineral density (BMD) are two prevalent conditions with a significant negative impact on patients' well-being and quality of life. Recent research consistently showed low BMD at different bone sites in male patients with OSA. Although the efficacy of continuous positive airway pressure (CPAP) treatment for OSA has been widely demonstrated, the evidence for understanding its impact on BMD and other bone-related outcomes is insufficient. The aim of this observational study was to investigate the effect of twelve months of CPAP treatment on lumbar and femur BMD and bone-related serum biomarkers in male patients with severe OSA. Methods: Sixty patients (mean age: 55.1±9.9 years) were consecutively included and underwent BMD measurement with dual-energy x-ray absorptiometry at baseline and after 12 months of CPAP treatment. Vitamin D, parathyroid hormone (PTH), and calcium serum levels were examined at the same time points. Results: Significant increase in BMD in the L1 (p<0.001, d=0.27) and L2 (p<0.001, d=0.26) vertebrae was observed after CPAP treatment, along with an increase in vitamin D (p<0.001, d=0.71) and calcium (p<0.001, d=0.73) levels and a decrease in PTH levels (p<0.001, d=0.60). The increase in BMD in L1 was significantly correlated with the decrease in PTH serum levels (r=-0.50, p<0.001). Conclusions: Overall, these findings showed that beneficial OSA treatment might restore bone health, and support CPAP treatment as a feasible strategy to improve BMD in male patients with severe OSA. Accordingly, diagnosing and targeting OSA may be warranted in the treatment of male patients with undetermined osteopenia and osteoporosis.