Bone mineral density in patients with obstructive sleep apnea syndrome

Obstructive sleep apnea syndrome (OSAS) is a disorder that is characterized by repetitive pauses in breathing during sleep. Airway obstruction episodes can lead to ischemia or hypoxia in tissues. Hypoxia may also have an effect on bone metabolism. In this study, we aim to investigate both the bone metabolic abnormalities and bone mineral density (BMD) in OSAS patients compared to individuals without OSAS.

Twenty-one male patients with OSAS and 26 control subjects, also male, enrolled in this study. Serum calcium, phosphorus, alkaline phosphatase, and urinary desoxypiridinoline levels were measured in all participants, and BMD was evaluated using DEXA (Hologic QDR 2000). The BMD was measured in the lumbar spine (L1-L4), the femoral neck, and total femur region.

No statistically significant difference was noted between the two groups with respect to demographic data, except for body mass index (BMI). We adjusted the statistical analyses in line with the BMI and noted significant differences between OSAS patients and control subjects with regard to lumbar L1-L4 t score, lumbar L1-L4 BMD, and femoral neck BMD values (p ≤ 0.001). We find significant correlations with lumbar L1-L4 BMD (r = -0.4; p = 0.023) and lumbar L1-L4 t score values (r = -0.5; p = 0.012).

Our study indicates that there is a relationship between OSAS and osteoporosis. However, further controlled studies comprising a greater number of patients are needed to investigate the relationship between osteoporosis and OSAS.