Sleep apnea in patients with chronic kidney disease: a single center experience

PURPOSE: The primary objective of this cross-sectional study was to test factors associated with sleep apnea in patients with chronic kidney disease (CKD). The prevalence of sleep apnea was also assessed. METHODS: We recruited patients with CKD Stage 3-5 who lived in the St. John's area from September 2012 to December 2012. The Berlin Questionnaire and Short Form 36 Quality of Life Health Survey Questions (SF-36) were administered to all participants. RESULTS: We recruited 303 patients (41% female). A total of 157 (51.8%) patients had a high risk for sleep apnea. Higher body mass index and young age were correlated with sleep apnea. Physical component score of SF-36 (PCS) tested as a continuous variable indicated a significant association with the risk for sleep apnea (OR: 0.97, 95% CI: 0.94-0.99, p = 0.03). The association implies 3% change per one point increase in PCS. We categorized mental component score of SF-36 (MCS) into four quartiles, as the linearity assumption was violated. There was a 61% risk increase for poor sleep in those with an MCS score less than the 75th percentile, when compared to those above the 75th percentile (OR: 0.39, 95% CI: 0.21-0.71, p = 0.002). CONCLUSIONS: Sleep apnea is common in kidney patients. People who have low PCS and MCS scores are more prone to sleep apnea or vice versa. Our results also indicate that high BMI and young age are associated with sleep apnea.