Obstructive sleep apnea in non-dialysis chronic kidney disease patients.

There is an enormous increase in the burden of chronic kidney disease both in developing and developed countries. There is a paucity of data on obstructive sleep apnea (OSA) in chronic kidney disease (CKD) patients in India. We used a cross-sectional prospective observational study to determine the prevalence of OSA in non-dialysis CKD patients. Of the 647 CKD patients 302 patients were in stage II, III and IV. The study population was screened using the Berlin questionnaire and 87 patients were positive for OSA (28%). Among the 87, 37 patients were excluded based on the exclusion criteria. Fifty patients underwent a split night sleep study. Stage II, III CKD patients were clubbed as early CKD or group one and stage IV CKD patients were clubbed as late CKD or group two. The spilt night study revealed an 88% incidence of OSA of varying severity. A sub group analysis was done to assess the severity of OSA. A statistical significance (p<0.05) between early and late CKD group was observed with respect to AHI and ODI. An improvement in the late CKD is observed and the Z values for AHI and ODI are 4.273 and 2.307, respectively. The prevalence and incidence of OSA was found to be 28% and 88% in non-dialysis CKD patients, respectively and the risk and severity of OSA increased with the progression of CKD stages and thus necessitating the need for screening the non-dialysis CKD population.