Prevalence of Obstructive Sleep Apnoea in Chronic Kidney Disease Patients and Its Co-Relation with Disease Progression. A Prospective Interventional Study
Introduction: Sleep Apnoea is one of the important co-morbidities associated with CKD patients.Patients with end stage renal disease(ESRD) have an increased prevalence of OSA.Sleepapnoea occurs in atleast 50% to 60% of CKD patients with ESRD and the prevalence of sleep apnoea in CKD patients is 10 times higher than the general population.
Materials and Methods: A detailed history and examination was carried out for each CKD subject who entered in the study.Polysomnography was done and patients were thoroughly investigated for OSA.Subject who were diagnosed as a case of OSA were followed up for the period of six months.Cases were made to apply CPAP machine daily during night and their monthly renal function test and eGFR was monitored for 6 months.
Inclusion criteria- All CKD patients giving consent for the study
Exclusion criteria- Age<18 yearsNon-Diagnostic nocturnal PolysomnographyPatients with prior treatment with CPAP or use of home oxygen therapyPatients who had severe acute complication such as acute coronary syndrome, stroke, Acute Heart Failure
Out of total 70 CKD cases 45 were selected for Polysomnography(level-1).TheireGFR was calculated using the Chronic kidney disease epidemiology collaboration(CKD-EPI)equation.Diagnosed cases of CKD with eGFR<=90ml/min/1.73m2 were included in the study.Out of 45 cases follow up by daily CPAP application was completed for only 7 cases after 6 months.Their monthly AHI and eGFR was calculated and effect of regular CPAP application on severity of OSA and declining eGFR was seen.
Data was analysed using SPSS21.Significance of relation between OSA and eGFR made through ANOVA statistical method. P value of <0.05 was considered significant. Linear regression was applied for follow up of AHI and eGFR.
• Prevalence of OSA in CKD patients was found to be 64%
• We found that severity of AHI increases with decrease in eGFR, it was statistically significant(F value=57.003,p=<0.001) and Respiratory disturbance index increases with decrease in eGFR(F value=47.844,p value=<0.001)
• If there is 1 unit increment of time there is decrement of 0.091 unit in eGFR and 0.166 unit decrement of AHI.These data were statistically significant with p value of 0.004 for both.
• Prevalence of OSA is much higher in CKD population than general population.
• Increasing OSA severity is associated with decreasing eGFR.
• CPAP application is associated with decreasing OSA severity and symptoms.
• CPAP does not have any renoprotective effect on declining eGFR.
Keywords - Obstructive Sleep Apnea, Chronic Kidney Disease, AHI