Sleep Apnea and Kidney Function Trajectory: Results From a 20-Year Longitudinal Study of Healthy Middle-Aged Adults

Abstract Study Objectives To determine whether sleep apnea, defined by polysomnography, accelerates kidney function decline in generally healthy adults not selected for sleep apnea or kidney disease. Methods We performed a retrospective cohort study in 855 participants from the Wisconsin Sleep Cohort Study, a large 20-year population-based study of sleep apnea, who had at least one polysomnogram and serial measurements of serum creatinine over time. Sleep apnea was defined as an apnea–hypopnea index ≥ 15 or positive airway pressure (PAP) use at baseline. We compared the slope of estimated glomerular filtration rate (eGFR) change and odds of rapid eGFR decline (>2.2 mL/minute/1.73 m2/year) for those with and without sleep apnea. Results The mean follow-up was 13.9 ± 3.4 years. The cohort was 50.4 ± 7.6 years, 55% male, and 97% white. The mean eGFR was 89.3 ± 13.8 mL/minute/1.73 m2 and 11% had sleep apnea. Overall, the mean eGFR change was −0.88 ± 1.12 mL/minute/1.73 m2/year. Compared with those without sleep apnea, participants with sleep apnea had a 0.2 mL/minute/1.73 m2/year slower eGFR decline though this was not statistically significant (95% CI [−0.06–0.45], p = .134). When we excluded those on PAP therapy (n = 17), eGFR decline was even slower among those with sleep apnea (0.36 mL/minute/1.73 m2/year slower, 95% CI [0.08–063], p = .012). Those with sleep apnea had lower odds of rapid eGFR decline but this was not statistically significant, even after excluding PAP users. Conclusion Among healthy middle-aged adults, the presence of sleep apnea at baseline did not accelerate kidney function decline compared with those without sleep apnea over time.