Continuous Positive Airway Pressure Improves Renal Function in Obese Patients With Obstructive Sleep Apnea Syndrome

Abstract

Background: Obstructive sleep apnea syndrome (OSAS) is an independent risk factor for cardiovascular morbidity and mortality, and it has a detrimental effect on renal function. Obesity is the major risk factor for OSAS, and represents a risk factor for chronic kidney disease. Continuous positive airway pressure (CPAP) is the suggested therapy for moderate-to-severe OSAS. We designed this study to evaluate the effect of CPAP on estimated glomerular filtration rate (e-GFR) in a cohort of obese patients with moderate-to-severe OSAS and normal renal function.Methods: We enrolled 198 obese subjects, divided into two groups (OSAS+ and OSAS–), on the basis of cardiorespiratory monitoring; mild OSAS patients (n = 33) were excluded from the study, thus the analyses were conducted on 165 patients. Comparisons between groups were made by Student t-test or χ2 test as appropriate. Linear regression analyses were used to assess the relationship between baseline e-GFR and different covariates and, in the OSAS+ group, between Δe-GFR and different covariates. A multivariate regression analysis was performed to determinate the independent predictor of the Δe-GFR.Results: OSAS+ subjects showed significantly increased values of systolic blood pressure, HOMA, pulse wave velocity, high-sensitivity C reactive protein and uric acid compared with OSAS– group. OSAS+ group showed significantly lower values of e-GFR and increased values of microalbuminuria. At linear regression analysis e-GFR resulted significantly and inversely related to AHI in the whole study population and in the two groups. After 6 months of CPAP therapy, OSAS+ subjects showed an improvement in respiratory parameters, as well as a significant increase in e-GFR values (104.2 + 19.0 vs. 84.0 + 13.1 ml/min/1.73 m2, P < 0.0001). At multiple regression analysis, Δ apnea/hypopnea index (AHIa) resulted the main independent predictor of Δe-GFR explaining 22% of its variation.Conclusions: Obese OSAS patients show significantly lower values of e-GFR, even if in the normal range, compared with obese non-OSAS subjects. After 6 months of CPAP, e-GFR significantly improved (+20 ml/min/1.73 m2) and ΔAHIa resulted the most important independent predictor of Δe-GFR.

LncR-GAS5 decrease in adenine phosphoribosyltransferase expresssion via binding TAF1 to increase kidney damage created by CIH

“…OSAHS is detrimental to renal function [ 23 ], and renal hypoxia, endothelial dysfunction, and increased oxidative stress have been proposed as possible mechanisms underlying OSAHS-associated renal dysfunction. In our study, sequencing analysis suggested that RNA is deeply involved in the biological process of CIH-mediated kidney injury, TAF1 is significantly increased in the CIH group, APRT is significantly reduced in the CIH group, and inhibition of GAS5 expression or APRT overexpression can attenuate CIH-induced renal injury.…”

Association of sleep characteristics with renal function in menopausal women without recognized chronic kidney disease

“…Sleep disorder can lead to inflammation, oxidative stress, endothelial dysfunction, increased sympathetic tone, activation of the renin-angiotensin system, circadian timing dysfunction and subsequent systemic and intraglomerular pressure, which hereby adversely affects kidney function ( 24 – 26 , 31 , 32 ). Another possible explanation is the impact of sleep disorder on hypertension ( 33 , 34 ), diabetes ( 35 , 36 ), obesity ( 37 ), and metabolic syndrome ( 38 ), which were known to accelerate deterioration of kidney function.…”

Human Hypoxia Models: From Space Medicine to Human Pharmacological Studies

“…However, in severe hypoxia below pO 2 40 mmHg, glomerular filtration rate declines, leading to sodium retention and water retention [95,96]. Hence, renal function in chronic respiratory failure, like OSA or COPD, is often impaired and these patients show fluid and sodium retention [97]. This excess retention has also been described at high altitude, especially in altitude maladapted individuals [98].…”