Johann Morelle1, Céline Marechal1, Zanzhe Yu1, Huguette Debaix1, Tanguy Corre1, Mark Lambie1, Marion Verduijn1, Friedo Dekker1, Philippe Bovy1, Pieter Evenepoel1, Bert Bammens1, Rafael Selgas1, Maria A Bajo1, Annemieke M Coester1, Amadou Sow1, Nicolas Hautem1, Dirk G Struijk1, Raymond T Krediet1, Jean-Luc Balligand1, Eric Goffin1, Ralph Crott1, Pierre Ripoche1, Simon Davies1, Olivier Devuyst1. 1. From the Division of Nephrology, Cliniques Universitaires Saint-Luc (J.M., E.G., O.D.), and Institut de Recherche Expérimentale et Clinique (J.M., C.M., H.D., A.S., N.H., J.-L.B., E.G., O.D.) and Institut de Recherche Santé et Société, Faculty of Public Health (R.C.), UCLouvain, Brussels, the Division of Nephrology, Clinique Saint-Joseph, Liege (P.B.), and the Department of Microbiology, Immunology, and Transplantation, Nephrology and Renal Transplantation Research Group, KU Leuven (P.E., B.B.), and the Department of Nephrology, Dialysis, and Renal Transplantation, University Hospitals Leuven (P.E., B.B.), Leuven - all in Belgium; the Department of Nephrology, Shanghai Jiao Tong University School of Medicine and Renji Hospital, Shanghai, China (Z.Y.); the Faculty of Medicine and Health Sciences, Keele University, Keele, United Kingdom (Z.Y., M.L., S.D.); the Institute of Physiology, University of Zurich, Zurich (H.D., O.D.), and the Center for Primary Care and Public Health (Unisanté), University of Lausanne, Lausanne (T.C.) - both in Switzerland; the Department of Clinical Epidemiology, Leiden University Medical Center, Leiden (M.V., F.D.), the Division of Nephrology, Department of Medicine, Amsterdam University Medical Center, University of Amsterdam, Amsterdam (A.M.C., D.G.S., R.T.K.), and the Department of Surgery, University Medical Center Groningen, Groningen (A.M.C.) - all in the Netherlands; the Division of Nephrology, Hospital Universitario La Paz, and Instituto de Investigación Sanitaria La Paz, Red de Investigación Renal, Universidad Autonoma, Madrid (R.S., M.A.B.); and Institut National de la Transfusion Sanguine, Paris (P.R.).
Abstract
BACKGROUND: Variability in ultrafiltration influences prescriptions and outcomes in patients with kidney failure who are treated with peritoneal dialysis. Variants in AQP1, the gene that encodes the archetypal water channel aquaporin-1, may contribute to that variability. METHODS: We gathered clinical and genetic data from 1851 patients treated with peritoneal dialysis in seven cohorts to determine whether AQP1 variants were associated with peritoneal ultrafiltration and with a risk of the composite of death or technique failure (i.e., transfer to hemodialysis). We performed studies in cells, mouse models, and samples obtained from humans to characterize an AQP1 variant and investigate mitigation strategies. RESULTS: The common AQP1 promoter variant rs2075574 was associated with peritoneal ultrafiltration. Carriers of the TT genotype at rs2075574 (10 to 16% of patients) had a lower mean (±SD) net ultrafiltration level than carriers of the CC genotype (35 to 47% of patients), both in the discovery phase (506±237 ml vs. 626±283 ml, P = 0.007) and in the validation phase (368±603 ml vs. 563±641 ml, P = 0.003). After a mean follow-up of 944 days, 139 of 898 patients (15%) had died and 280 (31%) had been transferred to hemodialysis. TT carriers had a higher risk of the composite of death or technique failure than CC carriers (adjusted hazard ratio, 1.70; 95% confidence interval [CI], 1.24 to 2.33; P = 0.001), as well as a higher risk of death from any cause (24% vs. 15%, P = 0.03). In mechanistic studies, the rs2075574 risk variant was associated with decreases in AQP1 promoter activity, aquaporin-1 expression, and glucose-driven osmotic water transport. The use of a colloid osmotic agent mitigated the effects of the risk variant. CONCLUSIONS: A common variant in AQP1 was associated with decreased ultrafiltration and an increased risk of death or technique failure among patients treated with peritoneal dialysis. (Funded by the Swiss National Science Foundation and others.).
BACKGROUND: Variability in ultrafiltration influences prescriptions and outcomes in patients with kidney failure who are treated with peritoneal dialysis. Variants in AQP1, the gene that encodes the archetypal water channel aquaporin-1, may contribute to that variability. METHODS: We gathered clinical and genetic data from 1851 patients treated with peritoneal dialysis in seven cohorts to determine whether AQP1 variants were associated with peritoneal ultrafiltration and with a risk of the composite of death or technique failure (i.e., transfer to hemodialysis). We performed studies in cells, mouse models, and samples obtained from humans to characterize an AQP1 variant and investigate mitigation strategies. RESULTS: The common AQP1 promoter variant rs2075574 was associated with peritoneal ultrafiltration. Carriers of the TT genotype at rs2075574 (10 to 16% of patients) had a lower mean (±SD) net ultrafiltration level than carriers of the CC genotype (35 to 47% of patients), both in the discovery phase (506±237 ml vs. 626±283 ml, P = 0.007) and in the validation phase (368±603 ml vs. 563±641 ml, P = 0.003). After a mean follow-up of 944 days, 139 of 898 patients (15%) had died and 280 (31%) had been transferred to hemodialysis. TT carriers had a higher risk of the composite of death or technique failure than CC carriers (adjusted hazard ratio, 1.70; 95% confidence interval [CI], 1.24 to 2.33; P = 0.001), as well as a higher risk of death from any cause (24% vs. 15%, P = 0.03). In mechanistic studies, the rs2075574 risk variant was associated with decreases in AQP1 promoter activity, aquaporin-1 expression, and glucose-driven osmotic water transport. The use of a colloid osmotic agent mitigated the effects of the risk variant. CONCLUSIONS: A common variant in AQP1 was associated with decreased ultrafiltration and an increased risk of death or technique failure among patients treated with peritoneal dialysis. (Funded by the Swiss National Science Foundation and others.).
Authors: Juan Manuel Sacnun; Robin Hoogenboom; Fabian Eibensteiner; Isabel J Sobieszek; Markus Unterwurzacher; Anja Wagner; Rebecca Herzog; Klaus Kratochwill Journal: Int J Mol Sci Date: 2022-07-20 Impact factor: 6.208