CKD Progression and Mortality Among Men and Women: A Nationwide Study in Sweden.

Abstract

RATIONALE AND OBJECTIVE\nChronic kidney disease (CKD) is a global health problem with increasing prevalence. Several sex-specific differences have been reported for disease progression and mortality. Selection and survival bias might have influenced the results of previous cohort studies. Our objective was to investigate sex-specific differences of CKD progression and mortality among patients with CKD not receiving maintenance dialysis.\n\n\nSTUDY DESIGN\nObservational cohort study.\n\n\nSETTING AND PARTICIPANTS\nAdult patients with incident CKD stage G3b-5 identified between 2010 and 2018 within the nationwide Swedish Renal Registry-CKD (SRR-CKD).\n\n\nEXPOSURES\nSex.\n\n\nOUTCOMES\nTime to CKD progression defined as a change of at least one CKD stage or initiation of kidney replacement therapy (KRT), or death. Repeated assessments of eGFR.\n\n\nANALYTICAL APPROACH\nCKD progression and mortality before KRT were assessed by the cumulative incidence function methods and Fine and Gray models with death handled as a competing event. Sex differences in eGFR slope were estimated using mixed effects linear regression models.\n\n\nRESULTS\n7,388 patients with incident stage CKD G3b, 18,282 with incident stage G4 and 9,410 with incident stage G5 were identified. Overall, 19.6 patients/100 patient-years (95 % confidence interval [CI] 19.2-20.0) progressed and 10.1 patients/100 person-years (95 % CI 9.9-10.3) died. Women had a lower risk of CKD progression (subhazard ratio [SHR] 0.88 [0.85-0.92]), and a lower all-cause (SHR 0.90, 95% CI 0.85-0.94) and cardiovascular mortality risk (SHR 0.83, 95% CI 0.76-0.90). Risk factors related to a steeper eGFR slope included age, sex, albuminuria, and type of primary kidney disease.\n\n\nLIMITATIONS\nIncomplete data on outpatient visits and laboratory measurements; regional differences in reporting.\n\n\nCONCLUSIONS\nCompared to women, men had a higher rate of all-cause and cardiovascular mortality, an increased risk of CKD progression, and a steeper decline in eGFR.