Five-Year Outcomes of Chronic Kidney Disease in a Longitudinal Population-Based Cohort in Western Australia

AIM: To describe 5-year outcomes of chronic kidney disease (CKD) in a large, population-based cohort in Western Australia, including rates of progression, regression, kidney failure and death.

BACKGROUND: CKD is a major public health challenge associated with increased morbidity and mortality, yet the natural history of early-stage disease in population settings remains poorly defined.

METHODS: We conducted a retrospective cohort study using linked pathology and hospital data for adults with incident CKD between 2006 and 2022. CKD stage was defined by two estimated glomerular filtration rate (eGFR) values ≥ 3 and < 12 months apart: mild (45-59), moderate (30-44) and severe (15-29) mL/min/1.73 m 2. Outcomes were assessed over 5 years using a competing risks framework.

RESULTS: Among 153 527 individuals with incident CKD during the study period (mean age 75.6 years, 52.6% women) 118 248 had mild, 58 323 moderate and 20 322 severe CKD. At 5 years, death occurred in 16.8% (mild), 26.7% (moderate) and 30.5% (severe); kidney failure occurred in 0.6%, 2.5% and 30.0%, respectively. CKD progression was more common than regression in mild (20.1% vs. 11.8%) and moderate (18.9% vs. 14.5%) disease. Albuminuria testing was recorded in < 35% of patients.

CONCLUSION: People with early-stage CKD face substantial risks of progression, kidney failure and death within 5 years. The low rate of albuminuria testing suggests missed opportunities for early identification of high-risk individuals and timely intervention. Enhancing CKD detection and monitoring in primary care may improve outcomes.