Abstract
BACKGROUND: High-potassium intake is associated with a lower risk of cardiovascular disease. However, the association between potassium intake and the development of chronic kidney disease (CKD) remains unclear.
OBJECTIVE: The objective of this study was to investigate whether potassium intake is associated with outcomes of incident CKD.
METHODS: This is a population-based prospective observational cohort study from the UK Biobank cohort between 2006 and 2010. We included 317,162 participants without CKD from the UK Biobank cohort. The main predictor was spot urine potassium-to-creatinine ratio (KCR). The primary outcome was incident CKD, which was defined by the International Classification of Disease 10 codes or Operating Procedure Codes Supplement 4 codes.
RESULTS: At baseline, individuals with higher KCR had lower blood pressure, body mass index, and inflammation, and were less likely to have diabetes and hypertension. During a median follow-up of 11.9 y, primary outcome events occurred in 15,246 (4.8%) participants. In the cause-specific model, the adjusted hazard ratio (aHR) per 1-standard deviation increase in KCR for incident CKD was 0.90 [95% confidence interval (CI): 0.89, 0.92]. Compared with quartile 1 of KCR, the aHRs (95% CIs) for quartiles 2-4 were 0.98 (0.94, 1.02), 0.90 (0.86, 0.95), and 0.80 (0.76, 0.84), respectively. In sensitivity analysis with different definitions of CKD, the results were similar. In addition, further analysis with dietary potassium intake also showed a negatively graded association with the primary outcome.
CONCLUSIONS: Higher urinary potassium excretion and intake were associated with a lower risk of incident CKD.