Associations of sodium and potassium intake with chronic kidney disease in a prospective cohort study: findings from the Hispanic Community Health Study/Study of Latinos, 2008-2017

Abstract

Background: According to dietary recommendations, reduction of sodium intake has potential to reduce Chronic Kidney Disease (CKD) risk; however the role of dietary potassium and the sodium -to- potassium ratio in the development of CKD is unclear.

Methods: We studied 9778 participants of the Hispanic Community Health Study/Study of Latinos (HCHS/SOL) from four US urban communities. Participants were aged 18-74 yrs., free from CKD at baseline in 2008-2011 and re-examined between 2014 and - 2017. Dietary intake of sodium, potassium and the ratio of dietary sodium -to- potassium were measured from two baseline 24-h dietary recalls. Incident CKD was defined as: 1) estimated glomerular filtration rate (eGFR) decline of 1 unit per year and eGFR < 60 ml/min/1.73m² or 2) albumin to creatinine ratio ≥ 30 mg/g at the follow-up visit. We used multivariable survey weighted Poisson regression to estimate adjusted incident rates of incident CKD.

Results: At baseline, mean age was 41 years. Average follow up time was 6.2 years. From fully adjusted Poisson regression analyses, self-reported sodium intake was not associated with incident CKD. However, for each 500 mg decrement in potassium intake, there was an 11% increase risk of incident CKD (IRR = 1.11, 95% CI = 1.00, 1.24). Additionally, every 1 M ratio increment of sodium -to -potassium ratio was associated with a 21% increased risk of incident CKD (IRR = 1.21, 95% CI = 1.02, 1.45), p < 0.05).

Conclusions: We conclude that diets low in potassium and high in sodium are associated with increased risk of developing chronic kidney disease among healthy US Hispanic/Latino adults.

Keywords: Chronic kidney disease; Cohort study; Epidemiology; Potassium; Sodium.

Fig. 1

Age and sex adjusted incidence of chronic kidney disease^ǂ by tertile of sodium and potassium intake, The Hispanic Community Health Study/Study of Latinos, 2008–2017. ^ǂIncident chronic kidney disease is defined as eGFR < 60 ml/min/1.73 m2 and/or albumin to creatinine ratio ≥ 30 mg/g. PY refers to person years. *Rate significantly different than reference group p < 0.05

Fig. 2

Incidence Density Ratios of chronic kidney disease^ǂ by sodium and potassium intake, stratified by diabetes status at baseline: The Hispanic Community Health Study/Study of Latinos, 2008–2017. ^ǂIncident chronic kidney disease is defined as eGFR < 60 ml/min/1.73 m2 and/or albumin to creatinine ratio ≥ 30 mg/g. *Incidence Densiity Ratio significant at p < 0.05. **P value for interaction < 0.10. ***All models are adjusted for: age, sex, time between visits, Hispanic/Latino heritage group, education, income, marital status, nativity/years in the US, health insurance, study site, smoking, drinking, physical activity, body mass index, systolic blood pressure, hypertension medication, and total cholesterol. The sodium model is additionally adjusted for potassium intake and the potassium model is additionally adjusted for sodium intake