Dietary acid load and chronic kidney disease among adults in the United States

BMC Nephrol. 2014 Aug 24:15:137. doi: 10.1186/1471-2369-15-137.


Background: Diet can markedly affect acid-base status and it significantly influences chronic kidney disease (CKD) and its progression. The relationship of dietary acid load (DAL) and CKD has not been assessed on a population level. We examined the association of estimated net acid excretion (NAE(es)) with CKD; and socio-demographic and clinical correlates of NAE(es).

Methods: Among 12,293 U.S. adult participants aged >20 years in the National Health and Nutrition Examination Survey 1999-2004, we assessed dietary acid by estimating NAE(es) from nutrient intake and body surface area; kidney damage by albuminuria; and kidney dysfunction by eGFR < 60 ml/min/1.73 m(2) using the MDRD equation. We tested the association of NAE(es) with participant characteristics using median regression; while for albuminuria, eGFR, and stages of CKD we used logistic regression.

Results: Median regression results (β per quintile) indicated that adults aged 40-60 years (β [95% CI] = 3.1 [0.3-5.8]), poverty (β [95% CI] = 7.1 [4.01-10.22]), black race (β [95% CI] = 13.8 [10.8-16.8]), and male sex (β [95% CI] = 3.0 [0.7- 5.2]) were significantly associated with an increasing level of NAE(es). Higher levels of NAE(es) compared with lower levels were associated with greater odds of albuminuria (OR [95% CI] = 1.57 [1.20-2.05]). We observed a trend toward greater NAE(es) being associated with higher risk of low eGFR, which persisted after adjustment for confounders.

Conclusion: Higher NAE(es) is associated with albuminuria and low eGFR, and socio-demographic risk factors for CKD are associated with higher levels of NAE(es). DAL may be an important target for future interventions in populations at high risk for CKD.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Acidosis / diagnosis
  • Acidosis / epidemiology*
  • Acidosis / metabolism*
  • Adult
  • Cross-Sectional Studies
  • Feeding Behavior / physiology*
  • Female
  • Humans
  • Male
  • Middle Aged
  • Nutrition Surveys / methods*
  • Renal Insufficiency, Chronic / diagnosis
  • Renal Insufficiency, Chronic / epidemiology*
  • Renal Insufficiency, Chronic / metabolism*
  • United States / epidemiology