Consumption of nitrate containing vegetables and the risk of chronic kidney disease: Tehran Lipid and Glucose Study

Ren Fail. 2016 Jul;38(6):937-44. doi: 10.3109/0886022X.2016.1165118. Epub 2016 Apr 7.

Abstract

Background: There is growing evidence regarding the potential properties of nitrate-rich foods in development of chronic diseases. In this study, we investigated the association of nitrate-containing vegetables (NCVs) and the risk of chronic kidney disease (CKD).

Methods: We evaluated 1546 eligible adult participants of the Tehran Lipid and Glucose Study (TLGS), at baseline (2006-2008) and again after 3 years (2009-2011). Dietary intake was collected using the validated semi-quantitative food frequency questionnaire. Nitrate-containing vegetables and its categories including high-, medium-, and low-nitrate vegetables were defined. Estimated glomerular filtration rate (eGFR) and CKD were defined. Association between NCVs and CKD in the cross-sectional phase and the predictability of NCVs consumption in CKD occurrence were assessed using multivariable logistic regression models with adjustment for potential confounders.

Results: Mean dietary intake of energy-adjusted NCVs was 298.0 ± 177.3 g/day. Highest compared to the lowest tertile of NCVs was accompanied with a significantly lower mean eGFR (76.6 vs. 83.3, mL/min/1.73 m(2), p < 0.001) and a higher prevalence of CKD (21.7 vs. 9.9%, p < 0.001). At baseline, higher intake of high-NCVs was associated with a 48% higher chance of having CKD (OR = 1.48, 95% CI = 1.05-2.13). After 3 years of follow-up, there was no significant association between consumption of total NCVs and its categories with the occurrence of CKD.

Conclusion: Considering the lack of association between high-NCVs intakes and the risk of CKD in prospective analysis, additional research is recommended to clarify possible effect of nitrate intakes from vegetables on kidney function.

Keywords: Chronic kidney diseases; fruits and vegetables; nitrate.

MeSH terms

  • Adult
  • Cross-Sectional Studies
  • Diet*
  • Female
  • Glomerular Filtration Rate
  • Humans
  • Iran / epidemiology
  • Linear Models
  • Logistic Models
  • Male
  • Middle Aged
  • Multivariate Analysis
  • Nitrates / adverse effects
  • Nitrates / analysis*
  • Prospective Studies
  • Renal Insufficiency, Chronic / epidemiology*
  • Risk Factors
  • Vegetables*

Substances

  • Nitrates