title: A proinflammatory diet is associated with systemic inflammation and reduced kidney function in elderly adults.
abstract: BACKGROUND
  Diet can affect kidney health through its effects on inflammation.
  
  
  OBJECTIVE
  We tested whether the Adapted Dietary Inflammatory Index (ADII) is associated with kidney function and whether effects of diet on chronic low-grade inflammation explain this association.
  
  
  METHODS
  This was an observational analysis in 1942 elderly community-dwelling participants aged 70-71 y from 2 independent cohorts: the Uppsala Longitudinal Study of Adult Men (n = 1097 men) and the Prospective Investigation of Vasculature in Uppsala Seniors (n = 845 men and women). The ADII was calculated from 7-d food records, combining putatively proinflammatory and anti-inflammatory effects of nutrients, vitamins, and trace elements. The ADII was validated against serum C-reactive protein (CRP) concentrations. The estimated glomerular filtration rate (eGFR) was assessed from serum cystatin C (cys) and creatinine (crea). Associations between the ADII and eGFR were investigated, and CRP was considered to be a mediator.
  
  
  RESULTS
  In adjusted analysis, a 1-SD higher ADII was associated with higher CRP (β: 6%; 95% CI: 1%, 10%; P = 0.01) and lower eGFR [Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI)cys: -2.1%; 95% CI: -3.2%, -1.1%; CKD-EPIcys+crea: -1.8%; 95% CI: -2.7%, -0.9%; both P < 0.001]. CRP was also inversely associated with eGFR. Mediation analyses showed that of the total effect of the ADII on kidney function, 15% and 17% (for CKD-EPIcys+crea and CKD-EPIcys equations, respectively) were explained/mediated by serum CRP. Findings were similar when each cohort was analyzed separately.
  
  
  CONCLUSIONS
  A proinflammatory diet was associated with systemic inflammation as well as with reduced kidney function in a combined analysis of 2 community-based cohorts of elderly individuals. Our results also suggest systemic inflammation to be one potential pathway through which this dietary pattern is linked to kidney function.
authors.affiliation: Divisions of Renal Medicine and Baxter Novum, Department of Clinical Science, Intervention, and Technology, and.
authors.forename: Hong
authors.initials: H
authors.lastname: Xu
authors.affiliation: Department of Public Health and Caring Sciences, Clinical Nutrition and Metabolism, and.
authors.forename: Per
authors.initials: P
authors.lastname: Sjögren
authors.affiliation: Department of Medical Sciences, Molecular Epidemiology, Uppsala University, Uppsala, Sweden; School of Health and Social Studies, Dalarna University, Falun, Sweden; and.
authors.forename: Johan
authors.initials: J
authors.lastname: Ärnlöv
authors.affiliation: Division of General Internal Medicine, Department of Medicine, University of California, San Francisco, San Francisco, CA.
authors.forename: Tanushree
authors.initials: T
authors.lastname: Banerjee
authors.affiliation: Department of Public Health and Caring Sciences, Clinical Nutrition and Metabolism, and.
authors.forename: Tommy
authors.initials: T
authors.lastname: Cederholm
authors.affiliation: Department of Public Health and Caring Sciences, Clinical Nutrition and Metabolism, and.
authors.forename: Ulf
authors.initials: U
authors.lastname: Risérus
authors.affiliation: Divisions of Renal Medicine and Baxter Novum, Department of Clinical Science, Intervention, and Technology, and.
authors.forename: Bengt
authors.initials: B
authors.lastname: Lindholm
authors.affiliation: Department of Medical Sciences, Molecular Epidemiology, Uppsala University, Uppsala, Sweden;
authors.forename: Lars
authors.initials: L
authors.lastname: Lind
authors.affiliation: Divisions of Renal Medicine and Baxter Novum, Department of Clinical Science, Intervention, and Technology, and Center for Molecular Medicine, Karolinska Institutet, Stockholm, Sweden; juan.jesus.carrero@ki.se.
authors.forename: Juan Jesús
authors.initials: JJ
authors.lastname: Carrero
mesh_terms: D000368:Aged; D002097:C-Reactive Protein / Q000378:metabolism; D003404:Creatinine / Q000097:blood; D003430:Cross-Sectional Studies; D055316:Cystatin C / Q000097:blood; D004032:Diet; D005260:Female; D005919:Glomerular Filtration Rate; D006801:Humans; D007249:Inflammation / Q000453:epidemiology* / Q000503:physiopathology; D007674:Kidney Diseases / Q000453:epidemiology* / Q000503:physiopathology; D016014:Linear Models; D008137:Longitudinal Studies; D008297:Male; D015999:Multivariate Analysis; D011446:Prospective Studies; D012307:Risk Factors; D013548:Sweden / Q000453:epidemiology; D044465:White People
chemical_list: D055316:Cystatin C; D002097:C-Reactive Protein; D003404:Creatinine
keywords: ADII; CRP; diet; eGFR; inflammation; kidney function