title: Higher protein intake is associated with increased risk for incident end-stage renal disease among blacks with diabetes in the Southern Community Cohort Study.
abstract: Diabetes, a risk factor for end-stage renal disease (ESRD), is associated with impaired protein metabolism. We investigated whether protein intake is associated with ESRD and whether the risk is higher among blacks with diabetes.
  
  
  
  We conducted a nested case-control study of ESRD within the Southern Community Cohort Study, a prospective study of low-income blacks and whites in the southeastern US (2002-2009). Through 2012, 1057 incident ESRD cases were identified by linkage with the United States Renal Data System and matched to 3198 controls by age, sex, and race. Dietary intakes were assessed from a validated food frequency questionnaire at baseline. Odds ratios (ORs) and 95% confidence intervals (CIs) were computed from logistic regression models that included matching variables, BMI, education, income, hypertension, total energy intake, and percent energy from saturated and polyunsaturated fatty acids. Mean (±SD) daily energy intake from protein was higher among ESRD cases than controls (15.7 ± 3.3 vs. 15.1 ± 3.1%, P < 0.0001). For a 1% increase in percent energy intake from protein, the adjusted ORs (95% CIs) for ESRD were 1.06 (1.02-1.10) for blacks with diabetes, 1.02 (0.98-1.06) for blacks without diabetes, 0.99 (0.90-1.09) for whites with diabetes and 0.94 (0.84-1.06) for whites without diabetes. Protein intake in g/kg/day was also associated with ESRD (4th vs. 1st quartile OR = 1.76; 95% CI: 1.17-2.65).
  
  
  
  Our results raise the possibility that among blacks with diabetes, increased dietary protein is associated with increased incidence of ESRD. Studies on how protein intake and metabolism affect ESRD are needed.
authors: Division of Nephrology and Hypertension, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Vanderbilt Center for Kidney Disease, Nashville, TN 37232, USA.
authors: R
authors: R
authors: Malhotra
authors: Division of Nephrology and Hypertension, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Vanderbilt Center for Kidney Disease, Nashville, TN 37232, USA.
authors: K L
authors: KL
authors: Cavanaugh
authors: Division of Epidemiology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37203, USA; International Epidemiology Institute, Rockville, MD 20850, USA.
authors: W J
authors: WJ
authors: Blot
authors: Division of Nephrology and Hypertension, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Vanderbilt Center for Kidney Disease, Nashville, TN 37232, USA.
authors: T A
authors: TA
authors: Ikizler
authors: Vanderbilt Center for Kidney Disease, Nashville, TN 37232, USA; Division of Epidemiology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37203, USA.
authors: L
authors: L
authors: Lipworth
authors: Vanderbilt Center for Kidney Disease, Nashville, TN 37232, USA; Division of Epidemiology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN 37203, USA. Electronic address: edmond.kabagambe@vanderbilt.edu.
authors: E K
authors: EK
authors: Kabagambe
mesh_terms: D000328:Adult; D001741:Black or African American; D000368:Aged; D016022:Case-Control Studies; D016208:Databases, Factual; D003928:Diabetic Nephropathies / Q000175:diagnosis / Q000208:ethnology*; D004044:Dietary Proteins / Q000009:adverse effects*; D002149:Energy Intake / Q000208:ethnology; D005247:Feeding Behavior / Q000208:ethnology; D005260:Female; D054624:Health Status Disparities; D006801:Humans; D015994:Incidence; D007676:Kidney Failure, Chronic / Q000175:diagnosis / Q000208:ethnology*; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D011446:Prospective Studies; D064167:Recommended Dietary Allowances; D018570:Risk Assessment; D012307:Risk Factors; D011795:Surveys and Questionnaires; D013997:Time Factors; D014481:United States / Q000453:epidemiology; D044465:White People
chemical_list: D004044:Dietary Proteins
keywords: Blacks; Cohort; Diabetes; ESRD; Protein; Renal disease