title: Risks of diabetic nephropathy with variation in hemoglobin A1c and fasting plasma glucose.
abstract: BACKGROUND
  This study examined whether annual variation in glycosylated hemoglobin A1c (HbA1c) and fasting plasma glucose (FPG), as represented by the coefficient of variation (CV), can predict diabetic nephropathy independently of mean FPG, mean HbA1c, and other risk factors in patients with type 2 diabetes.
  
  
  METHODS
  A computerized database of patients with type 2 diabetes aged ≥30 years and free of diabetic nephropathy (n = 3220) who were enrolled in the Diabetes Care Management Program of China Medical University Hospital before 2007 was used in a time-dependent Cox proportional hazards regression model.
  
  
  RESULTS
  The incidence rates of diabetic nephropathy were 16.11, 22.95, and 28.86 per 1000 person-years in the first, second, and third tertiles of baseline HbA1c-CV, respectively; the corresponding incidence rates for FPG-CV were 9.46, 21.23, and 37.51 per 1000 person-years, respectively. After multivariate adjustment, the corresponding hazard ratios for the second and third tertiles versus the first tertile of annual HbA1c-CV were 1.18 (95% confidence interval [CI], 0.88-1.58) and 1.58 (95% CI, 1.19-2.11), respectively, and 1.55 (95% CI, 0.99-2.41) and 4.75 (95% CI, 3.22-7.01) for FPG-CV, respectively. The risks of diabetic nephropathy for HbA1c-CV and FPG-CV stratified according to age, gender, renal function, and hypertension status were provided.
  
  
  CONCLUSIONS
  Annual FPG and HbA1c variations have a strong association with diabetic nephropathy in patients with type 2 diabetes. Whether intervention for reducing glucose variation should be administered needs to be examined in a future study.
authors.affiliation: Department of Family Medicine, China Medical University Hospital, Taichung, Taiwan; School of Medicine, College of Medicine, China Medical University, Taichung, Taiwan; Department of Medical Research, China Medical University Hospital, Taichung, Taiwan.
authors.forename: Cheng-Chieh
authors.initials: CC
authors.lastname: Lin
authors.forename: Ching-Chu
authors.initials: CC
authors.lastname: Chen
authors.forename: Fei-Na
authors.initials: FN
authors.lastname: Chen
authors.forename: Chia-Ing
authors.initials: CI
authors.lastname: Li
authors.forename: Chiu-Shong
authors.initials: CS
authors.lastname: Liu
authors.forename: Wen-Yuan
authors.initials: WY
authors.lastname: Lin
authors.forename: Sing-Yu
authors.initials: SY
authors.lastname: Yang
authors.forename: Cheng-Chun
authors.initials: CC
authors.lastname: Lee
authors.forename: Tsai-Chung
authors.initials: TC
authors.lastname: Li
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D001786:Blood Glucose / Q000378:metabolism*; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000150:complications*; D003928:Diabetic Nephropathies / Q000097:blood / Q000175:diagnosis / Q000453:epidemiology / Q000209:etiology*; D005260:Female; D005500:Follow-Up Studies; D006442:Glycated Hemoglobin / Q000378:metabolism*; D006801:Humans; D015994:Incidence; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011379:Prognosis; D016016:Proportional Hazards Models; D012307:Risk Factors
chemical_list: D015415:Biomarkers; D001786:Blood Glucose; D006442:Glycated Hemoglobin; C517652:hemoglobin A1c protein, human
keywords: Diabetic nephropathy; Fasting plasma glucose; Hemoglobin A(1c); Type 2 diabetes