Prognostic association of HbA1c and fasting plasma glucose with reduced kidney function in subjects with and without diabetes mellitus. Results from a population-based cohort study from Germany.
OBJECTIVE
To determine the risk for incident reduced kidney function (RKF) of subjects with pre-diabetes (impaired fasting glucose (IFG, 5.6-6.9 mmol/L)) or HbA1c-defined pre-diabetes (5.7%-6.4%) and to determine dose-response relationships of fasting glucose and HbA1c with RKF in subjects with manifest diabetes mellitus.


METHODS
In a German population-based cohort, recruited 2000-2002 with ages 50-74 years, log-binomial regression was used to estimate relative risks (RR) with 95% confidence intervals (95%CI) and restricted cubic splines to plot dose-response relationships.


RESULTS
During 8 years of follow-up, 678 of 3538 study participants developed primary RKF. Although RKF risk factor prevalences and RKF incidences were higher in subjects with pre-diabetes than in subjects with normal FPG and/or HbA1c levels, an increased risk did not persist after adjusting for established cardiovascular risk factors (RR(IFG): 0.97 (95% CI: 0.75-1.25) and RR(HbA1c-defined pre-diabetes): 1.03 (95% CI: 0.86-1.23)). In subjects with manifest diabetes, RKF risk increased linearly to a more than three-fold risk with increasing fasting glucose and HbA1c levels (at HbA1c>6.4%).


CONCLUSIONS
This study provides further evidence that pre-diabetes may not directly contribute to the development of kidney disease. Subjects with pre-diabetes might nevertheless profit from preventive efforts reducing their cardiovascular risk profile because cardiovascular and kidney disease share common risk factors.
Division of Clinical Epidemiology and Aging Research, German Cancer Research Center, Heidelberg, Germany. Electronic address: b.schoettker@dkfz.de.
B
B
Schöttker
H
H
Brenner
W
W
Koenig
H
H
Müller
D
D
Rothenbacher
D000368:Aged; D001786:Blood Glucose / Q000378:metabolism*; D015331:Cohort Studies; D003404:Creatinine / Q000097:blood; D003924:Diabetes Mellitus, Type 2 / Q000097:blood*; D003928:Diabetic Nephropathies / Q000097:blood*; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D005858:Germany; D005919:Glomerular Filtration Rate / Q000502:physiology; D005951:Glucose Tolerance Test; D006442:Glycated Hemoglobin / Q000378:metabolism*; D006801:Humans; D007677:Kidney Function Tests; D008297:Male; D008875:Middle Aged; D011236:Prediabetic State / Q000097:blood*; D011379:Prognosis; D012307:Risk Factors
D001786:Blood Glucose; D003404:Creatinine; D006442:Glycated Hemoglobin; C517652:hemoglobin A1c protein, human
BMI; Blood glucose; CKD; Cohort study; Diabetes mellitus, type 2; Epidemiology; FPG; HbA(1c); IFG; IGT; Impaired fasting glucose; Impaired glucose tolerance; Kidney disease; OGTT; OR; Odds ratio; Prediabetes; RKF; RR; Relative risk; body mass index; chronic kidney disease; fasting plasma glucose; glycated hemoglobin A(1c); oral glucose tolerance test; reduced kidney function