Elevated haemoglobin A1c but not fasting plasma glucose conveys risk of chronic kidney disease in non-diabetic individuals

Chronic Microvascular Complications in Prediabetic States—An Overview

“…For some years, evidence for a correlation between an increased risk of chronic kidney disease (CKD) and diabetic kidney disease (DKD) in prediabetes has been recorded [ 35 , 46 ]. Characteristic features found in 14 cohort studies are summarized in Table 2 [ 47 , 48 , 49 , 50 , 51 , 52 , 53 , 54 , 55 , 56 , 57 , 58 , 59 , 60 ]. Half of the studies [ 48 , 49 , 50 , 51 , 52 , 53 , 54 ] were designed mainly to assess the relationship between metabolic syndrome and CKD.…”

“…The size of groups in the presented cohorts ranged from 2398 to 118,924. The European population [ 55 , 56 , 58 ] and the American population [ 47 , 48 , 50 ] were each assessed in three studies, while eight studies concerned the Asian population [ 49 , 51 , 52 , 53 , 54 , 57 , 59 , 60 ]. Some of the European and American studies included multi-ethnic populations, but the white population constituted at least 50% in each of them.…”

“…The definition of prediabetes varied in the studies: eight studies considered only IFG, and IFG + IGT, IFG + HbA1c, and IFG + IGT + HbA1c combinations were considered in two studies each. In nine studies, IFG was defined as fasting glucose between 110 and 125 mg/dL; in four studies, this was 100–125 mg/dL, while, in one study, two ranges were taken into consideration [ 57 ]. In all the studies scrutinized here, people with diabetes were excluded from participation in the research.…”

“…In eight studies, estimated glomerular filtration rate (eGFR) < 60 mL/min per 1.73 m 2 was assumed when defining CKD in line with Modification of Diet in Renal Disease (MDRD); in four studies, Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) was used, and single studies employed Cockroft–Gault equation [ 50 ], or isotope dilution mass spectrometry traceable 4-variable Modification of Diet in Renal Disease (IDMS-MDRD study equation) [ 57 ]. Five studies additionally included microalbuminuria or proteinuria in the definition of CKD [ 49 , 50 , 53 , 57 , 58 ]. The degree to which the co-variables were adapted differed in particular studies; only six studies included the baseline eGFR [ 47 , 52 , 55 , 57 , 59 , 60 ].…”

Risk of chronic kidney disease defined by decreased estimated glomerular filtration rate in individuals with different prediabetic phenotypes: results from a prospective cohort study in China

“…16 17 Fasting plasma glucose (FPG) and 2-hour plasma glucose (2hPG) have been commonly used for the diagnosis of diabetes; and recently, glycated hemoglobin A 1c (HbA 1c ), a measure of long term glucose homeostasis, has also been recommended for diagnosis of diabetes. The KORA study suggested that FPG, 2hPG and HbA 1c were all associated with CKD 15 ; however, studies from China, Japan and Korea indicated that it was elevated HbA 1c or impaired glucose tolerance (IGT), but not impaired fasting glucose (IFG) increased the risk for CKD, [18][19][20] and one study based on the Systolic Blood Pressure Intervention Trial concluded that FPG was not associated with the development of CKD. 21 Therefore, which of these prediabetic glycemic indices is/are genuinely associated with the occurrence of CKD remain unclear.…”