Undiagnosed diabetes in kidney transplant candidates: a case-finding strategy.
OBJECTIVE
Guidelines recommend that candidates for kidney transplantation (KTx) who do not have diabetes perform a pretransplantation oral glucose tolerance test (OGTT) when fasting plasma glucose (FPG) is <110 mg/dl (<6.1 mmol/L); however, the OGTT is potentially costly and cumbersome. We studied the role of the OGTT for diagnosing diabetes and the accuracy of FPG and glycated hemoglobin (HbA(1c)) for predicting a diabetic OGTT before KTx.


METHODS
In this cross-sectional study, 889 first single-kidney transplant candidates without diabetes, mainly white, performed an OGTT during the transplantation workup. Results were studied using receiver operating characteristic analysis.


RESULTS
Of 72 (8.1%) patients with undiagnosed diabetes, only 16 (22%) had a diabetic FPG (> or =126 mg/dl [> or =7.0 mmol/L]). In patients with a nondiabetic FPG, diabetes (2-hour plasma glucose [2h-PG] > or =200 mg/dl [> or =11.1 mmol/L]) was predicted by FPG but not by HbA(1c). Performing the OGTT in patients with FPG 92 to 125 mg/dl (5.1 to 6.9 mmol/L) identified 65 (90%) patients with diabetes (16 by FPG, 49 by 2h-PG) and required seven OGTTs per patient identified. Subjecting all patients with FPG <110 mg/dl (<6.1 mmol/L) to the OGTT identified 60 (83%) patients with diabetes (16 by FPG, 44 by 2h-PG) but required 14 OGTTs per patient.


CONCLUSIONS
The OGTT was paramount in finding most cases of undiagnosed diabetes before KTx. FPG but not HbA(1c) predicted a diabetic OGTT. We suggest that white KTx candidates without diabetes perform a pretransplantation OGTT when FPG is 92 to 125 mg/dl (5.1 to 6.9 mmol/L).
Laboratory for Renal Physiology, Section for Nephrology, Department of Medicine, Oslo University Hospital Rikshospitalet, 0027 Oslo, Norway. henrik.andreas.bergrem@rikshospitalet.no
Henrik Andreas
HA
Bergrem
Tone Gretland
TG
Valderhaug
Anders
A
Hartmann
Jøran
J
Hjelmesaeth
Torbjørn
T
Leivestad
Harald
H
Bergrem
Trond
T
Jenssen
D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D001786:Blood Glucose / Q000378:metabolism*; D003430:Cross-Sectional Studies; D003920:Diabetes Mellitus / Q000097:blood / Q000175:diagnosis* / Q000208:ethnology; D005215:Fasting / Q000097:blood*; D005260:Female; D005951:Glucose Tolerance Test; D006442:Glycated Hemoglobin / Q000378:metabolism*; D006801:Humans; D007676:Kidney Failure, Chronic / Q000097:blood / Q000150:complications / Q000208:ethnology / Q000601:surgery*; D016030:Kidney Transplantation; D008297:Male; D008875:Middle Aged; D009664:Norway; D011237:Predictive Value of Tests; D012372:ROC Curve; D044465:White People
D015415:Biomarkers; D001786:Blood Glucose; D006442:Glycated Hemoglobin; C517652:hemoglobin A1c protein, human