Optimal HbA1c cutoff for detecting diabetic retinopathy.
The associations between high glucose levels and diabetic retinopathy have been the basis for the diagnosis of diabetes. We aimed to provide updated data on the relationship between HbA1c and diabetic retinopathy, and to assess the diagnostic accuracy of the proposed HbA1c cutoff for detecting diabetic retinopathy. This cross-sectional study included 3,403 adults from the 2009 to 2010 Ansung Cohort Study. Retinopathy was assessed with single-field nonmydriatic fundus photography and graded according to the International Clinical Diabetic Retinopathy Disease Severity Scale. HbA1c was measured by standardized assay using high performance liquid chromatography. Based on deciles distribution, the prevalence of retinopathy was very low until the HbA1c range of 48-51 mmol/mol (6.5-6.8 %). The optimal HbA1c cutoff for detecting any diabetic retinopathy was 49 mmol/mol (6.6 %), moderate or severer retinopathy was 52 mmol/mol (6.9 %) from receiver operating characteristic curve analysis. The proposed HbA1c threshold of 48 mmol/mol (6.5 %) from American Diabetes Association produced comparable accuracy for identifying both any and moderate/severer retinopathy. This study confirmed that the proposed HbA1c threshold of 48 mmol/mol (6.5 %) allowed the proper detection of diabetic retinopathy. Our data support the judicious use of HbA1c for the diagnosis of diabetes and detecting diabetic retinopathy as well.
Department of Preventive Medicine, Ajou University School of Medicine, Suwon, South Korea.
Nam H
NH
Cho
Tae Hyuk
TH
Kim
Se Joon
SJ
Woo
Kyu Hyung
KH
Park
Soo
S
Lim
Young Min
YM
Cho
Kyong Soo
KS
Park
Hak C
HC
Jang
Sung Hee
SH
Choi
D000328:Adult; D000368:Aged; D002853:Chromatography, Liquid / Q000592:standards; D003430:Cross-Sectional Studies; D003930:Diabetic Retinopathy / Q000097:blood / Q000175:diagnosis* / Q000453:epidemiology; D005260:Female; D005951:Glucose Tolerance Test / Q000592:standards; D006442:Glycated Hemoglobin / Q000032:analysis*; D006801:Humans; D007723:Korea / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D015995:Prevalence; D012016:Reference Values; D012720:Severity of Illness Index
D006442:Glycated Hemoglobin; C517652:hemoglobin A1c protein, human