Novel predictors of overt nephropathy in subjects with type 1 diabetes. A nested case control study from the Pittsburgh Epidemiology of Diabetes Complications cohort.
BACKGROUND
Predictors of diabetic nephropathy are only partly known and traditional risk factors do not adequately explain disease risk. We thus examined novel risk factors for overt nephropathy (ON) in type 1 diabetes.


METHODS
The EDC is a prospective study of childhood-onset type 1 diabetes. When first seen (1986-1988), mean age was 28 and diabetes duration 19 years. In the subsequent 10 years, 56 of 485 subjects without ON in 1986-88 developed ON. An age, duration (+/-3 years), and sex-matched control was identified for 47 cases. Forty-two matched pairs had available stored plasma samples obtained prior to ON onset in cases, and complete standard risk factor data.


RESULTS
Cases had a higher baseline albumin excretion rate (AER), HbA1, pulse rate, non-HDL cholesterol, fibrinogen, small LDL and lower eGDR and LDL particle size compared to controls (all P values<0.05). Multiple measures of immune complexes were increased in cases (P<0.05), whereas borderline elevations were seen for total antioxidant reserve (P=0.06) and retinol (P=0.08). Multivariably, other than AER, LDL particle size and IgG-IC were predictive beyond the standard predictors.


CONCLUSIONS
Besides AER, the immunecomplexes and lipoprotein subclasses may provide additional information in the assessment of ON risk in type 1 diabetes.
Yishak
Aklilu A
AA
Department of Medicine, University of Pittsburgh School of Medicine, and Veterans Pittsburgh Health Care System of Pittsburgh, Pittsburgh, PA 15213, USA.
Costacou
Tina
T
Virella
Gabriel
G
Zgibor
Janice
J
Fried
Linda
L
Walsh
Michael
M
Evans
Rhobert W
RW
Lopes-Virella
Maria
M
Kagan
Valerian E
VE
Otvos
James
J
Orchard
Trevor J
TJ
D000293:Adolescent; D000328:Adult; D017677:Age Distribution; D000936:Antigen-Antibody Complex / Q000032:analysis; D015415:Biomarkers / Q000032:analysis; D001786:Blood Glucose / Q000032:analysis; D016022:Case-Control Studies; D008076:Cholesterol, HDL / Q000032:analysis; D008078:Cholesterol, LDL / Q000032:analysis; D015331:Cohort Studies; D015897:Comorbidity; D003922:Diabetes Mellitus, Type 1 / Q000175:diagnosis* / Q000453:epidemiology*; D003928:Diabetic Nephropathies / Q000175:diagnosis* / Q000453:epidemiology*; D005260:Female; D006442:Glycated Hemoglobin / Q000032:analysis; D006801:Humans; D007677:Kidney Function Tests; D008297:Male; D015999:Multivariate Analysis; D011237:Predictive Value of Tests; D015995:Prevalence; D011336:Probability; D011379:Prognosis; D012016:Reference Values; D018570:Risk Assessment; D012720:Severity of Illness Index; D017678:Sex Distribution
D000936:Antigen-Antibody Complex; D015415:Biomarkers; D001786:Blood Glucose; D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D006442:Glycated Hemoglobin