Progression to microalbuminuria in type 1 diabetes: development and validation of a prediction rule.
OBJECTIVE
Microalbuminuria is common in type 1 diabetes and is associated with an increased risk of renal and cardiovascular disease. We aimed to develop and validate a clinical prediction rule that estimates the absolute risk of microalbuminuria.


METHODS
Data from the European Diabetes Prospective Complications Study (n = 1115) were used to develop the prediction rule (development set). Multivariable logistic regression analysis was used to assess the association between potential predictors and progression to microalbuminuria within 7 years. The performance of the prediction rule was assessed with calibration and discrimination (concordance statistic [c-statistic]) measures. The rule was validated in three other diabetes studies (Pittsburgh Epidemiology of Diabetes Complications [EDC] study, Finnish Diabetic Nephropathy [FinnDiane] study and Coronary Artery Calcification in Type 1 Diabetes [CACTI] study).


RESULTS
Of patients in the development set, 13% were microalbuminuric after 7 years. Glycosylated haemoglobin, AER, WHR, BMI and ever smoking were found to be the most important predictors. A high-risk group (n = 87 [8%]) was identified with a risk of progression to microalbuminuria of 32%. Predictions showed reasonable discriminative ability, with c-statistic of 0.71. The rule showed good calibration and discrimination in EDC, FinnDiane and CACTI (c-statistic 0.71, 0.79 and 0.79, respectively).


CONCLUSIONS
We developed and validated a clinical prediction rule that uses relatively easily obtainable patient characteristics to predict microalbuminuria in patients with type 1 diabetes. This rule can help clinicians to decide on more frequent check-ups for patients at high risk of microalbuminuria in order to prevent long-term chronic complications.
Vergouwe
Y
Y
Julius Center for Health Sciences and Primary Care, University Medical Centre Utrecht, Str 6.131, PO Box 85500, 3508 GA, Utrecht, the Netherlands. y.vergouwe@umcutrecht.nl
Soedamah-Muthu
S S
SS
Zgibor
J
J
Chaturvedi
N
N
Forsblom
C
C
Snell-Bergeon
J K
JK
Maahs
D M
DM
Groop
P-H
PH
Rewers
M
M
Orchard
T J
TJ
Fuller
J H
JH
Moons
K G M
KG
D000328:Adult; D000419:Albuminuria / Q000453:epidemiology*; D056808:Biostatistics / Q000379:methods; D001794:Blood Pressure; D015992:Body Mass Index; D002138:Calibration; D048909:Diabetes Complications / Q000453:epidemiology; D003922:Diabetes Mellitus, Type 1 / Q000503:physiopathology* / Q000652:urine; D003925:Diabetic Angiopathies / Q000453:epidemiology; D003928:Diabetic Nephropathies / Q000453:epidemiology; D018450:Disease Progression; D005060:Europe; D005260:Female; D005387:Finland; D006801:Humans; D008297:Male; D011237:Predictive Value of Tests; D011446:Prospective Studies; D012044:Regression Analysis; D015203:Reproducibility of Results; D049629:Waist-Hip Ratio