Vol.2, No.2, 227-233 (2012) Journal of Diabetes Mellitus http://dx.doi.org/10.4236/jdm.2012.22036 The development and validation of a risk score for predicting microalbuminuria in type 2 diabetic patients * Sirima Mongkolsomlit 1 , Petch Rawdaree 2 , Chulalux Komoltri 3 , Chamaiporn Tawichasri 1 , Jayanton Patumanond 1# 1 Department of Community Medicine, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand; # Corresponding Author: jayantorn.s@gmail.com 2 Department of Medicine, Bangkok Metropolitan Medical College and Vajira Hospital, Bangkok, Thailand 3 Department of Clinical Epidemiology, Faculty of Medicine, Siriraj Hospital, Bangkok, Thailand Received 10 February 2012; revised 18 March 2012; accepted 26 April 2012 ABSTRACT Objective: To develop and validate a prognostic scoring scheme for the prediction of microal- buminuria in type 2 diabetic patients of Thai descent. Methods: The clinical information from type 2 diabetic patients who were treated at community hospitals was used to develop a prediction model (derivation set). The model evaluated at a tertiary hospital (validation set). A stepwise logistic regression model was used to identify the independent risk variables from the derivation set and a simple point scoring system was derived from the beta-coefficients. The risk scoring scheme was validated by the validation set. Results: The risk scoring scheme is based on six risk predictors: the duration of diabetes, age at the onset of diabetes, systolic blood pressure, low density lipoprotein levels, creati- nine levels, and alcohol consumption. The total score ranged from 0 to 11.5. The likelihood of microalbuminuria in patients with low risk (scores ≤ 2) was 0.28, with moderate risk (scores 2.5 to 5.5) was 0.86, and high risk (scores ≥ 6) was 7.36. The area under the ROC curve of the derivation set and validation set were 0.768 (95% CI 0.73 - 0.81) and 0.758 (95% CI 0.70 - 0.80), re- spectively. Conclusion: Our scoring system is a simple and reasonably accurate method for predicting the future presence of microalbu- minuria in type 2 diabetic patients. Keywords: Microalbuminuria; Risk Score; Type 2 Diabetes; RIsk Factor; Scoring Scheme 1. INTRODUCTION Microalbuminuria is an early predictor of the renal, cardiovascular and retinopathy complications of diabetes [1-5]. The American Diabetes Association (ADA) rec- ommends that a standard screening test for microalbu- minuria should be used at diagnosis and at least yearly thereafter in type 2 diabetes [6]. Previous studies re- ported that there were only 2.1% of diabetes patients in the Mid-Atlantic region population of privately insured individuals received a microalbuminuria test [7]. In Thailand, around 41.0% of type 2 diabetes patients in tertiary care units were not screened for microalbuminu- ria [8]. There are two methods now readily available for mi- croalbuminuria diagnosis. Firstly, urinary concentrations of very small amounts of albumin can be determined quantitatively, this method usually involves radioimmu- noassay which has high sensitivity and specificity but quite expensive and the most of the primary care units in Thailand have a least performance for this method in screening tests for microalbuminuria. Secondly, qualita- tive methods can be used to screen for microalbuminuria; these are more readily available for use in the clinic, less complicated and cheaper than quantitative assessments but they are also less accurate and less specific [9]. Both methods required three urine specimens collection within twelve months period and obtained on different days. If two out of three are positive then the patient still has mi- croalbuminuria and only one or none out of the three are positive then the microalbuminuria has regressed [6]. These are not convenient for patients and they may be unable or unwilling to have the test performed. We found no study that has been conducted to assess the predictive value of a combination of the risk factors for microalbuminuria. The risk of developing microal- buminuria in type 2 diabetes depends on several deter- * Grant support: This project was supported by grants from the Faculty of Medicine Research Fund, Chiang Mai University, Thailand. Conflict of interest: The authors declare that they have no conflict of interest. Copyright © 2012 SciRes. OPEN ACCESS