Should we screen for risk of type 1 diabetes?

T hus far, the consensus within the diabetes community has been that we should screen for risk of type 1 diabetes only in the context of research studies. This view follows the World Health Organization recommendation on screening of clinical conditions, which states that you should screen only for diseases for which there is effective prevention or treatment (1). Data from the DAISY study suggest that the identification of subjects at increased risk for type 1 diabetes and prospective monitoring of risk individuals results in early diagnosis of clinical disease and the avoidance of severe metabolic decompensation at diagnosis among those who progress to overt diabetes (2). The Finnish DIPP Study has generated similar experiences by reducing the frequency of diabetic ketoacidosis at diagnosis from 20 to Ͻ2%lished data). Given that diabetic ketoaci-dosis is a potentially life-threatening condition and that severe metabolic de-compensation at diagnosis is associated with a reduced residual ␤-cell function and impaired metabolic control subsequently (3,4), one may ask whether it would be meaningful to screen for high-risk individuals and monitor them sequentially for progression to type 1 diabetes. In this issue, Sosenko et al. (5) introduce a risk score for type 1 diabetes derived from the Diabetes Prevention Trial– Type 1 (DPT-1) (5). The authors divided the DPT-1 cohort into development and validation samples. From the former, a risk score was established based on a model including the logarithm of BMI, age, the logarithm of fasting C-peptide, and total glucose and C-peptide sums from a 2-h oral glucose tolerance test (OGTT). This risk score strongly predicted type 1 diabetes in the validation sample. The predictive value of the risk score did not increase by including a reduced first-phase insulin response (FPIR) from an intravenous glucose tolerance test (IVGTT) as a predictor. A final risk score was derived from all participants based on the variables listed above. The change in risk score from baseline up to 1 year was also highly predictive of type 1 diabetes. The authors conclude that a risk score based on age, BMI, and OGTT indexes appears to accurately predict type 1 diabetes in islet cell autoantibody (ICA)-positive relatives of affected patients. The authors admit that their risk score has its limitations. First of all, it is based an a group of relatives whose selection was contingent on ICA positivity, and, accordingly, the extent to which the risk score is applicable to relatives …