Development of a new scoring system for predicting the 5 year incidence of type 2 diabetes in Japan: the Toranomon Hospital Health Management Center Study 6 (TOPICS 6)

Abstract

Aims/hypothesis The aims of this study were to assess the clinical significance of introducing HbA 1c into a risk score for diabetes and to develop a scoring system to predict the 5 year incidence of diabetes in Japanese individuals. Methods The study included 7,654 non-diabetic individuals aged 40-75 years. Incident diabetes was defined as fasting plasma glucose (FPG) ≥7.0 mmol/l, HbA 1c ≥6.5% (48 mmol/mol) or self-reported clinician-diagnosed diabetes. We constructed a risk score using non-laboratory assessments (NLA) and evaluated improvements in risk prediction by adding elevated FPG, elevated HbA 1c or both to NLA. Results The discriminative ability of the NLA score (age, sex, family history of diabetes, current smoking and BMI) was 0.708. The difference in discrimination between the NLA + FPG and NLA + HbA 1c scores was non-significant (0.836 vs 0.837; p00.898). A risk score including family history of diabetes, smoking, obesity and both FPG and HbA 1c had the highest discrimination (0.887, 95% CI 0.871, 0.903). At an optimal cut-off point, sensitivity and specificity were high at 83.7% and 79.0%, respectively. After initial screening using NLA scores, subsequent information on either FPG or HbA 1c resulted in a net reclassification improvement of 42.7% or 52.3%, respectively (p<0.0001). When both were available, net reclassification improvement and integrated discrimination improvement were further improved at 56.7% (95% CI 47.3%, 66.1%) and 10.9% (9.7%, 12.1%), respectively.

Development of new diabetes risk scores on the basis of the current definition of diabetes in Japanese subjects [Rapid Communication]

“…Nonetheless, the performance of the invasive models was better than the non-invasive model, as reported previously [2,3]. This was expected because the individuals were more Prediction of DM by "FPG ≥126 mg/dL, random PG ≥200 mg/dL, HbA1c ≥6.5%, or receiving medical treatment for DM [6]" and "FPG ≥7.0 mmol/L, HbA1c ≥6.5% or self-reported clinician-diagnosed DM [14]" was reasonably accurate with C-statistics being 0.882 and 0.887, respectively. Nonetheless, the diagnosis was different from the current definition so that post-challenge PG was not included in the diagnostic criteria.…”

“…For smoking habit, the subject was classified as a smoker if currently smok-"HbA1c definition", respectively. RSs for DM diagnosed by "FPG, random PG, HbA1c or receiving medical treatment for diabetes [6]" and "FPG, HbA1c or self-reported clinician-diagnosed diabetes [14]" have been developed in Japan, but postchallenge PG was not used for the diagnosis of diabetes in these studies.…”

The potential of novel biomarkers to improve risk prediction of type 2 diabetes

“…In the multiethnic Atherosclerosis Risk in Communities (ARIC) [22]. Figure 1 and ESM Table 2 show that the separate addition of fasting glucose, HbA 1c or 2 h glucose to basic models with non-invasive variables leads to a strong increase in model accuracy [18,24,[36][37][38]. In several studies, HbA 1c improved the predictive power to a similar extent to fasting glucose.…”

Development of a Screening Score for Undiagnosed Diabetes and Its Application in Estimating Absolute Risk of Future Type 2 Diabetes in Japan: Toranomon Hospital Health Management Center Study 10 (TOPICS 10)

“…Recent studies (14,16,17) described the development of screening tools to identify individuals with prediabetes and undiagnosed diabetes. We recently published a report describing our development of a new risk scoring system for predicting the 5-year incidence of diabetes among nondiabetic individuals in a prospective setting (24). However, the utility of that risk score for identifying undiagnosed diabetes was not investigated because it was not originally designed to identify current diabetic patients.…”