Risk factor combos predict diabetes treatment response better

The ratios between disease duration to age at diagnosis and between glycated haemoglobin (HbA1c) to C-peptide reactivity (CPR), when combined together, seem to be important determinants of response to medication among patients with type 2 diabetes, a recent Japan study has found.

The study included 7,009 diabetics who were grouped into three according to the medication taken: oral antidiabetic drugs (OADs; n=6,282), insulin (n=695), and glucagon-like peptide-1 receptor agonist (n=32). The primary outcome was a receiver operating characteristic (ROC) curve for the prediction of insulin treatment.

Logistic regression analysis found that age at diagnosis, disease duration, HbA1c, and serum CPR at the start of treatment were all correlated with the probability of insulin treatment.

ROC analysis verified that 1/age at diagnosis (area under the curve [AUC], 0.631, 95 percent confidence interval [CI], 0.609–0.653), disease duration (AUC, 0.670, 95 percent CI, 0.645–0.694), and HbA1c at treatment initiation (AUC, 0.635, 95 percent CI, 0.611–0.659) were all good predictors of insulin treatment.

AUC values for systolic blood pressure and body mass index were both lower than 0.6 and were deemed as insufficient for prediction.

A subsequent ROC curve analysis was carried out to assess the predictive value of combinations of factors. The ratio between disease duration and age, multiplied by 43, and combined with HbA1c, yielded a high AUC of 0.727 (95 percent CI, 0.707–0.748).

In a parallel analysis in a sample of 1,043 patients (864 on OADs, 179 on insulin), the ratio between disease duration and age at diagnosis, multiplied by 21, and combined with the ratio between HbA1c and CPR, yielded the best predictive value, with an AUC of 0.750 (95 percent CI, 0.709–0.792).

“[T]hese collective risk factors are effective predictors of patient responses to the medication. This information would need to be practically applied for the medications in a clinical setting, although diabetes is the result of more collective effects on several processes that contribute to the risk,” the researchers said.