Kanatsuka A, Sato Y, Higashi Y, et al. - Response to the medications for type 2 diabetes can be predicted through a collective risk factor consisting of the combination of disease duration-to-age at diagnosis and hemoglobin A1c (HbA1c)-to-C-peptide reactivity (CPR) ratios.

• The CoDiC database was used to analyze cohort studies across Japan from January 2005 to July 2018, by applying criterion that using insulin therapy indicates severe type 2 diabetes.

• Factors linked with the likelihood of insulin therapy included: age at diagnosis, disease span, HbA1c and serum CPR at medication initiation.

• These clinical factors were predictive of insulin treatment positivity, with an area under the curve of >0.600.

• For the disease duration-to-age at diagnosis ratio and HbA1c-to-CPR ratio, the area under the curve elevated to 0.674 and 0.720, respectively.

• Furthermore, there was an increase in area under the curve to 0.727 and 0.750 in the indices (duration-to-age ratio at diagnosis × 43 + HbA1c) and (duration-to-age ratio at diagnosis × 21 + HbA1c-to-CPR ratio), respectively.

• Post-stratification to three categories based on the indices, the upper one-third vs the lower one-third of patients had higher monthly HbA1c levels during 6 months of treatment.

• In addition, in the upper one-third, many patients failed to achieve the target HbA1c level (53 mmol/mol), although greater than fourfold more patients were given insulin in the upper one-third.