Proportion and characteristics of patients with Type 2 diabetes mellitus initiating basal insulin therapy using a basal-bolus regimen

Abstract Background: To explore the proportion and characteristics of patients with Type 2 diabetes mellitus (T2DM) uncontrolled by oral antidiabetic drugs (OADs) who initiated basal insulin (BI) therapy using a basal-bolus regimen. Methods: This multicenter, observational, prospective study included a representative sample of 18,995 Chinese insulin-naïve T2DM patients who initiated BI therapy due to uncontrolled hyperglycemia by OADs. The type and dose of BI as well as other treatment regimens depended on physician’s discretion and patient’s willingness. Proportion of patients initiating basal-bolus insulin and associated factors were analyzed. Results: Basal-bolus accounted for 24.6% of patients initiating BI, of whom 97.8% initiated a full basal-bolus regimen. In the multivariate logistic regression, factors significantly associated with initiating basal-bolus regimen were tertiary hospital, in-patients, younger age, higher BMI, longer diabetes duration, more complications, higher HbA1c level, low self-monitoring of blood glucose (SMBG) frequency before, one OAD used before, no concomitant OAD, and initiating Neutral Protamine Hagedorn (NPH). About half of patients initiating basal-bolus persisted on the same insulin regimen at 3-month. Glycemic control rates (HbA1c<7%) at 6 months were 37.6% and 41.8% in basal-bolus and BI alone, respectively (p<0.0001). In patients with at least one complication, basal-bolus showed significantly lower glycemic control compared with BI alone (33.4% vs 39.8%, P<0.0001). Conclusions: The findings suggest a high proportion of patients with T2DM initiating basal-bolus insulin. Tertiary hospital, in-patients, younger age, higher BMI, longer diabetes duration, more complications, higher HbA1c level, low SMBG frequency before, one OAD used before, no concomitant OAD, and concomitant NPH were related to higher odds of initiating basal-bolus.