HbA1c target achievement in the elderly: results of the Titration and Optimization trial for initiation of insulin glargine 100 U/mL in patients with type 2 diabetes poorly controlled on oral antidiabetic drugs

Objectives: To identify real-world, age-related trends in the use of insulin glargine 100 U/mL (Gla-100) as part of basal-supported oral therapy (BOT).

Research design and methods: The prospective, observational Titration and Optimization registry enrolled patients with poorly controlled type 2 diabetes mellitus initiated on Gla-100 BOT. The primary outcome was the proportion of patients with capillary fasting blood glucose (FBG) ≤110 mg/dL on ≥2 occasions and/or who met their individual HbA1c target within 12 months.

Results: 2462 patients were analyzed (<65 years: n=1122; 65-74 years: n=771; ≥75 years: n=569). Diabetes duration (6.8, 8.9, and 11.2 years, p<0.0001) and proportion of women (40.7%, 47.9%, and 55.7%, p<0.0001) increased with age. Baseline HbA1c was highest in <65-year-olds (8.6% vs 8.4% and 8.5%, p<0.0001). Gla-100 up-titration until 12 months was highest in <65-year-olds (+11.6 U/day), compared with 65-74 (+10.2 U/day) and ≥75 years (+8.8; p<0.0001) but similar by units per kilogram, as was the decrease in FBG (<65: -64.1 mg/dL; 65-74: -56.1 mg/dL; ≥75: -53.4 mg/dL) and HbA1c (<65: -1.47%; 65-74: -1.31%; ≥75: -1.22%, p<0.0001). At 12 months, 65.9% of participants met the primary endpoint, with no significant difference between age groups. The proportion achieving their individual HbA1c target was lower for <65-year-olds (46.0% vs 54.3% and 54.7%; p<0.02). Symptomatic hypoglycemia incidence was more common in the ≥75-year-old group (3.4% vs 1.4% and 1.4%; p=0.0126).

Conclusions: BOT with Gla-100 results in similar improvements of glycemic values with low risk of hypoglycemia across age groups. Given the link between HbA1c and long-term cardiovascular risk, ensuring appropriately stringent target-setting, intensification of basal insulin and making sure hypoglycemia is avoided is of paramount importance.

Trial registration number: Database: https://awbdb.bfarm.de; Identifier: 1641; Date of registration: September 23, 2013.