Impact of hypoglycemic events and HbA1c level on sulfonylurea discontinuation and down-titration

Background: A retrospective cohort study using GE Centricity electronic medical records assessed the association between post-index hypoglycemia and HbA1c with discontinuation and down-titration of sulfonylureas among patients with Type 2 diabetes mellitus.

Methods: Adult patients with an index prescription for a sulfonylurea and ≥12 months’ continuous records pre- and post-index were eligible. Sulfonylurea discontinuation and down-titration was assessed 1-year post-index. Discontinuation occurred if the date of a prescription was >90 days from the preceding prescription plus days of supply. Down-titration occurred when a subsequent prescription was lower than the index dose. Cox regression assessed the association between post-index hypoglycemia and HbA1c with time to sulfonylurea discontinuation and down-titration, as well as other factors.

Results: 28,371 participants were included in the study; 13,459 (47.4%) were discontinuers, 717 (2.5%) were down-titraters, and 14,195 (50.0%) were continuers. 0.6% of continuers experienced hypoglycemia 1-year post-index, compared with 3.1% of down-titraters and 0.8% of discontinuers (< 0.0001). Patients with post-index hypoglycemia had a significantly higher rate of discontinuation (hazard ratio [HR] = 1.82, 95% CI: 1.47–2.23) and down-titration (HR = 4.25, 95% CI: 1.92–8.03). Patients with higher post-index HbA1c and use of 2nd generation sulfonylureas had an increased rate of discontinuation (HR = 1.05, 95% CI: 1.04–1.06; HR = 1.19, 95% CI: 1.14–1.24, respectively).

Conclusion: Approximately half of participants who initiated sulfonylureas discontinued or down-titrated therapy within one year. Both post-index hypoglycemia and higher HbA1c were significant risk factors for sulfonylurea treatment change.