Abstract
BACKGROUND: We examined the initiation of insulin therapy in patients with poorly controlled type 2 diabetes mellitus (T2DM), analyzed their glycemic responses, and compared patient profiles based on glycemic outcomes. METHODS: Patients with T2DM initiated on insulin therapy were retrospectively analyzed. Data were collected from endocrinology clinic before and 3 and 6 months after insulin initiation. The primary outcome was hemoglobin A1c (HbA1c) level 6 months after commencing insulin treatment. Secondary outcomes included HbA1c levels at 3 months after insulin treatment and fasting blood glucose levels at 3 and 6 months after treatment. We analyzed the effects of insulin initiation and categorized patients based on their 6-month HbA1c levels: below the median of 7.8% (better response) and above 7.8% (worse response). Additionally, we evaluated patients based on HbA1c changes at 6 months, with greater or lesser changes defined by the cohort's median change of -1.4%. RESULTS: Insulin therapy significantly reduced HbA1c (from 9.8% to 8.2%) and fasting blood glucose levels (from 221.4 to 147.2 mg/dL) within 3 months. After 6 months, HbA1c and fasting blood glucose levels decreased by 2.1% (9.8%-7.7%) and 77.2 mg/dL (221.4-144.2 mg/dL), respectively. Patients who responded better to insulin treatment showed lower fasting blood glucose levels by 6 months after insulin initiation and lower HbA1c levels as soon as 3 months after initiation. Patients with higher baseline glycemic profiles experienced significantly greater HbA1c reductions at 6 months post-treatment. CONCLUSION: Insulin therapy significantly improved glycemic control in patients with T2DM within 3 months after initiation. Patients with higher baseline glycemic profiles experienced greater responses to insulin therapy.