946-P: Insulin Pump Therapy in Type 1 Diabetes—a Real-World Study of Mortality and Clinical Outcomes

Introduction & Objective: Clinical trials have demonstrated benefits of insulin pumps in type 1 diabetes (T1D). However, data from real-world studies is limited. We investigated the real-world impact of insulin pumps on glycaemia, diabetes complications and mortality when compared to multiple daily injections of insulin (MDI).

Methods: We performed a retrospective cohort study of all patients aged 18 or over with T1D on the TriNetX platform, a global collaborative network providing access to real time, anonymized medical records. We captured data from Jan 2018 to Oct 2023 to ensure that the results reflect recent advances in pump therapy.

Results: We identified 112,801 patients with T1D. Of this, 18,228 (16.2%) were treated with insulin pumps (mean age 36.9 years [SD 19.2], 44.8% male) and were propensity score-matched (1:1) to patients on MDI. All-cause mortality was significantly lower in the pump group at year 5 (RR 0.804 [0.726-0.891], p=0.014). There was no clinically significant percentage change difference in mean HbA1c at 5 years (mean percentage change -5.807% on pumps vs. -5.989% on MDI). The incidence of DKA was greater in the pump group at year 1 (RR 1.089 [1.020-1.162], p=0.010), however there was no difference each year from 2 to 5 years. There was a higher incidence of stroke (RR 1.364 [1.103-1.687], p=0.004) and ischemic heart disease (RR 1.214 [1.071-1.375], p=0.002) in year 1 in the pump group but not thereafter. The incidence of diabetes related eye disease remained elevated in the pump group at year 5 (RR 1.742 [1.613-1.881], p<0.001).

Conclusion: In a large real-world cohort of people with T1D, insulin pumps compared to MDI were associated with lower overall mortality. Clinically significant reductions in HbA1c were seen in both groups. The risk of DKA, stroke and ischemic heart disease was higher in the first year of pump use but with no difference compared to MDI at year 5. Increased diabetes related eye disease in the pump group may represent a legacy effect of prior sub-optimal control.