Tubeless Insulin Pump Therapy Leads to Greater Reductions in HbA1c

Insulin injection
Previous studies have shown that continuous subcutaneous insulin infusions can lead to improvements in clinical and quality of life benefits as compared to multiple daily injections of insulin. In this study, researchers led by Sanjeev Mehta, MD, MPH, of the Joslin Diabetes Center at Harvard University, test that concept in type 1 diabetes patients.

Initiation of tubeless insulin pump therapy is associated with an improvement in HbA1c at 12 months compared with prior therapy, according to research results published in Clinical Diabetes.

Researchers conducted a multicenter, retrospective, electronic health record-based research study in order to evaluate the effects of 12 months of tubeless insulin pump treatment on glycemic control in a cohort of adults with type 1 diabetes who transitioned from previous insulin therapy with either multiple daily injection or continuous subcutaneous insulin infusion.

The primary study endpoint was HbA1c change from baseline to 12 months after initiation of treatment with a tubeless insulin pump. Secondary outcomes included body weight change from baseline to 12 months post-tubeless insulin pump initiation.

In total, 156 adults (mean age, 43.7 ± 14 years; 86% women) were included in the study. A majority of these patients utilized multiple daily injections as their previous method of treatment. Patients had a higher baseline HbA1c compared with the continuous subcutaneous insulin injection group. Interim data were available at 3 and 6 months in 54% and 50% of patients.

Full cohort results showed a clinically significant HbA1c reduction at 12 months following tubeless insulin pump therapy initiation from 8.1(± 1.5)% to 7.8(± 1.3)% (change, -0.3%; 95% CI, -0.5 to -0.1%). HbA1c improvement was also noted at 3 and 6 months, with changes of -0.4% and -0.3%, respectively.

Those who transitioned from multiple daily injections experienced a significant HbA1c decrease of -0.4%, from 8.2(± 1.6)% to 7.8(± 1.2%) at 12 months. No significant HbA1c change was seen for the continuous subcutaneous insulin injection group (mean HbA1c decrease, -0.1%). Participants who had a baseline HbA1c ≥9% (n=40, 65% previous multiple daily injection patients) showed a significant HbA1c decrease at month 12 following the transition (-1.2±1.7%); patients with a baseline HbA1c <9% maintained similar glycemic control.

Investigators observed significant glycemic control improvement following the initiation of tubeless pump therapy, with an increase from 16-24% of patients who met the American Diabetes Association treatment target HbA1c less than 7% at 12 months. Results were similar across subgroups based on previous insulin therapy modality.

No clinically significant increase in body weight at 12 months was noted, with weight remaining stable regardless of previous insulin therapy.

Study limitations include those inherent to the retrospective nature of the research, the lack of control group, exclusion of patients without 12-month HbA1c data, and no data surrounding patient satisfaction or quality of life.

“Future evaluations using mixed methods-based approaches may provide additional insight into patient preference for the tubeless insulin pump in the current era of emerging advanced diabetes technologies,” the researchers concluded.

Disclosure: Several study authors declared affiliations with the pharmaceutical industry. Please see the original reference for a full list of authors’ disclosures.


Mehta SN, Tinsley LJ, Kruger D, et al. Improved glycemic control following transition to tubeless insulin pump therapy in adults with type 1 diabetes. Clin Diabetes. 2021;39(1):72-79.