Continuous subcutaneous insulin infusion (CSII) treatment may improve long-term glycemic outcomes and enhance quality of life compared with a multiple daily injection (MDI) insulin regimen for people with type 1 diabetes. As the number of people treated with CSII via a tubeless insulin pump is increasing, there is growing interest in the long-term glycemic outcomes of this treatment option across diverse populations. This multicenter, retrospective study evaluated glycemic control in 156 adults with type 1 diabetes initiating tubeless insulin pump therapy following transition from either MDI or CSII with a tubed insulin pump. In this study, use of the tubeless insulin pump over 12 months was associated with significant improvement in A1C in adults with type 1 diabetes, most notably in those with an A1C ≥9.0% and those previously treated with MDI.
Multiple studies have demonstrated clinical and quality of life benefits of continuous subcutaneous insulin infusion (CSII) compared with a multiple daily injection (MDI) insulin regimen for the treatment of type 1 diabetes (
The Omnipod® Insulin Management System (Insulet Corp., Acton, MA) is a tubeless insulin pump that consists of the Pod, a small, adhesive, waterproof (IP28) wearable insulin patch pump with automated cannula insertion, and the personal diabetes manager (PDM), a handheld device used to wirelessly control and monitor the Pod (
As the number of people using tubeless insulin pump therapy increases, there is a growing need to understand the long-term clinical outcomes of this therapy in various populations. The objective of this study was to evaluate the effect of 12 months of treatment with the tubeless insulin pump on glycemic control in adults with type 1 diabetes following transition from their prior form of insulin therapy (MDI or CSII with a tubed insulin pump).
This was a multicenter, retrospective electronic health record–based clinical investigation.
Patients at participating sites in the United States who were ≥18 years of age, diagnosed with type 1 diabetes for ≥1 year as of 1 November 2013, and receiving treatment with either MDI or CSII with a tubed insulin pump before transitioning to the Omnipod system from November 2013 through July 2016 were eligible for inclusion.
Eligible patients were required to have an A1C measurement at Omnipod initiation (baseline) and at 1-year follow-up. A1C values were available in the electronic health records at the respective sites. All sites used an NGSP-standardized A1C methodology. Given variable outpatient follow-up in the real-world clinical setting, baseline A1C was defined as the A1C value closest to the initiation date, ranging from 3 months before to 1 month after initiation; follow-up A1C was defined as the A1C value closest to 12 months after initiation, ranging from 9 to 15 months post-initiation. Patients who became pregnant during the follow-up period were excluded. Institutional review board approval of the protocol was obtained from participating sites. Given the retrospective, de-identified data collection, the study was exempted from informed consent requirements.
The primary end point was change in A1C from the time of transition (baseline) to 12 months after initiation of the tubeless insulin pump. The change in A1C at 3 and 6 months post-tubeless insulin pump initiation and the change in A1C stratified by baseline A1C and by prior treatment modality (MDI or CSII with tubed insulin pump) were also analyzed. Secondary outcomes included change in body weight from baseline to 12 months post-tubeless insulin pump initiation.
Outcome measures were summarized as mean and SD across patients at the multiple time points of interest (baseline and 3, 6, and 12 months post-initiation of the tubeless pump). A dependent
A
Change in body weight was evaluated by a dependent
Statistical significance was defined as
A total of 156 patients with type 1 diabetes who met the inclusion criteria were identified across the study sites. Baseline characteristics are summarized in
Baseline Characteristics
Parameter | Patients ( |
---|---|
Age at tubeless pump start, years | 43.7 ± 14.0 |
Female | 86 (55) |
Race/ethnicity | |
Caucasian/non-Hispanic | 114 (73) |
Unknown | 28 (18) |
Black or African American | 13 (8) |
Asian | 1 (1) |
Prior treatment modality | |
MDI | 99 (63) |
CSII | 57 (37) |
A1C, % | |
Overall | 8.1 ± 1.5 |
Prior MDI treatment ( | 8.2 ± 1.6 |
Prior CSII treatment ( | 8.0 ± 1.4 |
BMI, kg/m2 | 26.9 ± 4.6 |
Results are mean ± SD or
Missing data for
Results from the full cohort of 156 patients (including both prior therapy modalities together) demonstrated a clinically significant reduction in A1C 12 months after initiating tubeless insulin pump therapy (
A1C post-tubeless insulin pump initiation compared with prior treatment in the full cohort of 156 adults with type 1 diabetes. Mean A1C is plotted at baseline with prior treatment, as well as for the 3-, 6-, and 12-month follow-up time points after tubeless insulin pump initiation. A1C at baseline was 8.1 ± 1.6% for the subsample with data at the 3-month follow-up time point (
Patients transitioning to the tubeless insulin pump from MDI (
Change in A1C at 12 months post-tubeless insulin pump initiation stratified by prior treatment in adults with type 1 diabetes. The change in A1C was significant for those previously treated with MDI (
Patients with baseline A1C ≥9% (
Change in A1C at 12 Months Post-Tubeless Insulin Pump Initiation Stratified by Baseline A1C
Baseline A1C Range | Baseline A1C, % | A1C 12 Months Post-Tubeless Pump Initiation, % | Change in A1C, % |
---|---|---|---|
<9.0% ( | 7.4 ± 0.7 | 7.5 ± 0.9 | 0.1 ± 0.7 |
≥9.0% ( | 10.1 ± 1.3 | 8.9 ± 1.7 | −1.2 ± 1.7 |
Data are mean ± SD.
As shown in
Proportion of patients in each A1C category at baseline on prior treatment and 12 months post-tubeless insulin pump initiation. There was a statistically significant shift from higher to lower category from baseline to post-tubeless insulin pump initiation (
There was no clinically significant increase in body weight 12 months following transition to the tubeless insulin pump (
Body Weight at 12 Months Post-Tubeless Insulin Pump Initiation Compared with Prior Treatment Overall and Stratified by Prior Treatment
Baseline Regimen | Baseline Weight, kg | Weight 12 Months Post–Tubeless Pump, kg | |
---|---|---|---|
Overall ( | 79.2 ± 16.4 | 79.8 ± 16.7 | 0.17 |
Prior MDI ( | 77.8 ± 16.3 | 77.9 ± 16.2 | 0.75 |
Prior CSII ( | 81.6 ± 16.6 | 82.9 ± 17.3 | 0.09 |
Data are mean ± SD. Missing data for
This multicenter, retrospective study demonstrated significant improvement in A1C in adults with type 1 diabetes 12 months after transitioning to the tubeless insulin pump. Improvement in A1C was also observed at the 3- and 6-month interim time points. The subgroup transitioning from MDI had a significant improvement in A1C, whereas the smaller subgroup transitioning from CSII with a tubed pump maintained comparable glycemic control between baseline and follow-up. The greatest decrease was noted in the subgroup with baseline A1C ≥9%, whereas A1C levels were stable between baseline and follow-up in the subgroup with baseline A1C <9%. The significant reductions in A1C observed in this study were achieved without an increase in body weight.
Real-world population data in routine clinical practice settings can provide important insight into factors affecting treatment choice and clinical outcomes in people with type 1 diabetes. Tubeless insulin pump therapy is a differentiated form of CSII that has been associated with improvements in glycemic control over the short term (3–7 months) across all ages (
In this study, the mean A1C of the full cohort (including both prior treatment modalities together) was significantly lower after 3, 6, and 12 months following transition to tubeless pump therapy. After 12 months of use, a clinically significant 0.3% reduction in A1C was observed, resulting in a mean A1C of 7.8 ± 1.3%. The A1C observed at the 12-month follow-up in this study is consistent with an analysis from the T1D Exchange Clinic Registry, which reported that CSII users have a mean A1C of 8.6 ± 1.6% for those aged 18–25 years, 7.7 ± 1.2% for those aged 26–49 years, and 7.6 ± 1.1% for those aged ≥50 years (an estimated average A1C of 8.0% for adult CSII users overall based on the sample size of each age-group) (
At 12 months, 24% of tubeless pump users in our study achieved the ADA treatment goal of A1C <7.0%, a notable increase of 8% from the proportion at goal prior to tubeless pump initiation. As a comparator, the T1D Exchange Clinic Registry reported that 21% of their adult participants achieved this treatment goal (
Patients with A1C ≥9% demonstrated the greatest reduction in A1C following transition to tubeless pump therapy, while a relatively stable level of glycemic control was maintained in patients with A1C <9% at baseline. Those with A1C ≥9% at baseline had a mean A1C of 10.1%, which was significantly reduced by 1.2% to 8.9% after 12 months of tubeless pump therapy. Overall, the number of patients in the A1C ≥9% category was nearly halved, from 40 at baseline to 23 at follow-up. This finding reinforces the benefit of offering other options for insulin delivery to people with type 1 diabetes who are not meeting glycemic goals with their current therapy (
Multiple studies have demonstrated that CSII therapy is associated with improved glycemic outcomes compared with MDI therapy (
Although those using CSII with a tubed pump may not see a benefit in A1C when transitioning to a tubeless pump, it is possible that they could experience benefits in other areas, such as quality of life. Patient satisfaction and quality of life were not assessed in the current analysis; however, a previous study demonstrated that tubeless pump users perceived substantial benefits in quality of life from use of the device (
Weight was stable for patients transitioning from both MDI and CSII. These findings are in line with a recent observational study in two large cohorts of adults with type 1 diabetes from real-world multidisciplinary diabetes centers that found clinically significant reductions in A1C in patients with suboptimal glycemic control without a negative impact on weight 1 year after transitioning from MDI to CSII (
Strengths of the current study include the multisite, real-world setting, which allowed for the collection of data from patients using the tubeless insulin pump in a routine clinical setting across multiple diabetes centers. Additionally, an advantage of the current study was the follow-up period of 12 months, which allowed for assessment of the durability of changes in glycemic control following tubeless insulin pump initiation beyond the initial transition period.
Principal study limitations relate to selection bias resulting from the retrospective nature of the analysis, lack of a control group, exclusion of patients who did not have 12-month A1C data, and lack of data regarding patient satisfaction and quality of life. Data were not available for most participants on modality of glucose measurement (continuous glucose monitor [CGM] or blood glucose meter), so we were not able to account for CGM use as a factor that may affect glycemic outcomes. Although the number of prior MDI users was substantial, there was a smaller population of prior CSII users, which may have affected our ability to assess significant changes in this population. Furthermore, we were unable to assess the influence of prior therapy among those with a baseline A1C ≥9% because there were not sufficient prior CSII users with high baseline A1C within the study population (
Additional work is needed to better understand the effects on glycemic control of initiating tubeless pump therapy in those previously treated with CSII with a tubed pump. Future studies may also evaluate additional outcomes such as total daily insulin use, frequency of acute complications, quality of life measures, and patient preference for the tubeless insulin pump versus prior therapy.
This multisite, retrospective study of adults with type 1 diabetes electing to transition to the tubeless insulin pump demonstrated improved glycemic control over a 12-month follow-up period compared with prior therapy. The subgroup transitioning from MDI had a significant improvement in A1C, whereas the smaller subgroup transitioning from CSII with a tubed pump maintained comparable glycemic control between baseline and follow-up. The greatest decrease was noted in the subgroup with baseline A1C ≥9%, whereas A1C remained stable between baseline and follow-up in the subgroup with baseline A1C <9%. 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 authors thank the study participants and dedicated staff at the participating research centers, including Lisa Volkening, Nisha Naik, Zijing Guo, and Luisa Masclans of the Joslin Diabetes Center; Heather Remtema of the Henry Ford Health System; and staff at Atlanta Diabetes Associates. We appreciate the efforts of the research and development and clinical teams at Insulet Corp. We also thank Clarity Pharma Research for its role in conducting the study.
This research was sponsored by Insulet Corp. S.N.M. was supported by National Institutes of Health grant P30DK036836. B.B. was supported by research and grant support from his employer, Atlanta Diabetes Associates.
D.K. is a speaker for Abbott, AstraZeneca, Boehringer Ingelheim, Dexcom, Insulet Corp., Lilly, Novo Nordisk, and Xeris; is a consultant for Abbott, Dexcom, Sanofi, and Xeris; and has done research with Abbott, Dexcom, Novo Nordisk, and Sanofi. B.B. is a stockholder of Aseko; a consultant for Adocia, Astra Zeneca, Janssen, Lilly, Mannkind, Medtronic, Novo Nordisk, and Sanofi; and a speaker for Astra Zeneca, Lilly/Boehringer Ingelheim, Janssen, Medtronic, Novo Nordisk, Sanofi, and Senseonics. J.E.L. and K.D. were employees of Insulet Corp. when this work was performed. L.M.H., B.D., and T.T.L. are full-time employees of Insulet Corp. L.M.L. is a consultant for AstraZeneca, Boehringer Ingelheim, Convatec, Dexcom, Eli Lilly, Insulet Corp., Insulogic, Janssen, Novo Nordisk, Roche, and Sanofi. No other potential conflicts of interest relevant to this article were reported.
S.N.M., J.E.L., B.D., T.T.L., and L.M.L. contributed to the conception or design of the work. S.N.M., L.J.T., D.K., B.B., B.D., and L.M.L. contributed to the acquisition of data. S.N.M., B.B., J.E.L., L.M.H., K.D., T.T.L., and L.M.L. contributed to the analysis of data. S.N.M., L.J.T., D.K., B.B., J.E.L., L.M.H., K.D., T.T.L., and L.M.L. contributed to the interpretation of data. S.N.M., L.M.H., K.D., and J.E.L. drafted the manuscript, and all authors critically revised the manuscript. T.T.L. is the guarantor of this work and, as such, had full access to all the data in the study and takes responsibility for the integrity of the data and the accuracy of the data analysis.
Data from this manuscript were presented in part at the American Diabetes Association’s 79th Scientific Sessions in San Francisco, CA, 7–11 June 2019.
Author J.E.L. is currently affiliated with Onduo, Newton, MA.
Author K.D. is currently affiliated with Takeda, Lexington, MA.