Insulin Pump Therapy in T2DM: A Viable Option?

Insulin pumps have been used for decades to treat patients with type 1 diabetes (T1DM). Are they also a good idea for those with type 2 diabetes (T2DM)? Roughly 30% of people with T2DM may be unable to achieve adequate glycemic control even after intensifying insulin therapy.¹ Intensifying insulin also increases the risk of hypoglycemia and weight gain. 

Results of past studies comparing pumps to multiple daily injections of insulin have been inconsistent. Some studies have suggested no difference between the two, while others have suggested improved glycemic control with pump therapy.

A recent industry-sponsored study addresses this issue.² The study was designed and sponsored by Medtronic, the maker of the insulin pump used in the study.  Medtronic statisticians analyzed the data, while the authors were either direct employees of Medtronic or had served in advisory roles or as clinical investigators for the company.

The multinational randomized-controlled open-label study was called “OpT2mise” and ran from December 2010 to February 2014.  It was conducted at 36 clinical facilities in Canada, Europe, Israel, South Africa, and the United States.  

Results (Table) suggested that delivering insulin by pump resulted in better glycemic control than by multiple daily injections (MDI). Moreover, participants who used the pump also needed less insulin.

“The OpT2mise study demonstrates that pump therapy is a valuable option for treating patients with type 2 diabetes and uncontrolled [baseline] hyperglycemia despite receiving a high-dose insulin regimen,” commented first author Yves Reznik, MD, Professor at the University of Caen Côte de Nacre Regional Hospital Center in Caen France.

“At baseline, the mean dose was around a hundred units per day with at least 3 injections per day of rapid-acting and slow-acting insulin analogues, which is a regimen considered to be the gold standard for intensified insulin therapy,” Reznik added.

Key elements of the study design:

  - Insulin dose optimization: 2-month run-in, insulin regimens intensified using long-acting  (glargine or detemir) and rapid-acting (lispro, aspart, or glulisine) analogues

  - Participants whose A1c remained between 8.0 and 12.0% after insulin optimization were randomized to pump treatment* or mutiple daily injections

  - Pump group (n=168): Pumps delivered half of total daily dose via basal flow

  - MDI group (n=163): Continued titration of insulin to target

  - Bolus dosing: Left to investigator’s judgment in both groups

  - Patients, investigators not masked to treatment

  - Continous glucose monitoring, masked

Table. Key Results

CI = cognitive impairment (Montreal Cognitive Assessment Test); ^ahyperglycemia or ketosis without acidosis leading to hospitalization; ^bone case severe hypoglycemia in MDI group

“Importantly, even mild cognitive limitations do not preclude pump effectiveness,” Reznik concluded, “Pump may obviate several limitations such as the burden of dose tracking and scheduling, or insulin injection omissions.”

Pratik Choudhary, MD, senior lecturer in the Diabetes Research Group at King’s College in London, provided an accompanying editorial.³  Choudhary, who has received compensation and served on the advisory board for Medtronic, pointed out that patients with inadequate glycemic control despite escalating doses of insulin basically have three choices: GLP-1 receptor agonists, bariatric surgery, or continued insulin dose escalation. All three options have problems, according to Choudhary. Insulin absorption and bioavailability are lower at basal insulin doses above 60 units per day.  Many patients have trouble tolerating the gastrointestinal side effects of GLP-1 receptor agonists. Finally, not all patients are willing or able to undergo bariatric surgery.

“OpT2mise provides a compelling case for the clinical effectiveness of insulin pump treatment in type 2 diabetes, suggesting that it can help improve glycemic control in this difficult to treat group of patients who are unable to achieve glucose control despite increasing doses of insulin,” Choudhary commented. “However,” he cautions, “cost effectiveness of pumps in different healthcare systems will need to be evaluated.”

*Medtronic MiniMed Paradigm Veo system

Disclosures:

Authors Yves Reznik and Ohad Cohen reported being co-investigator on clinical trials for Medtronic, while Cohen received investigator fees for OpT2mise.  Other investigators (Ignacio Conget, Ronnie Aronson), have received fees from Medtronic, while the remainder of the authors (Sarah Runzis, Javier Castaneda, and Scott W-Lee) are Medtronic employees.

Pratik Choudhary has received compensation and served on the advisory board for Medtronic.

References:

• Riddle M, Umpierrez G, DiGenio A, et al.  Contributions of basal and postprandial hyperglycemia over a wide range of A1C levels before and after treatment intensification in type 2 diabetes. Diabetes Care. 2011;34:2508-2514. doi: 10.2337/dc11-0632. 
• Reznik Y, Cohen O, Aronson R, et al. Insulin pump treatment compared with multiple daily injections for treatment of type 2 diabetes (OpT2mise): a randomized open-label controlled trial.  Lancet.  Published online July 3, 2014.
• Choudhary P. Continuous subcutaneous insulin infusion for type 2 diabetes. Lancet.  2014 Jul 2. pii: S0140-6736(14)61098-9. doi: 10.1016/S0140-6736(14)61098-9. [Epub ahead of print] [No abstract available]