Patients who used Medtronic insulin pumps to treat their diabetes went to the hospital 27 percent fewer times over the course of a year compared to diabetics who used multiple daily injections to manage their blood-sugar levels, an analysis of UnitedHealthcare insurance members has found.

The analysis, funded and run by the two Minnesota companies, helps to show that investments in Medtronic's user-run insulin pumps can create "value" by improving patient health and preventing costly hospital admissions down the line.

"This was a first-year analysis. We are excited about what the results show," said Suzanne Winter, vice president of the Americas region for Medtronic's diabetes unit. "We will continue to look at years two through four" of the retrospective study of de-identified patient records.

The project brings together the nation's largest insurer, UnitedHealthcare, based in Minnetonka, and the nation's largest medical device company, Medtronic, which is based in Ireland and run from offices in Fridley. Both companies have been vocal about the need to create "value-based" agreements in health care, in which payments can vary based on whether the intervention works and the patient stays healthy.

The companies said early results from the Medtronic insulin pump study are encouraging, but more data is needed. A spokeswoman for UnitedHealthcare said Tuesday that it can take up to five years to develop comprehensive data on how value-based deals improve quality of care, lower costs and drive down the number of hospitalizations.

UnitedHealthcare was criticized by some in the diabetes community in 2016 after the insurer announced changes in two of its insurance plans intended to steer adult diabetics who use an insulin pump to Medtronic devices, including devices that were included in the study results unveiled Tuesday.

The insurer has said most of its adult patients with pumps were already using Medtronic devices. Some patients and doctors contended that UnitedHealthcare was limiting patient choice by forcing members of the affected plans to go through a special process to get coverage for a pump from any other company.

Medtronic has since opened discussions with other insurance companies about value-based arrangements with its insulin pumps, though they won't necessarily involve an insurer steering patients toward Medtronic pumps.

The first-year data from the UnitedHealthcare study showed lowered costs among the Medtronic pump users, but the companies declined to say Tuesday whether the decrease from reduced hospitalizations and other factors made up for the $5,000 or so upfront cost of insulin pumps, plus the related supplies.

UnitedHealthcare declined to reveal the average per-person costs for each group. Medtronic officials said a "white paper" with more results is likely to be published in the future.

"The first-year results are encouraging, and we will monitor patients using Medtronic pump therapies to ensure we continue to see improved quality of care, fewer hospitalizations, and lower costs," incoming UnitedHealthcare Chief Medical Officer Dr. Peter Pronovost, said in the news release.

The study examined the records of 6,000 people covered by UnitedHealthcare plans who used a Medtronic insulin pump from July 2016 to June 2017, and compared them to a similarly sized cohort of patients who used multiple daily injections of insulin.

Virtually all of the patients in the analysis had Type 1 diabetes, the form of the disease in which patients' bodies don't produce the insulin they need because of an autoimmune disorder. Having blood sugar that is either too high or too low can trigger acute health problems and can lead to hospitalizations for conditions like hypoglycemia and diabetic ketoacidosis.

The analysis examined "preventable" hospitalizations among patients using a variety of Medtronic's older insulin devices, including the MiniMed 630G insulin pump, and compared those results to UnitedHealthcare members who used multiple manual daily injections of insulin. UnitedHealthcare stressed that in addition to the pumps, patients also received comprehensive support services from Medtronic.

Financial details of the agreement between Medtronic and UnitedHealthcare have not been disclosed.

Overall, UnitedHealthcare said it has $65 billion in total payments to physicians and hospitals tied to value-based arrangements, and that figure is expected to grow to $75 billion by 2020.

The one-year results largely omitted the experience of patients using Medtronic's 670G insulin pump, which automates delivery of a base-dosage of insulin using real-time readings from a continuous glucose sensor paired to the system. The 670G was released at the end of the measurement period, and is now a part of the preferred-provider arrangement with UnitedHealthcare.

Based on clinical-trial results from users of the 670G, Medtronic anticipates that future analysis of its pump users covered by UnitedHealthcare will show further improvements in outcomes.