Insulin Pump Glitches: A Call to End Daylight Saving Time?

Katie Sullivan, DNP, FNP-C, is publicizing her own challenge with updating an insulin pump as part of an effort to bring an end to the biannual seasonal clock changes in the United States.

On March 10, 2024, Sullivan, who works in the Endocrinology Clinic, Michigan State University, East Lansing, Michigan, mistakenly reversed the AM and PM settings while adjusting her own insulin pump. Sullivan, who has type 1 diabetes, noticed several hours later that her blood glucose levels had become higher than usual and was surprised to see her pump showed sleep mode during the day.

She was able to address this glitch before going to sleep and thus “escaped a potential occurrence of nocturnal hypoglycemia,” wrote Sullivan and her colleague, Saleh Aldasouqi, MD, in a September commentary in the journal Clinical Diabetes.

The risk of daylight saving time (DST) changes for people with insulin pumps is well known. Aldasouqi himself raised it in a 2014 article in the Journal of Diabetes Science and Technology.

Medtronic Inc., the leading maker of insulin pumps, told Medscape Medical News in an email that it intends for future devices to automate DST changes. The company did not provide any further details on when such changes would happen.

For now, Medtronic and other makers of insulin pumps join in twice-a-year efforts to remind people they need to update their devices to adjust for DST changes. They will need to gear up these outreach campaigns, which include social media posts, again ahead of the end of DST on November 3, when clocks shift back an hour. Diabetes clinics and hospitals also send notes to patients.

Even so, people will fail to make this change or to do it correctly.

“Despite our efforts to educate our patients about DST glitches, we have detected incorrect time settings in some of our patients’ insulin pumps after the DST changes in the fall and spring and occasional cases of incorrect insulin dosing, resulting in hyperglycemia or hypoglycemia,” Sullivan and Aldasouqi wrote in their article.

The US Food and Drug Administration (FDA) database of injuries and mishaps with devices contains many reports about patients not adjusting their insulin pumps for DST.

Known as Manufacturer and User Facility Device Experience (MAUDE), this database does not provide identifying details about the patients. Instead, the reports contain only a few lines describing what happened. In many cases, people were able to easily resolve their temporary glycemic issues and then set their devices to the correct time.

But some of the MAUDE reports tell of more severe consequences, with people ending up in emergency rooms because they did not adjust their insulin pumps for DST.

Among these is a report about a November 2022 incident, where a patient suffered due to what appeared to be inaccurate continuous glucose monitor readings, combined with the effects of an insulin pump that had not been updated for a DST change.

Although that patient’s mother was available to assist and the patient consumed three dextrose candies, the patient still reportedly lost consciousness and experienced tremors. That led to hospitalization, where the patient was treated with intravenous saline, intravenous insulin, saline fluids, and insulin fluids. The patient left the hospital with “the issue resolved and no permanent damage” but then switched to another method of insulin therapy, the MAUDE report said.

It’s unclear how often DST changes lead to problems with insulin pumps, reflecting difficulties in tracking flaws and glitches in medical devices, Madris Kinard, the chief executive officer and founder of Device Events, told Medscape Medical News.

The FDA relies heavily on passive surveillance, gathering MAUDE reports submitted by companies, clinicians, and patients. That means many cases likely are missed, said Kinard who earlier worked as an analyst at the FDA, updating processes and systems to help identify risky devices.

For example, Sullivan told Medscape Medical News she had not filed a report for her incident with the insulin pump.

Permanent Standard Time?

Many clinicians, including Aldasouqi and Sullivan, argue a better solution to these challenges would be to end DST.

In their Clinical Diabetes article, they also cited other health risks associated with clock changes such as fatigue, headache, and loss of attention and alertness that can result in injuries.

But a permanent time change is a “politically charged issue, and it continues to be debated nationally and at the state level,” they wrote.

At least 30 states also considered measures this year related to DST, according to the National Conference of State Legislatures. A pending Senate bill intended to make DST permanent has the support of 8 Democrats and 11 Republicans, including Sen. Tommy Tuberville (R-Ala).

“It’s amazing how many phone calls we get over this one topic. People across America agree that changing our clocks back and forth twice a year really makes no sense,” Tuberville said last year on the Senate floor. “People call and say they’re just sick of it.”

These federal and state efforts have stalled to date on the key question of whether to make either standard time or DST permanent, the National Conference of State Legislatures noted. A shift to permanent DST might have benefits for some agricultural and recreational industries, but many physicians say it would be bad for people’s health.

The American Academy of Sleep Medicine (AASM) argues strongly for moving to permanent standard time. In a position statement published in the Journal of Clinical Sleep Medicine, the group said the acute transitions from standard time to DST pose harms, citing research indicating increased risks for adverse cardiovascular events, mood disorders, and motor vehicle crashes.

The solution is to end shifts in time and opt for standard time, which best aligns with the human biological clock, AASM said.

AASM noted that there already was a failed experiment in the United States with a shift to permanent DST. Congress established this in response to the 1973 OPEC oil embargo, expecting that allowing more evening hours with light would lead to energy savings. That didn’t pay off in the expected reduction in energy and the policy was highly unpopular, especially in rural areas, AASM said.

“After a single winter, the policy was reversed by an overwhelming congressional majority,” wrote Muhammad Adeel Rishi, MD, and other authors of the statement. “The unpopularity of the act was likely because despite greater evening light, the policy resulted in a greater proportion of days that required waking up on dark mornings, particularly in the winter.”

Karin G. Johnson, MD, a professor of neurology at the UMass Chan School of Medicine, Worcester, Massachusetts, told Medscape Medical News that a shift to permanent DST would rob many people of the signals their bodies need for sleep.

“Sunrises and sunsets are later and that creates a desire for our body to stay up later and have more trouble getting up in the morning,” Johnson said. “You’re all but making it impossible for certain segments of the population to get enough sleep” with permanent DST.

Johnson, Sullivan, and Aldasouqi had no relevant financial disclosures.

Kerry Dooley Young is a freelance journalist based in Washington, DC. Follow her on LinkedIn and Threads.