Biography: Aldasouqi is professor of medicine and chief of the endocrinology division at Michigan State University College of Human Medicine in East Lansing.
October 29, 2018
4 min read

Blog: As daylight savings time ends, caution for users of insulin pumps

Biography: Aldasouqi is professor of medicine and chief of the endocrinology division at Michigan State University College of Human Medicine in East Lansing.
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The fall’s daylight-saving time change will happen this weekend, in the early morning of Sunday November 4.

Every spring and fall, I have been posting about the time change that occurs twice a year, in early March and early November, when the clock is moved 1 hour forward or backward, respectively.

To briefly reiterate the health-related complications of daylight savings time, one major concern is the increased risk for heart attacks on the Monday following the spring daylight savings time change. This is believed to be related to the loss of sleep and the earlier start of the day.

Another major concern is related to an IT glitch in to insulin pumps, a glitch that has not been, so far, adequately emphasized in the literature or in guidelines by diabetes and other health organizations. Insulin pumps are not equipped to automatically adjust the (offline) built-in internal clocks of the pumps to daylight savings time changes. Neither are pumps equipped with GPS or other central mechanisms that would enable pumps to adjust the time settings automatically. The glitch may potentially result in errors in insulin dosing in patients with diabetes.

This is a call to all patients who use insulin pumps — and their loved ones and their clinicians — to make sure that the insulin pump’s time setting is adjusted to the correct time for this fall’s daylight savings time change this upcoming weekend.

Only the states of Hawaii and Arizona (except for the northeastern region of the state) do not use daylight savings time. Indiana only recently adopted daylight savings time. In my own state of Michigan, some legislators tried to abandon the practice, but their bills failed twice in recent years.

On a related issue, the talk about daylight savings time brings up the topic of a.m./p.m. time settings in insulin pump clocks. Similar to daylight savings time adjustment, the a.m./p.m. times settings need to be adjusted manually by patients. If set up incorrectly, there will be a potential risk of major errors in insulin doses, hence the advice to all patients using insulin pumps to always make sure that the a.m./p.m. time settings are always up-to-date on their pumps.

I will conclude this post with some unusual stories about daylight savings time-related incidents, some of which are funny and some, really hilarious:

The first one is an incident that happened to me over 25 years ago. It was the fall of 1992, when I was an intern at Hurley Hospital in Flint, Michigan. I had just moved to the U.S. the preceding summer, having completed an internal medicine residency at Hamad General Hospital in Doha, Qatar, where daylight savings time change was not used. One Monday morning that fall, I woke up in the morning as usual and arrived at the hospital at 7:30 to start the morning rounds on my patients in preparation for the morning report.

When I left home, around 7:15, while it was somewhat dark, which would be typical for that time of the year, things were unusual on the road. There was no traffic jam on the freeway and inner roads. When I arrived in the hospital, things were different, too. The hospital was quieter than usual. When I arrived at my floor, the night-shift nurses were still working, wrapping up and getting ready to start the sign-out break to the incoming morning shift nurses. Many patients were still asleep. At one point, I thought I was in a dream, or in a Twilight Zone experience.

It was not until I looked at a clock on a wall, which was (mysteriously) 1 hour behind. I said to the clerk, “Madam, that clock is wrong.”

She smiled, and said, “Oh, doctor, I think you may not have noticed that the time changed last night.”

Another story is one related to glitches in a.m./p.m. time settings. Recently, one colleague came late to work in the morning. Reason: The alarm clock did not go off in the morning. The colleague had recently moved to a new place, and upon reconnecting the alarm’s power cable and resetting the alarm, the colleague flipped the a.m./p.m. settings by mistake. The alarm would now go off at 5 p.m. rather than 5 a.m.

Finally, a few years ago, a reporter from a local Lansing, Michigan, TV station interviewed me about the issue of daylight savings time-related glitches in insulin pumps as we were approaching the spring 2016 time change.

I was surprised when the interview aired during the 10 p.m. evening newscast. The reporter told me about two state legislators who each introduced bills to eliminate the daylight savings time practice in Michigan. Part of the transcript read as follows:

“Aldasouqi says patients have to be vigilant about setting the clock on their pumps in order to get the right amount of insulin at the right time. He says he's also read studies that say there are more heart attacks the Monday after the time change. That's why Aldasouqi supports Michigan State Representatives Pete Lucido (R-Shelby Township) and Jeff Irwin (D-Ann Arbor) who each introduced bills to get rid of daylight saving time in the state.”

I laughed when I saw the blend of medicine and politics. I do not like political discussions, but this was a positive one. While the two bills did not pass, I still wish they did. In fact, another attempt by other legislators was tried earlier this year in Michigan’s legislature and also did not pass. I wish Michigan would eliminate daylight savings time, like Hawaii and Arizona. I hate the long summer days. But, I guess that is just me.

I would like to conclude this post by calling upon all clinicians: When you see patients with insulin pumps, please look at the pump’s time on the display and make sure it is current. To all patients using insulin pumps: Please always make sure that the hours and minutes as well as a.m./p.m. time settings on the pump’s time display are always current. This is an important safety precaution.