Challenges of Long-Distance Air Travel With Type 1 Diabetes

Although long-distance air travel across multiple time zones presents many potential difficulties in general, insulin-treated individuals face numerous additional challenges related to this type of travel. They must adjust insulin dosage based on time zone, for example, and they may need to consider the effects of altitude on blood glucose levels.¹ Despite these issues, there is a lack of adequate, easily accessible resources to guide patients in such planning.

Noting the dearth of data on this topic, Pinsker et al explored the real-life experiences of adults with type 1 diabetes (T1D) who have traveled long distance (defined here as travel across 5 or more time zones).² They recruited 503 members of the T1D Exchange online patient community, Glu, each of whom completed a 45-question online survey about their long-distance flying experiences.

The results were as follows.

• 71% of respondents had traveled long-distance by air in the last 5 years.
• Among those using continuous subcutaneous insulin infusion therapy, with or without a continuous glucose monitor, the primary travel-related fear was “losing supplies.”
• Among noncontinuous subcutaneous insulin infusion users, “unstable blood glucose (highs and lows)” was cited as a main concern.
• Among those who had traveled overseas, more hypoglycemia and/or hyperglycemia was reported to have occurred during travel.
• Issues pertaining to diabetes management led 9% of respondents to avoid overseas travel altogether.
• 22% of participants had run out of insulin during a trip.
• 37% of participants indicated that available sources of information do not adequately address self-management needs for insulin-treated patients during travel.

Although participants’ long-distance travel experiences varied, the “commonalities of lacking emergency abroad protocols, encountering security issues, and struggling to maintain regulated basal insulin rates across new time zones presented serious concerns,” the authors wrote. These results align with those of previous surveys, in which insulin-treated patients experienced difficulty managing glucose during travel.^3,4 “Thus, a better understanding of the fears, difficulties, and needs of patients traveling with T1D will allow for the development of individualized and practical resources,” the authors concluded.

For additional insight and takeaways for clinicians, Endocrinology Advisor interviewed study coauthor David Kerr, MD, FRCPE, the director of research and innovation at the Sansum Diabetes Research Institute in Santa Barbara, California; and David C. Klonoff, MD, FACP, FRCPE, Fellow AIMBE, a clinical professor of medicine at the University of California, San Francisco, and medical director of the Diabetes Research Institute of Mills-Peninsula Medical Center in San Mateo.

Endocrinology Advisor: What are the top takeaways from this study, and how do the findings align with your experience with patients with T1D?

David Kerr, MD, FRCPE: Deciding on dosing and timing of diabetes medications immediately before, during, and after a flight is difficult; advice is variable and not personal; and making a mistake can have catastrophic medical consequences for the individual, their families, and fellow travelers.

For people with diabetes who are planning travel, consideration needs to be given to every stage of a journey, starting with deciding when to travel, what to pack, and purchasing travel insurance, and then to passing through airport security and anticipating consequences of late or delayed flights, through assessing the impact of crossing multiple times zones and jet lag.

More than half of travelers with diabetes report difficulties in managing their blood sugar levels during their journey or in the first 24 hours after arriving at their destination.² Diabetes also contributes directly to medical emergencies. In our recent study, 70% of participants had flown long-distance, but sadly, almost 1 in 10 had avoided international travel altogether because of their worries about travel and diabetes.²

A simple trip to and from an airport carries risk for people with diabetes. Being late arriving at an airport or at the destination hotel dramatically increases the risk for hypoglycemia, putting adults and children at risk for serious complications, including loss of consciousness, collapse, seizure, coma, and rarely death, as well as missing their journey altogether.

David C. Klonoff, MD, FACP, FRCPE: Long-distance air travel for people with diabetes is challenging, and often results in hypoglycemia and/or hyperglycemia. These people face many difficulties including, in many cases, navigating through airport security with paraphernalia that can require special scrutiny, losing supplies that cannot easily be replaced, lacking access to healthy food choices, needing a place to exercise in an unfamiliar location, and experiencing stresses that can greatly affect glucose levels. My experiences with my own patients are similar to those reported by the respondents in the article’s survey.

Endocrinology Advisor: What are the implications for clinicians; for example, how might they help address some of these issues with individual patients?

Dr Kerr: Clinicians need access to better tools to personalize the advice they give to people with diabetes. A journey begins and ends at home, but the clinician needs to consider all aspects including the impact of time zones on the timing and dose of insulin and other medications. They also need to think about the “what-if” scenarios (eg, the impact of delayed flights and lost luggage containing diabetes supplies), and how to access timely and appropriate care at the destination.

Dr Klonoff: Clinicians need more sources of information to convey to their traveling patients with diabetes. An example of a problem that travelers with diabetes face if they use basal insulin is when to take their first dose when they are traveling east to west or vice versa across time zones. Because of the time zone changes, instead of using this insulin every 24 hours, it might be necessary to administer their first dose of basal insulin while traveling at an inconvenient time of day to maintain the 24-hour dosing interval. 

Otherwise, if they use the dose at the usual time on the clock in a new time zone, this dose will either stack up on a previous dose (if traveling west to east), or else there will be a gap in coverage between doses (if traveling east to west). Dose stacking tends to cause hypoglycemia, and dosing gaps tend to cause hyperglycemia. Traveling north to south within the same time zone does not expose a patient to these changes in basal insulin activity.

Endocrinology Advisor: What should be next steps in this area, in terms of research or otherwise?

Dr Kerr: We are planning research whereby we will fly insulin-treated individuals long-haul to capture prospective data to allow us to create algorithms for future travelers.

Dr Klonoff: There has been little research on how long-distance travel across time zones affects the physiology of patients with diabetes and whether the effects of travel lead to any preventable inflammatory changes. Patients need an accurate source of information. The medical community has not reached a published consensus on rules for adjusting insulin therapy during air travel, and such policies are needed. The team that wrote this Pinkser et al article² has developed an excellent resource website for travelers with answers to frequently asked questions.

References

1. Neithercott T. 35 top tips for travel with diabetes. Diabetes Forecast. 2013;66:40-43.
2. Pinsker JE, Schoenberg BE, Garey C, Runion A, Larez A, Kerr D. Perspectives on long-distance air travel with type 1 diabetes. Diabetes Technol Ther. 2017;19(12):744-748.
3. Driessen SO, Cobelens FG, Ligthelm RJ. Travel-related morbidity in travelers with insulin-dependent diabetes mellitus. J Travel Med. 1999;6(1):12-15.
4. Burnett JC. Long- and short-haul travel by air: issues for people with diabetes on insulin. J Travel Med. 2006;13(5):255-260.