Objective: Hyperglycemia has been shown to induce cognitive changes in processing speed, executive function, attention, and working memory in several laboratory based mental tasks. It has also been identified as the main culprit in diabetes related cognitive decline. Driving is a complex task that requires intricate coordination between cognitive and motor skills and provides information on how acute hyperglycemia may affect people with type 2 diabetes in the real world. This study aims to identify associations between acute hyperglycemia in subjects with normally well controlled type 2 diabetes and measures of driving ability.

Methods: This randomized experimental crossover study selected actively driving subjects with well controlled type 2 diabetes between the ages of 25-45. Subjects were asked to operate a driving simulator (STISIM Drive M100) in two glycemic states: euglycemia and acute hyperglycemia. Subjects were randomized and cross-covered with each session separated by one week to account for any learning effects. Hyperglycemia was induced by asking subjects to withhold their usual diabetes related medications the day before the study.

Results: A total of 12 subjects have completed this study. No significant associations were found in several parameters examining adherence to speed limits, ability to maintain lane position, number of collisions, or ability to follow a lead car. When comparing euglycemic driving to acute hyperglycemic, subjects had a mean speed of 45.1 ± 6.81 vs. 43.4 ± 1.86 (p=0.42), time above speed limit 12.8 ± 15.0 vs. 13.9 ± 7.83 (p= 0.78), standard deviation in lateral position 1.63 ± 0.36 vs. 1.58 ± 0.35 (p=0.79), centerline crossings 3.08 ± 6.01 vs. 2.50 ± 2.11 (p=0.77), modulus car following 0.60 ± 0.31 vs. 0.52 ± 0.32 (p=0.30), and number of collisions 0.50 ± 0.67 vs. 0.17 ± 0.39 (p=0.17).

Conclusion: The current data is inconclusive given the small sample size and merits further exploration with a larger study.


T. Nguyen: None. V.V. Dao: None. J. Timberman: None. S. Davis: None. S. Doroudgar: None. J.H. Shubrook: Advisory Panel; Self; Intarcia Therapeutics, Inc. Consultant; Self; Eli Lilly and Company, Novo Nordisk Inc.


Touro University California

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