Altered endothelial function in high-performance military fighter pilots

High-performance fighter pilots are routinely subjected to extreme mechanical and physiological stressors, including exposure to high +Gz accelerations that may impact vascular health. In this short report, we evaluated endothelial function in 20 Eurofighter Typhoon (F-2000A) pilots and 19 matched control pilots flying non-high-G aircraft (KC-767A). Flow-mediated dilation (FMD) of the brachial artery was measured before and after flight sorties to assess vascular response. FMD values were lower after flight compared to pre-flight measurements, reflecting a significant main effect of Time across the entire cohort (p < 0.05). Within-group analyses revealed a larger absolute reduction in FMD in F-2000A pilots (median 10.02% to 6.45%) compared with controls (9.40% to 8.80%). However, the absence of a significant Time × Group interaction indicates that this response was not statistically different between pilot groups. Additionally, F-2000A pilots exhibited smaller arterial diameters at rest and a significant post-flight increase in baseline vessel caliber (3.81 mm to 4.13 mm; p < 0.001), suggesting a transient vasodilatory response potentially related to thermal or hemodynamic stress. These findings suggest an acute endothelial response to the high-performance flight environment. This study underscores the need for continued cardiovascular surveillance in high-performance aviators and supports further investigation of FMD as a non-invasive marker of vascular function within structured aeromedical follow-up programs.