What Researchers Did
Researchers investigated short- and long-term cortisol responses in 32 Navy divers exposed to one of three thermoneutral conditions (air immersion, dry hyperbaric oxygen, or oxygen immersion) for six hours daily over five consecutive days.
What They Found
Serum cortisol concentrations measured before and after each dive showed no significant difference in change across the three experimental groups (air: 3.63 ± 5.56 ug/dL; dry: 4.91 ± 3.68 ug/dL; oxygen: 3.50 ± 3.48 ug/dL; p > 0.05). No differences were observed in pre- or post-dive cortisol levels across the five dive days for any condition, indicating that these exposures do not abnormally alter cortisol concentrations.
What This Means for Canadian Patients
For Canadian patients undergoing hyperbaric oxygen therapy or water immersion for medical reasons, these findings suggest that such exposures, under controlled thermoneutral conditions, may not significantly disrupt their body's cortisol regulation. This could potentially reduce concerns about stress-related hormonal changes during specific therapeutic or occupational exposures.
Canadian Relevance
This study has no direct Canadian connection as it was not conducted in Canada, nor did it involve Canadian participants or institutions.
Study Limitations
The study's findings are limited to healthy Navy divers under controlled, thermoneutral conditions, which may not be generalizable to other populations or less ideal environments.