Clinical trial NCT01913925: Effect of Tyrosine Supplementation on Cognitive Performance and Mood During Military Stress
Official title: Effect of Tyrosine Supplementation on Cognitive Performance and Mood During Military Stress
Study type: INTERVENTIONAL
Overall status: COMPLETED
Phase: NA
Conditions: Reaction to Severe Stress, Unspecified
Lead sponsor: United States Army Research Institute of Environmental Medicine
Sponsor class: FED
First posted: 2013-08-01
Enrollment: 80
Sex: ALL
Minimum age (years): 18
Maximum age (years): 39
Standard ages: ADULT
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: PARALLEL
Primary purpose: OTHER

Brief summary: The objective of this research is to determine if tyrosine, an amino acid found in protein-containing foods, will mitigate the cognitive deficits and adverse effects on behavior and mood produced by exposure to military stress. This study was conducted at the US Navy Survive, Evade, Resist, Escape (SERE) school at Brunswick, Maine (ME).

Tyrosine is the dietary precursor of the catecholamine norepinephrine, a key brain neurotransmitter that is critical for the central nervous system (CNS) response to various types of acute stress. Psychological stress increases catecholamine turnover in the brain, increasing the requirement for tyrosine to support synthesis of norepinephrine. Animal and human studies have shown that tyrosine supplementation can produce beneficial effects on cognitive and physiological functions during exposure to a variety of acute stressors.

This project will determine if volunteers treated with supplemental tyrosine during stressful phases of SERE training experience less degradation in cognitive performance and mood than volunteers treated with placebo. Tyrosine or placebo will be administered in a specially developed food bar provided to volunteers. The bar is part of a prototype of ration-component designed for use during assault operations. A between-subjects, double blind experimental design will be employed. Tyrosine, an amino acid found in most protein-containing foods, has been tested in hundreds of volunteers without adverse effects.

Approximately 100 volunteers will be recruited from several SERE classes to ensure up to 80 volunteers complete the study. They will be tested during several portions of SERE. A comprehensive but brief battery of cognitive tests, as well as saliva samples, and heart rate data will be collected in a manner that does not interfere with ongoing training.

Hypotheses:

1. Exposure to the stressors of SERE school will adversely impact cognitive performance and mood of volunteers.
2. The adverse effects of psychological stress on cognitive performance and mood during SERE school will be reduced when volunteers are given supplemental tyrosine compared to placebo treatment.


Eligibility criteria: Inclusion Criteria:

* Active duty military enrolled in the US Navy SERE School, Brunswick, ME.
* Fluent in English (non-native English speakers can be enrolled).

Exclusion Criteria:

* None.

\[All volunteers enrolled in SERE school require a medical clearance. No additional inclusion or exclusion criteria are necessary.\]

Primary outcomes:
measure: change from baseline cognitive function compared to cognitive function as measured following treatment administration
timeFrame: baseline and final week of training (approximately 1 week later)
Secondary outcomes:
Other outcomes:
Locations:
city: Brunswick
country: United States
facility: US Navy SERE School
state: Maine
Study officials:
affiliation: United States Army Research Institute of Environmental Medicine
name: Harris R. Lieberman, PhD
role: PRINCIPAL_INVESTIGATOR
References: