Autonomic dysfunction and gastroparesis in Gulf War veterans

Area of Science:

• Gastroenterology
• Autonomic Neuroscience
• Military Medicine

Background:

• Over 25% of Gulf War veterans develop chronic gastrointestinal (GI) symptoms post-deployment.
• The etiology of these GI symptoms in veterans remains largely unknown.
• Chronic GI issues include nausea, vomiting, postprandial abdominal pain, and bloating.

Purpose of the Study:

• To determine the prevalence of delayed gastric emptying in Gulf War (GW) veterans with chronic GI symptoms.
• To investigate the association between delayed gastric emptying and autonomic dysfunction in these veterans.
• To provide insights into the pathophysiology of GI disorders in deployed service members.

Main Methods:

• Prospective study of 35 GW veterans with chronic GI symptoms and 15 asymptomatic controls.
• Autonomic function assessed using 5 standardized cardiovascular tests, with a composite score >1.5 indicating dysfunction.
• Gastric emptying evaluated using a standardized solid-phase test; >50% retention at 100 minutes considered abnormal.

Main Results:

• Symptomatic veterans showed significantly higher composite autonomic scores (3.7 vs. 1.3, p<0.01) compared to controls.
• Mean solid-phase gastric retention was markedly higher in symptomatic veterans (72.6% vs. 24.6%, p<0.001).
• Autonomic dysfunction was positively correlated with the severity of delayed gastric emptying.

Conclusions:

• Autonomic dysfunction and delayed gastric emptying are common in GW veterans experiencing chronic GI symptoms.
• Autonomic dysfunction may be the underlying cause of GI symptoms such as nausea, vomiting, and bloating.
• Findings are crucial for understanding and managing GI disorders in current and future deployed military personnel.