Clinical, biomarker, and research tests among US government personnel and their family members involved in anomalous health incidents

Abstract

Overview

Since 2015, US government personnel and their family members have reported a constellation of symptoms—including dizziness, pain, visual issues, and cognitive dysfunction—after encounters involving intrusive sounds and head pressure. These occurrences have been labeled by the US government as anomalous health incidents (AHIs).

Study Design and Objectives

• Objective: To evaluate whether those reporting AHIs differ from control participants regarding clinical, biomarker, and research assessments.
• Setting: National Institutes of Health Clinical Center (June 2018 - July 2022).
• Participants: 86 US government staff and family members with AHIs from various locations (Cuba, Austria, China, etc.) and 30 matched government control participants.

Findings

• No significant differences detected between AHI and control groups on most auditory, vestibular, cognitive, or visual function tests, or in blood biomarker levels.
• Participants with AHIs displayed:
  • Significantly worse self-reported and objective measures of balance
  • Increased symptoms of fatigue, posttraumatic stress disorder, and depression
  • Functional neurological disorders observed in 24 AHI participants (28%)
• These findings held regardless of the risk characteristics or geographic location tied to the AHIs.

Conclusion

This exploratory study did not find significant differences on most clinical, research, and biomarker measures when comparing AHI and control participants, except for issues related to balance, fatigue, depression, and posttraumatic stress, with a notable subset developing functional neurological disorders. The study did not reproduce findings from previous research, potentially due to differences in sample populations and assessment timing.