Risk factors for reflex syncope in the British Army

Area of Science:

• Military Medicine
• Physiology
• Public Health

Background:

• Reflex syncope incidence is higher in UK Armed Forces, particularly among soldiers performing State Ceremonial and Public Duties (SCPD).
• Previous studies have not fully investigated individual susceptibility factors for syncope in this specific military population.

Purpose of the Study:

• To investigate individual susceptibility factors for reflex syncope in soldiers who regularly perform SCPD.
• To identify triggers and current management strategies for syncope in this cohort.

Main Methods:

• Retrospective cohort study of 200 soldiers performing SCPD.
• Data collected via questionnaires on medical history and fainting episodes, and electronic healthcare records.
• Participants categorized into syncope (n=80) and control (n=120) groups.

Main Results:

• Orthostasis (61%) and heat (35%) were primary triggers for syncope.
• Migraine/headache history increased syncope risk (OR 8.880); antihistamine use, non-white ethnicity, and male sex were protective.
• Common soldier interventions included hydration (59%) and 'toe wiggling' (55%); 30% of those who fainted did not seek medical attention.

Conclusions:

• Orthostatic-mediated reflex syncope, exacerbated by heat, is prevalent in SCPD soldiers.
• Soldiers' current syncope avoidance methods lack evidence-based support.
• Findings can inform targeted interventions to prevent syncope in service personnel during SCPD.