Effects of Exercise and Sleep Deprivation on Reaction Severity During Oral Peanut Challenge: A Randomized Controlled Trial.

Background: The severity of allergic reactions to foods can vary markedly. Little is known of variations in reaction severity within or between individuals or the effects of cofactors.

Objective: We examined the effects of sleep deprivation and exercise and repeat challenges on the severity and patterns of allergic reactions to peanut.

Methods: In a randomized crossover study, adults with peanut allergy underwent 3 open peanut challenges in random order: with exercise after each dose, with sleep deprivation preceding challenge, and with no intervention. The primary outcome was eliciting dose, reported elsewhere. Reaction severity was a secondary outcome, evaluated using a weighted log-transformed numerical severity score. Analyses estimated the difference in severity between nonintervention challenge and challenges with exercise or sleep deprivation, adjusting for challenge order and using the highest dose tolerated by each individual across all their challenges. Symptom pattern reproducibility was assessed by comparing symptom sequences using pairwise sequence alignment to obtain a percentage match in symptom pattern.

Results: Eighty-one participants (mean age 25 y) completed at least 1 postbaseline challenge. Sleep deprivation, but not exercise, significantly increased severity score by 48% (95% CI 12%-84%; P = .009) compared with no intervention. A 38% increase in severity was observed between the first and the last postbaseline challenge (95% CI 1%-75%; P = .044). The average pairwise match of symptoms within individuals was 82.4% and across individuals was 78.3%.

Conclusions: A novel severity score demonstrates that sleep deprivation and repeated challenges increase reaction severity. Understanding factors affecting severity is essential for effective risk management. We also show that symptom patterns in repeat peanut challenges are similar within and between individuals.