Sleep deprivation, repeated exposure increase symptom severity in oral peanut challenges

Sleep deprivation and repeat challenges, but not exercise, increased the severity of allergic reactions during peanut oral food challenges, according to a study published in The Journal of Allergy and Clinical Immunology: In Practice.

These results could help physicians advise patients about their future reactions, Shelley Dua, PhD, a consultant in the department of allergy at Cambridge University Hospitals, Cambridge, U.K., and colleagues wrote.

The multicenter, randomized crossover study involved 81 adults aged 18 to 45 years (mean age, 25 years) with peanut allergy who completed a baseline OFC for peanut allergy and then at least one of three open challenges. These included an exercise challenge (n = 73), which comprised 10-minute sessions on a static bike at 85% maximum exercise capacity 5 minutes after each dose; a sleep deprivation challenge (n = 71), during which participants slept for a maximum of 2 hours the night before the OFC and were then kept awake until the challenge; and the nonintervention challenge (n = 71), which followed the same methodology as the baseline OFC.

Researchers then compared the severity of reactions after each these challenges, classified by the number of involved organ systems and whether there was cardiovascular, neurological, bronchial or laryngeal involvement.

Researchers documented 56 anaphylactic reactions, with 35% happening during the baseline challenge, 20% during the exercise challenge, 20% during the sleep deprivation challenge and 25% during the nonintervention challenge.

Sleep deprivation led to a 48% (95% CI, 12-84) increase in symptom severity during OFC compared with the nonintervention challenge. Specifically, cutaneous symptom severity increased by 41% (95% CI, 8-74), throat symptom severity increased by 53% (95% CI, 17-88) and gastrointestinal symptom severity increased by 46% (95% CI, 8-84).

There also was an association between exercise and a 28% (95% CI, –9 to 66) increase in symptom severity, although the researchers found it was not significant at a 5% level. However, exercise did cause a 63% (95% CI, 25-100) increase in respiratory symptom severity.

Additionally, the researchers found an increase in symptom severity with each subsequent visit after the baseline visit. Symptom severity was 38% (95% CI, 1-75) higher during the third visit compared with the first visit. By repeating the model with a linear trend, the researchers found a 19% (95% CI, 1-38) increase with each visit.

With data available from 30 participants, the researchers found significant increases in Ara h 2 IgG4 with each visit, with a 29% (95% CI, 6-51) increase during the second visit, a 30% (95% CI, 8-51) increase during the third visit and a 49% (95% CI, 15-84) increase during the fourth.

Further, the researchers found the symptom patterns during the repeated allergic reactions generally were the same within individuals (average pairwise match of symptoms, 82.4%), with commonality in symptom patterns across participants as well (78.3%).

Also, these increases in symptom severity were observed even when the researchers controlled for dose, indicating that patients may develop increased reactivity with each subsequent exposure.

Although further research into the combinations of symptoms that appear during reactions are necessary to determine whether there are tendencies for certain symptoms to co-appear, the researchers wrote, these findings will help clinicians better inform patients about the likely nature of further reactions.