Allergy History and Psychiatric Diagnoses as Predictors of Postoperative Outcomes in Headache Surgery.

Abstract

Polyallergy is a condition characterized by multiple non-immune-mediated reactions. It has been associated with somatic symptom disorder (SSD), a psychiatric diagnosis characterized by excessive anxiety and preoccupation with physical symptoms, even without objective physical findings. SSD has been linked to a higher incidence of migraines and poorer surgical outcomes. Given these associations, this study examined whether polyallergy could serve as a preoperative marker for predicting outcomes following headache surgery involving peripheral nerve decompression. A retrospective cohort study was conducted of patients who underwent headache surgery between 2012 and 2017 with a single plastic surgeon. Patient-reported outcomes (HIT-6, MSQOL, MIDAS), psychiatric diagnoses, and allergy history were collected. Polyallergy was defined as ≥2 allergies without immune-mediated confirmation or anaphylaxis. Subgroup analyses were performed based on polyallergy and psychiatric history. Patients with polyallergy experienced significantly less improvement in HIT-6 (11.9% vs. 56.3%, p=0.002) and MIDAS (29.8% vs. 93.7%, p=0.010), with MSQOL approaching significance (44.0% vs. 138.0%, p=0.056). Polyallergy was associated with a roughly 50%-70% lower likelihood of achieving clinically significant improvement. Patients with an anxiety disorder had less improvement, but the differences were not statistically significant. There were no differences in improvement between those with and without a mood disorder. Polyallergy is associated with poorer outcomes following headache surgery and may serve as a chart-accessible marker to identify individuals at risk for suboptimal improvement. These findings offer a novel application of polyallergy as a behavioral proxy for SSD in migraine surgical care and may aid patient selection and preoperative counseling.