Phenotypic characterization of acute headache attributed to SARS-CoV-2: An ICHD-3 validation study on 106 hospitalized patients

Introduction: Headache is a common symptom of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. In this study, we aimed to characterize the phenotype of headache attributed to SARS-CoV-2 infection and to test the International Classification of Headache Disorders (ICHD-3) phenotypic criteria for migraine and tension-type headache.
Methods: The study design was a cross-sectional study nested in a cohort. We screened all consecutive patients that were hospitalized and had a positive SARS-CoV-2 test. We included patients that described headache if the headache was not better explained by another ICHD-3 diagnosis. Patients were interviewed by two neurologists.
Results: We screened 580 patients and included 130 (mean age 56 years, 64% female). Headache was the first symptom of the infection in 26% of patients and appeared within 24 hours in 62% of patients. The headache was bilateral in 85%, frontal in 83%, and with pressing quality in 75% of patients. Mean intensity was 7.1, being severe in 64%. Hypersensitivity to stimuli occurred in 57% of patients. ICHD-3 criteria for headache attributed to systemic viral infection were fulfilled by 94% of patients; phenotypic criteria for migraine were fulfilled by 25% of patients, and tension-type headache criteria by 54% of patients.
Conclusion: Headache attributed to SARS-CoV-2 infection in hospitalized patients has severe intensity, frontal predominance and oppressive quality. It occurs early in the course of the disease. Most patients fulfilled ICHD-3 criteria for headache attributed to systemic viral infection; however, the phenotype might resemble migraine in a quarter of cases and tension-type headache in half of the patients.