Factors Associated with Incidental Neuroimaging Abnormalities in New Primary Headache Patients

BACKGROUND AND PURPOSE: Deciding whether or not to perform neuroimaging in primary headache is a dilemma for headache physicians. The aim of this study was to identify clinical predictors of incidental neuroimaging abnormalities in new patients with primary headache disorders. METHODS: This cross-sectional study was based on a prospective multicenter headache registry, and it classified 1,627 consecutive first-visit headache patients according to the third edition (beta version) of the International Classification of Headache Disorders (ICHD-3beta). Primary headache patients who underwent neuroimaging were finally enrolled in the analysis. Serious intracranial pathology was defined as serious neuroimaging abnormalities with a high degree of medical urgency. Univariable and multivariable logistic regression analyses were conducted to identify factors associated with incidental neuroimaging abnormalities. RESULTS: Neuroimaging abnormalities were present in 170 (18.3%) of 927 eligible patients. In multivariable analysis, age >/=40 years [multivariable-adjusted odds ratio (aOR)=3.37, 95% CI=2.07-6.83], male sex (aOR=1.61, 95% CI=1.12-2.32), and age >/=50 years at headache onset (aOR=1.86, 95% CI=1.24-2.78) were associated with neuroimaging abnormalities. In univariable analyses, age >/=40 years was the only independent variable associated with serious neuroimaging abnormalities (OR=3.37, 95% CI=1.17-9.66), which were found in 34 patients (3.6%). These associations did not change after further adjustment for neuroimaging modality. CONCLUSIONS: Incidental neuroimaging abnormalities were common and varied in a primary headache diagnosis. A small proportion of the patients incidentally had serious neuroimaging abnormalities, and they were predicted by age >/=40 years. These findings can be used to guide the performing of neuroimaging in primary headache disorders.