Characteristics of Elderly-Onset (≥65 years) Headache Diagnosed Using the International Classification of Headache Disorders, Third Edition Beta Version

New-onset headache in elderly patients is generally suggestive of a high probability of secondary headache, and the subtypes of primary headache diagnoses are still unclear in the elderly. This study investigated the characteristics of headache with an older age at onset (≥65 years) and compared the characteristics between younger and older age groups. We prospectively collected demographic and clinical data of 1,627 patients who first visited 11 tertiary hospitals in Korea due to headache between August 2014 and February 2015. Headache subtype was categorized according to the International Classification of Headache Disorders, Third Edition Beta Version. In total, 152 patients (9.3%, 106 women and 46 men) experienced headache that began from 65 years of age [elderly-onset group (EOG)], while the remaining 1,475 patients who first experienced headache before the age of 65 years were classified as the younger-age-at-onset group (YOG). Among the primary headache types, tension-type headache (55.6% vs. 28.8%) and other primary headache disorders (OPH, 31.0% vs. 17.3%) were more common in the EOG than in the YOG, while migraine was less frequent (13.5% vs. 52.2%) (p=0.001) in the EOG. Among OPH, primary stabbing headache (87.2%) was more frequent in the EOG than in the YOG (p=0.032). The pain was significantly less severe (p=0.026) and the frequency of medication overuse headache was higher in EOG than in YOG (23.5% vs. 7.6%, p=0.040). Tension-type headache and OPH headaches, primarily stabbing headache, were more common in EOG patients than in YOG patients. The pain intensity, distribution of headache diagnoses, and frequency of medication overuse differed according to the age at headache onset.