ry eye disease (DED) is a disorder affecting a significant proportion of the general population, with estimated prevalence rates ranging from 7.4% to 33.7%. 1-3 This multifactorial disorder of the tear film and ocular surface results in symptoms of discomfort, visual disturbance, increased tear film osmolarity, and tear film instability, all of which can lead to inflammation of the ocular surface and a diminished quality of life. 4 Similar to DED, the prevalence of migraine headaches among the general population is also quite high, with estimates as high as 14.2% in the United States alone. 5 Among previous investigations regarding the link between DED and migraine headaches, some have demonstrated an association between the 2 disorders. 6,7 Objective and clinical variables used to assess the presence and severity of DED, such as tear osmolarity, tear film breakup time, and Schirmer testing results, can also differ significantly between patients with migraine headaches and control individuals without the disorder. 8-10 Although prior studies in this area shed some light on the possible link between migraine headaches and DED, they possess inherent limitations. Such studies, including some of those cited above, 2,7 are population-based cross-sectional studies that rely on patientreported, subjective assessments of disease symptoms, such as questionnaires or surveys. 7 Those studies that rely on more objective variables when assessing the presence or absence of IMPORTANCE Reports in the literature have conflicting findings about an association between dry eye disease (DED) and migraine headaches. OBJECTIVE To determine the strength of the association between DED and migraine headaches.