The pain is generally made worse by physical activity. Migraines are believed to be due to a mixture of environmental and genetic factors. It is, however, believed to be a neurovascular disorder. A total of 160 questionnaires were analysed. Headaches were reported by 80% of subjects, with 49% of respondents reporting headaches during competitive match play and 60% during training.
In a multivariate model adjusted for gender, age, occupational training, living alone, metabolic equivalent of task, body mass index and alcohol consumption, self-reported migraine predicted hypertension (odds ratio 1.39; 95% confidence interval 1.19-1.64) for the self-reported and (odds ratio 1.42; 95% confidence interval 1.13-1.77) for the register data of the Social Insurance Institution.