Comorbidities of primary headache disorders: a literature review with meta-analysis.

Some of the most relevant comorbidities of primary headache disorders - back pain, anxiety and depression, diabetes, ischemic heart disease and stroke - are among the most burdensome conditions, together with headache themselves, according to the GBD study. A joint treatment of headaches and of these comorbidities may positively impact on headache sufferers' health status and contribute to reduce the impact of a group of highly burdensome diseases.