Comorbidity refers to the greater than coincidental association of two conditions in the same individual. The medical conditions that link to migraine are:
Respiratory-allergic rhinitis and asthma 17%
Cardiovascular-hypertension, angina/myocardial infarction, Raynaud’s syndrome, stroke, congenital heart defect-mitral valve prolapse, patent foramen ovale (PFO) and atrial septal defect (ASA)
Gastrointestinal-ulcer disease, ulcerative colitis, and irritable bowel syndrome 60%
Neurologic-epilepsy, tension-type headache, and essential tremor
Psychiatric-mood disorders, depression 50%, bipolar disorder, generalized anxiety disorder 34%, panic disorder, agoraphobia, chronic fatigue 20%, obsessive-compulsive disorder.