The study included over 8,400 individuals who were followed for 20 years. Those participants with pre-existing headache disorders had a 21 percent higher risk of hypothyroidism, and people with possible migraine disorders had a 41 percent higher risk of underactive thyroid.
The findings suggest that migraine and headache sufferers are at a higher risk of hypothyroidism, but the study did not establish causality, only an association.
Coauthor of the study Dr. Vincent Martin said, “It is possible that the development of hypothyroidism in a headache patient might further increase the frequency of headache, as past studies have found that treatment of hypothyroidism reduces the frequency of headache. Regardless, physicians should be more vigilant in testing for hypothyroidism in persons with headache disorders.”
The findings were published in Headache: The Journal of Head and Face Pain.