P055. Prevalence of migraine in subclinical hypothyroidism: a case-control study

Background The existence of an association between migraine and thyroid diseases is still a matter of debate. Epidemiological studies have shown a potential association between plasma TSH concentrations and migraine but results are contradictory. Subclinical hypothyroidism (SCH) is a common clinical entity defined biochemically as a normal serum free thyroxine (fT4) concentration in the presence of an elevated serum thyroid-stimulating hormone (TSH) concentration. In population-based studies, the prevalence of SCH ranges from 4 to 15 percent, the diagnosis being more common in women and in old age. Prospective data have shown that SCH is a risk factor for coronary heart disease, heart failure, and cardiovascular mortality, probably related to a mechanism of endothelial dysfunction and low grade chronic inflammation. A recent study suggested an increased prevalence of subclinical hypothyroidism in childhood migraine. The purpose of this study was to evaluate the prevalence and clinical characteristics of migraine in patients with subclinical hypothyroidism.