Background: MOH can be diagnosed in subjects with
headache occurring 15 days/month in association with a regular
medication overuse, but its existence is not universally accepted. ICHD-3 redefined criteria for MOH, removing the criterion associating drug
suspension with
headache course. The aim of our study was to compare the rate of patients diagnosed with
medication overuse headache (MOH) according to ICHD-2 and ICHD-3 criteria, to verify the degree of concordance. The secondary aim was to verify if drug withdrawal was really associated with
pain relief. Methods: In this cross-sectional study, we retrospectively analyzed a sample of 400 patients followed for primary
chronic headache at the
Headache Center of Bambino Gesù Children's Hospital. We then selected those presenting with a history of
medication overuse, and we applied both ICHD-2 and ICHD-3 criteria to verify in which patients the criteria would identify a clinical diagnosis of MOH. Results: We identified 42 subjects (10.5%) with MOH; 23 of them (55%) presented a relief of
headache withdrawing drug overuse. Regarding the applicability of the ICHD-2 criteria, 43% of patients (18/42) fulfilled all criteria, while all ICHD-3 diagnostic criteria were satisfied in 76% of patients (32/42). Eighteen patients (43%) satisfied both ICHD-2 and ICHD-3 criteria, while 10 patients (24%) did not satisfy either diagnostic criterion. Conclusions: Our study suggests that in children and adolescents, withdrawing
medication overuse is not always associated with a clinical benefit. Therefore, though allowing a MOH diagnosis in a higher rate of patients as compared to ICHD-2, the application of ICHD-3 criteria does not guarantee a true a causal relationship between
medication overuse and
headache worsening.