Outcome of patients with chronic migraine with medication overuse and depression after duloxetine: influence of coexisting obsessive compulsive disorder.

Patients with chronic migraine (CM) and medication overuse (MO) have high frequency of psychiatric comorbidity. Aims of this open label, prospective, independent study were: to evaluate the efficacy of duloxetine in a sample of patients with MO due to CM and with concomitant depression; to investigate, if the presence of OCD influences the outcome in this subgroup of patients. A total of 50 consecutive patients (40 F,10 M, aged 20-65 years, mean 39.4 years) from those attending our Headache Center to undergo an inpatient withdrawal programme followed by anti-migraine prophylaxis was enrolled. After a 1-month baseline period, all patients were prescribed duloxetine 30 mg in the morning for the first week, and 60 mg for the following 12 weeks. They filled a daily headache diary during the whole study period. They also completed Hamilton depression rating scale (HDRS) and migraine disability assessment scale (MIDAS) at baseline and at the 12-week follow-up. The primary outcome measure was the percentage of responders, i.e. of patients with a reduction ≥50 % in headache frequency as well as in symptomatic drug consumption. Comparison between patients with and without OCD was performed. Our results showed a rather high responder rate in the total sample (64 %), while none of the patients with OCD fell among responders. MIDAS and HDRS scores had a more evident decrease in patients without OSD. These findings suggest that duloxetine may be effective in patients with MO due to CM and with comorbid depression. They also confirm the importance of a systematic assessment of the psychopathological profile in these patients, and indicate that clinicians should be aware of the relevant prognostic role of OCD in favoring a poor outcome and persistent disability in headache patients with MO.