Association of psychiatric co-morbidity and efficacy of treatment in chronic daily headache in Indian population

OBJECTIVE: To study the prevalence of psychiatric co-morbidity in patients of chronic daily headache (CDH) and compare the efficacy of treatment between various type of headache associated with psychiatric co-morbidity. MATERIALS AND METHODS: Prospective case control cohort study, 92 consecutive patients of CDH meeting eligibility criteria. The diagnosis of various subtypes of CDH was made according to the IHS criteria. Age, sex, educational, marital and socioeconomic status, matched controls were also selected. Patients were evaluated with the Mini International Neuropsychiatric Interview (MINI) scale at the time of enrolment and at 3 months. RESULTS: CDH accounted for 28% of all headache patients. The mean age of presentation was 30.2 ± 10.3 years, male: Female ratio of 28:64 and mean duration of 4.56 ± 0.56 years. Chronic migraine (CM) accounted for 59 patients, chronic tension type headache (CTTH) 22 patients, new daily persistent headache (NDPH) 3 patients and miscellaneous 8 patients. Psychiatric co-morbidity was present in 53.3% patients with CDH, and was more common in CM (62.7%) as compared to CTTH (36.4%). Single psychiatric co-morbidity was seen in 26 patients, while 23 patients had multiple co-morbidity. Major depressive episode, anxiety disorder, agoraphobia and dysthymia were significant psychiatric co-morbidities. Patients with CM were treated with topiramate or divalproex sodium ER and CTTH were treated with amitriptyline. 55 patients came for follow up at 3 months, improvement in headache was seen in 29 patients. CONCLUSION: Psychiatric co-morbidity was present in more than 50% patients with CDH and its presence along with a duration of ≥2 years was associated with a poor response to treatment.