Psychiatric comorbidity in medication overuse headache patients with pre-existing headache type of episodic tension-type headache.

BACKGROUND: Medication overuse headache (MOH) mostly evolves from migraine and episodic tension-type headache (ETTH). Chronic tension-type headache (CTTH) is another headache type that evolves over time from ETTH. It is well known that psychiatric comorbidity is high in MOH patients.

AIM: To investigate the frequency of psychiatric comorbidity, and the intensity of depression and anxiety in MOH patients evolving from ETTH and to compare results with CTTH patients and MOH patients evolving from migraine.

METHODS: Twenty-eight CTTH (Group C) and 89 MOH patients were included into the study. MOH patients were divided into two groups according to their pre-existing headache types: MOH patients with pre-existing ETTH (Group E, n = 31), and with pre-existing migraine (Group M, n = 58). All patients were interviewed with a psychiatrist and SCID-CV and SCID-II were applied. Beck Anxiety Inventory and Beck Depression Inventory scales were also performed.

RESULTS: Eleven patients (39.3%) in Group C, 21 patients (67.7%) in Group E, and 31 patients (53.7%) in Group M were diagnosed to have comorbid psychiatric disorders. The psychiatric comorbidity was found significantly higher in Group E than Group C. In Group E, mood disorders were found significantly higher, but the difference between the two groups with regard to anxiety disorders was insignificant. Mean depression scores were significantly higher in Group E than Group C. The mostly diagnosed type was obsessive-compulsive personality disorder in all the three groups, and was statistically significant in Group M than Group C.

CONCLUSION: Psychiatric comorbidity in MOH patients with pre-existing ETTH is common as in those with pre-existing migraine headache and MOH with regard to developing psychiatric disorders should be interpreted as a risk factor in chronic daily headache patients.