Psychiatric morbidity and cognitive representations of illness in chronic daily headache

We studied patients with chronic daily headache (CDH) attending a headache clinic. Our hypothesis was that patients with anxiety or depression would have poorer functional status and differing cognitive representations of illness than would those without psychiatric morbidity.

The sample consisted of 144 consecutive new patients. Patients underwent a semistructured interview and completed a prospective headache diary, the Hospital Anxiety and Depression Scale (HADS) and other health-related questionnaires.

Sixty patients (42%) were probable cases of anxiety or depression on the basis of their HADS score. These HADS-positive cases had longer, more severe headaches, were more worried about them, were more functionally impaired and believed that their illness would last longer. Principal components analysis revealed that the HADS-positive cases believed that psychological factors play a role in their headaches.

Psychological morbidity is high amongst CDH patients who attend specialist clinics. In addition to identifying those with high levels of psychological distress, the HADS can be used to predict those likely to have worse headaches and poorer functional ability.