The CHORD (Canadian Headache Outpatient Registry and Database) Project studied demographic and clinical data for new patients referred to headache clinics.  The Beck Depression Inventory (BDI) was used to identify the presence of depression.  The researchers found that there were a number of factors that were associated with headache patients and depression, such as being unemployed, under age 50, being on disability pension or welfare, being widowed, separated or divorced or a diagnosis of transformed migraine or headache associated with head trauma or cervical spine disorder.

Comorbidty of migraine and depression is bi-directional.  Patients with migraine are at a higher risk for developing depression and patients with depression are a higher risk for developing migraine.  Do migraine and depression share the same etiologies?  It has been demonstrated that comorbidity of depression in headache patients leads to poorer headache management outcomes. Another serious neurological concern, the risk of stroke, almost doubles with each decade of age during adulthood.  The highest risk is among people 85 years or older.  The risk of a first stroke for all ages together is 183 per 100,000 people.  The risk of stroke is twice as high for Hispanic and African Americans as for whites.

The CHORD study evaluated data on 712 patients, of which the mean ages was 40.5 years and 78.2% were female.  Evaluation tools included the MIDAS questionnaire and the HIT-6.  The two strongest factors associated with depression among headache patients were being on disability or welfare and those with severe headaches, as demonstrated on the HIT-6.  Patients under 30 were 2 times more likely to suffer from depression than those over 50 years of age.  MIDAS results demonstrated that the degree of disability is the most powerful predictor of depression in headache patients. 

These results are consistent with earlier studies.  Of patients with headache on more than four days/week, 51% had a BDI score greater than 9.  Tension headaches were not found to be associated with depression in this study.  Individuals with migraine have an increased chance of developing depression later.  Severe headaches not related to migraine have only a unilateral relationhship to depression.

Determining headache patients who are at a higher risk of comorbities, such as depression, is helpful in developing an effective treatment plan.  Those patients at highest risk should be carefully assessed for depression.   The CHORD study results reinforces the fact that social history is an important component of care and needs to be integrated into any assessment.