MIAMI BEACH – Comorbid psychiatric conditions are common in patients with headache disorders, and can adversely affect the prognosis in patients with such disorders, Alvin E. Lake III, Ph.D., said at a symposium sponsored by the American Headache Society.
However, combined behavioral and drug therapy as well as patient education have been shown to improve outcomes, said Dr. Lake, director of the behavioral medicine division at the Michigan Headache and Neurological Institute, Ann Arbor.
Studies suggest that close to 50% of patients with chronic daily headache have an anxiety and/or mood disorder. In those with medication overuse headaches, the prevalence of mood and anxiety disorders appears to be even higher at 68%, according to one study.
Headache patients with psychiatric disorders also appear to have poorer long-term outcomes than do those with no psychiatric disorder. In one study, 57% of patients with multiple psychiatric disorders had worsening of their headaches over an 8-year period, compared with 7% of those with no psychiatric disorder. In addition, 29% of those with multiple psychiatric disorders experienced improvement, compared with 53% of those with no psychiatric disorder.
It appears that in most cases, the psychiatric disorders preceded the headache disorders. In a study of 41 patients with medication overuse headaches and comorbid psychiatric disorders, the psychiatric disorder preceded the headaches in 76% of those with a major depressive episode, 79% of those with panic disorder, 80% of those with generalized anxiety disorder, 89% of those with substance abuse disorder, and 100% of those with social phobia, Dr. Lake noted.
In addition to mood disorders, which have a genetic component, psychological factors, such as anticipatory fear of pain, and psychosocial factors, such as family and work pressures and a need to function, can drive excessive use of preemptive treatment, which in turn can lead to headache chronicity, he explained.
In one study of headache patients, the use of analgesics at initial assessment was associated with a relative risk of 19.6 for chronic daily headaches at 11-year follow-up, compared with a relative risk of 3.1 in those without analgesic overuse. Daily or weekly analgesic use also elevated the risk for chronic pain; in those who used analgesics more than 15 days per month, the relative risk of chronic migraine was 13.3 and the relative risk of nonmigraine headache was 6.2, compared with those without analgesic overuse.
Differential attention to the headache pain has been shown to modulate the subjective experience of pain, Dr. Lake said.
For example, attention to pain location increases responses in the somatosensory cortex, while attention to the unpleasantness of the pain increases responses in the limbic system.
Distraction, such as activities that divert attention away from the pain, can lower pain intensity and increase brain stem periaqueductal gray activation, which has been shown to predict changes in perceived pain intensity.
Thus, behavioral therapy is useful in this patient population. Several studies demonstrate improved outcomes with combined treatment.
For example, in one study of patients with chronic tension headaches, 64% of patients who received tricyclic antidepressants as well as stress management training had improvement at 8 months, compared with 29% of placebo patients, 38% of those on tricyclic antidepressants alone, and 35% who received stress management training alone.
In another study of patients with medication overuse headaches, headache days per month were reduced at 3 years' follow-up from 30 to 11 days in patients who received inpatient pharmacologic therapy and biofeedback-assisted relaxation training, compared with a reduction from 30 to 18 days in those who received only inpatient pharmacologic therapy.
Analgesic doses per month were reduced from 59 to 4 doses in the combination treatment group, compared with a reduction from 59 to 20 doses in those with preventive medication treatment alone. The relapse rate to medication overuse headaches was 13% in the combination treatment group, compared with 42% in the medication-only group.
Patient education has also been shown to be of benefit, Dr. Lake said.
A study published in May 2006 showed that patients who attended three 90-minute educational sessions taught by intensively trained lay migraineurs was useful for improving outcomes and reducing analgesic overuse (Headache 2006;46:726–31).
Of 100 consecutive migraine patients who received routine medical management and were randomly assigned to attend or not attend the classes–which offered information on migraine pathogenesis, management, and risks of rebound–those who attended had a significantly greater reduction in mean migraine disability assessment scores (reduction of 24 vs. 14 points) at 6 months.
They also had fewer headache days per month, less headache-related dysfunction, less abortive medication use, less analgesic overuse, and fewer headache-related phone calls and unscheduled visits to doctors, Dr. Lake said.