Furthermore, based on the age and sex of the study cohort, which was predominantly male, investigators found there was a 2-fold increased prevalence of migraine among these veterans compared with the general population.
“These findings indicate soldiers with migraine are more likely to have symptoms of psychiatric conditions after a combat tour, with depression and PTSD being the most prevalent,” said the study’s principal investigator, Maj. Jay C. Erickson, MD, PhD, from the Madigan Army Medical Center, in Tacoma, Washington.
“This is the first study to examine the co-occurrence of migraines and psychiatric conditions in a military population. In addition, we think it may be the first study in any population to establish a possible link between migraine and PTSD,” he added.
The study was presented at American Academy of Neurology 59th Annual Meeting, in Boston, Massachusetts.
Migraine Prevalence 2-Fold Higher In Veterans
The cross-sectional study involved 3621 US soldiers who were asked to complete a voluntary migraine headache questionnaire based on International Headache Society criteria within 90 days of returning from a 1-year combat tour in Iraq. This screening instrument assessed headache frequency, severity, and duration in the last 3 months of deployment.
In addition, soldiers were asked to complete the Patient Health Questionnaire to screen for depression and anxiety and the Primary Care PTSD Screen to determine symptoms of PTSD.
In all, 2167 soldiers (60%) completed the questionnaire. Of the total study group, 19% screened positive for migraine, 32% screened positive for depression, 22% screened positive for PTSD, and 13% had anxiety. The average age of participants was 27 years and 96% were male.
Dr. Erickson pointed out that if this study had been conducted in an age- and sex-matched general population, the expected prevalence of migraine would be about 10%.
“What we have seen [in this study] is migraine prevalence that is 2-fold higher than you would expect in a general population based on age and gender,” he said.
When investigators compared the screening prevalence of each psychiatric condition in soldiers with migraine with nonmigraineurs they found individuals who screened positive for migraine were much more likely to have 1 or more psychiatric disorders. Overall, said Dr. Erickson, symptoms of 1 or more psychiatric conditions were present in 58% of soldiers with migraine vs 34% without migraine.
Prevalence of Psychiatric Disorders Among US Soldiers With Migraine vs Soldiers Without Migraine
|
Psychiatric Disorder
|
US Soldiers With Migraine (%)
|
US Soldiers Without Migraine (%)
|
|
Depression
|
50
|
27
|
|
PTSD
|
39
|
18
|
|
Anxiety
|
17
|
7
|
The study also found individuals with migraine and depression had more frequent headaches than those with migraine and no depression — an average of 3.5 headache days per month vs 2.5 days per month, respectively. The findings were similar for those with migraine and PTSD.
In contrast, said Dr. Erickson, anxiety did not affect headache frequency in subjects with migraine. In addition, neither pain severity or duration of migraines was significantly different among soldiers with and without symptoms of any of the study’s psychiatric conditions.
“These findings indicate that soldiers with migraine headaches are more likely to have certain psychiatric conditions following combat deployment. This knowledge should assist in the early diagnosis and treatment of soldiers with these health problems,” said Dr. Erickson.
He added that healthcare providers evaluating soldiers with migraine headaches should also perform mental health screening to ensure comorbid psychiatric disorders are identified and properly treated in this high-risk population.
Potential Shared Mechanism
At this point, the link between migraine and psychiatric disorders is not well understood. However, said Dr. Erickson, 1 possible shared biological mechanism may be altered signaling in the serotonin system as well as the norepinephrine system, both of which have been associated with migraine and the psychiatric disorders included in the study.
“Additional studies are needed to better understand the relationship between migraines and psychiatric conditions in military members. A better understanding of the shared mechanism could lead to improved prevention and treatment for migraines and psychiatric conditions in deployed military personnel,” he said.
American Academy of Neurology 59th Annual Meeting: Abstract P06.035. April 28 – May 5, 2007.
