Obesity and Headache
Created 06-12-2008
Obesity has been called the most common disease in America, although technically I believe dental decay holds that distinction. From the decade of the 1960s to the decade of the 1970s, medical epidemiologists, the folks who study statistics about diseases, found that the number of people with headaches, and especially migraines, was increasing. But they didn't know why.
Now, it may partly be due to increased stress in our lives. And it may partly be that migraines are being diagnosed more. However, the increasing waistlines of the US may also be contributing to an increase in headache severity.
In 2002, Dr. Dawn Marcus noted that pro-inflammatory chemicals called cytokines had been discovered in migraine, and that they had been found to be elevated in obesity. She conducted a small pilot study (61 headache patients) to look for a relationship between obesity and migraine. She found that obesity was related to headache impact on a validated test of pain severity, psychological distress, and quality of life. The test scores were significantly higher in obese patients.
Medical geneticists are currently hard at work to see whether there is a genetic link between migraine, obesity, hyperlipidemia (elevated cholesterol and other blood fats), high blood pressure (hypertension), and other chronic conditions.
In 2003, a large study was completed looking at the various risk factors for the development of chronic daily headache. Some things we already knew about or suspected, like medication overuse, or not sleeping. But an association with weight was a surprise to headache specialists.
This study, conducted by Dr. Ann Scher and colleagues, involved just over 1,100 people who were followed for a year. The obese people were far more likely to develop chronic daily headache (not acute migraine) than the normal group. Chronic daily headache is defined as headaches which occur 15 days a month or more.
In a more recent study, Dr. Marcelo Bigal, interviewed over 143,000 people in order to identify nearly 1,100 with chronic daily headache. Sixty-four per cent of the study population was female. Obese individuals, those with a body mass index (BMI) of 30 or more, were about twice as likely to develop chronic daily headache, 7% vs. 3.8% for the normal group. Those who were just overweight-BMI between 25 and 29.9-had a 5% risk of developing CDH. The people at greatest risk were obese middle-aged women.
The obese group were also more likely to miss work due to their headaches. When asked if they had missed more than four days of work, 33% of the obese group answered yes, as compared to 27% of the overweight group and 26% of the underweight group.
We do not yet know whether losing weight will reduce the frequency and severity of headaches. Some headache specialists feel that this may be so, while others simply suspect that the same risk factors that contribute to obesity also contribute to headache.
Further, if you have chronic headaches, you are less likely to be active or to exercise.
The positive finding is that obese chronic daily headache sufferers were just as responsive to treatment as were other patients. In a second study, Dr. Bigal and his colleagues compared the treatment outcomes of 170 migraine patients. They found that after three months of treatment, response rates were about the same in all weight classes.
So, the good news is that whether obesity is the chicken or the egg in chronic daily headache, treatment strategies are still effective.
By Christina Peterson, MD
