Obesity may not bring on migraine

NEW YORK (Reuters Health) - Obese middle-age and older women appear no more likely to report migraine than their non-obese counterparts, a new study suggests.

Some previous studies have suggested that there is a relationship between obesity and migraine, while others have found no connection.

To further investigate, Dr. Peter Mattsson, of the department of Neuroscience and Neurology at University Hospital in Uppsala, Sweden enrolled 684 women, age 40 to 74 years, who were attending a mammography screening clinic between November 1997 and October 1998.

Mattsson looked for an association between migraine and body mass index, a ratio of height to weight commonly used to determine if an individual is over- or underweight. His findings are reported in the medical journal Cephalalgia.

Overall, 19 percent of the women reported active migraine -- one or more migraine attacks during the previous year. Another 14 percent had inactive migraine -- previous migraine but not within the past year. Just over 19 percent of the study population was obese.

Mattsson found no association between active migraine or inactive migraine and obesity in this population of women. Thirty-two percent of the obese women had active migraine and 38 percent of the non-obese women had active migraine, a difference that was not statistically significant. Similar findings were obtained for inactive migraine.

He also found significant relationship between migraine characteristics -- frequency, intensity, and duration - and obesity in the study participants.

Mattsson notes that one recent population-based study, using interviews conducted by non-medical personnel and self-reports of physical characteristics, found an increased risk of migraine among obese and morbidly obese individuals compared with those of normal weight.

By contrast, Mattsson based his conclusions on data from interviews conducted by neurologists and actual body weight and height measurements. He found "no evidence in this study that obesity affects the prevalence of migraine among middle-aged and older women."

"If there are true associations between obesity and features of migraine such as frequency, these are likely to be small, and cannot be reliably studied in small or moderately sized community samples," Mattsson concludes.

SOURCE: Cephalalgia, August 2007.