Migraine headaches cause Canadians to lose at least 7 million working days a year, according to Statistics Canada.
That number, and the number of people who suffer migraines, may be understated because many sufferers do not seek clinical treatment, the agency said in its 1998-99 National Population Health Survey.
One in every 12 Canadians aged 12 or older -- nearly 2 million people -- were diagnosed as having migraine headaches, the survey indicated.
Migraine can compromise productivity and lifestyle. It can result in days away from work, hinder job performance and generally restrict activities.
"Migraine sufferers reported an average of 1.8 disability days for the two-week period before the survey was taken in 1998-99, while non-sufferers reported only 0.8 days," said the report.
The survey found migraines are three times more common in women -- about 12 percent of females aged 12 or more suffered the condition, compared with 4 percent of males the same age.
According to the survey, about 56 percent of migraine sufferers reported getting treatment in 1998-99, up from 48 percent in 1996-97.
Although a large percentage did not seek medical help, those who did tended to be "relatively heavy users of health care services," the agency said.
Migraine sufferers also tended to have other health problems, the study noted.
Nearly 30 percent of females and 20 percent of males with migraines reported other chronic conditions such as allergies, arthritis and rheumatism, back problems, sinusitis and ulcers.
by Virginia Sutcliffe