A new study provided additional evidence that nerve stimulation can reduce pain and the number of headaches for patients who suffer from chronic migraines, St. Jude Medical Inc. said Wednesday.

The study results were published online in Cephalalgia, the journal of the International Headache Society.

The study followed 157 patients who, on average, suffered from migraines 21 days per month. Some were implanted with St. Jude's Genesis neurostimulator. At 12 weeks, patients receiving stimulation reported an average of six fewer headache days per month.

"For the millions who suffer from chronic migraine, these study results are important, as they confirm that peripheral nerve stimulation of the occipital nerve may help improve their quality of life," said Stephen Silberstein, director of the Jefferson Headache Center, in a statement. He was the principal investigator in the study.

Nerve stimulation therapy involves delivery of mild electrical pulses to the occipital nerves just beneath the skin at the back of the head. Patients receiving the treatment were more likely than those in the study's control group to experience 30 percent or greater pain reduction.

St. Jude, based in Little Canada, said it received European regulatory approval for the Genesis device about a year ago.

Adam Belz • 612-673-4405 Twitter: @adambelz