The family of a British man who died after engaging in marathon Xbox sessions is launching a campaign to raise awareness about the risks of prolonged game and computer use.

Chris Staniforth, 20, of Sheffield died in May after suffering from deep vein thrombosis (DVT), according to autopsy results. A blood clot formed in his left calf and traveled to his lungs, causing a pulmonary embolism.

BBC News

The Halo fan logged sessions of up to 12 hours on Xbox. He was hoping to start a career in video games, but collapsed outside an employment center after complaining to a friend of chest pain.

"Chris loved to play and would stay up all night," his father David was quoted as saying by BBC News. "Millions of people worldwide are playing these games for hours, and there is a risk.

"After my research I saw there was no difference to Chris sitting at a desk on his Xbox and someone on a long-haul flight," he said, adding that he is setting up a Web site about the DVT awareness campaign.

Often associated with sitting in cramped seating on long-haul flights, DVT can occur when the body is immobile for long periods, though it has other causes as well.

A 2008 Office of the Surgeon General report (PDF) estimated there are more than 350,000 cases of DVT and pulmonary embolism in the U.S. annually, and stated that they often go undetected.

Microsoft's Healthy Gaming Guide warns that "use of game controllers, keyboards, mice, or other electronic input devices may be linked to serious injuries or disorders." It also encourages gamers to take breaks and to lead a healthy lifestyle.