A painter who developed a blood clot in his leg while spending hours on his bed playing video games has sparked concerns about a potentially wider risk among extreme gamers.
Three doctors from Middlemore Hospital investigated how the 31-year-old man quickly developed deep vein thrombosis (DVT) while using his holiday to play PlayStation games.
They say the rare case should serve as a cautionary tale to all gamers.
"We were looking after a patient who came into the hospital, and we were interested in this guy's story," said respiratory physician Dr Conroy Wong, a co-author of the study published this month in the Journal of Medical Case Reports.
The man presented with pain and swelling in his left leg after sitting on his bed for seven to eight hours each day of his holiday with outstretched legs playing PlayStation games.
He developed leg pain associated with calf swelling and erythema as early as the second day, and despite increasing pain, played on before arriving at hospital two days later.
Doctors noted he had no history of trauma to his left leg, recent surgery or previous DVT, nor was there any family history of DVT.
An examination found marked swelling in his left leg with dilated superficial veins, before an ultrasound test confirmed extensive DVT.
Doctors initiated anticoagulation and thrombolysis, treatments to break down the blood clot.
"We see a number of people who die from pulmonary embolism, which is where the clot breaks off from the leg and travels to the lung, so it's not a condition to be taken lightly," Dr Wong said.
But it was the cause of the case that came as an "eye-opener" to Dr Wong and his colleagues.
"He didn't seem to have any obvious risk factors, and as we got into the story more, it was obvious he'd been lying on his bed for hours and hours, which was a bit of a surprise to us.
"We knew a lot of people do play video games, but we found in fact there is remarkably little that has actually been published on this."
Most research on DVT involved "economy class syndrome", where it affected the legs of passengers cooped up on long-haul flights.
Dr Wong said many gamers were older today, putting them at more risk of developing the condition. In the US, the age of gamers had increased; as at last year 37 per cent of American video gamers were older than 36.
Time gaming had also increaased, and the risk of DVT was likely to be higher in "extreme gamers" who represented 4 per cent of the total US gaming population and spent more than 48 hours each week playing.
In 2004, a 24-year-old died from a blood clot after an 80-hour marathon, while in 2011, British 20-year-old Chris Staniforth died the same way after spending up to 12 hours a day on his Xbox.
Mr Staniforth's father has set up a website Take Time Out offering information and advice to gamers.
Dr Wong said the main reason for the study was "really just to highlight that if you sit down playing games for a long time, it's a potential risk for your health".
Sony and Microsoft, which make PlayStation and Xbox, couldn't be reached for comment yesterday.
* Deep vein thrombosis (DVT) is a condition in which a blood clot, or a thrombus, forms mainly in the deep veins of the legs.
* Complications arise when this clot or a portion of it breaks away from the wall of the vein to which it is attached.
* After being carried in circulation, it may reach the lung, causing chest pain, or in the worst case, death.
* ACC lists such DVT risk factors as long-haul air travel, surgical trauma, immobilisation, leg paralysis, inherited disorders and being over the age of 40.