WEDNESDAY, Sept. 13, 2017 (HealthDay News) -- Young people who've been infected with the H1N1 swine flu virus may be at increased risk for type 1 diabetes, a new study suggests.
Researchers examined data from all the 2.28 million people aged 30 and younger in Norway between June 2009 (when pandemic H1N1 flu struck the country) and June 2014.
People who reported flu symptoms during the pandemic were 18 percent more likely to later be diagnosed with type 1 diabetes than those who did not get the flu, the investigators found.
This association was even stronger in children aged 15 or younger. Among that age group, those who were infected with H1N1 flu virus had a 25 percent increased risk of developing type 1 diabetes, according to the study.
However, the association seen in the study doesn't prove a cause-and-effect relationship.
The study findings were scheduled to be presented Wednesday at the annual meeting of the European Association for the Study of Diabetes (EASD) in Lisbon, Portugal.
People inherit a genetic susceptibility to type 1 diabetes, but an environmental trigger is also needed for it to develop, and viral infections may provide that trigger, the researchers explained in an EASD news release.
Previous research has linked H1N1 with the development of autoimmune disorders, the study authors noted.
"This study may support the hypothesis that respiratory infections can contribute to the development of type 1 diabetes, due to stress and inflammation in predisposed individuals," Paz Lopez-Doriga Ruiz and colleagues from the Norwegian Institute of Public Health and Oslo University Hospital, concluded in the news release.
Findings presented at meetings are generally viewed as preliminary until they've been published in a peer-reviewed journal.
The American Diabetes Association has more on type 1 diabetes.