LONDON—Results of a large study suggest that watching television for prolonged periods may increase a person’s risk of fatal pulmonary embolism (PE).
The study, which included more than 86,000 subjects, showed that watching an average of 5 or more hours of TV per day was associated with more than twice the risk of fatal PE as watching less than 2.5 hours daily.
And the risk was higher among younger subjects than older ones.
Toru Shirakawa, of Osaka University in Japan, presented this research at the ESC Congress 2015 (abstract P2686*).
“We showed that prolonged television viewing may be a risky behavior for death from pulmonary embolism,” Shirakawa said. “Leg immobility during television viewing may, in part, explain the finding. Public awareness of the risk of pulmonary embolism from lengthy leg immobility is essential.”
For this research, Shirakawa and his colleagues evaluated 86,024 individuals—36,007 men and 50,017 women ages 40 to 79—who were participating in the Japanese Collaborative Cohort Study.
The subjects completed a self-administered questionnaire that included information about average time spent watching TV each day. They were followed for a median of 18.4 years until 2009. Mortality from PE was determined from death certificates.
Subjects were divided into 3 groups according to the amount of TV they watched per day: less than 2.5 hours, 2.5 to 4.9 hours, and 5 or more hours.
The researchers calculated the risk of death from PE according to the amount of TV watched after adjusting for subjects’ age at baseline, gender, history of hypertension, history of diabetes, smoking status, drinking status, body mass index, walking and sports habits, and menopausal status.
During the follow-up period, there were 59 deaths from PE. And the multiavariate analysis revealed a link between extended TV viewing and fatal PE.
Compared to subjects who tended to watch less than 2.5 hours of TV per day, those who watched an average of 2.5 to 4.9 hours had an increased risk of fatal PE (hazard ratio [HR]=1.59). And the risk was greater among subjects whose average TV viewing time was more than 5 hours per day (HR=2.36).
Among subjects ages 40 to 59, the association between prolonged TV watching and fatal PE was more prominent.
Watching 2.5 to 4.9 hours of TV a day more than tripled the risk of fatal PE when compared to watching less than 2.5 hours (HR=3.24). And watching TV for more than 5 hours a day was associated with a more than 6-fold greater risk of fatal PE than watching less than 2.5 hours (HR=6.49).
Because prolonged leg immobility may explain these findings, Shirakawa and his colleagues recommend taking simple steps to prevent PE while watching TV for extended periods.
“[T]ake a break, stand up, and walk around during the television viewing,” he said. “Drinking water for preventing dehydration is also important.”
Shirakawa also noted that other media-based activities involving prolonged sitting may pose a risk of fatal PE.
“In this era of information technology, use of other visual-based media devices, such as personal computers or smartphones, is popular,” he said.
“Prolonged computer gaming has been associated with death from pulmonary embolism, but, to our knowledge, a relationship with prolonged smartphone use has not yet been reported. More research is needed to assess the risks of prolonged use of new technologies on pulmonary embolism morbidity and mortality.”
*Information in the abstract differs from that presented at the meeting.