title: Screen-based entertainment time, all-cause mortality, and cardiovascular events: population-based study with ongoing mortality and hospital events follow-up.
abstract: OBJECTIVE
  The aim of this study was to examine the independent relationships of television viewing or other screen-based entertainment ("screen time") with all-cause mortality and clinically confirmed cardiovascular disease (CVD) events. A secondary objective was to examine the extent to which metabolic (body mass index, high-density lipoprotein and total cholesterol) and inflammatory (C-reactive protein) markers mediate the relationship between screen time and CVD events.
  
  
  BACKGROUND
  Although some evidence suggests that prolonged sitting is linked to CVD risk factor development regardless of physical activity participation, studies with hard outcomes are scarce.
  
  
  METHODS
  A population sample of 4,512 (1,945 men) Scottish Health Survey 2003 respondents (≥35 years) were followed up to 2007 for all-cause mortality and CVD events (fatal and nonfatal combined). Main exposures were interviewer-assessed screen time (<2 h/day; 2 to <4 h/day; and ≥4 h/day) and moderate to vigorous intensity physical activity.
  
  
  RESULTS
  Two hundred fifteen CVD events and 325 any-cause deaths occurred during 19,364 follow-up person-years. The covariable (age, sex, ethnicity, obesity, smoking, social class, long-standing illness, marital status, diabetes, hypertension)-adjusted hazard ratio (HR) for all-cause mortality was 1.52 (95% confidence interval [CI]: 1.06 to 2.16) and for CVD events was 2.30 (95% CI: 1.33 to 3.96) for participants engaging in ≥4 h/day of screen time relative to <2 h/day. Adjusting for physical activity attenuated these associations only slightly (all-cause mortality: HR: 1.48, 95% CI: 1.04 to 2.13; CVD events: HR: 2.25, 95% CI: 1.30 to 3.89). Exclusion of participants with CVD events in the first 2 years of follow-up and previous cancer registrations did not change these results appreciably. Approximately 25% of the association between screen time and CVD events was explained collectively by C-reactive protein, body mass index, and high-density lipoprotein cholesterol.
  
  
  CONCLUSIONS
  Recreational sitting, as reflected by television/screen viewing time, is related to raised mortality and CVD risk regardless of physical activity participation. Inflammatory and metabolic risk factors partly explain this relationship.
authors.affiliation: Department of Epidemiology and Public Health, University College London, United Kingdom. e.stamatakis@ucl.ac.uk
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Stamatakis
authors.forename: Mark
authors.initials: M
authors.lastname: Hamer
authors.forename: David W
authors.initials: DW
authors.lastname: Dunstan
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood; D015992:Body Mass Index; D002097:C-Reactive Protein / Q000378:metabolism; D002318:Cardiovascular Diseases / Q000097:blood / Q000209:etiology* / Q000401:mortality*; D002784:Cholesterol / Q000097:blood; D005260:Female; D005500:Follow-Up Studies; D006306:Health Surveys / Q000379:methods; D006801:Humans; D007899:Leisure Activities; D008297:Male; D008875:Middle Aged; D009026:Mortality; D011159:Population Surveillance / Q000379:methods; D012307:Risk Factors; D057185:Sedentary Behavior; D013690:Television; D013997:Time Factors; D018910:Video Games / Q000009:adverse effects*
chemical_list: D015415:Biomarkers; D002097:C-Reactive Protein; D002784:Cholesterol