title: Traditional and Emerging Lifestyle Risk Behaviors and All-Cause Mortality in Middle-Aged and Older Adults: Evidence from a Large Population-Based Australian Cohort.
abstract: BACKGROUND
  Lifestyle risk behaviors are responsible for a large proportion of disease burden worldwide. Behavioral risk factors, such as smoking, poor diet, and physical inactivity, tend to cluster within populations and may have synergistic effects on health. As evidence continues to accumulate on emerging lifestyle risk factors, such as prolonged sitting and unhealthy sleep patterns, incorporating these new risk factors will provide clinically relevant information on combinations of lifestyle risk factors.
  
  
  RESULTS
  Using data from a large Australian cohort of middle-aged and older adults, this is the first study to our knowledge to examine a lifestyle risk index incorporating sedentary behavior and sleep in relation to all-cause mortality. Baseline data (February 2006- April 2009) were linked to mortality registration data until June 15, 2014. Smoking, high alcohol intake, poor diet, physical inactivity, prolonged sitting, and unhealthy (short/long) sleep duration were measured by questionnaires and summed into an index score. Cox proportional hazards analysis was used with the index score and each unique risk combination as exposure variables, adjusted for socio-demographic characteristics. During 6 y of follow-up of 231,048 participants for 1,409,591 person-years, 15,635 deaths were registered. Of all participants, 31.2%, 36.9%, 21.4%, and 10.6% reported 0, 1, 2, and 3+ risk factors, respectively. There was a strong relationship between the lifestyle risk index score and all-cause mortality. The index score had good predictive validity (c index = 0.763), and the partial population attributable risk was 31.3%. Out of all 96 possible risk combinations, the 30 most commonly occurring combinations accounted for more than 90% of the participants. Among those, combinations involving physical inactivity, prolonged sitting, and/or long sleep duration and combinations involving smoking and high alcohol intake had the strongest associations with all-cause mortality. Limitations of the study include self-reported and under-specified measures, dichotomized risk scores, lack of long-term patterns of lifestyle behaviors, and lack of cause-specific mortality data.
  
  
  CONCLUSIONS
  Adherence to healthy lifestyle behaviors could reduce the risk for death from all causes. Specific combinations of lifestyle risk behaviors may be more harmful than others, suggesting synergistic relationships among risk factors.
authors.affiliation: Prevention Research Collaboration, Sydney School of Public Health, University of Sydney, Camperdown, New South Wales, Australia.|Charles Perkins Centre, University of Sydney, Camperdown, New South Wales, Australia.
authors.forename: Ding
authors.initials: D
authors.lastname: Ding
authors.affiliation: Prevention Research Collaboration, Sydney School of Public Health, University of Sydney, Camperdown, New South Wales, Australia.|George Institute for Global Health, Sydney, New South Wales, Australia.
authors.forename: Kris
authors.initials: K
authors.lastname: Rogers
authors.affiliation: Prevention Research Collaboration, Sydney School of Public Health, University of Sydney, Camperdown, New South Wales, Australia.|Department of Public and Occupational Health, EMGO Institute for Health and Care Research, VU University Medical Centre, Amsterdam, the Netherlands.
authors.forename: Hidde
authors.initials: H
authors.lastname: van der Ploeg
authors.affiliation: Charles Perkins Centre, University of Sydney, Camperdown, New South Wales, Australia.|Exercise and Sports Science, Faculty of Health Sciences, University of Sydney, Camperdown, New South Wales, Australia.
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Stamatakis
authors.affiliation: Prevention Research Collaboration, Sydney School of Public Health, University of Sydney, Camperdown, New South Wales, Australia.|Charles Perkins Centre, University of Sydney, Camperdown, New South Wales, Australia.
authors.forename: Adrian E
authors.initials: AE
authors.lastname: Bauman
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008019:Life Style; D008297:Male; D008875:Middle Aged; D009026:Mortality; D009517:New South Wales / Q000453:epidemiology; D015995:Prevalence; D011446:Prospective Studies; D012309:Risk-Taking; D057185:Sedentary Behavior; D012890:Sleep