Dose-response associations between accelerometry measured physical activity and sedentary time and all cause mortality: systematic review and harmonised meta-analysisBMJ 2019; 366 doi: https://doi.org/10.1136/bmj.l4570 (Published 21 August 2019) Cite this as: BMJ 2019;366:l4570
- Ulf Ekelund, professor12,
- Jakob Tarp, postdoctoral student1,
- Jostein Steene-Johannessen, associate professor1,
- Bjørge H Hansen, associate professor1,
- Barbara Jefferis, senior lecturer3,
- Morten W Fagerland, statistician14,
- Peter Whincup, professor5,
- Keith M Diaz, assistant professor6,
- Steven P Hooker, professor7,
- Ariel Chernofsky, doctoral student8,
- Martin G Larson, professor8,
- Nicole Spartano, assistant professor9,
- Ramachandran S Vasan, professor10,
- Ing-Mari Dohrn, postdoctoral student11,
- Maria Hagströmer, associate professor1112,
- Charlotte Edwardson, senior lecturer1314,
- Thomas Yates, professor1314,
- Eric Shiroma, scientist15,
- Sigmund A Anderssen, professor1,
- I-Min Lee, professor1617
- 1Department of Sports Medicine, Norwegian School of Sport Sciences, PO Box 4014, Ullevål Stadion, 0806 Oslo, Norway
- 2Department of Chronic Diseases and Ageing, Norwegian Institute of Public Health, Oslo, Norway
- 3Department of Primary Care and Population Health, Institute of Epidemiology and Health Care, University College London. London, UK
- 4Oslo Centre for Biostatistics and Epidemiology, Research Support Services, Oslo University Hospital, Oslo, Norway
- 5Population Health Research Institute, St George’s, University of London, London, UK
- 6Center for Behavioral Cardiovascular Health, Department of Medicine, Columbia University Medical Center, New York, USA
- 7College of Health and Human Services, San Diego State University, San Diego, CA, USA
- 8Department of Biostatistics, Boston University School of Public Health, Boston, MA, USA
- 9Department of Endocrinology, Diabetes, Nutrition and Weight Management, Boston University School of Medicine, Boston, MA, USA
- 10Departments of Medicine and Epidemiology, Boston University School of Medicine and Boston University School of Public Health, Boston, MA, USA
- 11Department of Neurobiology, Care Sciences and Society, Aging Research Center, Karolinska Institutet, Stockholm, Sweden
- 12Function area Occupational Therapy and Physiotherapy, Allied Health Professionals, Karolinska University Hospital, Stockholm, Sweden
- 13Diabetes Research Centre, College of Life Sciences, University of Leicester, Leicester, UK
- 14NIHR Leicester Biomedical Research Centre, University of Leicester and University Hospitals of Leicester NHS Trust, Leicester, UK
- 15Neuro-epidemiology Section, National Institute of Ageing, National Institutes of Health, Bethesda, MD, USA
- 16Department of Medicine, Brigham and Women’s Hospital and Harvard Medical School, Boston, MA, USA
- 17Department of Epidemiology, Harvard T.H. Chan School of Public Health, Boston, MA, USA
- Correspondence to: U Ekelund @ulf_ekelund on Twitter) (or
- Accepted 27 June 2019
Objective To examine the dose-response associations between accelerometer assessed total physical activity, different intensities of physical activity, and sedentary time and all cause mortality.
Design Systematic review and harmonised meta-analysis.
Data sources PubMed, PsycINFO, Embase, Web of Science, Sport Discus from inception to 31 July 2018.
Eligibility criteria Prospective cohort studies assessing physical activity and sedentary time by accelerometry and associations with all cause mortality and reported effect estimates as hazard ratios, odds ratios, or relative risks with 95% confidence intervals.
Data extraction and analysis Guidelines for meta-analyses and systematic reviews for observational studies and PRISMA guidelines were followed. Two authors independently screened the titles and abstracts. One author performed a full text review and another extracted the data. Two authors independently assessed the risk of bias. Individual level participant data were harmonised and analysed at study level. Data on physical activity were categorised by quarters at study level, and study specific associations with all cause mortality were analysed using Cox proportional hazards regression analyses. Study specific results were summarised using random effects meta-analysis.
Main outcome measure All cause mortality.
Results 39 studies were retrieved for full text review; 10 were eligible for inclusion, three were excluded owing to harmonisation challenges (eg, wrist placement of the accelerometer), and one study did not participate. Two additional studies with unpublished mortality data were also included. Thus, individual level data from eight studies (n=36 383; mean age 62.6 years; 72.8% women), with median follow-up of 5.8 years (range 3.0-14.5 years) and 2149 (5.9%) deaths were analysed. Any physical activity, regardless of intensity, was associated with lower risk of mortality, with a non-linear dose-response. Hazards ratios for mortality were 1.00 (referent) in the first quarter (least active), 0.48 (95% confidence interval 0.43 to 0.54) in the second quarter, 0.34 (0.26 to 0.45) in the third quarter, and 0.27 (0.23 to 0.32) in the fourth quarter (most active). Corresponding hazards ratios for light physical activity were 1.00, 0.60 (0.54 to 0.68), 0.44 (0.38 to 0.51), and 0.38 (0.28 to 0.51), and for moderate-to-vigorous physical activity were 1.00, 0.64 (0.55 to 0.74), 0.55 (0.40 to 0.74), and 0.52 (0.43 to 0.61). For sedentary time, hazards ratios were 1.00 (referent; least sedentary), 1.28 (1.09 to 1.51), 1.71 (1.36 to 2.15), and 2.63 (1.94 to 3.56).
Conclusion Higher levels of total physical activity, at any intensity, and less time spent sedentary, are associated with substantially reduced risk for premature mortality, with evidence of a non-linear dose-response pattern in middle aged and older adults.
Systematic review registration PROSPERO CRD42018091808.
Contributors: UE and I-ML conceived and designed the study. All authors acquired the data. UE, JT, BHH, JS-J, SAA, BJ, and I-ML analysed and interpreted the pooled data. UE and JT drafted the manuscript. All authors critically revised the manuscript for important intellectual content. MWF and JT carried out the statistical analysis of the pooled data. UE is the guarantor. The corresponding author attests that all listed authors meet authorship criteria and that no others meeting the criteria have been omitted.
Funding: There was no specific funding for this work. The individual studies contributing to this harmonised meta-analysis were funded: the ABC-study was funded by Stockholm County Council, Swedish National Centre for Research in Sports, and project ALPHA, which received funding from the European Union in the framework of the Public Health Programme and Folksam Research Foundation, Sweden; the British Regional Heart Study was funded by project and programme grants from the British Heart Foundation (PG/13/86/30546 and RG/13/16/30528); the Framingham Heart Study’s data collection and analysis was funded by the National Institutes of Health, National Heart, Lung, and Blood Institute (NHLBI)-N01-HC25195; Health and Human Services (N268201500001I; R01-AG047645; R01-HL131029); and American Heart Association (15GPSGC24800006); the Norwegian National Physical Activity Surveillance Study was supported by the Norwegian Directorate for Public Health and the Norwegian School of Sport Sciences. JT is funded by the Research Council of Norway (249932/F20); the REGARDS study was supported by a cooperative agreement U01-NS041588 and investigator initiated grant R01-NS061846 from the National Institute of Neurological Disorders and Stroke of the National Institutes of Health. Additional funding was provided by an unrestricted research grant from the Coca-Cola Company; the Walking Away from type 2 Diabetes study was supported by the National Institute for Health Research (NIHR) Collaboration for Leadership in Applied Health Research and Care East Midlands; the Women’s Health Study was funded by the National Institutes of Health (NIH) grants; CA154647, CA047988, CA182913, HL043851, HL080467, and HL099355. The funders of the individual studies had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; and preparation, review, or approval of the manuscript.
Competing interests: All authors have completed the ICMJE uniform disclosure form and declare: no support from any organisation for the submitted work; no financial relationships with any organisations that might have an interest in the submitted work in the previous three years; no other relationships or activities that could appear to have influenced the submitted work.
Ethical approval: Not required.
Data sharing: The study specific summary data included in the meta-analysis can be obtained from the corresponding author; firstname.lastname@example.org
The lead author (UE) affirms that the manuscript is an honest, accurate, and transparent account of the study being reported; that no important aspects of the study have been omitted; and that any discrepancies from the study as planned (and, if relevant, registered) have been explained.
This is an Open Access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/.