Accelerometer-measured physical activity and sedentary time in a cohort of US adults followed for up to 13 years: the influence of removing early follow-up on associations with mortality
Abstract Background Observational studies linking physical activity with mortality are susceptible to reverse causation bias from undiagnosed and prevalent diseases. Researchers often attempt to deal with reverse causation bias by excluding deaths occurring within the first 1 or 2 years from the ana...
Main Authors: | , , , , , |
---|---|
Format: | Article |
Language: | English |
Published: |
BMC
2020-03-01
|
Series: | International Journal of Behavioral Nutrition and Physical Activity |
Subjects: | |
Online Access: | http://link.springer.com/article/10.1186/s12966-020-00945-4 |
id |
doaj-180fad2acd9f4d8c972089a38f550be8 |
---|---|
record_format |
Article |
spelling |
doaj-180fad2acd9f4d8c972089a38f550be82020-11-25T02:51:11ZengBMCInternational Journal of Behavioral Nutrition and Physical Activity1479-58682020-03-011711810.1186/s12966-020-00945-4Accelerometer-measured physical activity and sedentary time in a cohort of US adults followed for up to 13 years: the influence of removing early follow-up on associations with mortalityJakob Tarp0Bjørge Herman Hansen1Morten Wang Fagerland2Jostein Steene-Johannessen3Sigmund Alfred Anderssen4Ulf Ekelund5Department of Sports Medicine, Norwegian School of Sports SciencesDepartment of Sports Medicine, Norwegian School of Sports SciencesDepartment of Sports Medicine, Norwegian School of Sports SciencesDepartment of Sports Medicine, Norwegian School of Sports SciencesDepartment of Sports Medicine, Norwegian School of Sports SciencesDepartment of Sports Medicine, Norwegian School of Sports SciencesAbstract Background Observational studies linking physical activity with mortality are susceptible to reverse causation bias from undiagnosed and prevalent diseases. Researchers often attempt to deal with reverse causation bias by excluding deaths occurring within the first 1 or 2 years from the analysis, but it is unclear if excluding deaths within this time-frame is sufficient to remove bias. Methods We examined associations between total and intensity-specific physical activity and sedentary time with all-cause mortality in a prospective cohort of 3542 individuals from the 2003–2006 NHANES cycles. In order to yield measures of association hypothesized as minimally influenced by reverse causation bias the primary analysis excluded individuals with < 5 years of follow-up. Accelerometer-measured physical activity was linked with recently updated vital status from the National Death Index with a median follow-up of 10.8 years. Results Hazard ratios (95% confidence intervals) were 0.74 (0.53, 1.04), 0.52 (0.37, 0.73), and 0.61 (0.38, 1.01) for ascending quartiles of total physical activity against the least active reference. Hazard ratios for ascending moderate-to-vigorous physical activity quartiles against the reference were 0.67 (0.47, 1.96), 0.67 (0.47, 0.95), and 0.68 (0.39, 1.18). Associations for light intensity physical activity and sedentary time were smaller in magnitude and all confidence intervals included unity. Total activity and moderate-to-vigorous physical activity hazard ratios from analyses only excluding deaths within the first 2 years were inflated by 13 and 26% relative to analysis restricted to ≥5 years of follow-up. Conclusions The pattern of associations suggested total physical activity and moderate-to-vigorous physical activity were associated with lower mortality after more than 10 years of follow-up and excluding the first 5 years of observation time to minimize the impact of reverse causation bias. Excluding deaths within the first 2 years appeared insufficient to minimize the impact of reserve causation bias.http://link.springer.com/article/10.1186/s12966-020-00945-4Cohort studyEpidemiologyExerciseLeisure activity |
collection |
DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
Jakob Tarp Bjørge Herman Hansen Morten Wang Fagerland Jostein Steene-Johannessen Sigmund Alfred Anderssen Ulf Ekelund |
spellingShingle |
Jakob Tarp Bjørge Herman Hansen Morten Wang Fagerland Jostein Steene-Johannessen Sigmund Alfred Anderssen Ulf Ekelund Accelerometer-measured physical activity and sedentary time in a cohort of US adults followed for up to 13 years: the influence of removing early follow-up on associations with mortality International Journal of Behavioral Nutrition and Physical Activity Cohort study Epidemiology Exercise Leisure activity |
author_facet |
Jakob Tarp Bjørge Herman Hansen Morten Wang Fagerland Jostein Steene-Johannessen Sigmund Alfred Anderssen Ulf Ekelund |
author_sort |
Jakob Tarp |
title |
Accelerometer-measured physical activity and sedentary time in a cohort of US adults followed for up to 13 years: the influence of removing early follow-up on associations with mortality |
title_short |
Accelerometer-measured physical activity and sedentary time in a cohort of US adults followed for up to 13 years: the influence of removing early follow-up on associations with mortality |
title_full |
Accelerometer-measured physical activity and sedentary time in a cohort of US adults followed for up to 13 years: the influence of removing early follow-up on associations with mortality |
title_fullStr |
Accelerometer-measured physical activity and sedentary time in a cohort of US adults followed for up to 13 years: the influence of removing early follow-up on associations with mortality |
title_full_unstemmed |
Accelerometer-measured physical activity and sedentary time in a cohort of US adults followed for up to 13 years: the influence of removing early follow-up on associations with mortality |
title_sort |
accelerometer-measured physical activity and sedentary time in a cohort of us adults followed for up to 13 years: the influence of removing early follow-up on associations with mortality |
publisher |
BMC |
series |
International Journal of Behavioral Nutrition and Physical Activity |
issn |
1479-5868 |
publishDate |
2020-03-01 |
description |
Abstract Background Observational studies linking physical activity with mortality are susceptible to reverse causation bias from undiagnosed and prevalent diseases. Researchers often attempt to deal with reverse causation bias by excluding deaths occurring within the first 1 or 2 years from the analysis, but it is unclear if excluding deaths within this time-frame is sufficient to remove bias. Methods We examined associations between total and intensity-specific physical activity and sedentary time with all-cause mortality in a prospective cohort of 3542 individuals from the 2003–2006 NHANES cycles. In order to yield measures of association hypothesized as minimally influenced by reverse causation bias the primary analysis excluded individuals with < 5 years of follow-up. Accelerometer-measured physical activity was linked with recently updated vital status from the National Death Index with a median follow-up of 10.8 years. Results Hazard ratios (95% confidence intervals) were 0.74 (0.53, 1.04), 0.52 (0.37, 0.73), and 0.61 (0.38, 1.01) for ascending quartiles of total physical activity against the least active reference. Hazard ratios for ascending moderate-to-vigorous physical activity quartiles against the reference were 0.67 (0.47, 1.96), 0.67 (0.47, 0.95), and 0.68 (0.39, 1.18). Associations for light intensity physical activity and sedentary time were smaller in magnitude and all confidence intervals included unity. Total activity and moderate-to-vigorous physical activity hazard ratios from analyses only excluding deaths within the first 2 years were inflated by 13 and 26% relative to analysis restricted to ≥5 years of follow-up. Conclusions The pattern of associations suggested total physical activity and moderate-to-vigorous physical activity were associated with lower mortality after more than 10 years of follow-up and excluding the first 5 years of observation time to minimize the impact of reverse causation bias. Excluding deaths within the first 2 years appeared insufficient to minimize the impact of reserve causation bias. |
topic |
Cohort study Epidemiology Exercise Leisure activity |
url |
http://link.springer.com/article/10.1186/s12966-020-00945-4 |
work_keys_str_mv |
AT jakobtarp accelerometermeasuredphysicalactivityandsedentarytimeinacohortofusadultsfollowedforupto13yearstheinfluenceofremovingearlyfollowuponassociationswithmortality AT bjørgehermanhansen accelerometermeasuredphysicalactivityandsedentarytimeinacohortofusadultsfollowedforupto13yearstheinfluenceofremovingearlyfollowuponassociationswithmortality AT mortenwangfagerland accelerometermeasuredphysicalactivityandsedentarytimeinacohortofusadultsfollowedforupto13yearstheinfluenceofremovingearlyfollowuponassociationswithmortality AT josteinsteenejohannessen accelerometermeasuredphysicalactivityandsedentarytimeinacohortofusadultsfollowedforupto13yearstheinfluenceofremovingearlyfollowuponassociationswithmortality AT sigmundalfredanderssen accelerometermeasuredphysicalactivityandsedentarytimeinacohortofusadultsfollowedforupto13yearstheinfluenceofremovingearlyfollowuponassociationswithmortality AT ulfekelund accelerometermeasuredphysicalactivityandsedentarytimeinacohortofusadultsfollowedforupto13yearstheinfluenceofremovingearlyfollowuponassociationswithmortality |
_version_ |
1724735775521636352 |