physical activity of baby boomers compared to older and younger generations in canada:
DESCRIPTION
Physical activity of baby boomers compared to older and younger generations in Canada: An age-period-cohort analysis. Mayilee Canizares , Elizabeth Badley , Monique Gignac , Sheilah Hogg-Johnson, and Anthony Perruccio. University Health Network, Toronto, Canada, - PowerPoint PPT PresentationTRANSCRIPT
Physical activity of baby boomers compared to older and younger
generations in Canada: An age-period-cohort analysis
Mayilee Canizares, Elizabeth Badley, Monique Gignac, Sheilah Hogg-Johnson, and Anthony Perruccio
University Health Network, Toronto, Canada,
University of Toronto, Toronto, Canada,
Institute for Work and Health, Toronto, Canada
Canadian Public Health AssociationMay 2014
Background
Physical activity has well-documented health benefits.
Studies using repeated cross-sectional surveys indicate that participation in leisure time physical activities (LTPA) has increased over time.
Also being sedentary in usual activities has increased over time.
Cross-sectional studies suggest that participation in LTPA decline with age and is also lower in younger birth cohorts.
It is not well documented if these changes in LTPA over time differ by birth cohorts.
To examine birth cohort and/or period effects (secular changes) in the age-trajectories of LTPA over 16 years among Canadian adults.
To examine whether the age-trajectories of LTPA were associated with changes in usual activities after controlling for sex, educational attainment, income, and BMI.
Objectives
What are age, period, and cohort effects?
Age effects are the consequences of growing older. How things change with age irrespective of birth
cohort and calendar timePeriod effects are the consequences of influences that vary through time.
Changes that affect the entire population irrespective of age and birth cohort (e.g. new treatments, environmental disasters, changes in policies, the economy etc.)
Cohort effects are the consequences of being born and growing up at different times.
Changes according to year of birth, irrespective of age and calendar time
Blackwell encyclopedia of sociology, Ed, Ritzer G. 2007
Data Sources
Canadian National Population Health Survey (NPHS) National representative longitudinal household
survey Biennial interviews from 1994/95 to 2010/11 9 cycles spanning 16 years
Sample of 8,570 participants in one of the birth cohorts
Year of Birth
Age at baseline
World War II (WW) 1935 – 1944 50-59Older baby boomer (OBB) 1945 – 1954 40-49Younger baby boomer (YBB): 1955 – 1964 30-39Generation X (GenX): 1965 – 1974 20-29
1. Usual activities ‘Thinking back over the past 3 months, which of the following best describes your usual activities or work habits?’‘Sit during the day and don’t walk much’, ‘Stand or walk quite a lot’, ‘Lift/carry light loads’ , ‘Heavy work or carry heavy loads’
2. Leisure time physical activity(LTPA): at least moderateModerate active: >1.5 kcal/kg/day1
3. Walking/cycling for commuting and errands (WCCE): at least moderate
‘In a typical week in the past 3 months, how many hours did you usually spend walking (cycling) to work or school or while doing errands?’
1 Katzmarzyk and Tremblay (2007)
Dimensions of physical activity
Statistical Analysis
Multilevel growth models
Age-trajectory of LTPA by cohort: o Not including periodo Including period
Added usual activities to the APC model of LTPA previously fitted, controlling for sex, education, income, and BMI
Results
GenX YBB OBB WW0
10
20
30
40
50
1994 2010
Prop
ortio
n (%
)Leisure time physical activity
Predicted age- trajectory by cohort
LTPA: age trajectories by cohort
0
10
20
30
40
50
60
70
GenX YBBOBB WW
Age (years)
Pred
icted
pro
porti
on (%
)
Cohort effect: p<0.0001Age effect: p<0.0001Period effect: -
Predicted age- trajectory by cohort holding period constantPredicted age- trajectory by cohort
LTPA: age trajectories by cohort
0
10
20
30
40
50
60
70
GenX YBBOBB WW
Age (years)
Pred
icted
pro
porti
on (%
)
Cohort effect: p=0.015Age effect: p<0.0001Period effect: p<0.0001
Usual activities
GenX YBB OBB WW0
10
20
30
40
50
1994 2010
Prop
ortio
n (%
)
Leisure time physical activity : effect of changes in usual activities
Odd Ratio (95% CI)
Usual activities: sedentary
0.73**
(0.71 – 0.74)
**Significant at p<0.001. Models included age terms, cohort, period. aAlso included sex, education, income and BMI
Further analysis show a significant interaction between usual activities and sex
0
20
40
60
80
Pred
icted
LTPA
(%)
0
20
40
60
80
Pred
icte
d LT
PA (%
)
0
20
40
60
80
Pred
icted
LTPA
(%)
0
20
40
60
80Pr
edic
ted
LTPA
(%)
GenX YBB
OBB WWII
Leisure time physical activity : by categories of usual activities by sex
Solid/Dashed: Not Sedentary/ Sedentary in usual day
Dark/Light: Women/Men
Physical activity measured in the NPHS Self-reported nature of the data Attrition due to drop-outs and mortality,
particularly in the older cohort
Limitations
In all cohorts, individuals are increasingly participating in LTPA as they grow older and this growth is due to period effecto health promotion initiatives have been somewhat
successful Members of the younger cohorts are more likely to be
physically active during leisure time than their older counterparts
Generally, those who are sedentary in their usual activities are less likely to participate in LTPA o particularly women in all cohorts and men in the
two oldest cohorts The results indicate that efforts to address LTPA also
need to take into account usual activities
Summary and Conclusions
Canadian Institutes of Health Research
Operating Grant - Secondary Analysis of Databases
‘In sickness or in health? How well are the baby boomers aging compared to older generations: an analysis of age, period and cohort effects.’
P.I. Elizabeth Badley
Acknowledgements
0
5
10
15
20
25
30
Age (years)
Pred
icte
d pr
opor
tion
(%)
Predicted age- trajectory by cohort
WCE: age trajectories by cohort
WCE: age trajectories by cohort
0
5
10
15
20
25
30
Age (years)
Pred
icte
d pr
opor
tion
(%)
Predicted age- trajectory by cohort holding period constantPredicted age- trajectory by cohort
20 24 28 32 36 40 44 48 52 56 60 64 68 72 760
5
10
15
20
25
30
Age (years)
Pred
icted
pro
porti
on (%
)
Predicted age- trajectory by cohort
Usually sedentary: age trajectories by cohort
20 24 28 32 36 40 44 48 52 56 60 64 68 72 760
5
10
15
20
25
30
Age (years)
Pred
icted
pro
porti
on (%
)
Predicted age- trajectory by cohort holding period constantPredicted age- trajectory by cohort
Usually sedentary: age trajectories by cohort