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Predictors of Physical Activity Maintenance in Older Adults with Coronary Heart Disease Julie Fleury Michael Belyea Adriana Perez
Predictors of Physical Activity Maintenance in Older Adults with Coronary Heart Disease
Julie Fleury
Michael Belyea
Adriana Perez
Background
o Maintenance of physical activity is essential to promote cardiovascular health and prevent loss of rehabilitative gains
o Despite benefits of cardiac rehabilitation, failure to maintain physical activity is a fundamental problem
o Little is known about the social contextual or motivational determinants through which physical activity is maintained following cardiac rehabilitation
Purpose
o The purpose of this study was to determine which social contextual resource and behavioral change process variables within the wellness motivation theory were significant predictors of physical activity among individuals with diagnosed coronary heart disease (CHD), who had completed a program of cardiac rehabilitation
Self-regulation
MotivationAppraisal
Regular Physical Activity
Social ContextualResources
Behavioral Change Processes
Action
Wellness Motivation Theory
Environmental
Social
Demographic
Research Design
o Prospective, longitudinal study to examine predictors of physical activity maintenance
o Measurement occurred at three time points:T0: 2 weeks post-rehabilitation programT1: 3 months post-rehabilitation programT2: 6 months post-rehabilitation program
Setting
o Cardiac Rehabilitation Centers
Serve diverse patient populations
Target urban and rural communities
Incorporate preventive services
Foster multidisciplinary focus
Participants
o English literate
o Clinically diagnosed CHD
o Graduates from monitored rehabilitation
o Clinically categorized as low risk
AACVPR
AHA
Procedures
o Recruit/screen for eligibilityo Provide informed consento Measurement
Self-report measures
Variables and Measurement: Social Contextual Resources
o Concept Measure Description
o Demographic Age, Gender, Individual
Education Characteristics
o Social resource Support Support Friends
o Environment Neighborhood Resources
resource Home Resources
Variables and Measurement:Behavioral Change Processes
o Concept Measure Description
o Motivation Index of Readiness Commitment
Appraisal Goal strategies
o Self-regulation Index of Self- Stimulus control,
Regulation Behavioral monitoring
Variables and Measurement: Action
oConcept Measure Description
o Activity type Activity mode: PA Intentional activity
o Activity frequency, Days per week Weekly minutes
duration Minutes per event
o Activity maintenance Minutes per week Sum of weekly time in minutes
Data Analysis
o Latent Growth Curve Model Mean structure provides information about:
• Average rate of change in time spent in Physical Activity (mean slope)
• Average initial time spent in Physical Activity (mean intercept)
Latent variances provide information about:
• Variability of initial time spent in Physical Activity
• Variability of rate of change in time spent in Physical Activity
Data Analysis
o Time-Invariant CovariatesGender, age, education, neighborhood
environment, home environment added as predictors of intercepts and slopes
Structural means become intercept values
Initial level and rate of change adjusted for covariates
Data Analysis
o Time-Varying Covariates Motivation Appraisal, Self-Regulation and Social
Support as Time Varying Covariates
Variables measured at 3 time points
Included as predictors of time spent in Physical Activity at each time point
Initial level and change in time spent in Physical Activity adjusted for Motivation Appraisal, Self-Regulation, and Social Support
Time-Varying and Time-Invariant Covariatesin Physical Activity Growth Curve Model
Gender Age EducNeighbor
EnvirHomeEnvir
Intercept(Initial Time
Spent)
Slope(Rate of change
Time Spent)
Activity ActivityActivity
t0 t2t1
Readiness Readiness ReadinessSelf-
RegulationSelf-
RegulationSelf-
RegulationSocial
SupportSocial
SupportSocial
Supportt0 t1 t2t0 t1 t2t0 t1 t2
Results: Sample CharacteristicsVariable Mean Std. Dev.Gender: 1=M;0=F .76 .43Age 63.57 10.25Education 15.86 3.33Neighborhood Envir 8.88 1.89Home Envir 3.45 1.84Time Spent, T0 213.26 158.17Time Spent, T1 222.65 151.35Time Spent, T2 170.97 186.45Readiness, T0 38.97 11.85Readiness, T1 36.47 15.40Readiness, T2 21.52 46.12Self-Regulation, T0 40.89 12.76Self-Regulation, T1 40.34 16.24Self-Regulation, T2 24.12 47.28Social Support, T0 20.67 33.86Social Support, T1 22.92 26.95Social Support, T2 17.76 47.09
Results: Unconditional Growth Model
Parameter: Unstan Coeff Stan Coeff Sig
Growth Parameters:
Ave intercept 220.99 1.73 0.00
Ave Slope 12.21 0.05 0.05
Intercept variance 16337.07 1.00 0.00
Slope variance 2729.27 1.00 0.05
Intercept/slope covariance -1258.44 -0.22 0.33
Results: Model including Time-Invariant Covariates and Time-Varying Covariates
Parameter: Unstan Coeff Stan Coeff Sig
Growth Parameters:
Ave intercept 49.32 0.39 0.66
Ave Slope -40.98 -0.74 0.52
Intercept variance 15692.86 0.98 0.00
Slope variance 2729.27 0.88 0.01
Results: Model including Time-Invariant Covariates and Time-Varying Covariates
Parameter: Unstan Coeff Stan Coeff Sig
Time-invariant covariates:
Gender -> Intercept 12.49 0.04 0.63
Age -> Intercept 1.03 0.08 0.36
Education -> Intercept 1.70 0.05 0.61
Neighborhood Envir -> Intercept -5.44 -0.08 0.36
Home Envir -> Intrcept 6.71 0.10 0.29
Gender -> Slope 0.03 0.00 0.99
Age -> Slope 0.63 0.12 0.28
Education -> Slope -0.77 -0.05 0.66
Neighborhood Envir -> Slope 5.79 0.20 0.05
Home Envir -> Slope -8.14 -0.27 0.02
Results: Model including Time-Invariant Covariates and Time-Varying Covariates
Parameter Unstan Coeff Stan Coeff Sig
Time-varying covariates:
Readiness T0 -> Time Spent T0 -1.59 -0.06 0.37
Self-Regulation T0 -> Time Spent T0 2.86 0.14 0.04
Social Support T0 -> Time Spent T0 1.14 0.14 0.02
Readiness T1 -> Time Spent T1 -0.07 0.00 0.96
Self-Regulation T1 -> Time Spent T1 2.34 0.11 0.05
Social Support T1 -> Time Spent T1 -0.01 0.00 0.98
Readiness T2 -> Time Spent T2 -1.68 -0.06 0.43
Self-Regulation T2 -> Time Spent T2 3.25 0.16 0.05
Social Support T2 -> Time Spent T2 0.13 0.02 0.81
Summary
o Moderate level of time spent in physical activity following a cardiac rehabilitation program A small drop in time spent over 6 months
o Significant differences in the initial level of time spent and rate of change over time
o Demographic variables did not account for variability in initial levels or rate of change over time
Summary
o Neighborhood environment was positively related to the rate of changeHigher perceived neighborhood resources
was related to more physical activityo Home environment was negatively related to
change over 6 monthsHigher perceived resources resulted in less
physical activity
Summary
o Changes in social support were positively related to time spent in physical activity
o Changes in self-regulation were positively related to time spent in physical activity
Conclusions
o Data provide a basis for programmatic research, and guide development of theory-based interventions to foster the maintenance of physical activity among patients with diagnosed CHD
o Latent growth curve analysis provides important information about positive and negative shifts in physical activity following cardiac rehabilitation
o Data support the need for a multi-level approach to promoting physical activity maintenance, including environmental resources, engagement in social interactions, and skill building in self-regulation
