Correlates of General and Domain-Specific Sitting Time among Older Adults

A Cross-Sectional Examination of Patterns of Sedentary Behavior and Cardiometabolic Risk in Community-Dwelling Adults Aged 55 Years and Older

Introduction

Sedentary behavior (SB) is highly prevalent among older adults, with more than 25% engaging in 6 hours or more of SB daily. SB has been associated with several cardiometabolic biomarkers in younger adults; however, there is a paucity of research in older populations. This study examined associations between patterns of SB and cardiometabolic biomarkers in community-dwelling adults aged 55 years and older.

Methods

Data were drawn from a convenience sample of 54 community-dwelling individuals (12 males, 42 females; mean age = 72.6 ± 6.8 years, range = 56–89 years). Cardiometabolic biomarkers assessed included systolic (SBP) and diastolic blood pressure (DBP), body mass index, waist circumference, and fasting blood glucose and cholesterol parameters. SB was assessed via accelerometry over a 7-day period, and measures included daily time in SB, number and length of sedentary bouts, the number and length of breaks between sedentary bouts, moderate-to-vigorous physical activity (MVPA), and light physical activity (LPA). Associations between the SB measures and each cardiometabolic risk factor were examined using separate stepwise multiple regression models, controlling for sex, MVPA, and accelerometer wear time. Isotemporal substitution models were used to examine the change in cardiometabolic outcomes when SB is replaced by an equal duration of either LPA or MVPA.

Results

Adjusted regression analyses showed that daily sedentary time was positively associated with DBP (β = 0.052, ∆R² = 0.112, p = 0.022) and inversely associated with HDL cholesterol (β = −0.111, ∆R² = 0.121, p = 0.039). Sedentary bout length was also associated with DBP and HDL cholesterol (β = 0.575, ∆R² = 0.152, p = 0.007; β = −1.529, ∆R² = 0.196, p = 0.007, respectively). Replacement of 10 minutes of SB a day with LPA was associated with improved DBP and HDL cholesterol (p ≤ 0.05). No other significant associations (p ≤ 0.05) were found.

Conclusion

Sitting for prolonged periods of time without interruption is unfavorably associated with DBP and HDL cholesterol. Prospective studies should identify causal relationships and observe specific changes in cardiometabolic profiles in older populations.

The impact of physical activity and sedentary behaviors on frailty levels

Heterogeneity in aging can be explained by frailty. Lifestyle behaviors such as physical activity can help manage frailty levels. Conversely, sedentary behaviours are associated with frailty independently of physical activity. Here, we summarize epidemiological and clinical trial evidence concerning the impact of physical activity and sedentary behaviors on frailty levels. We also analysed the National Health and Nutrition Examination Survey (NHANES) data to describe physical activity and sedentary behavior accumulation patterns across frailty levels and their impact on mortality risk. The few prospective and intervention studies demonstrate that higher physical activity levels are associated with a lower incidence of frailty. There are no interventions published which limit sedentary behaviors to manage frailty. Using the NHANES data we demonstrate that individuals are less likely to meet physical activity guidelines and are more likely to accumulate sedentary time in prolonged bouts. Prolonged sedentary bouts and total sedentary time were associated with a higher mortality risk in frail individuals but not in the fit group. Non-bouted sedentary time was not associated with mortality risk. Our review and novel data suggest that there is a need for more intervention studies which focus on increasing physical activity or minimizing sedentary time to manage frailty levels.

Is Cannabis Use Associated with Sedentary Behavior during Leisure Time? A Study in Canada, 2011-2012

BACKGROUND

Sedentary behavior, defined as lying or sitting, is a global health concern. As researchers continue to identify modern-day risk factors for sedentary behavior, few have explored the role of illicit drug use.

OBJECTIVE

To examine the association between leisure-time sedentary behavior and cannabis use, in adolescents and adults.

METHODS

We conducted a cross-sectional study relating cannabis use to total leisure-time sedentary behavior (hr/wk using the computer, playing video games, watching television or videos, and reading for leisure) using data from the 2011-2012 Canadian Community Health Survey (CCHS), a population-based survey of Canadians age ≥12 years. Analyses were possible for 48,240 respondents in Saskatchewan, Ontario, and Nunavut who reported on sedentary behavior. We used logistic regression modeling to relate frequency of cannabis use (never, occasional, heavy) to high-risk sedentary behavior (<35 versus ≥35 hr/wk) overall and stratified by sex, age, and rural location.

RESULTS

Approximately 80% of respondents were ≥25 years old. In the fully-adjusted model, the odds of ≥35 hr/wk of sedentary behavior were 80% higher for heavy cannabis users versus never users (OR = 1.8, 95% CI: 1.4-2.3); in occasional cannabis users, the odds were 30% higher (OR = 1.3, 95% CI: 1.1-1.5). In stratified analyses, odds ratios were statistically significant among adults age 25-44 years and people living in nonrural settings. Conclusions/Importance: Our findings support dual lifestyle interventions targeting heavy cannabis use and excessive sedentary behavior simultaneously. Moreover, leisure-time sedentary behavior should be considered as a covariate in future epidemiologic models relating cannabis to health.

Leisure-time Physical Activity and Sedentary Behaviour in Older People: The Influence of Sport Involvement on Behaviour Patterns in Later Life

Given the dramatic demographic change underway in most industrialized nations, the health of older adults is a major concern, particularly given the prevalence of sedentary behaviours and physical inactivity among ageing populations. Researchers have suggested sport participation in later life promotes other health-related behaviours, however, these relationships are poorly understood. It is possible for individuals to be classified as sufficiently active and still spend most of their day involved in sedentary pursuits. Moreover, there is little information on older sport participants' use of time compared to leisurely active or inactive peers and whether type of physical activity involvement is associated with differences in older adults' behaviour patterns. With this in mind, data from 1,723 respondents (65 years and older) who completed the sport module of the 2010 Canadian General Social Survey-Time Use were used to investigate the influence of physical activity involvement (competitive sport vs. non-competitive sport vs. physically active leisure vs. inactivity) on time spent in leisure-time physical activity and sedentary behaviours. Results indicated that competitive sport participants spent less time engaging in sedentary behaviours compared to the physically active leisure or inactive respondents; however, sport participants (both competitive and non-competitive) also spent less time engaging in leisure-time physical activities than the physically active leisure group. Implications of these findings to assumptions related to the activity levels of older sport participants, suggestions for future research, and considerations for sport-related interventions aimed at enhancing health in older adulthood are discussed.