Domain-specific physical activity and sedentary behaviour in relation to colon and rectal cancer risk: a systematic review and meta-analysis

The Physical Activity and Cancer Control (PACC) framework: update on the evidence, guidelines, and future research priorities

BACKGROUND

We proposed the Physical Activity and Cancer Control (PACC) framework in 2007 to help organise, focus, and stimulate research on physical activity in eight cancer control categories: prevention, detection, treatment preparation/coping, treatment coping/effectiveness, recovery/rehabilitation, disease prevention/health promotion, palliation, and survival.

METHODS

This perspective paper provides a high-level overview of the scientific advances in physical activity research across cancer control categories, summarises current guidelines, updates the PACC framework, identifies remaining and emerging knowledge gaps, and provides future research directions.

RESULTS

Many scientific advances have been made that are reflected in updated physical activity guidelines for six of the cancer control categories apart from detection and palliation. Nevertheless, the minimal and optimal type, dose, and timing of physical activity across cancer control categories remain unknown, especially for the understudied population subgroups defined by cancer type, age, race/ethnicity, and resource level of regions/countries.

CONCLUSION

To achieve the full benefit of physical activity in cancer control, future research should use innovative study designs that include diverse at-risk populations and understudied cancer sites. Additionally, effective behaviour change strategies are needed to increase physical activity levels across populations that use implementation science to accelerate the translation from evidence generation into practical, real-world interventions.

Colorectal Cancer: Epidemiology, Risk Factors, and Prevention

Colorectal cancer (CRC) is the third most common cancer and the second most common cause of cancer mortality worldwide. There are disparities in the epidemiology of CRC across different populations, most probably due to differences in exposure to lifestyle and environmental factors related to CRC. Prevention is the most effective method for controlling CRC. Primary prevention includes determining and avoiding modifiable risk factors (e.g., alcohol consumption, smoking, and dietary factors) as well as increasing protective factors (e.g., physical activity, aspirin). Further studies, especially randomized, controlled trials, are needed to clarify the association between CRC incidence and exposure to different risk factors or protective factors. Detection and removal of precancerous colorectal lesions is also an effective strategy for controlling CRC. Multiple factors, both at the individual and community levels (e.g., patient preferences, availability of screening modalities, costs, benefits, and adverse events), should be taken into account in designing and implementing CRC screening programs. Health policymakers should consider the best decision in identifying the starting age and selection of the most effective screening strategies for the target population. This review aims to present updated evidence on the epidemiology, risk factors, and prevention of CRC.

Associations between transport modes and site-specific cancers: a systematic review and meta-analysis

BACKGROUND

Physical inactivity is a global public health problem. A practical solution would be to build physical activity into the daily routine by using active modes of transport. Choice of transport mode can influence cancer risk through their effects on levels of physical activity, sedentary time, and environmental pollution. This review synthesizes existing evidence on the associations of specific transport modes with risks of site-specific cancers.

METHODS

Relevant literature was searched in PubMed, Embase, and Scopus from 1914 to 17th February 2023. For cancer sites with effect measures available for a specific transport mode from two or more studies, random effects meta-analyses were performed to pool relative risks (RR) comparing the highest vs. lowest activity group as well as per 10 Metabolic Equivalent of Task (MET) hour increment in transport-related physical activity per week (∼150 min of walking or 90 min of cycling).

RESULTS

27 eligible studies (11 cohort, 15 case-control, and 1 case-cohort) were identified, which reported the associations of transport modes with 10 site-specific cancers. In the meta-analysis, 10 MET hour increment in transport-related physical activity per week was associated with a reduction in risk for endometrial cancer (RR: 0.91, 95% CI: 0.83-0.997), colorectal cancer (RR: 0.95, 95% CI: 0.91-0.99) and breast cancer (RR: 0.99, 95% CI: 0.89-0.996). The highest level of walking only or walking and cycling combined modes, compared to the lowest level, were significantly associated with a 12% and 30% reduced risk of breast and endometrial cancers respectively. Cycling, compared to motorized modes, was associated with a lower risk of overall cancer incidence and mortality.

CONCLUSION

Active transport appears to reduce cancer risk, but evidence for cancer sites other than colorectum, breast, and endometrium is currently limited.

Temporal changes in cumulative mortality risks of cancer, by occupation, in the working population of Japan from 1995 to 2020: a benchmark for radiation risk comparison

The purpose of this study was to provide benchmark data for discussing the tolerability of cancer risk associated with occupational radiation exposure. It focused on differences in cancer mortality risk by occupation among Japan's working population and examined baseline cancer mortality risks and its variations from 1995 through 2020. Data were collected every five years from national vital statistics sources. By focusing on the same types of cancer among radiation induced effects, cumulative mortality risks were calculated for colorectal, lung, and breast cancer (females only) for those aged 15-74. The average cumulative mortality risk for the working population in Japan has decreased by 30%-60% over the past 25 years. Service workers and male managers were at an average risk, among all workers, while clerical workers and transportation and manufacturing workers had about half the average risk. The risks were higher for professionals and female managers, about 1.5-2 times the average for professionals and up to 5 times the average for female managers. The decrease in the average cancer mortality risk in the working population as a baseline suggests that risk tolerance in society might have changed over time. Since differences in mortality by occupation were confirmed, the usefulness of occupational data as a benchmark needs further investigation, as high-risk/low-risk occupations vary by country and region. The results of this study contribute to put radiation risks into perspective with the background risk of cancer.

Household physical activity and subjective well-being: An international comparison among East Asian older adult populations

PURPOSE

Engaging in lifelong physical activity has multiple health benefits for older populations. Household physical activity occupies older adults' awake time, and they can be an important energy expenditure during the day. The purpose of this study was to investigate the association between older adults' household physical activity and subjective well-being in four East Asian societies.

METHODS

The study design was a secondary data analysis. Data were retrieved from the module of Families 2016 in the database of the East Asian Social Survey. Participants were community-dwelling older adults with a mean age of 70.30±7.50 years and who lived in China, Japan, Korea, and Taiwan. Data were collected by interviews via structured questionnaires between 2016 and 2018. Descriptive analyses, independent t-tests, and an analysis of covariance were performed for the statistical analyses.

RESULTS

In total, there were 3,432 valid responses. Participants who lived in Taiwan had significantly lower levels of total household physical activity than those living in other societies. Older adults' household physical activity was found to significantly differ by age, educational degree, gender, religion, marital status, occupation, and whether living alone. Older adults with high levels of household physical activity had significantly higher self-rated health and marital satisfaction than those with low levels.

CONCLUSIONS

Household physical activity has potential benefits for subjective well-being across international older adult populations. Increasing household physical activity is recommended for older married couples to maintain marital satisfaction.

Dietary Patterns and Lifestyle Factors Associated with the Risk of Colorectal Cancer: A Hospital-Based Case-Control Study among Malaysians

Background

This study aimed to examine the association between dietary patterns, lifestyle factors, and colorectal cancer (CRC) risk among the Malaysian population.

Methods

We recruited 100 patients and 100 controls from two selected government hospitals. Principal component analysis was used to identify dietary patterns using a 123-item semiquantitative food frequency questionnaire. Tobacco smoking and alcohol consumption questionnaires were modified from the WHO STEPS Survey questionnaire. Physical activity levels were assessed using the revised Global Physical Activity questionnaire. Associations between dietary patterns, lifestyle factors and CRC risk were assessed using logistic regression with SPSS version 24.0.

Results

Three dietary patterns were derived from factor analysis: i) vegetables; ii) meat, seafood and processed food; and iii) grains and legumes. High vegetable diet intake was independently and significantly associated with an 81% decreased risk of CRC (odds ratio [OR]: 0.19; 95% confidence interval [CI]: 0.08, 0.46). Both recreational-related physical activity (OR: 2.04; 95% CI: 1.14, 3.64) and vigorous physical activity (OR: 2.06; 95% CI: 1.13, 3.74) are significantly associated with decreased risk of CRC. Increasing the number of cigarettes smoked (≥ 16 cigarettes) per day significantly increased the odds of developing CRC (OR: 2.58; 95% CI: 1.95, 6.75). The duration of alcohol consumption cessation was inversely associated with CRC risk (OR: 2.52; 95% CI: 2.30, 10.57).

Conclusion

The protective effects of a fruit and vegetable diet, and a healthy lifestyle can be used to develop interventions that help reduce the risk of CRC in the Malaysian population.

Causal decomposition maps: An exploratory tool for designing area-level interventions aimed at reducing health disparities

Methods for decomposition analyses have been developed to partition between-group differences into explained and unexplained portions. In this paper, we introduce the concept of causal decomposition maps, which allow researchers to test the effect of area-level interventions on disease maps before implementation. These maps quantify the impact of interventions that aim to reduce differences in health outcomes between groups and illustrate how the disease map might change under different interventions. We adapt a new causal decomposition analysis method for the disease mapping context. Through the specification of a Bayesian hierarchical outcome model, we obtain counterfactual small area estimates of age-adjusted rates and reliable estimates of decomposition quantities. We present two formulations of the outcome model, with the second allowing for spatial interference of the intervention. Our method is utilized to determine whether the addition of gyms in different sets of rural ZIP codes could reduce any of the rural-urban difference in age-adjusted colorectal cancer incidence rates in Iowa ZIP codes.

Factors affecting participation in the colorectal cancer screening program: a cross-sectional population study

PURPOSE

Fecal immunochemical test (FIT) once a year or colonoscopy once in 10 years is the option approved for colorectal cancer (CRC) screening for asymptomatic individuals aged ≥ 50 years in the Czech Republic. We analyzed participation in the screening program to determine possible improvements.

METHODS

In this observational cross-sectional study, data were collected from 4044 randomly chosen individuals from the Czech population (1866 men, 2178 women) aged ≥ 50 years by questionnaires. Individuals who underwent colonoscopy within the last 10 years or/and FIT within the last 2 years were classified as participants in the screening.

RESULTS

1050 individuals underwent FIT, 464 colonoscopy, and 558 underwent both. Adjusted for age, gender, and education, a higher chance of participation in the screening was observed in groups of non-smokers (OR = 1.25; CI 1.05-1.48), ex-smokers (OR = 1.51; CI 1.26-1.83), consuming smoked meat products less than once a week (OR = 1.26; CI 1.09-1.45), practicing physical activity at least once a week (OR = 1.25; CI 1.03-1.51), hospitalized in the past 12 months (OR = 1.73; CI 1.47-2.05), or consulting a general practitioner (GP) in the past 12 months (OR = 2.26; CI 1.87-2.74). The chance of participation of individuals having a risk factor for CRC (obesity, smoking, diabetes, low physical activity, alcohol drinking) was not higher compared to those without the risk factors.

CONCLUSION

Individuals with a tendency to a healthy lifestyle or being in recent contact with the healthcare system by various means, mainly visiting a GP, had a higher participation in the screening for CRC. Among groups with an increased risk for CRC, higher participation was not shown.

What is the optimal type and dose of physical activity for colorectal cancer prevention?

Epidemiological evidence shows that higher levels of physical activity reduce the relative risk of colon cancer by up to 20%. To design optimal physical activity interventions for primary prevention, it is important to understand how the specific characteristics of physical activity (type, intensity, overall volume) influence the magnitude of colon cancer risk reduction. Improving our understanding of the underlying biological mechanisms will also help to manipulate physical activity characteristics to precisely target mechanisms of action and identify populations most likely to benefit. This review synthesizes the best available evidence to explore how the type and dose of physical activity moderate the protective effect of physical activity on colon cancer.

Objectively assessed school-based intervention to reduce children's sedentary time: a systematic review

Childhood is a period characterized by a constant increase in sedentary time (ST) but also provides a great window of opportunity for children to learn how to limit ST. As a result, school-based interventions aimed at reducing and preventing children's ST are increasingly becoming more widespread. A previous review found that school-based multi-component interventions appeared to be more effective in comparison to those based on a single component. However, this conclusion was based on just 11 studies published before 2016 and needs to be verified due to the currently growing number of studies on this topic. The objective of this systematic review is to update the evaluation of the effectiveness of school-based interventions published since the previous review according to the PRISMA guidelines. Studies published between August 2015 and August 2023 containing objective measures of ST were analyzed. Of the 18 studies identified, 11 (61.1%) reported significant positive results. Multi-component studies were slightly more effective than their single-component equivalent (63.7% vs. 57.1%). The components that proved the most effective of the multi-component studies were the implementation of sit-to-stand desks (100%), and teachers' training (77.8%). The combination of these two components is the most promising method to limit ST in the school context. Future research should determine how sit-to-stand desks can be introduced into the class environment and how courses can be adapted to this material.

Cancer risk in information technology workers: a UK Biobank study

BACKGROUND

The information technology (IT) workforce has been growing more rapidly than others, with occupational health (OH) risks of sedentary behaviour, physical inactivity and poor diet, yet studies of their non-communicable disease risk, notably cancer, are lacking.

AIMS

To investigate cancer risk in IT workers compared to others in employment and the nine major Standard Occupational Classification (SOC) groups.

METHODS

We evaluated incident diagnosed cancers in the UK Biobank cohort through national cancer registry linkage. Cox proportional hazard regression models, with 15-year follow-up, were used to compare incident cancer risk among IT workers with all other employed participants and with the nine major SOC groups.

RESULTS

Overall, 10 517 (4%) employed participants were IT workers. Adjusting for confounders, IT workers had a slightly lower cancer incidence compared to all other employed participants (Model 2: hazard ratio = 0.91, 95% confidence interval [CI] 0.83-1.01). Compared to the nine major SOC groups, they had a similar (Major Groups 2, 5 and 8) or lower (Major Groups 1, 3, 4, 6, 7 and 9) cancer incidence.

CONCLUSIONS

Despite their occupational risks of sedentary behaviour, poor diet and physical inactivity, IT workers do not have an increased cancer incidence compared to all other employed participants and the nine major SOC groups. This study paves the way for large, longitudinal health outcome studies of this under-researched and rapidly growing occupational group.

Physical activity, polygenic risk score, and colorectal cancer risk

INTRODUCTION

Whether and to what extent the relationship between physical activity (PA) and colorectal cancer (CRC) differs according to CRC-related genetic risk remains to be determined, and no studies to date have quantified how much genetically determined risk could be compensated for with active exercise.

METHODS

Genetic risk was quantified by a polygenic risk score (PRS) summarizing the estimated effect of 140 CRC-associated genetic variants. Associations of PA with CRC risk were estimated by multivariable logistic regression across PRS levels. We also compared the impact of PA and specific PA types to the PRS using "genetic risk equivalent (GRE)", a novel approach to enhance effective risk communication.

RESULTS

Among 5058 CRC patients and 4134 controls, we observed no significant association between overall PA level in quartiles and CRC risk. However, the highest versus lowest lifetime leisure time physical activity (LTPA) was associated with a 13% lower CRC risk [odds ratio 0.87, 95% confidence interval (CI) 0.77-1.00] independent of PRS levels (adjusted p value for interaction = 0.18). This effect was equivalent to the effect of having 11 percentiles lower PRS (GRE -10.6, 95% CI -20.7 to -0.6). The GRE (95% CI) for the highest lifetime sports tertile was -23.0 (-33.9 to -12.0).

CONCLUSIONS

LTPA was inversely associated with CRC risk irrespective of polygenic risk for CRC, which reinforces the importance of LTPA in CRC prevention among the general population. Adequate sports activity can compensate for a large share of polygenic risk for CRC.

Beyond colonoscopy: Physical activity as a viable adjunct to prevent colorectal cancer

Colorectal cancer (CRC) is a common cancer with an increasing incidence worldwide. The implementation of a mass screening program has been proven effective in reducing the global burden of CRC, but its effectiveness is not ideal and some metabolic derangements and lifestyle factors were reported to be attributable for such a deficit. Implementing positive lifestyle intervention as primary prevention therefore becomes critical because colorectal carcinogenesis can be promoted by several lifestyle factors, such as a lack of physical activity. Herein, we review the current evidence on the association and possible mechanisms between physical activity and CRC carcinogenesis. In addition, since CRC prevention heavily relies on resection of precancerous polyps and subsequent surveillance by colonoscopy, this review will also explore the impact of physical activity on populations with different colorectal polyp risks and its potential adjunct role in altering surveillance outcomes.

Geographical variations of cancer incidence in Guadeloupe, French West Indies

Background

Geographical disparities in cancer incidence are observed at different scales and may highlight areas of high risk that need special attention to improve health policies. In Guadeloupe, a French archipelago in the Caribbean, environmental and socioeconomic factors are potential factors associated with cancer incidence. Our objective was to describe geographical variations of cancer incidence in Guadeloupe at a small-area level, in order to identify potential clusters.

Methods

We conducted spatial analyses for the 18 most frequent cancer sites, using data collected by the population-based cancer registry of Guadeloupe over the period 2008–2017. For each cancer sites, we used the Besag, York and Mollié model to estimate smoothed standardized incidence ratios (SIRs) at a sub-municipality level. In addition, we performed ascendant hierarchical clustering of these smoothed SIRs to describe the relationship between the different cancer sites and to identify geographical clusters.

Results

We observed geographical disparities with a spatial pattern that varied across cancer sites. Clustering of the smoothed SIRs showed aggregations between breast cancer and multiple myeloma, thyroid and stomach cancer, cervical and head and neck cancers, lung and rectal cancers, ovarian and endometrial cancers. Cluster analysis also identified six geographical clusters. Features of these clusters suggest alcohol consumption, exposure to pesticides, pollution generated by open landfills, and ethnicity as possible explanatory factors.

Discussion/conclusion

Our study provided for the first time an extensive description of geographical disparities in cancer incidence in Guadeloupe, in a region where socioeconomic and environmental issues are major concerns. Although the identification of underlying factors was out of the scope of the present study, we highlighted areas of special interest and put forward some hypotheses that warrant to be further investigated in more in-depth analyses.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09886-6.

Sedentary behavior and cancer-an umbrella review and meta-analysis

Several systematic reviews and meta-analyses have summarized the association between sedentary behavior (SB) and cancer. However, the level of evidence and the potential for risk of bias remains unclear. This umbrella review summarized the current data on SB in relation to cancer incidence and mortality, with a particular emphasis on assessing the risk of bias. We searched PubMed, Web of Science and Cochrane Database for systematic reviews and meta-analyses on the association between SB and cancer incidence and mortality. We also searched for recent observational studies not yet included in existing meta-analyses. We re-calculated summary risk estimates for cancer incidence and mortality using random effects models. We included 14 meta-analyses covering 17 different cancer sites from 77 original studies. We found that high SB levels increase the risk for developing ovarian, endometrial, colon, breast, prostate, and rectal cancers, with relative risks of 1.29 (95% confidence interval (CI) = 1.08-1.56), 1.29 (95% CI = 1.16-1.45), 1.25 (95% CI = 1.16-1.33), 1.08 (95% CI = 1.04-1.11), 1.08 (95% CI = 1.00-1.17), and 1.07 (95% CI = 1.01-1.12), respectively. Also, we found an increased risk of cancer mortality of 1.18 (95% CI = 1.09-1.26). Most associations between SB and specific cancer sites were supported by a "suggestive" level of evidence. High levels of SB are associated with increased risk of several types of cancer and increased cancer mortality risk.

Association of Physical Activity and Sedentary Behavior With the Risk of Colorectal Cancer

BACKGROUND

Although recent evidence supports that prolonged sedentary behavior and reduced physical activity are associated with colorectal cancer risk, there are few studies analyzing the colorectal cancer risk according to different types of physical activity and combined effects of sedentary behavior and physical activity on colorectal cancer. This study aimed to investigate the association of sedentary behavior and physical activity with colorectal cancer.

METHODS

A cross-sectional study included a total of 33,403 participants from the Korea National Health and Nutrition Examination Survey from 2014 to 2019. Sedentary behavior was dichotomized into < 10 hr/day and ≥ 10 hr/day, and three types of physical activity were investigated, including leisure-time, occupational, and transportation physical activity. Multiple logistic regression analyses were performed to assess the risk of colorectal cancer in relation to sedentary behavior and physical activity.

RESULTS

Sedentary behavior was associated with an increased risk of colorectal cancer (odds ratio [OR] 1.64; 95% confidence interval [CI], 1.22-2.21), while the different domains of physical activity were not significantly associated with colorectal cancer risk. In a combined analysis, those with sedentary behavior and without physical activity showed an increased risk of colorectal cancer compared to that of the reference category without sedentary behavior and with physical activity (OR, 1.49; 95% CI, 1.02-2.16).

CONCLUSION

This study found that sedentary behavior was significantly associated with the increased risk of colorectal cancer. Moreover, sedentary behavior without physical activity increased the risk of colorectal cancer. Reducing sedentary behavior and recommending any type of physical activity may reduce the risk of colorectal cancer.

Pairwise association of key lifestyle factors and risk of colorectal cancer: a prospective pooled multicohort study

BACKGROUND

Several lifestyle factors are associated with an increased risk of colorectal cancer (CRC). Although lifestyle factors co-occur, in most previous studies these factors have been studied focusing upon a single risk factor or assuming independent effects between risk factors.

AIM

To examine the pairwise effects and interactions of smoking, alcohol consumption, physical inactivity, and body mass index (BMI) with risk of subsequent colorectal cancer (CRC).

METHODS AND RESULTS

We used METCA cohort data (pooled data from seven population-based Finnish health behavior survey studies during years 1972-2015) consisting of 171 063 women and men. Participants' smoking, alcohol consumption, physical inactivity and BMI measures were gathered, and participants were categorized into those exposed and those not exposed. The incidence of CRC was modeled by Poisson regression with main and interaction effects of key lifestyle factors. The cohort members were followed-up through register linkage to the Finnish Cancer Registry for first primary CRC case until the end of 2015. Follow-up time was 1715, 690 person years. The highest pairwise CRC risk was among male smokers who had overweight (BMI ≥ 25 kg/m² ) (HR 1.75, 95% CI 1.36-2.26) and women who had overweight and consumed alcohol (HR 1.45, 95% CI 1.14-1.85). Overall, among men the association of lifestyle factors and CRC risk was stronger than among women. In men, both having overweight and being a smoker combined with any other adverse lifestyle factor increased CRC risk. Among women, elevated CRC risks were observed for those who were physically inactive and who consumed alcohol or had overweight. No statistically significant interactions were detected between pairs of lifestyle factors.

CONCLUSIONS

This study strengthens the evidence of overweight, smoking, and alcohol consumption as CRC risk factors. Substantial protective benefits in CRC risk can be achieved by preventing smoking, maintaining BMI to <25 kg/m² and not consuming alcohol.

Perceptions of physical activity and sedentary behaviour guidelines among end-users and stakeholders: a systematic review

Background

Many of the world’s population, across all age groups and abilities, are not meeting or even aware of internationally recommended physical activity (PA) and sedentary behaviour (SB) guidelines. In order to enhance awareness and uptake, guidelines should be perceived positively by targeted users. The purpose of this study was to review the literature on end-user and stakeholder perceptions of PA and SB guidelines.

Methods

The electronic databases APA PsycInfo, CINAHL, MEDLINE, and SPORTDiscus, using EBSCOhost Research Platform, and Web of Science were searched from inception to June, 2021 with keyword synonyms for “perceptions”, “PA guidelines”, and “SB guidelines”. Studies of any design that collected stakeholder and/or end-user responses to a PA and/or SB guideline were included and assessed for risk of bias. The PA and/or SB guideline could be any type of official form (e.g., national documents, organizational guidelines, expert consensus statements, etc.) from any country, that targets individuals at the regional, provincial/statewide, national, or international level, and includes all types of guidelines (e.g., strength, aerobic, clinical, nonclinical, screen-time, sitting, etc.). Data were extracted and analyzed using thematic synthesis.

Results

After screening 1399 abstracts and applying citation screening, 304 full-texts were retrieved. A total of 31 articles met the inclusion criteria. End-users and stakeholders for PA guidelines across all age groups expressed the need for simplified language with more definitions, relatable examples and imagery, and quantification of PA behaviours. There was concern for the early years and child PA guidelines leading to guilt amongst parents and the SB guidelines, particularly the recommendations to limit screen-time, being unrealistic. General age group PA guidelines were not perceived as usable to populations with differing abilities, clinical conditions, and socioeconomic status. Guidelines that targeted clinical populations, such as persons with multiple sclerosis and persons with spinal cord injury, were well received.

Conclusions

There is a clear need to balance the evidence base with the pragmatic needs of translation and uptake so that the guidelines are not ignored or act as a barrier to actual engagement.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12966-022-01245-9.

Dietary Risk Factors and Odds of Colorectal Adenoma in Malaysia: A Case Control Study

Current evidence suggests that dietary and lifestyle factors may play an important role in colorectal cancer risk but there are only a few studies that investigated their relationship with colorectal adenomas (CRA), the precursors for colorectal cancer. A case-control study was conducted to determine the relationship between dietary and lifestyle factors associated with CRA risk among 125 subjects with CRA and 150 subjects without CRA at Hospital Canselor Tuanku Muhriz UKM (HCTM), Malaysia. We used dietary history questionnaire (DHQ) and International Physical Activity Questionnaire-Short Form (IPAQ) to estimate the diet and physical activity. The findings of this study showed that male gender [OR = 2.71 (95% CI= 1.01-7.27)], smoking [OR = 6.39 (95% CI= 1.04-39.30)], family history of cancer [OR = 6.39 (95% CI= 1.04-39.30)], high body fat percentage [OR = 1.25 (95% CI= 1.04-1.51)], high calorie and fat intake [OR = 1.03 (95% CI= 1.01-1.06)], [OR = 1.01 (95% CI= 0.95-1.09)] and red meat intake more than 100 g per day [OR = 1.02 (95% CI= 1.01-1.04)] increased CRA risk. High fiber [OR = 0.78 (95% CI= 0.64-0.95)] and calcium intake [OR = 0.78 (95% CI= 0.98-1.00)] was found to decrease CRA risk. Some of these modifiable risk factors could be advocated as lifestyle interventions to reduce risk of CRA.

Predictors of CRC Stage at Diagnosis among Male and Female Adults Participating in a Prospective Cohort Study: Findings from Alberta's Tomorrow Project

Colorectal cancer (CRC) is a leading cause of morbidity and mortality in Canada. CRC screening and other factors associated with early-stage disease can improve CRC treatment efficacy and survival. This study examined factors associated with CRC stage at diagnosis among male and female adults using data from a large prospective cohort study in Alberta, Canada. Baseline data were obtained from healthy adults aged 35–69 years participating in Alberta’s Tomorrow Project. Factors associated with CRC stage at diagnosis were evaluated using Partial Proportional Odds models. Analyses were stratified to examine sex-specific associations. A total of 267 participants (128 males and 139 females) developed CRC over the study period. Among participants, 43.0% of males and 43.2% of females were diagnosed with late-stage CRC. Social support, having children, and caffeine intake were predictors of CRC stage at diagnosis among males, while family history of CRC, pregnancy, hysterectomy, menopausal hormone therapy, lifetime number of Pap tests, and household physical activity were predictive of CRC stage at diagnosis among females. These findings highlight the importance of sex differences in susceptibility to advanced CRC diagnosis and can help inform targets for cancer prevention programs to effectively reduce advanced CRC and thus improve survival.

Research Relating to Low Back Pain and Physical Activity Reported Over the Period of 2000-2020

BACKGROUND

Low back pain (LBP) is a highly prevalent musculoskeletal disorder that contributes to the greatest degree of disability worldwide. It has become a very serious public health problem that has attracted considerable research interest. The number of publications associated with LBP and physical activity (PA) is gradually increasing. Nevertheless, few studies have utilised visualisation in analysing the general aspects of this field. Therefore, we aimed to provide a systematic overview of global scientific research related to low back pain and physical activity from 2000 to 2020. It has significant benefits in terms of providing researchers with the status and trends of research on low back pain and physical activity.

METHODS

Publications on Science Citation Index-Expanded of Web of Science from 2000 to 2020 were searched, and publications relevant to LBP and PA were analysed using Citespace and SPSS. Analyses mainly included cooperation amongst authors, countries and institutions; co-occurrence analysis of keywords; and co-citation analysis of references, revealing productive researchers and contributing institutions tracking the status and trend of research fields.

RESULTS

Results of linear regression analysis showed that the number of publications on LBP and PA studies increased significantly (p<0.001). The subject categories predominantly focused on orthopaedics (2579, 26.54%), rehabilitation (2544, 26.18%) and sport sciences (2015, 25.44%). The United States had the highest number of published papers (2700, 27.789%) and citations (86, 958). In terms of the number of publications, amongst the top 20 journals, Spine contributed the most, whilst the British Journal of Sports Medicine had the highest impact factor (IF2019, 12.022). The University of Sydney had the highest number of publications (330 publications). Maher published the most papers (123 papers) and had the highest H-index (41). Several citation articles and keywords (such as aerobic, obesity and fear-avoidance beliefs) can be used to provide frontier clues for research on LBP and PA.

CONCLUSION

The results of our study may provide information, such as research trends and frontiers of research and collaborating partners, institutions and countries, on LBP and PA.

Active commuting and leisure-time physical activity among adults in western Nepal: a cross-sectional study

OBJECTIVE

To determine the prevalence and sociodemographic factors associated with active commuting and leisure-time physical activity (LTPA) among adults in western Nepal.

DESIGN

Cross-sectional study.

SETTING

Adults from semiurban areas in western Nepal.

PARTICIPANTS

2815 adults aged 25-65 years who participated in the 'Community-Based Management of Hypertension in Nepal (COBIN)' Study. Multiple logistic regression analysis was used to identify the sociodemographic factors associated with active commuting and LTPA.

OUTCOME

Self-reported participation in active commuting and LTPA.

RESULTS

Most study participants (96%) commuted actively (walked or cycled) from one place to another. Our results showed that only a small proportion (3.7%) of participants engaged in moderate or vigorous LTPA. Compared with those in paid employment, the odds of commuting actively were higher among people working in agriculture or as labourers (OR: 4.57, 95% CI: 2.46 to 8.48), those retired/unemployed (OR: 2.98, 95% CI: 1.42 to 6.25) and those in unpaid employment (OR: 1.85, 95% CI: 1.06 to 3.22). Adults who were overweight or had obesity were less likely to commute actively. Compared with adults aged 25-34 years, older adults were less likely (OR: 0.35, 95% CI: 0.17 to 0.72) to engage in LTPA. Women were 0.46 times less likely to engage in LTPA compared with men.

CONCLUSION

Most adults engaged in active commuting for work or travel. Less than 5% participated in any form of moderate or vigorous LTPA. Longitudinal studies incorporating objective assessment of physical activity and a range of individual, interpersonal, and environmental factors will help understand how to promote active commuting and LTPA among Nepalese adults.Trial registration number: ClinicalTrials.gov NCT02428075.

Socio-ecological influences of leisure-time physical activity among Nepalese adults: a qualitative study

Background

With economic and social changes, participation in occupational and transport-related physical activity is declining among Nepalese adults, highlighting the growing importance of leisure-time physical activity. However, limited information is available to guide public health policies and interventions to promote leisure-time physical activity in Nepal. This study aimed to qualitatively explore the socioecological influences of participation in leisure-time physical activity among Nepalese adults aged 40 years and above.

Methods

A total of 51 adults (30 females and 21 males) participated in one of the nine focus groups conducted in Kathmandu, Nepal. A semi-structured guide based on the social-ecological model of physical activity was used to facilitate these focus groups. Data were analysed using a reflexive thematic analysis approach in NVivo 12.

Results

Participation in leisure-time physical activity was minimal and leisure time was mostly spent resting, socialising, or engaging in sedentary activities such as watching television. Walking was the most common form of leisure-time physical activity, and men reported being more active than women. Individual-level barriers included lack of knowledge, lack of skill, lack of motivation, considering oneself as sufficiently active and engagement in sedentary screen activities. Family and household responsibilities, lack of support and fear of being judged constituted the interpersonal barriers while environmental barriers included an absence of a supportive social norm, lack of open spaces, weather conditions and perceived lack of safety. Health benefits, prioritising physical activity, social support, provision of group-based activities and age-appropriate public exercise facilities were identified as major facilitators.

Conclusion

Critical issues that need to be addressed to increase leisure-time physical activity among Nepalese adults include traditional gender roles, family and social support, and social norms. Modifications of the built environment, such as public exercise facilities, offer further opportunities and will require coordination beyond the health sector.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-021-11484-3.

Sedentary behaviour associations with health outcomes in people with severe mental illness: a systematic review

BACKGROUND

Although people with severe mental illness (SMI) show high sedentary behaviour (SB) levels, there is little research on how SB patterns influence health and which type of intervention is the most critical for reducing this behaviour. The aims of this study are to examine associations between SB and physical and mental health in people with SMI; and the extent to which physical activity interventions may effectively reduce SB.

METHODS

This systematic review was conducted according to the PRISMA guidelines. Experimental and observational studies were searched in Medline, PsycInfo, Embase, CINHAL and Scopus up to June 2018. Eighteen studies (n = 15 observational; n = 3 experimental) met the inclusion criteria.

RESULTS

Both subjective and objective measurements for SB (an average of 8.5 and 10 h day-1, respectively) were positively associated with an increased cardiovascular and metabolic risk, worse global functioning, less quality of life, more severity of depressive symptoms, longer illness duration and higher doses of antipsychotic medication. Regarding intervention studies, active-lifestyle interventions (n = 2) reduced sedentary time (1.7-2.4 h day-1) while structured exercise (n = 1) reported no changes on SB.

CONCLUSIONS

Levels of sedentariness in people with SMI are linked to an increased physical health risk, worse wellbeing and poorer mental health. Active-lifestyle interventions may be an indicated approach to reduce SB of people with SMI. However, a limited number of studies, their mixed quality and the heterogeneity of health outcomes made it difficult to provide robust conclusions on SB effects in people with SMI.Study protocol was registered to PROSPERO (CRD42017067592).

Physical activity and mortality in patients with colorectal cancer: a meta-analysis of prospective cohort studies

The association between physical activity (PA) and colorectal cancer (CRC) patients' survival is inconsistent. We conducted a systematic review and meta-analysis to summarize published articles on this issue. We performed a comprehensive search of the PubMed, Embase, and Web of Science databases for relevant articles through 28 February 2018. The summary hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using a random-effects model. Eighteen prospective cohort studies were included in the meta-analysis, with a total of 9257 cases of total mortality (TM) and 4015 cases of colorectal cancer-specific mortality (CRCSM) among 31 873 CRC survivors and 557 150 general populations. Among CRC survivors, the highest versus the lowest levels of prediagnosis PA showed decreased risks of TM (summary HR = 0.81, 95% CI: 0.76-0.87, I = 1.8%) and CRCSM (summary HR = 0.85, 95% CI: 0.77-0.98, I = 0), respectively. Significant risk reductions for TM and CRCSM were also demonstrated for postdiagnosis PA (HR = 0.63, 95% CI: 0.54-0.74; and HR = 0.64, 95% CI: 0.47-0.88, respectively). The inverse association between prediagnosis PA and cancer mortality was more pronounced for colon cancer than that for rectal cancer (P = 0.08). The summary HRs (95% CIs) of TM were 0.89 (0.83-0.97) and 0.79 (0.69-0.90) per 10 metabolic equivalent task-h/week increase in prediagnosis and postdiagnosis PA, respectively. Our meta-analysis provides comprehensive evidence that PA performed before or after cancer diagnosis is related to reduced mortality risk among CRC survivors.

Risk factors for early-onset colorectal cancer: a population-based case-control study in Ontario, Canada

Purpose

There has been an alarming increase in colorectal cancer (CRC) incidence among young adults aged < 50 years, and factors driving this upward trend are unknown. This study investigated associations between various medical, lifestyle, and dietary factors and risk of early-onset CRC (EO-CRC).

Methods

A population-based case–control study was conducted in Ontario, Canada during 2018–2019. EO-CRC cases aged 20–49 years (n = 175) were identified from the Ontario Cancer Registry; sex- and age group-matched controls (n = 253) were recruited through random digit dialing. Data on potential a priori risk factors were collected using a web-based self-reported questionnaire. Odds ratios (OR) and 95% confidence intervals (CI) were estimated using multivariable logistic regression.

Results

Family history of CRC in a first- or second-degree relative (OR 2.37; 95% CI 1.47–3.84), longer sedentary time (≥ 10 vs. < 5 h/day, OR 1.93; 95% CI 1.02–3.65), greater consumption of sugary drinks (≥ 7 vs. < 1 drinks/week, OR 2.99; 95% CI 1.57–5.68), and a more Westernized dietary pattern (quartile 4 vs. 1, OR 1.92; 95% CI 1.01–3.66) were each associated with an increased risk of EO-CRC. Conversely, calcium supplement use (OR 0.53; 95% CI 0.31–0.92), history of allergy or asthma (OR 0.62; 95% CI 0.39–0.98), and greater parity in females (≥ 3 vs. nulliparity, OR 0.29; 95% CI 0.11–0.76) were each associated with a reduced risk.

Conclusion

Modifiable factors, particularly sedentary behavior and unhealthy diet including sugary drink consumption, may be associated with EO-CRC risk. Our findings, if replicated, may help inform prevention strategies targeted at younger persons.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10552-021-01456-8.

Leisure-time, occupational, and commuting physical activity and the risk of chronic kidney disease in a working population

Physical activity has been linked to a lower risk of chronic kidney disease (CKD); however, evidence on the relationship between domain-specific physical activity and CKD is scarce. This study aimed to examine the risk of CKD in relation to leisure-time, occupational, and commuting physical activities in a large occupational cohort in Japan. Participants were 17,331 workers (20-65 years old) without CKD and were followed-up for a maximum period of 13 years. Incident CKD was defined as an estimated glomerular filtration rate of < 60 mL/min/1.73 m² and/or proteinuria determined using the dipstick test. The Cox proportional hazards models were used to examine the associations. During 147,752 person-years of follow-up, 4013 participants developed CKD. Workers who were standing or walking at work and those who were fairly active at work had adjusted hazard ratios of 0.88 (95% confidence interval 0.86-0.96) and 0.89 (95% confidence interval 0.78-1.02), respectively, for developing CKD than sedentary workers. Leisure-time physical activity and walking for commute were not associated with CKD risk. Our findings suggest that occupational, but not leisure-time and commuting physical activities, is associated with a lower CKD risk.

A Physically Active Status Affects the Circulating Profile of Cancer-Associated miRNAs

Circulating miRNAs are ideal diagnostics and prognostics biomarkers in cancer since altered levels of specific miRNAs have been associated to development/progression of several cancers. Physical activity is a recognized preventive strategy against several cancers, but it may also modify the baseline levels of cancer-associated miRNAs and, hence, may act as a confounding pre-analytical variable. This study aimed at understanding whether physical activity-dependent changes in cancer-associated circulating miRNAs profile could act as a confounding variable. A panel comprising 179 miRNAs was assayed in plasma from 20 highly trained and 10 sedentary men. RT-qPCR data were analyzed with the 2^−2ΔΔCT methods and normalized on hsa-miR-320d, as determined by bioinformatics analysis. miRNAs associated with the diagnosis of the most prevalent cancers were considered. Only those miRNAs, relevantly associated with cancers, found ≥2-fold up- or downregulated in highly trained subjects compared to sedentary were disclosed. The results reveal that chronic physical activity determined modifications altering the baseline level of several cancer-associated miRNAs and, hence, their diagnostic and prognostic potential. In conclusion, based on our results, a physically active status emerges as an important pre-analytical variable able to alter the basal level of circulating miRNAs, and these alterations might be considered as potentially misleading the analytical output.

Association of sedentary work with colon and rectal cancer: systematic review and meta-analysis

OBJECTIVES

There has been no research on sedentary behaviour in the occupational domain that occupies a large portion of the daily life.

METHODS

We conducted a meta-analysis to investigate the association between sedentary work and colorectal cancer. We searched PubMed, Embase and Cochrane databases up to 12 August 2020 for peer-reviewed journal articles that assessed the association between sedentary work and colon or rectal cancer. Pooled estimates of ORs were obtained using random effects models. Statistical tests for publication bias, heterogeneity and sensitivity analysis were applied.

RESULTS

Of the 5 381 studies initially identified, 23 studies with 64 reports were eligible for inclusion. Sedentary work significantly increased the risk of colon cancer (pooled OR=1.21, 95% CI 1.11 to 1.31, p value ≤0.0001) and rectal cancer (pooled OR=1.08, 95% CI 1.00 to 1.16, p value=0.0395). The adjustment for leisure time physical activity attenuated the association and made the risk estimates non-significant for sedentary behaviour, but the association was independent of sex, control of body mass index and assessment of sedentary behaviour.

CONCLUSIONS

We found evidence of association between sedentary work and the risk of colon or rectal cancer. Limiting excessive sedentary work could be an important means of preventing colon and rectal cancer.

How does occupational physical activity influence health? An umbrella review of 23 health outcomes across 158 observational studies

OBJECTIVE

Physical activity (PA) has substantial benefits across a range of health outcomes. There is uncertainty about the PA-specific health effects, and in particular, the occupational domain. In this umbrella review, we synthesised available evidence on the associations between occupational PA (OPA) and health-related outcomes (including cancer, all-cause mortality and cardiovascular disease). This work informed the development of WHO's guidelines on PA and sedentary behaviour (2020).

DESIGN

Umbrella review of systematic reviews.

DATA SOURCE

We performed a literature search in PubMed, Web of Science, Embase, CINAHL and Sportdiscuss from database inception to 2 December 2019.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

We included systematic reviews if they contained a quantitative assessment of OPA and its relationship with at least one health-related outcome.

RESULTS

We summarised the evidence of 17 reviews covering 23 unique health-related outcomes. We graded most evidence as low or very low, or moderate quality. We found health benefits for those engaging in high versus low OPA for multiple cancer outcomes (including colon and prostate), ischaemic stroke, coronary heart disease and mental health (ie, mental well-being and life satisfaction). High OPA was associated with unfavourable health outcomes for all-cause mortality in men, mental ill health (ie, depression and anxiety), osteoarthritis, and sleep quality and duration.

CONCLUSIONS

We found favourable associations for most health-related outcomes with high OPA levels, but we also found some evidence for unfavourable associations due to high OPA levels. At this point, there is a need for better quality evidence to provide a unequivocal statement on the health effects of OPA.

Genetically predicted physical activity levels are associated with lower colorectal cancer risk: a Mendelian randomisation study

BACKGROUND

We conducted a Mendelian randomisation (MR) study to investigate whether physical activity (PA) causes a reduction of colorectal cancer risk and to understand the contributions of effects mediated through changes in body fat.

METHODS

Common genetic variants associated with self-reported moderate-to-vigorous PA (MVPA), acceleration vector magnitude PA (AMPA) and sedentary time were used as instrumental variables. To control for confounding effects of obesity, we included instrumental variables for body mass index (BMI), body fat percentage, waist circumference and arm, trunk and leg fat ratios. We analysed the effect of these instrumental variables in a colorectal cancer genome-wide association study comprising 31,197 cases and 61,770 controls of European ancestry by applying two-sample and multivariable MR study designs.

RESULTS

We found decreased colorectal cancer risk for genetically represented measures of MVPA and AMPA that were additional to effects mediated through genetic measures of obesity. Odds ratio and 95% confidence interval (CI) per standard deviation increase in MVPA and AMPA was 0.56 (0.31, 1.01) and 0.60 (0.41, 0.88), respectively. No association has been found between sedentary time and colorectal cancer risk. The proportion of effect mediated through BMI was 2% (95% CI: 0, 14) and 32% (95% CI: 12, 46) for MVPA and AMPA, respectively.

CONCLUSION

These findings provide strong evidence to reinforce public health measures on preventing colorectal cancer that promote PA at a population level regardless of body fatness.

Colorectal Cancer Risk Following Bariatric Surgery in a Nationwide Study of French Individuals With Obesity

Importance

Although bariatric surgery is effective against morbid obesity, the association of this surgery with the risk of colorectal cancer remains controversial.

Objective

To assess whether bariatric surgery is associated with altered risk of colorectal cancer among individuals with obesity.

Design, Setting, and Participants

This retrospective, population-based, multicenter, cohort study based on French electronic health data included 1 045 348 individuals with obesity, aged 50 to 75 years, and free of colorectal cancer at baseline. All inpatients with obesity having data recorded during a hospital stay between 2009 and 2018 by the French national health insurance information system database were followed up for a mean (SD) of 5.3 (2.1) years for those who did not undergo bariatric surgery and 5.7 (2.2) years for those who underwent bariatric surgery. Two groups of patients comparable in terms of age, sex, body mass index, follow-up, comorbidities, and conditions who did or did not undergo surgery were also obtained by propensity score matching.

Exposures

Bariatric surgery (n = 74 131), including adjustable gastric banding, sleeve gastrectomy, gastric bypass; or no bariatric surgery (n = 971 217).

Main Outcomes and Measures

Primary outcome was incident colorectal cancer. Standardized incidence ratios were calculated using age-, sex-, and calendar year-matched colorectal cancer incidence among the general French population during the corresponding years. Secondary outcome was incident colorectal benign polyps.

Results

Among a total of 1 045 348 patients, the mean (SD) age was 57.3 (5.5) years for the 74 131 patients in the surgical cohort vs 63.4 (7.0) years for the 971 217 patients in the nonsurgical cohort. The mean (SD) follow-up was 6.2 (2.1) years for patients who underwent adjustable gastric banding, 5.5 (2.1) years for patients who underwent sleeve gastrectomy, and 5.7 (2.2) years for patients who underwent gastric bypass. In total, 13 052 incident colorectal cancers (1.2%) and 63 649 colorectal benign polyps were diagnosed. The rate of colorectal cancer was 0.6% in the bariatric surgery cohort and 1.3% in the cohort without bariatric surgery. In the latter cohort, 9417 cases were expected vs 12 629 observed, a standardized incidence ratio of 1.34 (95% CI, 1.32-1.36). In the bariatric surgery cohort, 428 cases were expected and 423 observed, a standardized incidence ratio of 1.0 (95% CI, 0.90-1.09). Propensity score-matched hazard ratios in comparable operated vs nonoperated groups were 0.68 (95% CI, 0.60-0.77) for colorectal cancer and 0.56 (95% CI, 0.53-0.59) for colorectal benign polyp. There were fewer new diagnoses of colorectal cancer after gastric bypass (123 of 22 343 [0.5%]) and sleeve gastrectomy (185 of 35 328 [0.5%]) than after adjustable gastric banding (115 of 16 460 [0.7%]), and more colorectal benign polyps after adjustable gastric banding (775 of 15 647 [5.0%]) than after gastric bypass (639 of 20 863 [3.1%]) or sleeve gastrectomy (1005 of 32 680 [3.1%]).

Conclusion and Relevance

The results of this nationwide cohort study suggested that following bariatric surgery, patients with obesity share the same risk of colorectal cancer as the general population, whereas for patients with obesity who do not undergo bariatric surgery, the risk is 34% above that of the general population.

Association between physical activity and digestive-system cancer: An updated systematic review and meta-analysis

BACKGROUND

Physical activity (PA) may have an impact on digestive-system cancer (DSC) by improving insulin sensitivity and anticancer immune function and by reducing the exposure of the digestive tract to carcinogens by stimulating gastrointestinal motility, thus reducing transit time. The current study aimed to determine the effect of PA on different types of DSC via a systematic review and meta-analysis.

METHODS

In accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, we searched for relevant studies in PubMed, Embase, Web of Science, Cochrane Library, and China National Knowledge Infrastructure. Using a random effects model, the relationship between PA and different types of DSC was analyzed.

RESULTS

The data used for meta-analysis were derived from 161 risk estimates in 47 studies involving 5,797,768 participants and 55,162 cases. We assessed the pooled associations between high vs. low PA levels and the risk of DSC (risk ratio (RR)  = 0.82, 95% confidence interval (95%CI): 0.79-0.85), colon cancer (RR = 0.81, 95%CI: 0.76-0.87), rectal cancer (RR = 0.88, 95%CI: 0.80-0.98), colorectal cancer (RR = 0.77, 95%CI: 0.69-0.85), gallbladder cancer (RR = 0.79, 95%CI: 0.64-0.98), gastric cancer (RR = 0.83, 95%CI: 0.76-0.91), liver cancer (RR = 0.73, 0.60-0.89), oropharyngeal cancer (RR = 0.79, 95%CI: 0.72-0.87), and pancreatic cancer (RR = 0.85, 95%CI: 0.78-0.93). The findings were comparable between case-control studies (RR = 0.73, 95%CI: 0.68-0.78) and prospective cohort studies (RR = 0.88, 95%CI: 0.80-0.91). The meta-analysis of 9 studies reporting low, moderate, and high PA levels, with 17 risk estimates, showed that compared to low PA, moderate PA may also reduce the risk of DSC (RR = 0.89, 95%CI: 0.80-1.00), while compared to moderate PA, high PA seemed to slightly increase the risk of DSC, although the results were not statistically significant (RR = 1.11, 95%CI: 0.94-1.32). In addition, limited evidence from 5 studies suggested that meeting the international PA guidelines might not significantly reduce the risk of DSC (RR = 0.96, 95%CI: 0.91-1.02).

CONCLUSION

Compared to previous research, this systematic review has provided more comprehensive information about the inverse relationship between PA and DSC risk. The updated evidence from the current meta-analysis indicates that a moderate-to-high PA level is a common protective factor that can significantly lower the overall risk of DSC. However, the reduction rate for specific cancers may vary. In addition, limited evidence suggests that meeting the international PA guidelines might not significantly reduce the risk of DSC. Thus, future studies must be conducted to determine the optimal dosage, frequency, intensity, and duration of PA required to reduce DSC risk effectively.

New global guidelines on sedentary behaviour and health for adults: broadening the behavioural targets

BACKGROUND

In 2018, the World Health Organisation (WHO) commenced a program of work to update the 2010 Global Recommendations on Physical Activity for Health, for the first-time providing population-based guidelines on sedentary behaviour. This paper briefly summarizes and highlights the scientific evidence behind the new sedentary behaviour guidelines for all adults and discusses its strengths and limitations, including evidence gaps/research needs and potential implications for public health practice.

METHODS

An overview of the scope and methods used to update the evidence is provided, along with quality assessment and grading methods for the eligible new systematic reviews. The literature search update was conducted for WHO by an external team and reviewers used the AMSTAR 2 (Assessment of Multiple Systematic Reviews) tool for critical appraisal of the systematic reviews under consideration for inclusion. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) method was used to rate the certainty (i.e. very low to high) of the evidence.

RESULTS

The updated systematic review identified 22 new reviews published from 2017 up to August 2019, 14 of which were incorporated into the final evidence profiles. Overall, there was moderate certainty evidence that higher amounts of sedentary behaviour increase the risk for all-cause, cardiovascular disease (CVD) and cancer mortality, as well as incidence of CVD, cancer, and type 2 diabetes. However, evidence was deemed insufficient at present to set quantified (time-based) recommendations for sedentary time. Moderate certainty evidence also showed that associations between sedentary behaviour and all-cause, CVD and cancer mortality vary by level of moderate-to-vigorous physical activity (MVPA), which underpinned additional guidance around MVPA in the context of high sedentary time. Finally, there was insufficient or low-certainty systematic review evidence on the type or domain of sedentary behaviour, or the frequency and/or duration of bouts or breaks in sedentary behaviour, to make specific recommendations for the health outcomes examined.

CONCLUSIONS

The WHO 2020 guidelines are based on the latest evidence on sedentary behaviour and health, along with interactions between sedentary behaviour and MVPA, and support implementing public health programmes and policies aimed at increasing MVPA and limiting sedentary behaviour. Important evidence gaps and research opportunities are identified.

Population Attributable Fraction of Established Modifiable Risk Factors on Colorectal Cancer in Korea

Purpose

We estimated the population attributable fraction (PAF) of established risk factors for colorectal cancer, to provide evidence for prioritizing cancer prevention policy.

Materials and Methods

The exposure prevalence was calculated by using data from the 2005 Korean National Health Examination Survey for tobacco smoking, alcohol consumption, obesity, physical inactivity, and meat intake. Risk estimates (relative risks) were selected from the published meta-analyses. Cancer incidence data from the Korea Central Cancer Registry were used to estimate the preventable number of colorectal cancer cases in 2015.

Results

The PAFs of the tobacco smoking, alcohol consumption, obesity, physical inactivity, and consumption of red and processed meat were as follows: 9.2%, 11.1%, 9.1%, 18.9%, and 10.1% for colon cancer and 21.8%, 12.3%, 3.5%, 5.3%, and 9.2% for rectal cancer among men; 1.0%, 1.3%, 2.7%, 12.3% and 9.2% for colon cancer and 1.7%, 2.3%, 0.8%, 7.2%, and 8.3% for rectal cancer among women. The PAFs of selected risk factors were 46.2% for colon and 42.4% for rectum among men, while 24.3% for colon and 18.9% for rectum among women. The attributable numbers of colon and rectal cancer to selected risk factors were 4,028 and 3,049 cases among men, respectively, while 1,644 and 778 cases among women in the year of 2015.

Conclusion

Changes in modifiable risk factors could prevent half of the colorectal cancer in the Korean population.

Physical Activity Clusters and Income Inequality in Brazilian Adults

Background: Income is an important determinant of physical activity (PA) when analyzed in its different domains. Sociodemographic characteristics such as sex, age, education, and marital status reveal distinct population profiles when PA domains are analyzed in isolation. This study aimed to describe clusters of PA in domains within income inequalities and to investigate the associated sociodemographic characteristics of Brazilian adults. Methods: A secondary analysis of the National Health Survey was performed (N = 50,176). PA, sociodemographic characteristics, and family income were investigated. Low- (n = 9504) and high-income adults (n = 6330) were analyzed. Two-step cluster and Rao–Scott chi-square tests were employed. Results: High-income adults accumulated 1.06 times more PA in leisure time compared with low-income adults. Of the 3 clusters observed, the inactive cluster was more prevalent (low-income group: 65.9%; 95% confidence interval [CI], 64.1–67.5; high-income group: 84.5%; 95% CI, 82.9–86.0). Work/leisure activities (21.2%; 95% CI, 19.8–22.8) and commuting/household activities (12.9%; 95% CI, 11.8–14.1) characterized low-income adults. Work/household activities (10.9%; 95% CI, 9.6–12.3) and commuting/leisure activities (4.6%, 95% CI, 3.9–5.4) characterized high-income adults. Sex (P < .001), age (P < .001), and marital status (P = .0023) were associated with low-income clusters. Conclusion: PA clustering differs within income inequalities. PA in leisure differentiates the opportunities in low- and high-income groups, but it is representative of a very small portion of the wealth.

Active travel and social justice: Addressing disparities and promoting health equity through a novel approach to Regional Transportation Planning

Public health impacts of transportation policies and infrastructure investment are becoming better understood, particularly for those associated with physical activity. Yet health impacts are not routinely evaluated within the context of the development of a Regional Transportation Plan (RTP) and subsequent programming and investment processes. This is particularly concerning because the spatial distribution of planned transportation infrastructure potentially has significant health equity implications for vulnerable populations at greater risk of chronic disease. This study discusses the application of the National Public Health Assessment Model (NPHAM) - a new approach that expands several scenario planning tools to include health - for the San Joaquin Council of Governments 2018 RTP. It demonstrates how quantifying health impacts at a finer spatial scale (census block groups) helps assess the extent to which RTP strategies are likely to benefit or harm health. It further enables a spatial form of health equity analysis that can help planners understand where infrastructure is most needed to meet social equity goals. To the knowledge of the authors, this is the first example of a quantified, health equity analysis of transport physical activity and a health outcome - body mass index - associated with an RTP; it demonstrates significant advancement in transportation planning practice and policy.

Influence of physical activity at a young age and lifetime physical activity on the risks of 3 obesity-related cancers: systematic review and meta-analysis of observational studies

CONTEXT

Excess weight has been linked to increased risks of 13 types of cancers. Physical activity is a non-nutritional modifiable lifestyle factor that is not only crucial for weight control but is also known to regulate hormones and metabolic pathways that may contribute to carcinogenesis. There is solid evidence that being physically active during middle and late adulthood lowers the risks of 3 obesity-related cancers, namely breast cancer, colon cancer, and endometrial cancer. However, the associations between physical activity at a young age (childhood, adolescence, and young adulthood; age 5 to ≤30 yr) and lifetime physical activity and the risks of breast cancer, colon cancer, and endometrial cancer are less defined.

OBJECTIVE

The present systematic review and meta-analysis of observational studies was performed in accordance with the MOOSE guidelines to determine whether physical activity at a young age and lifetime physical activity may lower the risks of breast cancer, colon cancer, and endometrial cancer.

DATA SOURCES

The PubMed and Web of Science databases were searched for relevant observational studies published from inception to July 2018.

STUDY SELECTION

Observational studies (prospective cohort, case-cohort, nested case-control, historical cohort, and case-control) were considered relevant if they investigated the association between physical activity at a young age or lifetime physical activity and the risks of developing selected cancers.

DATA EXTRACTION

A random-effects meta-analysis was performed to generate the summary relative risk (RR) with 95%CI for the highest vs the lowest category of physical activity of any type.

RESULTS

Eighty publications were included in the present meta-analysis. Higher physical activity at a young age was associated with lower risks of breast cancer (RR 0.81, 95%CI 0.76, 0.87) and colon cancer (RR 0.67, 95%CI 0.50, 0.88). Similarly, lifetime physical activity was inversely associated with the risks of breast cancer (RR 0.79, 95%CI 0.72, 0.86) and colon cancer (RR 0.75, 95%CI 0.69, 0.82). For breast cancer, menopausal status did not appear to modify the observed inverse association. The benefit with respect to endometrial cancer risk reduction was only observed with higher lifetime physical activity (RR 0.77, 95%CI 0.67, 0.88), not with higher physical activity at a young age (RR 0.89, 95%CI 0.73, 1.07).

CONCLUSIONS

Being physically active over a lifetime, starting from early childhood, may lower the risks of developing breast cancer, colon cancer, and endometrial cancer.

The association between recreational screen time and cancer risk: findings from the UK Biobank, a large prospective cohort study

Background

Evidence is suggestive of sedentary behaviour being associated with an increased risk of endometrial cancer, but the evidence base is too limited to draw any conclusions for other cancers. The aim of the study was to investigate the association between recreational screen time and site-specific cancer risk.

Methods

We analysed data from the prospective UK Biobank cohort study. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for associations between daily recreational screen time (including television (TV) viewing time, computer use time and total screen time) and site-specific cancer risk. Partition models and isotemporal substitution models investigated the impact of substituting recreational screen time with physical activity.

Results

During a mean follow-up of 7.6 years, 28,992 incident cancers were identified among 470,578 adults. A 1-h increase in daily TV viewing time was associated with higher risks of oropharyngeal, oesophago-gastric and colon cancer in fully adjusted models. Participants who reported ≤1, compared with 1- ≤ 3, hours/day of TV viewing time had lower risks of lung, breast, and oesophago-gastric cancer. Findings were inconsistent for daily recreational computer use and daily total recreational screen time. The majority of observed associations were small, and were attenuated after excluding cancers diagnosed within the first two years of follow-up, except for oesophago-gastric and colon cancers (HR 1.05, 95% CI: 1.01, 1.10; and HR 1.04, 95% CI: 1.01, 1.07 per 1-h increase in daily TV viewing time, respectively). However, isotemporal substitution models showed reduced risk of some site-specific (oropharyngeal, lung, breast and colorectal) cancers when replacing 1-h/day of TV viewing with 1-h of moderate-intensity physical activity or walking.

Conclusions

Our findings show that daily recreational screen time, particularly TV viewing, was associated with small increased risks of oesophago-gastric and colon cancer. Replacing 1-h/day of TV viewing with 1-h of moderate-intensity physical activity or walking was associated with lower risk of oropharyngeal, lung, breast and colorectal cancers. Further research from other large prospective cohort studies is required, while mechanistic research is warranted to enhance the biological plausibility of these findings.

The Influence of Sedentary Behavior on Cancer Risk: Epidemiologic Evidence and Potential Molecular Mechanisms

PURPOSE OF REVIEW

Sedentary behavior is an emerging risk factor for several cancers. Here, we review the current epidemiologic evidence on sedentary behavior and cancer risk and summarize potential underlying molecular mechanisms.

RECENT FINDINGS

High compared to low sedentary behavior is associated with a 28-44% increased risk of colon cancer, a 8-17% increased risk of breast cancer, and a 28-36% increased risk of endometrial cancer. For other cancer sites, the current evidence is insufficient, mainly due to sparse numbers of available studies. Potential underlying biologic mechanisms linking prolonged sedentary behavior to increased cancer risk include metabolic dysfunction, alterations in circulating levels of sex hormones, and low-grade systemic chronic inflammation. Prolonged sedentary behavior is positively related to cancers of the colon, breast, and endometrium. For other cancer types, the current evidence is inconclusive. Underlying biological mechanisms are poorly understood and need to be an integral part of future research.

Do low-fat foods alter risk of colorectal cancer from processed meat?

OBJECTIVES

We investigated potential causes of the high incidence rate of colorectal cancer (CRC) in New Zealand.

STUDY DESIGN

A national population-based case-control study of 806 cases and 1025 controls was conducted to determine the risk factors for CRC in this population.

METHODS

Information about family history of CRC, ethnicity, diet, school milk consumption, exercise, and height and weight at age 20 years were collected by a self-administered questionnaire from cases and controls.

RESULTS

Response rates were 84% for cases and 65% for controls. Increasing preference for low-fat food alternatives was associated with reducing odds ratios (OR) for CRC (P_trend<0.001) with a considerably reduced OR of always versus never choosing low-fat food alternatives (OR = 0.39, 95% confidence interval = 0.26, 0.58). Increased consumption of dairy products or milk was associated with reduced risk of CRC. Belonging to the male gender, having a first degree relative with CRC, and increasing consumption of processed meat, lamb, pork, and bread were associated with elevated risks of CRC. The increased risk from consumption of processed meat was not evident in subjects who regularly or always preferred low-fat food.

CONCLUSIONS

A preference for low-fat food may ameliorate an increased risk of CRC from the consumption of processed meat.

Perceptions of an online 'train-the-champion' approach to increase workplace movement

Prolonged sitting is now recognized as an emergent work health and safety issue. To address the need for a scalable sitting-reduction intervention for workplaces, the BeUpstanding™ Champion Toolkit was developed. This free, online toolkit uses a 'train-the-champion' approach, providing a step-by-step guide and resources to workplace champions to assist them in raising awareness and building a supportive culture to reduce sitting time in their team. This qualitative study explored champion and staff perceptions of the beta (test) version of the toolkit. Seven work teams, from a range of workplace sectors (blue-/white-collar), sizes (small/medium/large) and locations (urban/regional) participated; all team members were exposed to the program (n = 603). Approximately 4 months after program initiation, semi-structured interviews were conducted with all champions (n = 7); focus groups were conducted with a random sample of staff (n = 40). Champions were followed-up again at 12 months (n = 5). Transcripts were coded by two researchers, with codes organized into overarching themes. All champions found the 'train-the-champion' approach, and the toolkit acceptable. Common enablers for intervention delivery included: champion passion for staff health and wellbeing; perceived fit of the program within existing practice; and, management support. Champions and staff reported improvements in knowledge/awareness about sitting, cultural norms, perceived stress, productivity and resilience. Facilitators for sustained change over time included a stable organizational climate and ongoing management support; barriers included workload intensification. The beta version of the BeUpstanding™ Champion Toolkit was highly acceptable to workplace champions and staff, and was perceived to have benefits for team culture and staff knowledge and wellbeing.

American College of Sports Medicine Roundtable Report on Physical Activity, Sedentary Behavior, and Cancer Prevention and Control

INTRODUCTION

The American College of Sports Medicine convened an International Multidisciplinary Roundtable on Exercise and Cancer in March 2018 to evaluate and translate the evidence linking physical activity and cancer prevention, treatment, and control. This article discusses findings from the Roundtable in relation to the biologic and epidemiologic evidence for the role of physical activity in cancer prevention and survival.

RESULTS

The evidence supports that there are a number of biologically plausible mechanisms, whereby physical activity can influence cancer risk, and that physical activity is beneficial for the prevention of several types of cancer including breast, colon, endometrial, kidney, bladder, esophageal, and stomach. Minimizing time spent in sedentary behavior may also lower risk of endometrial, colon and lung cancers. Conversely, physical activity is associated with higher risk of melanoma, a serious form of skin cancer. Further, physical activity before and after a cancer diagnosis is also likely to be relevant for improved survival for those diagnosed with breast and colon cancer; with data suggesting that postdiagnosis physical activity provides greater mortality benefits than prediagnosis physical activity.

CONCLUSIONS

Collectively, there is consistent, compelling evidence that physical activity plays a role in preventing many types of cancer and for improving longevity among cancer survivors, although the evidence related to higher risk of melanoma demonstrates the importance of sun safe practices while being physically active. Together, these findings underscore the importance of physical activity in cancer prevention and control. Fitness and public health professionals and health care providers worldwide are encouraged to spread the message to the general population and cancer survivors to be physically active as their age, abilities, and cancer status will allow.

Occupational, Transport, Leisure-Time, and Overall Sedentary Behaviors and Their Associations with the Risk of Cardiovascular Disease among High-Tech Company Employees

This study examined the associations of overall and domain-specific (i.e., occupational, transport, and leisure-time) sedentary behaviors with cardiovascular disease (CVD) risk factors among high-tech company employees in Taiwan. A total of 363 participants employed at high-tech companies (mean age ± standard deviation: 37.4 ± 7.2 years) completed a questionnaire administered by email regarding their overall, occupational, transport, and leisure-time sedentary behaviors. Self-reported data of height and weight, blood pressure, blood sugar, and total cholesterol levels were also collected in 2018. An adjusted binary logistic regression model was employed in the analysis. After adjusting for sociodemographic variables, high-tech company employees who used a computer (or Internet) for more than 2 h per day during their leisure time were more likely to have CVD risk factors (odds ratio: 1.80; 95% confidence interval: 1.08-3.00). No significant associations with CVD risk factors were detected for total sedentary time, occupational sitting, television viewing time, and transport-related sitting. Despite the nature of cross-sectional design in this study, our findings may have considerable implications for intervention designers and policymakers of Taiwan. Developing effective strategies for limiting leisure-time computer use should be considered for the prevention of CVD among high-tech company employees.

Active Lifestyle Patterns Reduce the Risk of Colorectal Cancer in the North of Vietnam: A Hospital-Based Case-Control Study

A hospital-based, case-control study was conducted to investigate the association between lifestyle patterns and risk of colorectal cancer (CRC) in the north of Vietnam. Demographic factors employed for the models were age, sex, marital status, occupation, education, income, smoking status, alcohol consumption, vegetable consumption, tea, coffee consumption, and physical activity (PA). Individuals of both groups (n = 154 for the control group and n = 136 for the CRC group) were interviewed using a questionnaire by trained interviewers. The findings showed that moderate PA was inversely associated with CRC risk: odds ratio (OR) = 0.19, 95% confidence interval (CI) = 0.10 to 0.36 with P < .01. The total PA showed that the highest tertile (>2.7 MET-h/d) was associated with the reduced risk of CRC compared with the lowest tertile one after controlling for confounding factors: adjusted OR = 0.25, 95% CI = 0.09 to 0.74, P < .01. Sedentary time was associated with an increased level of CRC risk by 57% as compared between the highest tertile and the lowest one after controlling for confounding factors. Daily consumption of vegetables and 1 to 3 cups of tea per day or more were also associated with decreased risk of CRC. Despite promising findings, a limitation of this research is that it did not establish a temporal relationship between risk factors and CRC due to its retrospective design. However, this is the first analytic study highlighting the role of the active lifestyle pattern associated with reduced CRC risk in Vietnamese adults.

Deaths from colon cancer among farmers in Taiwan: a mortality odds ratio study

Few studies have examined the association between increased risk of colon cancer development and occupation of farming. Data thus far have been inconsistent with respect to a correlation between farming and colon cancer occurrence. This type of study has not been undertaken in Asia. The aim of this investigation was to utilize the mortality odds ratio (MOR) design to estimate the relative risk (RR) of mortality attributed to colon cancer in farmers in Taiwan. Utilizing Taiwan's Death Certificate Registry, data were collected on subjects who died between 1997-2009. Our study group was comprised of individuals 50 years of age and higher who died of colon cancer, while the control group consisted of subjects the same age who died of all other causes excluding cancers. Multiple logistic regression was performed to compute the MOR adjusted for gender, age at death, year of death, marital status, and urbanization levels. Of the 32,456 farmers who died, 558 were attributed to die of colon cancer. Farmers in Taiwan had a significantly lower risk of mortality from colon cancer than non-farmers (MOR = 0.85, 95% CI = 0.78-0.93), similar to estimates reported in previous meta-analyses. Occupational physical activity or higher consumption of vegetables and fruits might have contributed to the lower risk of death due to colon cancer. The basis for these observations requires further examination as it appears that lifestyle is a crucial factor in colon cancer development.

Revisiting the impact of lifestyle on colorectal cancer risk in a gender perspective

Colorectal cancer (CRC) is a leading cause of cancer-related mortality in the world. Patterns and trends in CRC incidence and mortality correlate with increasing adoption of Western lifestyles and with the overweight/obesity epidemic. Both genetic background and a range of modifiable environmental/lifestyle factors play a role in CRC etiology. Among these the links of body weight, dietary patterns and physical activity (PA) behavior with CRC risk are some of the strongest for any type of cancer, with a different impact in women and men. Nonetheless, gender disparities still represent a neglected aspect of CRC management. This review sheds light on gender-related association of obesity and different dietary/PA habits with CRC risk, highlighting the importance of lifestyle modifications in the prevention of this neoplastic disease. In this scenario, intervention studies are strongly recommended to define the most effective dietary/PA regimens for primary prevention of cancer in women and men.