Physical activity, obesity and sedentary behaviour and the risks of colon and rectal cancers in the 45 and up study

Barriers and facilitators of physical activity among Latina immigrant and Mexican mothers living in the US and Mexico: A qualitative study

Latina immigrant women are among the least physically active when compared with women in other racial/ethnic groups in the US. Similarly, Mexican mothers in Mexico have low rates of physical activity. Motherhood and immigration experiences are recognized barriers to engage in physical activity among Latina immigrant mothers. Less is known about the factors that promote and limit physical activity engagement among Mexican mothers in Mexico, and how their experiences compare with their immigrant counterparts. This transnational qualitative study aimed to investigate the barriers and facilitators of physical activity of 25 Latina mothers in Mexico and the US. Low-income Mexican mothers of kindergarten aged children and Latino mothers of similar aged children were recruited in San Luis Potosí, Mexico and central Illinois, US. Semi-structured interviews were administered by two bilingual and bicultural researchers in participants language of preference. Interviews were transcribed verbatim and analyzed using a thematic network approach and multi-stage coding analysis guided by the Socio-Ecological Model framework. We found that at the macro-level: 1) familial obligations, and 2) cold weather after migrating; at the mezzo-level: 1) changes in walking patterns, and 2) social cohesion (e.g., lack of an invitation to engage in activities); and at the micro-level: 1) individual perceptions, particularly unattainable perceptions of physical activity and 2) shift exhaustion were perceived as barriers and occasionally facilitators of physical activity by mothers in both countries. Context-specific interventions are needed to increase women's physical activity levels in the US and Mexico.

Influence of the duration of type 2 diabetes mellitus on colorectal cancer outcomes

Type 2 diabetes mellitus (T2DM) is a progressive disease, which affects colorectal cancer (CRC) survival. However, data on the relationship between CRC survival and T2DM duration is scarce and controversial. A retrospective observational study was conducted. Sub-cohorts were created based on the duration of T2DM as follows, ≤ or > 5/10/15/20 years. 204 of the 817 (24.95%) included study participants had T2DM at any point of CRC. 160 of the 204 CRC + T2DM patients had detailed T2DM duration data. At the time of CRC diagnosis, 85, 50, 31, and 11 patients had T2DM for > 5/10/15/20 years, respectively, which increased to 110, 71, 45, and 17 during the course of the study. Despite constant glycated hemoglobin values throughout the study, shorter overall and disease-specific survival times were observed for the > 5/10/15 years cohorts and longitudinal survival modeling techniques confirmed the significant effect of T2DM duration in all cohorts. While in the first 3 years after CRC diagnosis, the best survival was found for the ≤ 5 years cohort, all diabetes cohorts had the same survival thereafter. T2DM duration affected CRC survival significantly, therefore, a closer follow-up of this sub-populations is suggested.

Non-occupational physical activity and risk of cardiovascular disease, cancer and mortality outcomes: a dose-response meta-analysis of large prospective studies

OBJECTIVE

To estimate the dose-response associations between non-occupational physical activity and several chronic disease and mortality outcomes in the general adult population.

DESIGN

Systematic review and cohort-level dose-response meta-analysis.

DATA SOURCES

PubMed, Scopus, Web of Science and reference lists of published studies.

ELIGIBILITY CRITERIA

Prospective cohort studies with (1) general population samples >10 000 adults, (2) ≥3 physical activity categories, and (3) risk measures and CIs for all-cause mortality or incident total cardiovascular disease, coronary heart disease, stroke, heart failure, total cancer and site-specific cancers (head and neck, myeloid leukaemia, myeloma, gastric cardia, lung, liver, endometrium, colon, breast, bladder, rectum, oesophagus, prostate, kidney).

RESULTS

196 articles were included, covering 94 cohorts with >30 million participants. The evidence base was largest for all-cause mortality (50 separate results; 163 415 543 person-years, 811 616 events), and incidence of cardiovascular disease (37 results; 28 884 209 person-years, 74 757 events) and cancer (31 results; 35 500 867 person-years, 185 870 events). In general, higher activity levels were associated with lower risk of all outcomes. Differences in risk were greater between 0 and 8.75 marginal metabolic equivalent of task-hours per week (mMET-hours/week) (equivalent to the recommended 150 min/week of moderate-to-vigorous aerobic physical activity), with smaller marginal differences in risk above this level to 17.5 mMET-hours/week, beyond which additional differences were small and uncertain. Associations were stronger for all-cause (relative risk (RR) at 8.75 mMET-hours/week: 0.69, 95% CI 0.65 to 0.73) and cardiovascular disease (RR at 8.75 mMET-hours/week: 0.71, 95% CI 0.66 to 0.77) mortality than for cancer mortality (RR at 8.75 mMET-hours/week: 0.85, 95% CI 0.81 to 0.89). If all insufficiently active individuals had achieved 8.75 mMET-hours/week, 15.7% (95% CI 13.1 to 18.2) of all premature deaths would have been averted.

CONCLUSIONS

Inverse non-linear dose-response associations suggest substantial protection against a range of chronic disease outcomes from small increases in non-occupational physical activity in inactive adults. PROSPERO registration number CRD42018095481.

Body fatness associations with cancer: evidence from recent epidemiological studies and future directions

This narrative review highlights current evidence linking greater body fatness to risk of various cancers, with focus on evidence from recent large cohort studies and pooled analyses of cohort studies as well as Mendelian randomization studies (which utilized genetic variants associated with body mass index to debrief the causal effect of higher body fatness on cancer risk). This review also provides insights into the biological mechanisms underpinning the associations. Data from both observational and Mendelian randomization studies support the associations of higher body mass index with increased risk of many cancers with the strongest evidence for digestive system cancers, including esophageal, stomach, colorectal, liver, gallbladder, and pancreatic cancer, as well as kidney, endometrial, and ovarian (weak association) cancer. Evidence from observational studies suggests that greater body fatness has contrasting effects on breast cancer risk depending on menopausal status and on prostate cancer risk depending on disease stage. Experimental and Mendelian randomization studies indicate that adiponectin, insulin, and sex hormone pathways play an important role in mediating the link between body fatness and cancer risk. The possible role of specific factors and pathways, such as other adipocytokines and hormones and the gut microbiome in mediating the associations between greater body fatness and cancer risk is yet uncertain and needs investigation in future studies. With rising prevalence of overweight and obesity worldwide, the proportion of cancer caused by excess body fatness is expected to increase. There is thus an urgent need to identify efficient ways at the individual and societal level to improve diet and physical activity patterns to reduce the burden of obesity and accompanying comorbidities, including cancer.

Risk Factors for Colorectal Adenocarcinoma in an Indigenous Population in East Africa

Introduction

The incidence of colorectal cancer (CRC) is increasing in East Africa. Changes in lifestyle and dietary changes, particularly alcohol consumption, smoking, and consumption of cooked meats with a reduction in fibre in the diet may be responsible. The objective of our study was to determine the risk factors responsible for CRC in Uganda.

Methods

We recruited 129 participants with histologically proven colorectal adenocarcinoma and 258 control participants from four specialized hospitals in central Uganda from 2019 to 2021. Controls were block matched for age (±5 years) and sex of the case participants. The risk factor variables included; area of residence, tribe, body mass index (BMI), smoking, alcohol consumption and family history of gastrointestinal cancer. We used conditional or ordinal logistic regression to obtain crude and adjusted odds ratios for risk factors associated with CRC.

Results

In bivariate analysis, case participants were more likely to be associated with urban residence (cOR:62.11; p<0.001); family history of GI cancer (cOR: 14.34; p=0.001); past smokers (cOR: 2.10; p=0.080); past alcohol drinkers (cOR: 2.35; p=0.012); current alcohol drinkers (cOR: 3.55; p<0.001); high BMI 25–29.9 kg/m² (cOR: 2.49; p<0.001); and high BMI ≥30kg/m² (cOR: 2.37; p=0.012). In the multivariate analysis, urban residence (aOR: 82.79; p<0.001), family history of GI cancer (aOR: 61.09; p<0.001) and past smoking (aOR: 4.73; p=0.036) were independently associated with a higher risk of developing CRC.

Conclusion

A family history of gastrointestinal cancer was a risk factor for CRC. While population-based CRC screening may not be feasible in low income-countries, targeted CRC screening for first-degree relatives with CRC should be considered in East Africa. Molecular genetic studies need to be carried out to determine the role of hereditary factors in our population. Prevention strategies should be adopted to avoid smoking in our population which was associated with an increased risk of CRC.

Colorectal cancer pain upon diagnosis and after treatment: a cross-sectional comparison with healthy matched controls

BACKGROUND

The current study sought to explore whether cancer pain (CP) already exists in patients at colorectal cancer (CRC) diagnosis before treatment compared with patients with colorectal cancer (CRC) after treatment and a healthy matched control group. The study also sought to examine whether factors related to physical health status could enhance pain processes.

METHODS

An observational cross-sectional study was conducted following the STROBE checklist. Twenty-nine newly diagnosed and forty post-treatment patients with CRC and 40 healthy age/sex-matched controls were included for comparison. Pain, local muscle function, and body composition outcomes were assessed by a physiotherapist with > 3 years of experience. ANCOVA and Kruskal-Wallis tests were performed, with Bonferroni and Dunn-Bonferroni post hoc analyses and Cohen's d and Hedge's effect size, as appropriate.

RESULTS

The analysis detected lower values of pressure pain threshold (PPT) points, the PPT index, and abdominal strength and higher values of self-reported abdominal pain in newly diagnosed patients, with even more marked results observed in the post-treatment patients, where lower lean mass and skeletal muscle index values were also found than those in the healthy matched controls (p < 0.05). In the post-treatment and healthy matched control groups, positive associations were observed between the PPT lumbar dominant side points and abdominal isometric strength and lean mass, and negative associations were observed between the lumbar dominant side points and body fat (p < 0.05).

CONCLUSION

Upon diagnosis, patients with CRC already show signs of hyperalgesia and central sensitization and deteriorated physical conditions and body composition, and this state could be aggravated by subsequent treatments.

Risk Factors for the Diagnosis of Colorectal Cancer

BACKGROUND

Colorectal cancer defined as cancer of the colon or rectum, is the third most frequently diagnosed cancer in men and the second in women, and, according to the World Health Organization database GLOBOCAN, it accounts for nearly 1.4 million new cases annually worldwide. The occurrence of colorectal cancer is associated with nonmodifiable risk factors, including age and hereditary factors, as well as with modifiable environmental and lifestyle factors.

METHODS

The study included 800 patients, 400 diagnosed with colorectal cancer and 400 within the control group, who gave their written informed consent to participate in the study. Patients with cancer other than colorectal cancer were randomly selected for control group I, and patients with no cancer diagnosis were selected for control group II. The method used was a case-control study - an observational and analytical study with a control group, conducted among patients of the Clinical Oncology Centre and the Provincial Hospital in the years 2019-2020. The study comparing the exposure was carried out in a group of people who developed the endpoint, that is colorectal cancer, with the exposure in a well-matched group of controls who did not reach the endpoint. Assessment of activity and BMI was used according to WHO recommendations, as well as the expert system. The data were tested for the distribution and the homogeneity of variance was validated before applying the parameter tests. Comparison of quantitative variables between groups was performed using ANOVA.

RESULTS

The mean age of the patients was 64.53 ± 8.86 years, of the control group I - 59.64 ± 9.33 and the control group II - 57.5 (7.83). There was a strong positive association between the incidence of ulcerative colitis and the risk of colorectal cancer (P < .01). Among obese subjects, the risk of developing colorectal cancer was 1.27 (95% CI, 1.06-1.53) compared with nonobese subjects. A strong positive relationship was found between low physical activity converted to metabolic equivalent of MET effort per week and the risk of colorectal cancer (P < .001). The relative risk for current smokers was 2.17 (95% CI 1.79-2.66). There was an association between higher fat consumption and higher red meat consumption and the risk of developing colorectal cancer (P < .01).

CONCLUSIONS

Obesity, low physical activity, active and passive smoking and high salt and red meat consumption have been associated with an increased risk of colorectal cancer. These findings provide further evidence of the importance of maintaining a healthy lifestyle.

Adverse associations of sedentary behavior with cancer incidence and all-cause mortality: A prospective cohort study

BACKGROUND

Inconsistent results have been reported in developed countries for relationships between sedentary behavior and cancer incidence and mortality, and evidence from the Chinese population is scarce. This study aimed to investigate such relationships in large Chinese population-based prospective cohorts and to explore the joint effect and interaction of sedentary behavior and moderate-to-vigorous physical activity (MVPA) on these relationships.

METHODS

We included 95,319 Chinese adults without cancer from 3 large cohorts and assessed their sedentary behavior and physical activity with a unified questionnaire. Cancer incidence and mortality were confirmed by interviewing participants or their proxies and checking hospital records and death certificates. Hazard ratios (HRs) and 95% confidence intervals (95%CIs) for cancer and mortality were estimated using Cox proportional hazards regression models.

RESULTS

During 559,002 person-years of follow-up, 2388 cancer events, 1571 cancer deaths, and 4562 all-cause deaths were recorded. Sedentary behavior was associated with increased risk of developing cancer and deaths in a dose-response manner. The multivariable-adjusted HRs (95%CIs) were the following: HR = 1.16, 95%CI: 1.01‒1.33; HR = 1.24, 95%CI: 1.04‒1.48; and HR = 1.15, 95%CI: 1.04‒1.28 for cancer incidence, cancer mortality, and all-cause mortality, respectively, for those having ≥10 h/day of sedentary time compared with those having <6 h/day of sedentary time. Sedentary populations (≥10 h/day) developed cancer or died 4.09 years and 2.79 years earlier, respectively, at the index age of 50 years. Failure to achieve the recommended level of MVPA may further aggravate the adverse associations, with the highest cancer and mortality risks being observed among participants with both ≥10 h/day of sedentary time and <150 min/week of MVPA. Limitations of this study include the fact that physical activity information was obtained via questionnaire instead of objective measurement and that there were insufficient incident cases for the analysis of associations between sedentary behavior and site-specific cancers.

CONCLUSION

Sedentary behavior was associated with an increased risk of cancer and all-cause mortality among Chinese adults, especially for those with ≥10 h/day of sedentary time. It is necessary to reduce sedentary time, in addition to increasing MVPA levels, for the prevention of cancer and premature death.

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.

Prevalence of accelerometer-measured physical activity in adolescents in Fit Futures - part of the Tromsø Study

BACKGROUND

Previous studies show large variations in physical activity (PA) levels among adolescents. However, the number of studies is limited and even fewer studies have assessed PA in adolescents by accelerometer devices. This study aimed to describe accelerometer-measured PA levels in adolescents in a population-based cohort in Northern Norway.

METHODS

In 611 students aged 16-17 years attending the Fit Futures Study, PA was measured by Actigraph GT3X for seven consecutive days. PA was expressed as total PA volume (counts per minute, CPM), time spent in intensity zones, steps per day, and fulfilment of WHO recommendation (i.e. accumulation of 60 min or more of at least moderate intensity PA per day). Potential correlates of PA such as sex, socioeconomic status, study program, self-perceived health, and PA variations by weekday versus weekend were also examined.

RESULTS

16% of the girls and 25% of the boys fulfilled current WHO-recommendations. Total PA volume (CPM) was higher in boys than in girls (353 (SD 130) versus 326 (SD 114) CPM, p < 0.05). PA levels differed with study program and increased with better self-perceived health, but were not associated with socioeconomic status. Both boys and girls were more active on weekdays than weekends (altogether; 350 (SD 124) versus 299 (SD 178) CPM, p < 0.05).

CONCLUSIONS

In this cohort of adolescents, less than 25% of 16-17-year-old boys and girls fulfilled the WHO recommendations. The levels of physical activity in 16-17-year-old adolescents are similar to previous data reported in adults.

Barriers to colorectal cancer screening for people with spinal cord injuries and/or disorders: A qualitative study

BACKGROUND

Limited research has shown people with spinal cord injuries and/or disorders (SCID) are less likely to be up to date with colorectal cancer (CRC) screening and therefore more likely to be diagnosed with advanced stage CRC compared to people without SCID.

OBJECTIVE

The aims of this study were to assess knowledge about CRC, CRC screening, and self-reported barriers to CRC screening for people with SCID.

METHODS

Interviews with 30 individuals with SCID were conducted using a semi-structured interview guide, audio recorded, and transcribed. Coding was performed using a hybrid approach of inductive and deductive analysis. Thematic analysis was used to identify, review, and modify themes and sub-themes.

RESULTS

Themes identified included barriers to CRC screening, such as socioeconomic, health system, transportation, psychological, and environmental or accessibility barriers. While most respondents were able to describe one CRC screening method (usually colonoscopy), knowledge of other screening modalities was limited. Low CRC literacy and misinformation about CRC screening appeared to increase respondent association between CRC screening and colonoscopy. While most respondents associated CRC screening with colonoscopy, almost half reported the colonoscopy preparation was the most substantial barrier to screening.

CONCLUSIONS

In addition to addressing identified barriers such as accessibility and transportation, communication, and prevention interventions should be specifically targeted to ensure all people with SCID are informed about appropriate and various modalities and the benefits of screening. Specific, evidence-based guidelines on the use of stool specimens first with follow up direct visualization, if needed, should be developed for this population.

Early-onset colorectal cancer: initial clues and current views

Over the past several decades, the incidence of early-onset colorectal cancer (EOCRC; in patients <50 years old) has increased at an alarming rate. Although robust and scientifically rigorous epidemiological studies have sifted out environmental elements linked to EOCRC, our knowledge of the causes and mechanisms of this disease is far from complete. Here, we highlight potential risk factors and putative mechanisms that drive EOCRC and suggest likely areas for fruitful research. In addition, we identify inconsistencies in the evidence implicating a strong effect of increased adiposity and suggest that certain behaviours (such as diet and stress) might place nonobese and otherwise healthy people at risk of this disease. Key risk factors are reviewed, including the global westernization of diets (usually involving a high intake of red and processed meats, high-fructose corn syrup and unhealthy cooking methods), stress, antibiotics, synthetic food dyes, monosodium glutamate, titanium dioxide, and physical inactivity and/or sedentary behaviour. The gut microbiota is probably at the crossroads of these risk factors and EOCRC. The time course of the disease and the fact that relevant exposures probably occur in childhood raise important methodological issues that are also discussed.

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.

Physically active individuals have a 23% lower risk of any colorectal neoplasia and a 27% lower risk of advanced colorectal neoplasia than their non-active counterparts: systematic review and meta-analysis of observational studies

BACKGROUND

Few studies have examined the associations between physical activity (PA), sedentary behaviour (SB) and risk of colorectal neoplasia (CN).

METHODS

We systematically searched Medline, Embase, PsyInfo, Cochrane and other sources from their inception to 30 September 2018 for cohort, case-control and cross-sectional studies that evaluated these associations in asymptomatic, average-risk subjects. Random-effect models were used to estimate relative risks (RRs) of any-type CN, advanced CN, and non-advanced CN, respectively, in individuals with the highest versus the lowest level of PA and SB. Dose-response analyses and subgroup analyses were conducted. The I² statistic was used to examine heterogeneity among studies.

RESULTS

We identified 32 observational studies, including 17 cross-sectional studies, 10 case-control studies and five longitudinal studies. PA (highest vs lowest) was inversely associated with risk for any-type CN (n=23 studies) and advanced CN (n=15 studies), with a RR of 0.77 (95% CI=0.71 to 0.83, I²=57.5%) and 0.73 (95% CI=0.63 to 0.82, I²=45.5%), respectively. There was no association between PA and non-advanced CN (n=5 studies). There was an as association between PA and any-type CN in both sexes, and also for the distal colon. We found no dose-response relationship between PA and any-type or advanced CN. Based on three studies identified, SB time (longest vs shortest) was associated with an increased risk of advanced CN (RR=1.24, 95% CI 1.04 to 1.49, I²=14.4%). No publication bias was detected by Begg's test.

CONCLUSION

We report a 23% lower relative risk of any type of CN and a 27% lower risk of advanced CN in people with the highest level of PA compared with those in the lowest.

Correlation of Barrett's esophagus with colorectal polyps in Japanese patients: A retrospective chart review

BACKGROUND AND AIM

Barrett's esophagus and colorectal polyps have several overlapping risk factors. Whereas several reports in Western countries have indicated a close relationship between Barrett's esophagus and colorectal polyps, the relationship between these two diseases remains unclear in Japan. This study was performed to determine whether the prevalence of Barrett's esophagus is related to that of colorectal polyps in Japanese patients.

METHODS

The present retrospective chart review included 1582 Japanese patients who underwent both total colonoscopy and esophagogastroduodenoscopy from January 2010 to December 2016. The data on colorectal polyps and Barrett's esophagus were obtained from the endoscopic findings. The medical record of each patient was checked for age, sex, body mass index, smoking, alcohol drinking, use of acid suppression agents, and comorbidities including a history of diabetes, ischemic heart disease, gastroesophageal reflux disease, hiatal hernia, and Helicobacter pylori infection.

RESULTS

Colorectal polyps were detected in 789 of the 1582 patients (49.9%). Barrett's esophagus was detected in 233 patients (14.7%), and most cases of Barrett's esophagus (n = 229) were classified as short-segment Barrett's esophagus. Colorectal polyps were more frequent in patients with than without Barrett's esophagus (odds ratio, 1.79; 95% confidence interval, 1.31-2.46; P < 0.001). In addition to Barrett's esophagus, the data indicated that old age, male sex, obesity, smoking, alcohol drinking, diabetes mellitus, and ischemic heart disease were independent risk factors for colorectal polyps.

CONCLUSIONS

The present study revealed the correlation between the prevalence of Barrett's esophagus and colorectal polyps in Japanese patients.

Going to extremes: determinants of extraordinary response and survival in patients with cancer

Research into factors affecting treatment response or survival in patients with cancer frequently involves cohorts that span the most common range of clinical outcomes, as such patients are most readily available for study. However, attention has turned to highly unusual patients who have exceptionally favourable or atypically poor responses to treatment and/or overall survival, with the expectation that patients at the extremes may provide insights that could ultimately improve the outcome of individuals with more typical disease trajectories. While clinicians can often recount surprising patients whose clinical journey was very unusual, given known clinical characteristics and prognostic indicators, there is a lack of consensus among researchers on how best to define exceptional patients, and little has been proposed for the optimal design of studies to identify factors that dictate unusual outcome. In this Opinion article, we review different approaches to identifying exceptional patients with cancer and possible study designs to investigate extraordinary clinical outcomes. We discuss pitfalls with finding these rare patients, including challenges associated with accrual of patients across different treatment centres and time periods. We describe recent molecular and immunological factors that have been identified as contributing to unusual patient outcome and make recommendations for future studies on these intriguing patients.

Variation in Nordic Work-Related Cancer Risks after Adjustment for Alcohol and Tobacco

Background: Alcohol and tobacco strongly increases the risk of cancers of the tongue, mouth, pharynx, larynx, and oesophagus, and are also established risk factors for cancer of the liver, colon, and rectum. It is well documented that these habits are unequally distributed among occupational groups. Most occupational cohort studies lack information on these potentially important confounders, and may therefore be prone to bias. Aim: The aim of the study is to present Nordic standardized incidence ratios (SIRs) for alcohol and tobacco related cancer by occupation, after adjustment for alcohol and tobacco, and to compare to the unadjusted SIRs. Material and Methods: The study is based on the Nordic Occupational Cancer (NOCCA) database. We used confirmatory factor analysis models for simultaneous analysis of the cancer sites related to alcohol and tobacco, to obtain factors that allow for computation of adjusted expected numbers from the reference rates. We then calculated adjusted SIRs for the relevant cancer sites for each occupation. Results: For some occupations and cancers, the changes of risk estimates were striking, from significantly high to significantly low and vice versa. Among Nordic farmers, unadjusted SIRs for cancer of the mouth and oesophagus were 0.56 (95% confidence interval (CI) 0.51⁻0.61) and 0.67 (CI 0.63⁻0.70), respectively. After adjustment, estimates changed to 1.10 (CI 1.01⁻1.21) and 1.16 (CI 1.10⁻1.22). Unadjusted SIR for pharynx cancer among wood workers was 0.83 (CI 0.75⁻0.91), adjusted SIR was 1.14 (CI 1.03⁻1.25). For larynx cancer, results in the opposite direction were seen: unadjusted SIR for economically inactive was 1.38 (CI 1.31⁻1.46) while the adjusted SIR was 0.91 (CI 0.86⁻0.96). Conclusions: Adjustment for the latent indicators of alcohol and tobacco consumption changed risk estimates for several occupations, gave a less confounded description of risk, and may guide in the identification of true risk factors.