Physical activity during adolescence and risk of colorectal adenoma later in life: results from the Nurses' Health Study II

Does Chinese herbal medicine (CHM) reduce colorectal adenoma (CRA) recurrence: protocol of a registry-based, cohort study and a qualitative interview

INTRODUCTION

Colorectal adenoma (CRA) is a precancerous lesion for colorectal cancer. Endoscopic resection is the first-line treatment for CRA. However, CRA recurrence rate is high. This proposed study aims to determine if Chinese herbal medicine (CHM) reduces CRA recurrence.

METHODS AND ANALYSIS

This project encompasses an observational, registry-based, cohort study and a nested qualitative study. The cohort study aims to include 364 postpolypectomy CRA participants at Guangdong Provincial Hospital of Chinese Medicine (GPHCM), China, with a follow-up phase of up to 1 year. In addition to routine care, these participants will receive a CHM treatment prescribed by experienced Chinese medicine (CM) clinicians. The CHM treatment encompasses CHM products and CHM formulae according to CM syndromes. The primary outcome is CRA recurrence rate at 1 year after enrolment. Secondary outcomes include characteristics of recurrent CRA, incidence of colorectal polyp (except for CRA), incidence of advanced CRA, incidence of colorectal cancer, improvement of gastrointestinal symptoms commonly seen in CRA patients, faecal occult blood test result, lipid level, fasting plasma glucose level, uric acid level, carcinoembryonic antigen, carbohydrate antigen 19-9, quality of life and safety evaluations. Logistic regression analysis will be used to explore the correlation between exposure and outcome. Qualitative interviews will be conducted among approximate 30 CRA patients from the cohort study and 10 CM practitioners in Department of Gastroenterology at GPHCM. Thematic analysis will be used to analyse qualitative data.

ETHICS AND DISSEMINATION

Ethical approval has been obtained from the Human Research Ethics Committee (HREC) of GPHCM (YF2022-320-02) and registered at Royal Melbourne Institute of Technology (RMIT) HREC. The results will be disseminated in peer-reviewed journals and international academic conferences.

TRIAL REGISTRATION NUMBER

ChiCTR2200065713.

Association between regular physical activity and lower incidence of colorectal cancer in patients with diabetes mellitus: a nationwide cohort study

AIM

The aim of this work was to investigate the association between changes in physical activity (PA) status and the development of colorectal cancer (CRC) in patients with diabetes.

METHOD

This nationwide population study included 1 439 152 patients with diabetes who underwent a health screening provided by the Korean National Health Insurance Service between January 2009 and December 2012 and a follow-up screening after 2 years. Based on changes in PA status, participants were categorized into four groups: remained inactive, remained active, active-to-inactive and inactive-to-active.

RESULTS

During the median follow-up period of 5.2 years, 38 244 new cases of CRC were diagnosed. Compared with the remained inactive group, among the three other groups, the remained active group had the lowest risk of CRC [adjusted hazard ratio (aHR) 0.93; 95% CI 0.90-0.96], followed by the inactive-to-active group (aHR 0.97; 95% CI 0.94-1.00) and active-to-inactive group (aHR 0.99; 95% CI 0.96-1.02), after adjusting for confounding variables (p = 0.0007). This reduction in cancer incidence in the remained active group was observed for both rectal cancer (aHR 0.87, 95% CI 0.79-0.95) and colon cancer (aHR 0.93, 95% CI 0.90-0.97), irrespective of sex. In terms of the intensity and amount of PA, moderate intensity PA was the most effective, and a positive correlation was found between the amount of PA and the reduction in CRC incidence.

CONCLUSION

Regular PA was independently associated with a decreased risk of CRC in patients with diabetes. The intensity and amount of physical activity both play a role in reducing the risk.

The association between multiple cardiovascular risk factors and overweight in Brazilian adolescents: an analysis based on the grade of membership

The aim of the current research is to analyze the coexistence of modifiable risk behaviors for cardiovascular disease (CVD) in 12-to-17-year-old adolescents living in Brazil and their influence on overweight. National, cross-sectional, school-based epidemiological study focused on estimating the prevalence of cardiovascular risk factors and metabolic syndrome in 12 to 17 year old adolescents enrolled in public and private schools in Brazilian counties accounting for more than 100 thousand inhabitants. The grade of membership method was used to identify the coexistence of risk factors among adolescents. The analytical sample comprised 71,552 adolescents. According to the two herein generated profiles, adolescents classified under Profile 2 have shown behaviors such as smoking, alcohol consumption and diet rich in Ultra-processed food intake ≥ 80% of the percentage of total caloric value. In addition, adolescents presenting CVD risk profile have shown increased likelihood of being overweight. The study has found coexistence of risk factors for CVD in Brazilian adolescents, with emphasis on tobacco smoking and alcoholic beverage intake. In addition, it heads towards the analysis of the association between CVD risk factors and health outcomes, such as overweight.

Adherence to the World Cancer Research Fund/American Institute for Cancer Research cancer prevention recommendations throughout the life course and risk of colorectal cancer precursors

BACKGROUND

Despite the increasing incidence in colorectal cancer (CRC) among the young population, the involvement of modifiable early-life exposures is understudied.

METHODS

We prospectively investigated the association of lifestyle score, which measures adherence to the 2018 World Cancer Research Fund/American Institute for Cancer Research (WCRF/AICR) cancer prevention recommendations, in adolescence and adulthood with risk of CRC precursors in 34,509 women enrolled in the Nurses' Health Study II. Participants reported adolescent diet in 1998 and subsequently underwent at least one lower gastrointestinal endoscopy between 1999 and 2015. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using multivariable logistic regression for clustered data.

RESULTS

During follow-up (1998-2015), 3036 women had at least one adenoma, and 2660 had at least one serrated lesion. In multivariable analysis, per unit increase in adolescent WCRF/AICR lifestyle score was not associated with risk of total adenoma or serrated lesions, in contrast to adult WCRF/AICR lifestyle score (OR = 0.92, 95% CI: 0.87-0.97, Ptrend = 0.002 for total adenoma; and OR = 0.86, 95% CI: 0.81-0.92, Ptrend < 0.001 for total serrated lesions).

CONCLUSION

Adherence to the 2018 WCRF/AICR recommendations during adulthood but not during adolescence was associated with a lower risk of CRC precursors.

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.

Active exercise after polypectomy reduces the risk of metachronous advanced colorectal neoplasm

BACKGROUND AND STUDY AIMS

Exercise is associated with a lower risk of colorectal neoplasm but its association with metachronous advanced colorectal neoplasm development after polypectomy remains unclear. We aimed to investigate associations between subjects' exercise habits and the risk of metachronous advanced colorectal neoplasm.

PATIENTS AND METHODS

This study analyzed subjects older than 40 years who received screening colonoscopy with polypectomy and surveillance colonoscopy between January 2009 and December 2016. All participants completed a standard questionnaire containing exercise habits before surveillance colonoscopy. Subjects' exercise habits were quantified as weekly exercise amounts (metabolic equivalents of task-day/week) and dichotomized (active/sedentary exercise habit) using averages as the cut-off point. The associations between incidence of metachronous advanced colorectal neoplasm and exercise habits were evaluated using Kaplan-Meier analysis and Cox regression models.

RESULTS

A total of 1820 subjects comprised the study cohort and 86 (4.73%) of them developed metachronous advanced colorectal neoplasm during the surveillance period. An active exercise habit after polypectomy was associated with a lower risk of metachronous advanced colorectal neoplasm (adjusted hazard ratio [aHR] 0.57, 95% confidence interval [CI] 0.35-0.91). Furthermore, this protective effect from exercise was specific for subjects having advanced neoplasm at screening colonoscopy (aHR 0.32, 95% CI 0.11-0.94).

CONCLUSIONS

An active exercise habit after polypectomy, a surrogate for a more active lifestyle, is associated with a lower risk for developing metachronous advanced colorectal neoplasm. A positive lifestyle modification, such as maintaining/establishing an active exercise habit, should be advised after polypectomy, especially for those with advanced colorectal neoplasm during screening.

Molecular Biologic and Epidemiologic Insights for Preventability of Colorectal Cancer

The etiology of colorectal cancer (CRC) has been informed from both a molecular biology perspective, which concerns the study of the nature, timing, and consequences of mutations in driver genes, and epidemiology, which focuses on identifying risk factors for cancer. For the most part, these fields have developed independently, and it is thus important to consider them in a more integrated manner. The molecular mutational perspective has stressed the importance of mutations due to replication of adult stem cells, and the molecular fingerprint of most CRCs does not suggest the importance of direct carcinogens. Epidemiology has identified numerous modifiable risk factors that account for most CRCs, most of which are not direct mutagens. The distribution of CRCs across the large bowel is not uniform, which is possibly caused by regional differences in the microbiota. Some risk factors are likely to act through or interact with the microbiota. The mutational perspective informs when risk factors may begin to operate in life and when they may cease to operate. Evidence from the mutational model and epidemiology supports that CRC risk factors begin early in life and may contribute to the risk of early-onset CRC. Later in carcinogenesis, there may be a "point of no return" when sufficient mutations have accumulated, and some risk factors do not affect cancer risk. This period may be at least 5-15 years for some risk factors. A more precise knowledge of timing of risk factor to cancer is required to inform preventive efforts.

Low-Intensity Exercise Modulates Gut Microbiota to Fight Against Radiation-Induced Gut Toxicity in Mouse Models

Radiation-induced gastrointestinal (GI) tract toxicity halts radiotherapy and degrades the prognosis of cancer patients. Physical activity defined as “any bodily movement produced by skeletal muscle that requires energy expenditure” is a beneficial lifestyle modification for health. Here, we investigate whether walking, a low-intensity form of exercise, could alleviate intestinal radiation injury. Short-term (15 days) walking protected against radiation-induced GI tract toxicity in both male and female mice, as judged by longer colons, denser intestinal villi, more goblet cells, and lower expression of inflammation-related genes in the small intestines. High-throughput sequencing and untargeted metabolomics analysis showed that walking restructured the gut microbiota configuration, such as elevated Akkermansia muciniphila, and reprogramed the gut metabolome of irradiated mice. Deletion of gut flora erased the radioprotection of walking, and the abdomen local irradiated recipients who received fecal microbiome from donors with walking treatment exhibited milder intestinal toxicity. Oral gavage of A. muciniphila mitigated the radiation-induced GI tract injury. Importantly, walking did not change the tumor growth after radiotherapy. Together, our findings provide novel insights into walking and underpin that walking is a safe and effective form to protect against GI syndrome of patients with radiotherapy without financial burden in a preclinical setting.

Simple Sugar and Sugar-Sweetened Beverage Intake During Adolescence and Risk of Colorectal Cancer Precursors

BACKGROUND & AIMS

Recent increasing trends in early-onset colorectal cancer (CRC) strongly supports that early-life diet is involved in CRC development. However, data are lacking on the relationship with high sugar intake during early life.

METHODS

We prospectively investigated the association of adolescent simple sugar (fructose, glucose, added sugar, total sugar) and sugar-sweetened beverage (SSB) intake with CRC precursor risk in 33,106 participants of the Nurses' Health Study II who provided adolescent dietary information in 1998 and subsequently underwent lower gastrointestinal endoscopy between 1999 and 2015. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using logistic regression for clustered data.

RESULTS

During follow-up, 2909 conventional adenomas (758 high-risk) and 2355 serrated lesions were identified (mean age at diagnoses, 52.2 ± 4.3 years). High sugar and SSB intake during adolescence was positively associated with risk of adenoma, but not serrated lesions. Per each increment of 5% of calories from total fructose intake, multivariable ORs were 1.17 (95% CI, 1.05-1.31) for total and 1.30 (95% CI, 1.06-1.60) for high-risk adenoma. By subsite, ORs were 1.12 (95% CI, 0.96-1.30) for proximal, 1.24 (95% CI, 1.05-1.47) for distal, and 1.43 (95% CI, 1.10-1.86) for rectal adenoma. Per 1 serving/day increment in SSB intake, ORs were 1.11 (95% CI, 1.02-1.20) for total and 1.30 (95% CI, 1.08-1.55) for rectal adenoma. Contrary to adolescent intake, sugar and SSB intake during adulthood was not associated with adenoma risk.

CONCLUSIONS

High intake of simple sugars and SSBs during adolescence was associated with increased risk of conventional adenoma, especially rectal adenoma.

Dairy intake during adolescence and risk of colorectal adenoma later in life

BACKGROUND

Higher dairy intake during adulthood has been associated with lower colorectal cancer risk. As colorectal carcinogenesis spans several decades, we hypothesised that higher dairy intake during adolescence is associated with lower risk of colorectal adenoma, a colorectal cancer precursor.

METHODS

In 27,196 females from the Nurses' Health Study 2, aged 25-42 years at recruitment (1989), who had completed a validated high school diet questionnaire in 1998 and undergone at least one lower bowel endoscopy between 1998 and 2011, logistic regression for clustered data was used to calculate odds ratios (ORs) and 95% confidence intervals (CI).

RESULTS

Colorectal adenomas were diagnosed in 2239 women. Dairy consumption during adolescence was not associated with colorectal adenoma risk (OR highest vs. lowest [≥4 vs. ≤1.42 servings/day] quintile [95% CI] 0.94 [0.80, 1.11]). By anatomical site, higher adolescent dairy intake was associated with lower rectal (0.63 [0.42, 0.95]), but not proximal (1.01 [0.80, 1.28]) or distal (0.97 [0.76, 1.24]) colon adenoma risk. An inverse association was observed with histologically advanced (0.72 [0.51, 1.00]) but not non-advanced (1.07 [0.86, 1.33]) adenoma.

CONCLUSIONS

In this large cohort of younger women, higher adolescent dairy intake was associated with lower rectal and advanced adenoma risk later in life.

NCCN Guidelines Insights: Colorectal Cancer Screening, Version 2.2020

The NCCN Guidelines for Colorectal Cancer (CRC) Screening describe various colorectal screening modalities as well as recommended screening schedules for patients at average or increased risk of developing sporadic CRC. They are intended to aid physicians with clinical decision-making regarding CRC screening for patients without defined genetic syndromes. These NCCN Guidelines Insights focus on select recent updates to the NCCN Guidelines, including a section on primary and secondary CRC prevention, and provide context for the panel's recommendations regarding the age to initiate screening in average risk individuals and follow-up for low-risk adenomas.

Physical activity patterns in a representative sample of adolescents from the largest city in Latin America: a cross-sectional study in Sao Paulo

OBJECTIVES

We examined the patterns of total and domain-specific physical activity (PA) by sex, socioeconomic status and maternal education level in adolescents from Sao Paulo city, Brazil.

DESIGN

Cross-sectional study.

PARTICIPANTS

We included a representative sample of 2682 (52.2% boys) adolescents aged 14-15 years from public and private schools in Sao Paulo, 2017. Socioeconomic status was assessed using a wealth index derived from principal component analysis. Descriptive analyses evaluated differences in total and domain-specific PA by sex, socioeconomic status and maternal education level.

OUTCOME MEASURES

We collected data on the frequency and duration that adolescents spent in each PA domain (active transportation, leisure PA and physical education classes) through a self-report questionnaire.

RESULTS

On average, adolescents spent 197.7 min/week (95% CI 190.6-204.8) in total PA. The proportion of adolescents achieving at least 60 min/day (≥420 min/week) was 12.7% (95% CI 11.4-14.1), with a higher prevalence in boys (18.3%) and in those with higher socioeconomic status (17.4%). Similar patterns were observed for leisure PA and physical education classes. Active transportation was higher in girls (46.0 min/week; 95% CI 42.6-49.6) than in boys (43.4 min/week, 95% CI 39.9-46.6). Boys and adolescents with higher socioeconomic status and higher maternal education level had higher levels of total PA.

CONCLUSIONS

We found a variation in patterns of total and domain-specific PA by sex, socioeconomic status and maternal education level in adolescents from Sao Paulo. Initiatives for promoting PA in adolescents should take these findings into account.

Body fatness over the life course and risk of serrated polyps and conventional adenomas

Serrated polyps (SPs) and conventional adenomas represent 2 distinct groups of colorectal premalignancy. The influence of early life adiposity on risk of these precursors remains unclear. Within the Nurses' Health Study, the Nurses' Health Study 2, and the Health Professionals Follow-up Study, we assessed body fatness during childhood using 9-level somatotype and obtained weight and body mass index (BMI) in adulthood. We used multivariable-adjusted logistic regression to examine the association of SPs and conventional adenomas with body fatness in early childhood (age 5), late childhood (age 10), early adulthood (age 18/21) and middle adulthood (baseline) and weight change during early-to-middle adulthood. During 18-20 years of follow-up, we documented 8,697 SPs and 10,219 conventional adenomas in 132,514 women; 2,403 SPs and 4,495 conventional adenomas in 29,207 men. We found a modest positive association of adiposity in early and late childhood with risk of SPs and conventional adenomas, with odds ratios ranging from 1.12 to 1.18 for comparison of extreme somatotypes groups. The associations were attenuated after adjusting for adulthood BMI but remained significant for conventional adenomas. No association with early life body fatness was found in men. Adulthood body fatness and weight change during early-to-middle adulthood showed positive relationships with SPs and conventional adenomas in both women and men, with stronger associations observed for SPs (p_{heterogeneity}  < 0.0001). Our findings indicated a potential role in development of colorectal cancer precursors of childhood body fatness in women, and early-to-middle adulthood weight gain and attained adiposity in both sexes.

Molecular Aspects of Colorectal Adenomas: The Interplay among Microenvironment, Oxidative Stress, and Predisposition

The development of colorectal cancer (CRC) is a multistep process initiated by a benign polyp that has the potential to evolve into in situ carcinoma through the interactions between environmental and genetic factors. CRC incidence rates are constantly increased for young adult patients presenting an advanced tumor stage. The majority of CRCs arise from colonic adenomas originating from aberrant cell proliferation of colon epithelium. Endoscopic polypectomy represents a tool for early detection and removal of polyps, although the occurrence of cancers after negative colonoscopy shows a significant incidence. It has long been recognized that the aberrant regulation of Wingless/It (Wnt)/β-Catenin signaling in the pathogenesis of colorectal cancer is supported by its critical role in the differentiation of stem cells in intestinal crypts and in the maintenance of intestinal homeostasis. For this review, we will focus on the development of adenomatous polyps through the interplay between renewal signaling in the colon epithelium and reactive oxygen species (ROS) production. The current knowledge of molecular pathology allows us to deepen the relationships between oxidative stress and other risk factors as lifestyle, microbiota, and predisposition. We underline that the chronic inflammation and ROS production in the colon epithelium can impair the Wnt/β-catenin and/or base excision repair (BER) pathways and predispose to polyp development. In fact, the coexistence of oxidative DNA damage and errors in DNA polymerase can foster C>T transitions in various types of cancer and adenomas, leading to a hypermutated phenotype of tumor cells. Moreover, the function of Adenomatous Polyposis Coli (APC) protein in regulating DNA repair is very important as therapeutic implication making DNA damaging chemotherapeutic agents more effective in CRC cells that tend to accumulate mutations. Additional studies will determine whether approaches based on Wnt inhibition would provide long-term therapeutic value in CRC, but it is clear that APC disruption plays a central role in driving and maintaining tumorigenesis.

Co-occurrence and clustering of the four major non-communicable disease risk factors in Brazilian adolescents: Analysis of a national school-based survey

Background

The major non-communicable chronic diseases (NCD) are associated with a small group of modifiable lifestyle-related risk factors, including smoking, insufficient physical activity, unhealthy eating, and alcohol abuse. In this study, we evaluated the co-occurrence and clustering of the major NCD risk factors among Brazilian adolescents.

Methods

This cross-sectional study analyzed data of 101,607 adolescents from the Brazilian National Survey of School Health (PeNSE) 2015. The risk factors included were: regular consumption of ultra-processed foods, irregular consumption of fruits and vegetables, insufficient physical activity, smoking, and alcohol consumption. Clustering was defined through the ratio between observed and expected prevalences of combination of risk factors greater than 1. Expected prevalence of the co-occurrence of risk factors was calculated from the joint probability of the behaviors. Additionally, we examined the presence of at least four risk factors according to socioeconomic characteristics.

Results

Of the 32 combinations of risk factors, 13 corresponded to clustering. We observed a strong correlation between alcohol consumption and smoking, which were found together in 8 of the 13 clusters identified. The most frequent combinations of risk factors involved unhealthy eating and insufficient physical activity. Only 2.9% of the adolescents did not present any risk behaviors, while 38.0%, 32.9%, 9.4% and 1.8% accumulated two, three, four and five risk factors, respectively. The accumulation of risk factors was higher in girls, older adolescents, those who did not live with both parents, children of less-educated mothers, students attending public school, and residents of cities in more developed urban areas of the country.

Conclusions

The main risk factors for NCD are frequent and not randomly distributed among Brazilian adolescents. Our results provide information for policymakers to target specific groups and joint behavioral risk factors for health improvement in adolescents.