Characteristics of nonparticipants in a randomised colorectal cancer screening trial comparing sigmoidoscopy and faecal immunochemical testing.

Public health systems should guarantee universal access to health care services, including cancer screening. We assessed whether certain population subgroups were underrepresented among participants in colorectal cancer screening with sigmoidoscopy and faecal immunochemical testing (FIT). Between 2012 and 2019, about 140 000 individuals aged 50 to 74 years were randomly invited to once-only sigmoidoscopy or first round of FIT screening. Our study included 46 919 individuals invited to sigmoidoscopy and 70 019 to FIT between 2012 and 2017. We used logistic regression models to evaluate if demographic and socioeconomic factors and use of certain drugs were associated with participation. Twenty-four thousand one hundred and fifty-nine (51.5%) individuals attended sigmoidoscopy and 40 931 (58.5%) FIT screening. Male gender, young age, low education and income, being retired or unemployed, living alone, being an immigrant, long driving time to screening centre, and use of antidiabetic and psychotropic drugs were associated with low participation in both screening groups. Many of these factors also predicted low acceptance of colonoscopy after positive FIT. While male gender, young age and living alone were more strongly associated with nonparticipation in FIT than sigmoidoscopy, low education and income, being retired or immigrant and long driving time were more strongly associated with nonparticipation in sigmoidoscopy than FIT. In conclusion, participation was lower in sigmoidoscopy than FIT. Predictors of nonparticipation were similar between arms. However, low socioeconomic status, being an immigrant and long driving time affected participation more in sigmoidoscopy screening, suggesting that FIT may guarantee more equal access to screening services than sigmoidoscopy.

Associations between body shape across the life course and adulthood concentrations of sex hormones in men and pre- and postmenopausal women: a multicohort study.

The objective was to investigate associations between life-course adiposity and sex hormone concentrations: trajectory of adiposity from age 5 to 40 (premenopausal)/60 (postmenopausal women and men) in relation to levels of oestrone (E1), oestradiol (E2), sex hormone-binding globulins (SHBG), testosterone in 4801 premenopausal and 6019 postmenopausal women in the Nurses' Health Study (NHS) and NHS II, and 2431 men in the Health Professionals Follow-up Study. We used group-based trajectory models to identify groups within each cohort based on recalled somatotypes and reported BMI. Multivariate linear regression models were used to compare sex hormone concentration across different trajectory groups. The mean age at blood draw was 64·1 ± 8·1 years for men, 59·4 ± 6·0 for postmenopausal and 44·1 ± 4·6 for premenopausal women. In men, compared with the medium-stable group, lean-marked increase and medium increase groups had lower levels of SHBG (percentage difference: -17 and -9 %) and testosterone (-15 and -13 %). In postmenopausal women, compared with the medium-stable group, lean-marked increase and medium increase groups had higher levels of E1 (21 and 34 %) and E2 (45 and 68 %) but lower level of SHBG (-29 and -35 %). In premenopausal women, compared with the lean-moderate increase group, medium-stable/increase and heavy-stable/increase groups had lower levels of SHBG (-6 and -28 %). Attained adulthood adiposity and middle-life weight gain were associated with lower SHBG and testosterone in men, higher E1 and E2 and lower SHBG in postmenopausal women, and lower SHBG in premenopausal women. The study indicates the importance of maintaining a healthy body weight throughout life course for homoeostasis of sex hormones.

DNA base oxidation in relation to TNM stages and chemotherapy treatment in colorectal cancer patients 2-9 months post-surgery.

Accumulation of DNA damage is a critical feature of genomic instability, which is a hallmark of various cancers. The enzyme-modified comet assay is a recognized method to detect specific DNA lesions at the level of individual cells. In this cross-sectional investigation, we explore possible links between clinicopathological and treatment related factors, nutritional status, physical activity and function, and DNA damage in a cohort of colorectal cancer (CRC) patients with non-metastatic disease. Levels of DNA damage in peripheral mononuclear blood cells (PBMCs) assessed 2-9 months post-surgery, were compared across tumour stage (localized (stage I-II) vs. regional (stage III) disease), localization (colon vs. rectosigmoid/rectum cancer), and adjuvant chemotherapy usage, with the last dosage administrated 2-191 days prior to sampling. Associations between DNA damage and indicators of nutritional status, physical activity and function were also explored. In PBMCs, DNA base oxidation was higher in patients diagnosed with regional compared with localized tumours (P = 0.03), but no difference was seen for DNA strand breaks (P > 0.05). Number of days since last chemotherapy dosage was negatively associated with DNA base oxidation (P < 0.01), and patients recently receiving chemotherapy (<15 days before blood collection) had higher levels of DNA base oxidation than those not receiving chemotherapy (P = 0.03). In the chemotherapy group, higher fat mass (in kg and %) as well as lower physical activity were associated with greater DNA base oxidation (P < 0.05). In conclusion, DNA base oxidation measured with the enzyme-modified comet assay varies according to tumour and lifestyle related factors in CRC patients treated for non-metastatic disease.

Exploring the gut DNA virome in fecal immunochemical test stool samples reveals associations with lifestyle in a large population-based study.

Stool samples for fecal immunochemical tests (FIT) are collected in large numbers worldwide as part of colorectal cancer screening programs. Employing FIT samples from 1034 CRCbiome participants, recruited from a Norwegian colorectal cancer screening study, we identify, annotate and characterize more than 18000 DNA viruses, using shotgun metagenome sequencing. Only six percent of them are assigned to a known taxonomic family, with Microviridae being the most prevalent viral family. Linking individual profiles to comprehensive lifestyle and demographic data shows 17/25 of the variables to be associated with the gut virome. Physical activity, smoking, and dietary fiber consumption exhibit strong and consistent associations with both diversity and relative abundance of individual viruses, as well as with enrichment for auxiliary metabolic genes. We demonstrate the suitability of FIT samples for virome analysis, opening an opportunity for large-scale studies of this enigmatic part of the gut microbiome. The diverse viral populations and their connections to the individual lifestyle uncovered herein paves the way for further exploration of the role of the gut virome in health and disease.

Attenuation of DNA base oxidation in post-surgery colorectal stage III patients at subsequent follow-ups.

DNA damage caused by oxidative reactions plays a crucial role in the pathogenesis of colorectal cancer (CRC). In a previous cross-sectional study, CRC patients diagnosed with regional disease (stage III) exhibited a higher level of DNA base oxidation in peripheral blood mononuclear cells (PBMCs) 2-9 months post-surgery compared to those with localized disease (stage I-II). To further explore this observation over time, the present study aimed to investigate DNA base oxidation in CRC patients with localized versus regional disease 6 and 12 months after the initial measurements. The present study included patients enrolled in the randomized controlled trial Norwegian Dietary Guidelines and Colorectal Cancer Survival (CRC-NORDIET). The standard comet assay, modified with the lesion-specific enzyme formamidopyrimidine DNA glycosylase (Fpg), was applied to measure DNA base oxidation in PBMCs at the 6- and 12-month follow-ups. Of the 255 patients assessed at baseline, 156 were included at the 6-month follow-up, with 89 of these patients included in the 12-month follow-up. In contrast to our observation at baseline, there were no significant differences in the levels of DNA base oxidation between patients diagnosed with localized disease and those with regional involvement at the 6- and 12-month follow-up visits (P = 0.81 and P = 0.09, respectively). Patients with stage III disease exhibited a significant decrease in the levels of DNA base oxidation from baseline to 6 months (P < 0.01) and baseline to 12 months (P = 0.03), but no significant difference from 6 to 12 months (P = 0.80). In conclusion, the initially elevated levels of DNA base oxidation in PBMCs, observed 2-9 months post-surgery in patients diagnosed with regional disease (stage III), subsequently decreased to levels comparable to patients with localized disease (stage I-II) at the 6- and 12-month follow-ups.

Effect of a personalized intensive dietary intervention on base excision repair (BER) in colorectal cancer patients: Results from a randomized controlled trial.

DNA repair is essential to maintain genomic integrity and may affect colorectal cancer (CRC) patients' risk of secondary cancers, treatment efficiency, and susceptibility to various comorbidities. Bioactive compounds identified in plant foods have the potential to modulate DNA repair mechanisms, but there is limited evidence of how dietary factors may affect DNA repair activity in CRC patients in remission after surgery. The aim of this study was to investigate the effect of a 6-month personalized intensive dietary intervention on DNA repair activity in post-surgery CRC patients (stage I-III). The present study included patients from the randomized controlled trial CRC-NORDIET, enrolled 2-9 months after surgery. The intervention group received an intensive dietary intervention emphasizing a prudent diet with specific plant-based foods suggested to dampen inflammation and oxidative stress, while the control group received only standard care advice. The comet-based in vitro repair assay was applied to assess DNA repair activity, specifically base excision repair (BER), in peripheral blood mononuclear cells (PBMCs). Statistical analyses were conducted using gamma generalized linear mixed models (Gamma GLMM). A total of 138 CRC patients were included, 72 from the intervention group and 66 from the control group. The BER activity in the intervention group did not change significantly compared to the control group. Our findings revealed a substantial range in both inter- and intra-individual levels of BER. In conclusion, the results do not support an effect of dietary intervention on BER activity in post-surgery CRC patients during a 6-month intervention period.

Elucidating Under-Studied Aspects of the Link Between Obesity and Multiple Myeloma: Weight Pattern, Body Shape Trajectory, and Body Fat Distribution.

BACKGROUND: Although obesity is an established modifiable risk factor for multiple myeloma (MM), several nuanced aspects of its relation to MM remain unelucidated, limiting public health and prevention messages. METHODS: We analyzed prospective data from the Nurses' Health Study and Health Professionals Follow-Up Study to examine MM risk associated with 20-year weight patterns in adulthood, body shape trajectory from ages 5 to 60 years, and body fat distribution. For each aforementioned risk factor, we report hazard ratios (HRs) and 95% confidence intervals (CIs) for incident MM from multivariable Cox proportional-hazards models. RESULTS: We documented 582 incident MM cases during 4 280 712 person-years of follow-up. Persons who exhibited extreme weight cycling, for example, those with net weight gain and one or more episodes of intentional loss of at least 20 pounds or whose cumulative intentional weight loss exceeded net weight loss with at least one episode of intentional loss of 20 pounds or more had an increased MM risk compared with individuals who maintained their weight (HR = 1.71, 95% CI = 1.05 to 2.80); the association was statistically nonsignificant after adjustment for body mass index. We identified four body shape trajectories: lean-stable, lean-increase, medium-stable, and medium-increase. MM risk was higher in the medium-increase group than in the lean-stable group (HR = 1.62, 95% CI = 1.22 to 2.14). Additionally, MM risk increased with increasing hip circumference (HR per 1-inch increase: 1.03, 95% CI = 1.01 to 1.06) but was not associated with other body fat distribution measures. CONCLUSIONS: Maintaining a lean and stable weight throughout life may provide the strongest benefit in terms of MM prevention.

Trajectories of body fatness from age 5 to 60 y and plasma biomarker concentrations of the insulin-insulin-like growth factor system.

Background: A major pathway through which obesity increases the risk of cardiometabolic diseases and cancer is by inducing hormonal and metabolic abnormalities, including hyperinsulinemia and altered insulin-like growth factor (IGF) signaling. However, little is known about the influence of lifetime adiposity on the relevant biomarkers. Objective: The aim of this study was to examine associations of trajectories of body fatness with plasma biomarker concentrations of the insulin-IGF system in 2 large prospective cohorts of US men and women. Design: Associations between trajectories of body fatness and concentrations of plasma C-peptide, IGF-I, IGF-binding protein (IGFBP) 1, IGFBP-3, and the IGF-I-to-IGFBP-3 molar ratio was examined in 9386 women of the Nurses' Health Study and 3941 men of the Health Professionals Follow-Up Study. Group-based trajectory modeling was used to create trajectory groups on the basis of self-reported somatotype data at ages 5, 10, 20, 30, and 40 y and body mass index (BMI) at ages 45, 50, 55, and 60 y. We used multivariate linear regression models to examine the associations of trajectories with biomarker concentrations. Results: Five trajectories of body fatness were identified: "lean-stable," "lean-moderate increase," "lean-marked increase," "medium-stable/increase," and "medium-marked increase." Compared with the lean-stable group, the lean-marked increase and medium-marked increase groups had significantly higher concentrations of C-peptide (percentage difference-women: 44% and 73%; men: 27% and 51%) and lower concentrations of IGFBP-1 (women: -61% and -78%; men: -47% and -65%). Adjustment for current BMI attenuated the association to null for the medium-marked increase group, but the lean-marked increase group still had modestly higher concentrations of C-peptide (women: 10%; men: 6%) and lower concentrations of IGFBP-1 (women: -18%; men: -21%) than the lean-stable group. Conclusions: Adiposity across the life span was associated with higher C-peptide and lower IGFBP-1 concentrations in adulthood. The associations were largely driven by attained adiposity and, to a lesser extent, weight gain in early-middle adulthood. This trial was registered at www.clinicaltrials.gov as NCT03419455.