Mucositis and muscle wasting are two common toxicity effects of cancer treatment in head and neck cancer (HNC). There is limited data evaluating cancer treatment toxicities in relation to vitamin status. This study aimed to assess changes in vitamin status during HNC treatment in relation to body composition, inflammation and mucositis. In this prospective cohort study, dietary intakes (3-day food record), plasma levels of vitamins and C-reactive protein (CRP) were assessed at baseline (at diagnosis) and post-treatment (after 6–8 weeks of radiation therapy with or without chemotherapy). Computed tomography images were used to quantify body composition. Mucositis information was collected from health records of patients. Twenty-eight HNC patients (age 60 ± 10 years) completed both study time points. Patients who developed mucositis had significantly lower dietary intake of vitamins and plasma 25-hydroxy vitamin D (25-OHD) and all-trans retinol levels (p < 0.02). Patients lost a considerable amount of muscle mass (3.4 kg) and fat mass (3.6 kg) over the course of treatment. There was a trend toward greater muscle loss in patients with 25-OHD < 50 nmol/L compared to patients with 25-OHD ≥ 50 nmol/L (p = 0.07). A significant negative correlation was found between plasma all-trans retinol and CRP level at the end of treatment (p = 0.03). Poor vitamin status could be a contributing factor in developing treatment-induced toxicities.

Socioeconomic inequities in diet quality are stable or widening in the United States; however, these trends have not been well characterized in other nations. Moreover, purpose-developed indices of inequities that can provide a more comprehensive and precise perspective of trends in absolute and relative dietary gaps and gradients using multiple indicators of socioeconomic position (SEP) have not yet been used, and can inform strategies to narrow dietary inequities. We quantified nationally representative trends in absolute and relative gaps and gradients in diet quality between 2004 and 2015 according to 3 indicators of SEP among adults in Canada. Adults (≥18 y old) who participated in the nationally representative, cross-sectional Canadian Community Health Survey—Nutrition in 2004 (n = 20,880) or 2015 (n = 13,970) were included. SEP was classified using household income (quintiles), education (5 categories), and neighborhood deprivation (quintiles). Dietary intake data from 24-h recalls were used to derive Healthy Eating Index-2015 (HEI-2015) scores. Dietary inequities were quantified using absolute and relative gaps (between the most and least disadvantaged) and absolute [Slope Index of Inequality (SII)] and relative gradients (Relative Index of Inequality). Overall and sex-stratified multivariable linear regression and generalized linear models examined trends in HEI-2015 scores between 2004 and 2015. Mean HEI-2015 scores improved from 55.3 to 59.0 (maximum: 100); however, these trends were not consistently equitable. Whereas inequities in HEI-2015 scores were stable in the total population and in females, the absolute gap [from 1.60 (95% CI: 0.09, 3.10) to 4.27 (95% CI: 2.20, 6.34)] and gradient [from SII = 2.09 (95% CI: 0.45, 3.73) to SII = 4.84 (95% CI: 2.49, 7.20)] in HEI-2015 scores for household income, and the absolute gradient for education [from SII = 8.06 (95% CI: 6.41, 9.71) to SII = 10.52 (95% CI: 8.73, 12.31)], increased in males. Absolute and relative gaps and gradients in overall diet quality remained stable or widened between 2004 and 2015 among adults in Canada.

Compared with those with a higher socio-economic position (SEP), individuals with a lower SEP have higher cancer morbidity and mortality. However, the contribution of modifiable risk factors to these inequities is not known. This study aimed to quantify the mediating effects of modifiable risk factors to associations between SEP and cancer morbidity and mortality. This study used a prospective observational cohort design. We combined eight cycles of the Canadian Community Health Survey (2000/2001–2011) as baseline data to identify a cohort of adults (≥35 years) without cancer at the time of survey administration (n = 309 800). The cohort was linked to the Discharge Abstract Database and the Canadian Mortality Database for cancer morbidity and mortality ascertainment. Individuals were followed from the date they completed the Canadian Community Health Survey until 31 March 2013. Dates of individual first hospitalizations for cancer and deaths due to cancer were captured during this time period. SEP was operationalized using a latent variable combining measures of education and household income. Self-reported modifiable risk factors, including smoking, excess alcohol consumption, low fruit-and-vegetable intake, physical inactivity and obesity, were considered as potential mediators. Generalized structural equation modelling was used to estimate the mediating effects of modifiable risk factors in associations between low SEP and cancer morbidity and mortality in the total population and stratified by sex. Modifiable risk factors together explained 45.6% of associations between low SEP and overall cancer morbidity and mortality. Smoking was the most important mediator in the total population and for males, accounting for 15.5% and 40.2% of the total effect, respectively. For females, obesity was the most important mediator. Modifiable risk factors are important mediators of socio-economic inequities in cancer morbidity and mortality. Nevertheless, more than half of the variance in these associations remained unexplained. Midstream interventions that target modifiable risk factors may help to alleviate inequities in cancer risk in the short term. However, ultimately, upstream interventions that target structural determinants of health are needed to reduce overall socio-economic inequities in cancer morbidity and mortality.

The relationship between dietary intake and body composition changes during cancer treatment has not been well characterized. The aim of this study was to compare dietary intake at diagnosis and end of treatment in relation to changes in muscle mass and adiposity in head and neck cancer (HNC) patients. Dietary intakes (three-day food record) and body composition using computed tomography (CT) were assessed at diagnosis (baseline) and after treatment completion (post-treatment). Skeletal muscle (SM) loss was explored as a consequence of energy and protein intake in relation to the minimum and maximum European Society of Parenteral and Enteral Nutrition (ESPEN) guidelines. Higher energy intakes (kcal/kg/day) and increases in energy intake (%) from baseline to post-treatment were correlated with attenuated muscle loss (r = 0.62, p < 0.01; r = 0.47, p = 0.04, respectively). Post-treatment protein intake demonstrated a weak positive correlation (r = 0.44, p = 0.05) with muscle loss, which did not persist when controlling for covariates. Meeting minimum ESPEN energy guidelines (25 kcal/kg/day) did not attenuate SM loss, whereas intakes >30 kcal/kg/day resulted in fewer participants losing muscle. Greater baseline adiposity correlated with greater SM loss (p < 0.001). Energy intakes of 30 kcal/kg/day may be required to protect against SM loss during treatment in HNC patients. The influence of adiposity on SM loss requires further exploration.

Dietary inequities in childhood may shape dietary and health inequities across the life course. Quantifying the magnitude and direction of trends in absolute and relative gaps and gradients in diet quality according to multiple indicators of socioeconomic position (SEP) can inform strategies to narrow these inequities. We examined trends in absolute and relative gaps and gradients in diet quality between 2004 and 2015 according to 3 indicators of SEP among a nationally representative sample of children in Canada. Data from children (aged 2–17 y; n = 18,670) who participated in the cross-sectional Canadian Community Health Survey–Nutrition in 2004 or 2015 were analyzed. SEP was based on total household income, household educational attainment, and neighborhood deprivation. Dietary intake data from 1 interviewer-administered 24-h dietary recall were used to derive a Healthy Eating Index–2015 (HEI-2015) score for each participant as a measure of diet quality. Inequities in diet quality were quantified using 4 indices: absolute and relative gaps (between highest and lowest SEP) and absolute (Slope Index of Inequality) and relative gradients (Relative Index of Inequality). Overall and age-stratified multivariable linear regression and generalized linear models examined trends in HEI-2015 scores between 2004 and 2015. Although mean HEI-2015 total scores improved from 52.3 to 57.3 (maximum 100 points; P < 0.001), absolute and relative gaps and gradients in diet quality remained mostly stable for all 3 SEP indicators. However, among children aged 6–11 y, absolute and relative gradients in diet quality according to household educational attainment and neighborhood deprivation widened. The diet quality of children in Canada was poor and inequitably patterned in 2004 and 2015. Although mean diet quality improved between 2004 and 2015, absolute and relative gaps and gradients in diet quality persisted, with some evidence of widening absolute and relative gradients among 6- to 11-y-olds.

Purpose: The Alberta’s Tomorrow Project (ATP) prospective cohort study was established in 2000 to investigate the causes of cancer and chronic disease. The cohort consists of almost 55 000 participants aged 35–69 years at the time of recruitment. From 2020 to 2022, ATP conducted a longitudinal substudy, the COVID-19 Antibody Testing (CAT) study, nested in this existing cohort, to understand the spread and impact of the SARS-CoV-2. In this cohort profile, we describe the CAT study design, recruitment and initial findings. Participants: In this prospective cohort substudy, ~4000 participants completed online surveys and provided blood samples at a study centre every 4 months for 1 year, across four cities in Alberta, Canada. The study was launched on a rolling basis beginning in September 2020 and data collection was completed in May 2022. The surveys collected information on health and lifestyle factors, COVID-19 (testing, symptoms, vaccination, public health recommendations) and impacts of the pandemic (including economic, health services, mental health). Blood samples were tested for antinucleocapsid and antispike protein SARS-CoV-2 antibodies. Findings to date: A total of 4102 participants consented and attended a study centre at baseline, and almost 90% of these completed the study. Overall, participants were aged 61±10 years, 60% female, 12% came from rural areas, 45% had at least a bachelor’s degree, 24% reported a household income <$C75 000 and 39% were retired. About 15% of participants tested positive for antibodies induced by a SARS-CoV-2 infection over the course of the study, and about 18% of those who were infected reported long COVID (persistent symptoms for >4 weeks). By the end of the study, 96% of participants had received at least one COVID-19 vaccine dose. Through investigating other outcomes, it was observed that participants under 50 years of age were more likely to be assessed to have mild or moderate-to-severe anxiety and depressive symptoms compared with older participants. In addition, approximately 15% of participants reported a moderate to major impact on their ability to meet financial obligations. Future plans: Serology results, together with health, lifestyle and sociodemographic data, and the continued follow-up of these participants as part of the broader ATP cohort study (planned through 2065), will provide opportunities to investigate the long-term sequelae of COVID-19 infection as well as the broader impacts of the pandemic on physical, mental and emotional health. Data are available to researchers on request through the ATP access process.