Exploring the Future of Cancer Impact in Alberta: Projections and Trends 2020-2040

The impact of cancer in Alberta is expected to grow considerably, largely driven by population growth and aging. The Future of Cancer Impact (FOCI) initiative offers an overview of the present state of cancer care in Alberta and highlights potential opportunities for research and innovation across the continuum. In this paper, we present a series of detailed projections and analyses regarding cancer epidemiological estimates in Alberta, Canada. Data on cancer incidence and mortality in Alberta (1998-2018) and limited-duration cancer prevalence in Alberta (2000-2019) were collected from the Alberta Cancer Registry. We used the Canproj package in the R software to project these epidemiological estimates up to the year 2040. To estimate the direct management costs, we ran a series of microsimulations using the OncoSim All Cancers Model. Our findings indicate that from 2020, the total number of annual new cancer cases and cancer-related deaths are projected to increase by 56% and 49% by 2040, respectively. From 2019, the five-year prevalence of all cancers in Alberta is projected to increase by 86% by 2040. In line with these trends, the overall direct cost of cancer management is estimated to increase by 53% in 2040. These estimates and projections are integral to future strategic planning and investment.

Health-Related and Psychosocial Factors Associated with Prostate Cancer Stage at Diagnosis among Males Participating in Alberta's Tomorrow Project

Prostate cancer (PCa) stage at diagnosis is an important predictor of cancer prognosis. In Canada, over one-quarter of males are diagnosed with advanced-stage PCa. Studies have identified several factors associated with PCa stage at diagnosis; however, evidence from Canada is limited. This study aimed to examine associations between sociodemographic characteristics, health history, health practices, and psychosocial factors and PCa stage at diagnosis among males participating in Alberta's Tomorrow Project (ATP), a prospective cohort in Alberta, Canada. The study included males aged 35-69 years who developed PCa until January 2018. Factors associated with PCa stage at diagnosis were examined using partial proportional odds (PPO) ordinal regression models. A total of 410 males were diagnosed with PCa over the study period. A higher number of lifetime prostate-specific antigen tests were associated with earlier-stage PCa (OR 0.91, p = 0.02, 95% CI 0.83-0.99), while higher abdominal circumference (OR 1.02, p = 0.05, 95% CI 1.00-1.03), lower social support (OR 2.34, p < 0.01, 95% CI 1.31-4.17), and having children (OR 2.67, p < 0.01, 95% CI 1.38-5.16) were associated with later-stage disease. This study identified factors previously found in the literature as well as novel factors associated with PCa stage at diagnosis, which can help inform targets for cancer prevention programs to improve PCa prognosis.

Development and External Validation of Partial Proportional Odds Risk Prediction Models for Cancer Stage at Diagnosis among Males and Females in Canada

Risk prediction models for cancer stage at diagnosis may identify individuals at higher risk of late-stage cancer diagnoses. Partial proportional odds risk prediction models for cancer stage at diagnosis for males and females were developed using data from Alberta's Tomorrow Project (ATP). Prediction models were validated on the British Columbia Generations Project (BCGP) cohort using discrimination and calibration measures. Among ATP males, older age at diagnosis was associated with an earlier stage at diagnosis, while full- or part-time employment, prostate-specific antigen testing, and former/current smoking were associated with a later stage at diagnosis. Among ATP females, mammogram and sigmoidoscopy or colonoscopy were associated with an earlier stage at diagnosis, while older age at diagnosis, number of pregnancies, and hysterectomy were associated with a later stage at diagnosis. On external validation, discrimination results were poor for both males and females while calibration results indicated that the models did not over- or under-fit to derivation data or over- or under-predict risk. Multiple factors associated with cancer stage at diagnosis were identified among ATP participants. While the prediction model calibration was acceptable, discrimination was poor when applied to BCGP data. Updating our models with additional predictors may help improve predictive performance.

Using care pathways for cancer diagnosis in primary care: a qualitative study to understand family physicians' mental models

BACKGROUND

Care pathways are tools that can help family physicians navigate the complexities of the cancer diagnostic process. Our objective was to examine the mental models associated with using care pathways for cancer diagnosis of a group of family physicians in Alberta.

METHODS

We conducted a qualitative study using cognitive task analysis, with interviews in the primary care setting between February and March 2021. Family physicians whose practices were not heavily oriented toward patients with cancer and who did not work closely with specialized cancer clinics were recruited with the support of the Alberta Medical Association and leveraging our familiarity with Alberta's Primary Care Networks. We conducted simulation exercise interviews with 3 pathway examples over Zoom, and we analyzed data using both macrocognition theory and thematic analysis.

RESULTS

Eight family physicians participated. Macrocognitive functions (and subthemes) related to mental models were sense-making and learning (confirmation and validation, guidance and support, and sense-giving to patients), care coordination and diagnostic decision-making (shared understanding). Themes related to the use of the pathways were limited use in diagnosis decisions, use in guiding and supporting referral, only relevant and easy-to-process information, and easily accessible.

INTERPRETATION

Our findings suggest the importance of designing pathways intentionally for streamlined integration into family physicians' practices, highlighting the need for co-design approaches. Pathways were identified as a tool that, used in combination with other tools, may help gather information and support cancer diagnosis decisions, with the goals of improving patient outcomes and care experience.

Applying suggested new terminology and definitions for human milk feeding in the Alberta Pregnancy Outcomes and Nutrition (APrON) longitudinal pregnancy cohort

The complexity of human milk-feeding behaviours may not be captured using simpler definitions of "exclusive" and "non-exclusive" breastfeeding. New definitions have been suggested to describe variation in these behaviours more fully but have not been widely applied. We applied the new definitions to data derived from 3-day human milk-feeding diaries. Participants (n = 1091) recorded the number, beginning/end time, and modes of feeding of infants aged 3 months. Data were used to create six exclusive groups according to feeding mode(s): (1) human milk at-breast only; (2) human milk at-breast and human milk in a bottle; (3) human milk at-breast and infant formula in a bottle; (4) human milk at-breast and human milk and infant formula mixed in the same bottle; (5) human milk at-breast, human milk in a bottle, and infant formula in a bottle (not mixed); and (6) a bottle that sometimes contained human milk and sometimes infant formula (not mixed), never at-breast. Differences in maternal and infant characteristics were examined among groups. Fifty-seven percent fed at-breast only (Group 1). Those in Group 1 spent a similar amount of time feeding directly at-breast (median 132 (IQR 98-172) min/day) as those in Groups 2 (124 (95-158)), 3 (143 (100-190)), and 5 (114 (84-142)) (p > 0.05), indicating that adding bottle feeding did not always reduce the time infants were fed at-breast. Applying new suggested definitions to describe human milk-feeding behaviours from the mothers' perspective highlights the complexity of patterns used and warrants further application and research to explore impacts on health outcomes.

Pre-diagnosis lifestyle, health history and psychosocial factors associated with stage at breast cancer diagnosis - Potential targets to shift stage earlier

BACKGROUND

Early detection of breast cancer improves survival, so identifying factors associated with stage at diagnosis may help formulate cancer prevention messages tailored for higher risk women. The goal of this study was to evaluate associations between multiple potential risk factors, including novel ones, measured before a breast cancer diagnosis and stage at diagnosis in women from Alberta, Canada.

METHODS

Women enrolled in Alberta's Tomorrow Project completed health and lifestyle questionnaires on average 7 years before their breast cancer diagnosis. The association of previously identified and novel predictors with stage (I, II and III + IV) at diagnosis were simultaneously evaluated in partial proportional odds ordinal (PPO) regression models.

RESULTS

The 492 women in this study were predominantly diagnosed in Stage 1 (51.4%), had college or university education (75.4%), were married or had a partner (74.6%), had been pregnant (90.2%), had taken birth control pills for any reason (86.8%), and had an average body mass index of 26.6. Most had at least one mammogram (83%) with five mammograms the average number. Nearly all reported previously having a breast health examination from a medical practitioner (92.5%). Statistically significant factors identified in the PPO model included protective ones (older age at diagnosis, high household income, parity, smoking, spending time in the sun during high ultraviolet times, having a mammogram and high daily protein intake) and ones that increased risk of later stage at diagnosis (a comorbidity, current stressful situations and high daily caloric intake).

CONCLUSION

Shifting breast cancer stage at diagnosis downwards may potentially be achieved through cancer prevention programs that target higher risk groups such as women with co-morbidities, non-smokers and younger women who may be eligible for breast cancer screening.

Health-Related and Behavioral Factors Associated With Lung Cancer Stage at Diagnosis: Observations From Alberta's Tomorrow Project

Background

Lung cancer is the leading cause of cancer death in Canada, with stage at diagnosis among the top predictors of lung cancer survival. Identifying factors associated with stage at diagnosis can help reduce lung cancer morbidity and mortality. This study used data from a prospective cohort study of adults living in Alberta, Canada to examine factors associated with lung cancer stage at diagnosis.

Methods

This cohort study used data from adults aged 35–69 years enrolled in Alberta’s Tomorrow Project. Partial Proportional Odds models were used to examine associations between sociodemographic characteristics and health-related factors and subsequent lung cancer stage at diagnosis.

Results

A total of 221 participants (88 males and 133 females) developed lung cancer over the study period. Nearly half (48.0%) of lung cancers were diagnosed at a late stage (stage IV), whereas 30.8 % and 21.3% were diagnosed at stage I/II and III, respectively. History of sunburn in the past year was protective against late-stage lung cancer diagnosis (odds ratio (OR) .40, P=.005). In males, a higher number of lifetime prostate specific antigen tests was associated with reduced odds of late-stage lung cancer diagnosis (odds ratio .66, P=.02). Total recreational physical activity was associated with increased odds of late-stage lung cancer diagnosis (OR 1.08, P=.01).

Discussion

Lung cancer stage at diagnosis remains a crucial determinant of prognosis. This study identified important factors associated with lung cancer stage at diagnosis. Study findings can inform targeted cancer prevention initiatives towards improving early detection of lung cancer and lung cancer survival.

Oncology Patients' Experiences With Novel Electronic Patient Portals to Support Care and Treatment: Qualitative Study With Early Users and Nonusers of Portals in Alberta, Canada

Background

With the current proliferation of clinical information technologies internationally, patient portals are increasingly being adopted in health care. Research, conducted mostly in the United States, shows that oncology patients have a keen interest in portals to gain access to and track comprehensive personal health information. In Canada, patient portals are relatively new and research into their use and effects is currently emerging. There is a need to understand oncology patients’ experiences of using eHealth tools and to ground these experiences in local sociopolitical contexts of technology implementation, while seeking to devise strategies to enhance portal benefits.

Objective

The purpose of this study was to explore the experiences of oncology patients and their family caregivers when using electronic patient portals to support their health care needs. We focused on how Alberta’s unique, 2-portal context shapes experiences of early portal adopters and nonadopters, in anticipation of a province-wide rollout of a clinical information system in oncology facilities.

Methods

This qualitative descriptive study employed individual semistructured interviews and demographic surveys with 11 participants. Interviews were audio-recorded and transcribed verbatim. Data were analyzed thematically. The study was approved by the University of Alberta Human Research Ethics Board.

Results

Participants currently living with nonactive cancer discussed an online patient portal as one among many tools (including the internet, phone, videoconferencing, print-out reports) available to make sense of their diagnosis and treatment, maintain connections with health care providers, and engage with information. In the Fall of 2020, most participants had access to 1 of 2 of Alberta’s patient portals and identified ways in which this portal was supportive (or not) of their ongoing health care needs. Four major themes, reflecting the participants’ broader concerns within which the portal use was occurring, were generated from the data: (1) experiencing doubt and the desire for transparency; (2) seeking to become an informed and active member of the health care team; (3) encountering complexity; and (4) emphasizing the importance of the patient–provider relationship.

Conclusions

Although people diagnosed with cancer and their family caregivers considered an online patient portal as beneficial, they identified several areas that limit how portals support their oncology care. Providers of health care portals are invited to recognize these limitations and work toward addressing them.

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.

Physician perspectives on delays in cancer diagnosis in Alberta: a qualitative study

BACKGROUND

Delays in cancer diagnosis have been associated with reduced survival, decreased quality of life after treatment, and suboptimal patient experience. The objective of the study was to explore the perspectives of a group of family physicians and other specialists regarding potentially avoidable delays in diagnosing cancer, and approaches that may help expedite the process.

METHODS

We conducted a qualitative study using interviews with physicians practising in primary and outpatient care settings in Alberta between July and September 2019. We recruited family physicians and specialists who were in a position to discuss delays in cancer diagnosis by email via the Cancer Strategic Clinical Network and the Alberta Medical Association. We conducted semistructured interviews over the phone, and analyzed data using thematic analysis.

RESULTS

Eleven family physicians and 22 other specialists (including 7 surgeons or surgical oncologists, 3 pathologists, 3 radiologists, 2 emergency physicians and 2 hematologists) participated in interviews; 22 were male (66.7%). We identified 4 main themes describing 9 factors contributing to potentially avoidable delays in diagnosis, namely the nature of primary care, initial presentation, investigation, and specialist advice and referral. We also identified 1 theme describing 3 suggestions for improvement, including system integration, standardized care pathways and a centralized advice, triage and referral support service for family physicians.

INTERPRETATION

These findings suggest the need for enhanced support for family physicians, and better integration of primary and specialty care before cancer diagnosis. A multifaceted and coordinated approach to streamlining cancer diagnosis is required, with the goals of enhancing patient outcomes, reducing physician frustration and optimizing efficiency.

Administering a combination of online dietary assessment tools, the Automated Self-Administered 24-Hour Dietary Assessment Tool, and Diet History Questionnaire II, in a cohort of adults in Alberta's Tomorrow Project

BACKGROUND

Evidence suggests that combining tools that gather short- and long-term dietary data may be the optimal approach for the assessment of diet-disease associations in epidemiologic studies. Online technology can reduce the associated burdens for researchers and participants, but feasibility must be demonstrated in real-world settings before wide-scale implementation.

OBJECTIVE

The objective of this study was to determine the feasibility and acceptability of combining web-based tools (the Automated Self-Administered 24-hour Dietary Assessment Tool [ASA24-2016] and the past-year Diet History Questionnaire II [DHQ-II]) in a subset of participants in Alberta's Tomorrow Project, a prospective cohort.

DESIGN

For this feasibility study, invitations were mailed to 550 randomly selected individuals enrolled in Alberta's Tomorrow Project. Consented participants (n = 331) were asked to complete a brief sociodemographic and health questionnaire, four ASA24-2016 recalls, the DHQ-II, and an evaluation survey.

PARTICIPANTS/SETTING

The study was conducted from March 2016 to December 2016 in Alberta, Canada. The majority of participants, mean age (SD) = 57.4 (9.8) years, were women (70.7%), urban residents (85.5%), and nonsmokers (95.7%).

MAIN OUTCOME MEASURES

Primary outcomes were number of ASA24-2016 recalls completed, response rate of DHQ-II completion, and time to complete each assessment.

STATISTICAL ANALYSES

The Wilcoxon signed rank sum test was used to assess differences in completion time.

RESULTS

One-third (n = 102) of consenting participants did not complete any ASA24-2016 recalls. The primary reason to withdraw from the feasibility study was a lack of time. Among consenting participants, 51.9% (n = 172), 41.1% (n = 136), and 36.5% (n = 121) completed at least two ASA24-2016 recalls, the DHQ-II, and at least two ASA24-2016 recalls plus the DHQ-II, respectively. Median (25th to 75th percentile) completion times for participants who completed all recalls were 39 minutes (25 to 53 minutes) for the first ASA24-2016 recall and 60 minutes (40 to 90 minutes) for the DHQ-II.

CONCLUSIONS

Findings indicate combining multiple ASA24-2016 recalls and the DHQ-II is feasible in this subset of Alberta's Tomorrow Project participants. However, optimal response rates may be contingent on providing participant support. Completion may also be sensitive to timing and frequency of recall administration.

Nutrition and neurodevelopment: the search for candidate nutrients in the Seychelles Child Development Nutrition Study

This review examines the role of nutrients in child development and outlines the key nutrients identified as potentially important to neurodevelopment among high fish consumers in the Seychelles Child Development Nutrition Study (SCDNS). It describes the clinical assessment of these nutrients in the blood and breast milk samples collected from the cohort of 300 pregnant women who were recruited, at their first antenatal visit, on the SCDNS. These key nutrients include the long chain polyunsaturated fatty acids (LCPUFA), docosohexaenoic acid (DHA) and arachidonic acid (AA), both of which may affect neurodevelopment in the later stages of fetal growth. Only DHA, however, is strongly associated with fish consumption, the predominant source of the neurotoxicant methyl mercury (MeHg). Any benefits of increased selenium status on neurodevelopment are likely to accrue via detoxification of MeHg during fetal growth, while benefits of optimal iodine or thyroid status are likely to be directly related to neurodevelopment during late fetal growth. Unlike LCPUFA, Se, and I, the status of the B vitamins, folate, vitamin B12, vitamin B6, and riboflavin are unlikely to be closely related to fish consumption but the status of each of these B vitamins is likely to impinge on overall status of choline, which is expected to have direct effects on neurodevelopment both prenatally and postnatally and may also impact on MeHg toxicity. Choline status, together with the status of two other candidate nutrients, zinc and copper, which are also likely to have effects on neurodevelopment prenatally and postnatally, are expected to have some correlation with fish consumption.

From symptom to cancer diagnosis: Perspectives of patients and family members in Alberta, Canada

BACKGROUND

Significant intervals from the identification of suspicious symptoms to a definitive diagnosis of cancer are common. Streamlining pathways to diagnosis may increase survival, quality of life post-treatment, and patient experience. Discussions of pathways to diagnosis from the perspective of patients and family members are crucial to advancing cancer diagnosis.

AIM

To examine the perspectives of a group of patients with cancer and family members in Alberta, Canada, on factors associated with timelines to diagnosis and overall experience.

METHODS

A qualitative approach was used. In-depth, semi-structured interviews with patients with cancer (n = 18) and patient relatives (n = 5) were conducted and subjected to a thematic analysis.

FINDINGS

Participants struggled emotionally in the diagnostic period. Relevant to their experience were: potentially avoidable delays, concerns about health status, and misunderstood investigation process. Participants emphasized the importance of their active involvement in the care process, and had unmet supportive care needs.

CONCLUSION

Psychosocial supports available to potential cancer patients and their families are minimal, and may be important for improved experiences before diagnosis. Access to other patients' lived experiences with the diagnostic process and with cancer, and an enhanced supportive role of family doctors might help improve experiences for patients and families in the interval before receiving a diagnosis of cancer, which may have a significant impact on wellbeing.

High-sensitivity C-reactive protein, hemoglobin A1c and breast cancer risk: a nested case-control study from Alberta's Tomorrow Project cohort

PURPOSE

Our aim is to examine the associations between high-sensitivity C-reactive protein (hsCRP) and hemoglobin A1c (HbA1c), common biomarkers of inflammation and insulin resistance, respectively, with breast cancer risk, while adjusting for measures of excess body size.

METHODS

We conducted a nested case-control study within the Alberta's Tomorrow Project cohort (Alberta, Canada) including 197 incident breast cancer cases and 394 matched controls. The sample population included both pre- and postmenopausal women. Serum concentrations of hsCRP and HbA1c were measured from blood samples collected at baseline, along with anthropometric measurements, general health and lifestyle data. Conditional logistic regression was used to evaluate associations between hsCRP, HbA1c, and breast cancer risk adjusted for excess body size (body fat percentage) and other risk factors for breast cancer.

RESULTS

Higher concentrations of hsCRP were associated with elevated breast cancer risk (odds ratio [OR] 1.27; 95% confidence interval [95% CI] 1.03-1.55). The observed associations were unchanged with adjustment for body fat percentage. Higher HbA1c concentrations were not significantly associated with an increased breast cancer risk (OR 1.22; 95% CI 0.17-8.75).

CONCLUSION

These data suggest that hsCRP may be associated with elevated breast cancer risk, independent of excess body size. However, elevated concentrations of HbA1c did not appear to increase breast cancer risk in apparently healthy women.

Associations of appetite sensations and metabolic characteristics with weight retention in postpartum women

Postpartum weight retention (PPWR) is an important risk factor for long-term obesity. Appetite may be a key factor regulating PPWR. The objectives of this study were to determine the associations between (i) PPWR and appetite; and (ii) appetite, lactation, and metabolic characteristics. Data from 49 women at 9 months postpartum contributed to this cross-sectional analysis. Energy expenditure was assessed in a whole-body calorimetry unit for 24 h. Appetite sensations were rated using visual analogue scales. Lactation (min/day) was measured using a 3-day breastfeeding diary. PPWR was negatively associated with fullness (β ± SE; R² = -2.97 ± 0.72; 0.661; P < 0.001), and satiety (-2.75 ± 0.81; 0.617; P = 0.002), and was positively associated with hunger (2.19 ± 1.02; 0.548; P = 0.039), prospective food consumption (PFC; 2.19 ± 0.91; 0.562; P = 0.021), and composite appetite score (CAS; 0.34 ± 0.09; 0.632; P = 0.001). Lactation was associated with higher CAS (39.68 ± 15.56; 0.365; P = 0.015), hunger (3.56 ± 1.61; 0.308; P = 0.033), and PFC (4.22 ± 1.78; 0.314; P = 0.023), and with reduced sensations of fullness (-4.18 ± 1.94; 0.358; P = 0.038) and satiety (-3.83 ± 1.87; 0.295; P = 0.048). Lactation was associated with appetite, which in turn was related to PPWR. Appetite control should be explored to support postpartum weight management strategies. Novelty Postpartum weight retention was associated with appetite sensations, which were assessed throughout the day under conditions in which energy intake and expenditure were precisely matched. Lactation and other maternal metabolic factors, including carbohydrate oxidation and physical activity level may play a role in controlling appetite during the postpartum period.

The Canadian Partnership for Tomorrow Project: a pan-Canadian platform for research on chronic disease prevention

BACKGROUND

Understanding the complex interaction of risk factors that increase the likelihood of developing common diseases is challenging. The Canadian Partnership for Tomorrow Project (CPTP) is a prospective cohort study created as a population-health research platform for assessing the effect of genetics, behaviour, family health history and environment (among other factors) on chronic diseases.

METHODS

Volunteer participants were recruited from the general Canadian population for a confederation of 5 regional cohorts. Participants were enrolled in the study and core information obtained using 2 approaches: attendance at a study assessment centre for all study measures (questionnaire, venous blood sample and physical measurements) or completion of the core questionnaire (online or paper), with later collection of other study measures where possible. Physical measurements included height, weight, percentage body fat and blood pressure. Participants consented to passive follow-up through linkage with administrative health databases and active follow-up through recontact. All participant data across the 5 regional cohorts were harmonized.

RESULTS

A total of 307 017 participants aged 30-74 from 8 provinces were recruited. More than half provided a venous blood sample and/or other biological sample, and 33% completed physical measurements. A total of 709 harmonized variables were created; almost 25% are available for all participants and 60% for at least 220 000 participants.

INTERPRETATION

Primary recruitment for the CPTP is complete, and data and biosamples are available to Canadian and international researchers through a data-access process. The CPTP will support research into how modifiable risk factors, genetics and the environment interact to affect the development of cancer and other chronic diseases, ultimately contributing evidence to reduce the global burden of chronic disease.

Anthropometric changes and risk of diabetes: are there sex differences? A longitudinal study of Alberta's Tomorrow Project

OBJECTIVES

To characterise the sex-specific difference in the association between anthropometric changes and risk of diabetes in the general population in Canada.

SETTING AND PARTICIPANTS

From 2000 to 2008, Alberta's Tomorrow Project (ATP) invited Alberta's residents aged 35-69 years to a prospective cohort study. A total of 19 655 diabetes-free ATP participants having anthropometrics measured at the baseline and follow-ups were included.

DESIGN AND OUTCOME MEASURES

A longitudinal study design was used to examine the association between anthropometric changes and risk of diabetes and the sex difference in this association. Changes in weight, body mass index (BMI), waist circumference (WC) and waist-hip-ratio (WHR) were calculated as the difference between baseline and follow-up measures. Diabetes cases were identified using the Canadian National Diabetes Surveillance System algorithm with administrative healthcare data (2000-2015) linked to the ATP cohort. The sex-specific association between anthropometric changes and incidence of diabetes were examined by multivariable Cox regression models.

RESULTS

Changes in weight, BMI, WC and WHR over time were positively associated with incidence of diabetes in both men and women. The sex difference in risk of diabetes associated with 1 standard deviation (SD) increase in anthropometrics was 0.07 (95% CI -0.02 to 0.14) for weight, 0.08 (95% CI -0.03 to 0.17) for BMI, 0.07 (95% CI -0.02 to 0.15) for WC and 0.09 (95% CI 0.03 to 0.13) for WHR. Similar results were found in sex difference in the associations with changes per 5% and changes per categories (5% loss, ±5%, 5% gain).

CONCLUSIONS

The positive association between anthropometric changes and risk of diabetes was generally stronger in men than in women. However, this sex-specific difference of approximately 10% of the total risk associated with anthropometric changes had limited significance. For population-based public health programmes aiming to control obesity and incidence of diabetes, it may not be necessary to set up sex-specific goals for anthropometric reduction.

Abstract 2407: Stage shifting by modifying the determinants of cancer

Early detection of cancer is a major challenge because most tumors are asymptomatic in the early stages. However, if the cancer is caught early, it can be treated more effectively thereby improving survival rates. Many environmental, lifestyle and genetic risk factors for developing cancer have been identified; however, they collectively do not fully explain its etiology. By using health and lifestyle information of people along with their cancer screening history before they develop cancer, we hope to identify factors that can be modified to avoid diagnosis at later stages of disease. These identified factors will be evaluated immediately using simulated data that mimics real data without waiting years for results from intervention studies. Hence, the aim of our study is to explore patient and health care system factors associated with stage of cancer diagnosis and to explore reduction in stages at diagnosis by modifying identified factors using simulation methods. The study is based on results obtained from the analysis of the data collected from the participants in Alberta Tomorrow Project (ATP), a prospective cohort of over 50,000 adults (aged ≥35 years). More than 3,500 participants have been diagnosed with cancer since their enrollment in the ATP. Close to 80% of the breast and colorectal cancers, and 70% of the lung cancer were diagnosed at early stage (stages I and II) and late stage (stages III and IV), respectively. Using these information as prior knowledge, we simulated the stages of breast, lung, and colorectal cancers at diagnosis along with risk factors and screening interventions. The outcome (stage at diagnosis) was modeled on the ordinal scale (I-IV) using a popular ordinal logistic regression model, so-called proportional odds and partial proportional odds models, that assesses the strengths of the associations between ordinal outcomes and measured risk factors. Preliminary findings from our simulation study for either ordinal response model found that a change in combination of risk factors could increase the probability of shifting the stage of diagnosis. We also plan to explore a shift towards earlier stage at diagnosis by modifying selected environmental and lifestyle risk factors - for example, reducing the amount of time spent in the midday sun (reduced risk exposure), and increase the amount of vitamin D (increase protective factor exposure). This will be done systematically to identify the impact of factors individually and collectively. The comprehensive modeling of factors associated with cancer stage at diagnosis provides information simply not attainable in empirical studies. Using a simple framework of stage at diagnosis, we expect to identify factors that can be used by screening and prevention programs to identify individuals who may benefit from individualized screening practices or from targeted prevention messages, thereby increasing the proportion of cases diagnosed at earlier stages.

Citation Format: Gyanendra Pokharel, Paula J. Robson, Lorraine Shack, John J. Spinelli, Karen A. Kopciuk. Stage shifting by modifying the determinants of cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 2407.

The influence of energy metabolism on postpartum weight retention

BACKGROUND

Profiling postpartum energy metabolism may assist in optimizing weight management following childbirth.

OBJECTIVES

The aims of this study were to profile total energy expenditure (TEE), resting energy expenditure (REE), exercise energy expenditure, sleep energy expenditure, and respiratory quotient in women at 3 and 9 mo postpartum (3M-PP, 9M-PP, respectively), and to examine the association between energy metabolism and postpartum weight retention (PPWR).

METHODS

In this cohort study, 1-h REE (measured in a whole body calorimetry unit, WBCU) and body composition (BC, measured by dual-energy X-ray absorptiometry) were measured at 3M-PP and 9M-PP (n = 49). Cardiorespiratory fitness [measured by the predicted maximal volume of oxygen consumption (p$\dot{V}$O2 max), n = 47] and 24-h TEE (WBCU, n = 43) were assessed only at 9M-PP. Women were stratified as high (>4.8 kg) or low (≤ 4.8 kg) weight retainers. Two-way mixed repeated-measures ANOVA and longitudinal regression models were applied. Linear regression was used to generate an equation at 3M-PP from the BC data, to predict the REE at 9M-PP.

RESULTS

The fat mass at 3M-PP was positively associated with PPWR at 3M-PP (mean ± SE β: 0.09 ± 0.03; P = 0.005) and 9M-PP (β: 0.11 ± 0.04; P = 0.008), and negatively associated with REE at 3M-PP (β: -0.16 ± 0.02; P < 0.001) and TEE at 9M-PP (β: -0.15 ± 0.03; P < 0.001). REE was negatively associated with PPWR (β: -0.74; 95% CI: -1.29, -0.19; P = 0.0087). REE was 2 kcal/kg higher in low- vs. high-retainers at 3M-PP, and REE and TEE were both 4 kcal/kg higher in low- vs. high-retainers at 9M-PP. Low-retainers demonstrated an increase in REE greater than expected for changes in BC. PPWR was negatively associated with TEE (β: -0.08 ± 0.02; P = 0.0009) and p$\dot{V}$O2 max (β: -0.02 ± 0.01; P = 0.047); p$\dot{V}$O2 max was 7 mL · kg-1 · min-1 higher in low- vs. high-retainers (P = 0.047).

CONCLUSIONS

Energy metabolism, BC, and cardiorespiratory fitness may be associated with weight regulation and its trajectory during the postpartum period. This provides the foundation for future strategies to promote appropriate postpartum weight management.

School-Age Children Can Recall Some Foods and Beverages Consumed the Prior Day Using the Automated Self-Administered 24-Hour Dietary Assessment Tool (ASA24) without Assistance

BACKGROUND

Technological innovations allow for collection of 24-h recalls (24HRs) in a broader range of studies than previously possible. The web-based Automated Self-Administered 24-Hour Dietary Assessment Tool (ASA24) has been shown to be feasible and to perform well in capturing true intake among adults. However, data to inform use with children are limited.

OBJECTIVE

This observational feeding study was conducted to evaluate children's ability to accurately report a lunchtime meal using ASA24 without assistance.

METHODS

The study was conducted among children (n = 100) aged 10-13 y within a school setting. Students were served an individual cheese pizza, baby carrots, ranch dip, yogurt, a cookie, and 1 choice of water, juice, or milk. Plate waste was collected and weighed. The next day, participants completed ASA24 and a sociodemographic questionnaire. Descriptive statistics were generated to determine match rates by food item and age, and linear regression analyses were conducted to examine associations between sociodemographic characteristics and accuracy of reported energy and nutrient intake. Associations between true and reported energy and nutrient intakes and portion sizes were assessed with use of t tests.

RESULTS

Just under half (49%) of children fully completed ASA24 (median time, 41 min). Children reported an exact, close, or far match for 58% of all foods and beverages consumed, ranging from 29% for dip to 76% for pizza, but also reported some items not consumed as part of the study meal. Older children completed the recall in a shorter time than younger children (mean 31 among 13 y compared with 52 min among 10 y). Intakes of energy (39%), protein (33%), and sodium (78%) were significantly overestimated, whereas portion sizes for cookies (53%) and juice (69%) were underestimated.

CONCLUSIONS

Children can report some foods and drinks consumed using ASA24, but our findings suggest challenges with independent completion, necessitating research to examine strategies, such as training and resources, to support data quality.

Harmonization of the Health and Risk Factor Questionnaire data of the Canadian Partnership for Tomorrow Project: a descriptive analysis

BACKGROUND

The Canadian Partnership for Tomorrow Project is a multistudy platform integrating the British Columbia Generations Project, Alberta's Tomorrow Project, the Ontario Health Study, CARTaGENE (Quebec) and the Atlantic Partnership for Tomorrow's Health. This paper describes the process used to harmonize the Health and Risk Factor Questionnaire data and provides an overview of the key information required to properly use the core data set generated.

METHODS

This is a descriptive analysis of the harmonization process that was developed on the basis of the Maelstrom Research guidelines for retrospective harmonization. Core variables (DataSchema) to be generated across cohorts were defined and the potential for cohort-specific data sets to generate the DataSchema variables was assessed. Where relevant, algorithms were developed and applied to process cohort-specific data into the DataSchema format, and information to be provided to data users was documented.

RESULTS

The Health and Risk Factor Questionnaire DataSchema (version 2.0, October 2017) comprised 694 variables. The assessment of harmonization potential for the variables over 12 cohort-specific data sets resulted in 6799 (81.6%) of the variables being considered as harmonizable. A total of 307 017 participants were included in the harmonized data set. Through the cohort data portal, researchers can find information about the definitions of variables, harmonization potential, algorithms applied to generate harmonized variables and participant distributions.

INTERPRETATION

The harmonization process enabled the creation of a unique data set including data on health and risk factors from over 307 000 Canadians. These data, in combination with complementary data sets, can be used to investigate the impact of biological, environmental and behavioural factors on cancer and chronic diseases.

The use of whole body calorimetry to compare measured versus predicted energy expenditure in postpartum women

BACKGROUND

Accurate assessment of energy expenditure may support weight-management recommendations. Measuring energy expenditure for each postpartum woman is unfeasible; therefore, accurate predictive equations are needed.

OBJECTIVES

This study compared measured with predicted resting energy expenditure (REE) and total energy expenditure (TEE) in postpartum women.

METHODS

This was a longitudinal observational study. REE was measured at 3 mo postpartum (n = 52) and 9 mo postpartum (n = 49), whereas TEE was measured once at 9 mo postpartum (n = 43) by whole body calorimetry (WBC). Measured REE (REEWBC) was compared with 17 predictive equations; measured TEE plus breast milk energy output (ERWBC) was compared with the estimated energy requirements/Dietary Reference Intakes equation (EERDRI). Fat and fat-free mass were measured by dual-energy X-ray absorptiometry. Group-level agreement was assessed by the Pearson correlation, paired t test, and Bland-Altman (bias) analyses. Individual-level accuracy was assessed with the use of Bland-Altman limits of agreement, and by the percentage of women with predicted energy expenditure within 10% of measured values ("accuracy").

RESULTS

The cohort was primarily Caucasian (90%). At a group level, the best equation predicting REEWBC was the DRI at 3 mo postpartum (-7 kcal, -0.1%; absolute and percentage bias, respectively), and the Harris-Benedict at 9 mo postpartum (-17 kcal, -0.5%). At an individual level, the Food and Agriculture Organization/World Health Organization/United Nations University (FAO/WHO/UNU) height and weight equation was the most accurate at 3 mo postpartum (100% accuracy) and 9 mo postpartum (98% accuracy), with the smallest limits of agreement. Equations including body composition variables were not more accurate. Compared with ERWBC, EERDRI bias was -36 kcal, with inaccurate predictions in 33% of women.

CONCLUSIONS

Many REE predictive equations were accurate for group assessment, with the FAO/WHO/UNU height and weight equation having the highest accuracy for individuals. EERDRI performed well at a group level, but inaccurately for 33% of women. A greater understanding of the physiology driving energy expenditure in the postpartum period is needed to better predict TEE and ultimately guide effective weight-management recommendations.

Dietary Patterns Prior to Pregnancy and Associations with Pregnancy Complications

Few studies have explored pre-pregnancy diet and its relationship with pregnancy outcomes. The objectives of this study were to: (1) derive pre-pregnancy dietary patterns for women enrolled in a prospective cohort in the province of Alberta, Canada; (2) describe associations between dietary patterns and socio-demographic characteristics; and (3) describe associations between dietary patterns and pregnancy complications. Upon enrolment into the Alberta Pregnancy Outcomes and Nutrition (APrON) study (median age of gestation, 17 weeks), women (n = 1545) completed a validated 142-item food frequency questionnaire recording food and beverages consumed “in the 12 months prior to pregnancy”. Other assessments included pre-pregnancy body mass index (BMI), gestational weight gain, gestational hypertension, gestational diabetes, and socio-demographic characteristics. Dietary patterns were derived using principal components analysis. Scores were calculated to represent adherence with each dietary pattern retained. Four dietary patterns were retained, accounting for 22.9% of the variation in the overall diet. Dietary patterns were named the “healthy”, “meat and refined carbohydrate”, “beans, cheese and salad” or “tea and coffee” patterns. Higher “healthy” pattern scores prior to pregnancy were associated with lower odds of developing gestational hypertension during pregnancy (adjusted Odds Ratio (OR): 0.6, 95% Confidence Intervals (CI): 0.4, 0.9). Diet prior to pregnancy is an important target for interventions and may reduce the likelihood of developing complications such as gestational hypertension during pregnancy.

Systemic use of antibiotics and risk of diabetes in adults: A nested case-control study of Alberta's Tomorrow Project

AIMS

Previous observational studies using administrative health records have suggested an increased risk of diabetes with use of antibiotics. However, unmeasured confounding factors may explain these results. This study characterized the association between systemic use of antibiotics and risk of diabetes in a cohort of adults in Canada, accounting for both clinical and self-reported disease risk factors.

MATERIALS AND METHODS

In this nested case-control study, we used data from Alberta's Tomorrow Project (ATP), a longitudinal cohort study in Canada, and the linked administrative health records (2000-2015). Incident cases of diabetes were matched with up to 8 age and sex-matched controls per case. Conditional logistic regression was used to examine the association between antibiotic exposures and incident diabetes after sequentially adjusting for important clinical and lifestyle factors.

RESULTS

This study included 1676 cases of diabetes and 13 401 controls. Although 17.9% of cases received more than 5 courses of antibiotics, compared to 13.8% of controls (P < .0001), the association between antibiotic use and risk of diabetes was progressively reduced as important clinical and lifestyle factors were accounted for. In fully adjusted models, compared to participants with 0 to 1 courses of antibiotics, participants receiving more antibiotics had no increased risk of diabetes [Odds Ratio, 0.97 (0.83-1.13) for 2 to 4 courses and 0.98 (0.82-1.18) for ≥5 courses].

CONCLUSIONS

After adjustment for clinical and difficult-to-capture lifestyle data, we found no association between systemic use of antibiotics and risk of diabetes. Our results suggest that those positive associations observed in previous studies using only administrative records might have been confounded.

Serum Metabolomics of Activity Energy Expenditure and its Relation to Metabolic Syndrome and Obesity

Modifiable lifestyle factors, including exercise and activity energy expenditure (AEE), may attenuate the unfavorable health effects of obesity, such as risk factors of metabolic syndrome (MetS). However, the underlying mechanisms are not clear. In this study we sought to investigate whether the metabolite profiles of MetS and adiposity assessed by body mass index (BMI) and central obesity are inversely correlated with AEE and physical activity. We studied 35 men and 47 women, aged 30-60 years, using doubly labeled water to derive AEE and the Sedentary Time and Activity Reporting Questionnaire (STAR-Q) to determine the time spent in moderate and vigorous physical activity. Proton nuclear magnetic resonance spectroscopy was used for serum metabolomics analysis. Serine and glycine were found in lower concentrations in participants with more MetS risk factors and greater adiposity. However, serine and glycine concentrations were higher with increasing activity measures. Metabolic pathway analysis and recent literature suggests that the lower serine and glycine concentrations in the overweight/obese state could be a consequence of serine entering de novo sphingolipid synthesis. Taken together, higher levels of AEE and physical activity may play a crucial part in improving metabolic health in men and women with and without MetS risk factors.

Changes in body mass index and incidence of diabetes: A longitudinal study of Alberta's Tomorrow Project Cohort

Although obesity is a known risk factor for diabetes, the impact of body mass index (BMI) changes over time, especially BMI reduction, on diabetes development is less than clear. The objective of this study is to characterize the association between BMI changes over time and incidence of diabetes in a cohort of adults in Alberta. From 2000 to 2008, Alberta's Tomorrow Project (ATP) enrolled participants aged 35-69 to a population-based prospective cohort study. BMI was calculated from self-reported height and weight; change in BMI (∆BMI) was calculated as the difference between baseline and follow-up measurements. Diabetes cases were identified using the Canadian National Diabetes Surveillance System algorithm applied to linked administrative data (2000-2015). Multivariable Cox regression was used to examine the association between ∆BMI and incidence of diabetes. In a subset of the ATP cohort (n=19,164), 1168 incident cases of diabetes were identified during 198,853person-years of follow-up. Overall, BMI increase was associated with increased risk and BMI reduction was associated with reduced risk of diabetes. Particularly, compared to minimal BMI change (±5%), moderate (5%-10%) reduction in BMI was associated with 34% (95% CI: 12%-51%) reduction in risk of diabetes in participants with obesity; whereas 10% or greater increase in BMI was associated with an increased risk of diabetes of 64% or more in participants with overweight and obesity; in participants with normal and underweight, BMI changes was not apparently associated with risk of diabetes. Public health programs promoting weight loss, even at a moderate extent, would reduce risk of diabetes.

Alcohol consumption and low-risk drinking guidelines among adults: a cross-sectional analysis from Alberta's Tomorrow Project

INTRODUCTION

Moderate to heavy alcohol consumption is a risk factor for all-cause mortality and cancer incidence. Although cross-sectional data are available through national surveys, data on alcohol consumption in Alberta from a large prospective cohort were not previously available. The goal of these analyses was to characterize the levels of alcohol consumption among adults from the Alberta's Tomorrow Project in the context of cancer prevention guidelines. Furthermore, we conducted analyses to examine the relationships between alcohol consumption and other high-risk or risk-related behaviours.

METHODS

Between 2001 and 2009, 31 072 men and women aged 35 to 69 years were enrolled into Alberta's Tomorrow Project, a large provincial cohort study. Data concerning alcohol consumption in the past 12 months were obtained from 26 842 participants who completed self-administered health and lifestyle questionnaires. We conducted cross-sectional analyses on daily alcohol consumption and cancer prevention guidelines for alcohol use in relation to sociodemographic factors. We also examined the combined prevalence of alcohol consumption and tobacco use, obesity and comorbidities.

RESULTS

Approximately 14% of men and 12% of women reported alcohol consumption exceeding recommendations for cancer prevention. Higher alcohol consumption was reported in younger age groups, urban dwellers, those with higher incomes and those who consumed more red meat. Moreover, volume of daily alcohol consumption was positively associated with current tobacco use in both men and women. Overall, men were more likely to fall in the moderate and high-risk behavioural profiles and show higher daily alcohol consumption patterns compared to women.

CONCLUSION

Despite public health messages concerning the adverse impact of alcohol consumption, a sizeable proportion of Alberta's Tomorrow Project participants consumed alcohol in excess of cancer prevention recommendations. Continued strategies to promote low-risk drinking among those who choose to drink could impact future chronic disease risk in this population.

Measures of excess body weight and anthropometry among adult Albertans: cross-sectional results from Alberta's tomorrow project cohort

Background

Excess body weight during adulthood has been consistently associated with all-cause mortality, cardiovascular disease, and cancer at multiple sites among other chronic diseases. We describe the prevalence of excess body weight and abdominal obesity reported by participants enrolled in Alberta’s Tomorrow Project (ATP).

Methods

ATP is a geographically-based cohort study conducted among adults aged 35–69 years from across the province of Alberta. Participants completed anthropometric measures and health and lifestyle questionnaires at enrolment. Overweight and obese were categorized as a body mass index (BMI) of 25.0–29.9 kg/m² and ≥30 kg/m², respectively. Abdominal obesity was categorized using cut-offs of waist circumference of >94 cm for men and >80 cm for women and waist-tp-hip ratio cut-offs of >0.90 for men and >0.85 for women.

Results

BMI and hip and waist circumference data were obtained from 12,062 men and 18,853 women enrolled between 2001 and 2009. Overall, 76.8% of men and 59.5% of women reported a BMI ≥25 kg/m². The proportions of overweight and obese were significantly higher in older age groups (p < 0.001). In addition, the proportion of participants reporting being overweight and obese was higher among lower education (p < 0.001) and lower income groups (p < 0.001). Overall, approximately two thirds of men and women in ATP cohort reported abdominal obesity. Overweight, obesity and abdominal obesity were all associated with a history of several cardiometabolic chronic conditions including hypertension, heart attack, angina, high cholesterol, stroke and diabetes.

Conclusion

A large majority of ATP participants were overweight and carried excess abdominal fat. Strategies to improve energy balance among Albertans are encouraged and may have a notable impact on future chronic disease burden.

Electronic supplementary material

The online version of this article (10.1186/s12889-017-4887-2) contains supplementary material, which is available to authorized users.

Diet quality is associated with reduced incidence of cancer and self-reported chronic disease: Observations from Alberta's Tomorrow Project

The objective of this study was to assess diet quality using the Healthy Eating Index-2005 Canada (HEI-2005-Canada) and its association with risk of cancer and chronic disease in a sample of Alberta's Tomorrow Project (ATP) participants. Food frequency questionnaires completed by 25,169 participants (38% men; mean age 50.3 (9.2)) enrolled between 2000 and 2008 were used to calculate HEI-2005-Canada scores. Data from a subset of participants (n=10,735) who reported no chronic disease at enrollment were used to investigate the association between HEI-2005-Canada score and development of self-reported chronic disease at follow-up (2008). Participants were divided into HEI-2005-Canada score quartiles. Cox proportional hazards models were used to estimate hazard ratios (HR) and 95% confidence intervals (CI) for cancer and chronic disease incidence. In this cohort, mean HEI-2005-Canada scores for men and women were 50.9 and 55.5 (maximum range 0-100), respectively. In men, higher HEI-2005-Canada score (Q4 vs. Q1) was associated with lower cancer risk (HR (95% CI) 0.63 (0.49-0.83)) over the course of follow-up (mean (SD)=10.4 (2.3) years); the same was not observed in women. In contrast, higher overall HEI-2005-Canada score (Q4 vs. Q1) was associated with lower risk of self-reported chronic disease (0.85 (0.75-0.97)) in both men and women over follow-up (4.2 (2.3) years). In conclusion, in this cohort better diet quality was associated with a lower risk of cancer in men and lower risk of chronic disease in both sexes. Future studies with longer follow-up and repeated measures of diet may be helpful to elucidate sex-specific associations between dietary quality and disease outcomes.

Adherence to Canada's Food Guide Recommendations during Pregnancy: Nutritional Epidemiology and Public Health

Background: In Canada, pregnant women are typically referred to Canada's Food Guide (CFG), a set of national dietary recommendations designed to promote adequate nutrient intake. Pregnant women are also advised to gain weight within the Institute of Medicine guidelines, which differ by prepregnancy body mass index (BMI). However, CFG recommendations do not account for prepregnancy BMI and provide no guidance on "less healthy" (LH) foods. Objective: The aim of this study was to score women's diets according to adherence to CFG recommendations and consumption of LH foods and to examine differences between these diet scores by prepregnancy BMI. Methods: Participants enrolled in the APrON (Alberta Pregnancy Outcomes and Nutrition) prospective cohort study completed a 24-h recall in their second trimester (n = 1630). A score was created on the basis of each daily dietary CFG recommendation met, ranging from 0 to 9. The distribution of consumption (grams per day) of 8 LH food groups was given a score of 0 (none) or 1, 2, or 3 (representing the lowest, middle, or highest tertiles, respectively) and summed giving a total LH score of 0-24. Results: There were few differences in CFG recommendations met by prepregnancy BMI status, although fewer women who were overweight or obese prepregnancy met the specific recommendation to consume 7-8 servings of fruit or vegetables/d than did those who were under- or normal weight (47% and 41% compared with 50% and 54%, respectively). Although differences were small, women who were obese prepregnancy had lower CFG scores (β = -0.28; 95% CI:-0.53, -0.02) and higher LH scores (β = 0.45; 95% CI: 0.04, 0.86) than did those who were normal weight. Conclusion: The study results suggest that more attention may need to be paid to individualized counseling on dietary recommendations that take account of prepregnancy BMI.

Self-Report Dietary Assessment Tools Used in Canadian Research: A Scoping Review

Choosing the most appropriate dietary assessment tool for a study can be a challenge. Through a scoping review, we characterized self-report tools used to assess diet in Canada to identify patterns in tool use and to inform strategies to strengthen nutrition research. The research databases Medline, PubMed, PsycINFO, and CINAHL were used to identify Canadian studies published from 2009 to 2014 that included a self-report assessment of dietary intake. The search elicited 2358 records that were screened to identify those that reported on self-report dietary intake among nonclinical, non-Aboriginal adult populations. A pool of 189 articles (reflecting 92 studies) was examined in-depth to assess the dietary assessment tools used. Food-frequency questionnaires (FFQs) and screeners were used in 64% of studies, whereas food records and 24-h recalls were used in 18% and 14% of studies, respectively. Three studies (3%) used a single question to assess diet, and for 3 studies the tool used was not clear. A variety of distinct FFQs and screeners, including those developed and/or adapted for use in Canada and those developed elsewhere, were used. Some tools were reported to have been evaluated previously in terms of validity or reliability, but details of psychometric testing were often lacking. Energy and fat were the most commonly studied, reported by 42% and 39% of studies, respectively. For ∼20% of studies, dietary data were used to assess dietary quality or patterns, whereas close to half assessed ≤5 dietary components. A variety of dietary assessment tools are used in Canadian research. Strategies to improve the application of current evidence on best practices in dietary assessment have the potential to support a stronger and more cohesive literature on diet and health. Such strategies could benefit from national and global collaboration.

Dietary assessment is a critical element of health research - Perspective from the Partnership for Advancing Nutritional and Dietary Assessment in Canada

Challenges and complexities associated with assessing dietary intakes are numerous, but not insurmountable. This opinion paper from Canadian researchers draws attention to the importance of building capacity and providing funding opportunities for research in dietary assessment methods in Canada and elsewhere. Such strategies would contribute to a better understanding of the roles played by diet in human health and better translation of this information into the most meaningful and effective dietary guidelines, policies, and interventions.

Design, methods and demographics from phase I of Alberta's Tomorrow Project cohort: a prospective cohort profile

BACKGROUND

Prospective cohorts have the potential to support multifactorial, health-related research, particularly if they are drawn from the general population, incorporate active and passive follow-up and permission is obtained to allow access by researchers to data repositories. This paper describes Phase I of the Alberta's Tomorrow Project cohort, a broad-based research platform designed to support investigations into factors that influence cancer and chronic disease risk.

METHODS

Adults aged 35-69 years living in Alberta, Canada, with no previous cancer diagnosis other than nonmelanoma skin cancer were recruited to the project by telephone-based random digit dialling. Participants were enrolled if they returned a Health and Lifestyle Questionnaire. Past year diet and physical activity questionnaires were mailed 3 months after enrolment. Consent was sought for active follow-up and linkage with administrative databases. Depending on enrolment date, participants were invited to complete up to 2 follow-up questionnaires (2004 and 2008).

RESULTS

Between 2001 and 2009, 31 072 (39% men) participants (mean age 50.2 [± 9.2] yr) were enrolled and 99% consented to linkage with administrative databases. Participants reported a wide range of educational attainment and household income. Compared with provincial surveillance data from the Canadian Community Health Survey, Alberta's Tomorrow Project participants had higher body mass index, lower prevalence of smoking and similar distribution of chronic health conditions. Follow-up questionnaires were completed by 83% and 72% of participants in 2004 and 2008, respectively. Robust quality control measures resulted in low frequencies of missing data.

INTERPRETATION

Alberta's Tomorrow Project provides a robust platform, based on a prospective cohort design, to support research into risk factors for cancer and chronic disease.

Patterns and trajectories of gestational weight gain: a prospective cohort study

BACKGROUND

Gestational weight gain in excess of or below Health Canada's guidelines is known to increase the risk of adverse outcomes for both the woman and her baby. This study describes patterns and trajectories of total and rate of gestational weight gain in a large prospective cohort of pregnant women and adolescents in the Alberta Pregnancy Outcomes and Nutrition study.

METHODS

We collected weight and height data for 1541 pregnant adolescents and women (mean age 31 years, < 27 weeks' gestation) recruited through advertisements and physicians' offices in Calgary and Edmonton between May 2009 and November 2012. Data were collected once during each trimester following enrolment and once at about 3 months post partum. The participants were categorized according to their prepregnancy body mass index (BMI) as underweight, of normal weight, overweight or obese. We calculated distributions of total and weekly rates of weight gain and determined trajectories of weight gain for each prepregnancy BMI category.

RESULTS

Of the 1541 participants, 761 (49.4%) exceeded Health Canada's guidelines for total gestational weight gain, and 272 (17.6%) gained less weight than recommended. A total of 63 (19.2%) and 38 (23.6%) participants categorized as overweight or obese, respectively, exceeded the recommended upper limit by 5 to less than 10 kg, and 53 (16.2%) and 27 (16.8%), respectively, exceeded the upper limit by at least 10 kg. Ninety-five participants (30.3%) in the overweight group and 59 (39.6%) of those in the obese group gained weight at more than double the recommended rate between the second and third trimesters. The median weight gain for participants in the normal, overweight and obese categories had exceeded recommended upper limits by about 30, 20 and 18 weeks' gestation, respectively.

INTERPRETATION

Adherence to Health Canada's guidelines for gestational weight gain was low. Excess gestational weight gain was most marked among those with a prepregnancy BMI in the overweight or obese category. The findings suggest that weight management in pregnancy is challenging and complex. Messages and supports that are tailored for women in different prepregnancy BMI categories may help to improve guideline-concordant gestational weight gain.

Cannabinoids and schizophrenia: therapeutic prospects

Approximately one third of patients diagnosed with schizophrenia do not achieve adequate symptom control with standard antipsychotic drugs (APs). Some of these may prove responsive to clozapine, but non-response to APs remains an important clinical problem and cause of increased health care costs. In a significant proportion of patients, schizophrenia is associated with natural and iatrogenic metabolic abnormalities (obesity, dyslipidaemia, impaired glucose tolerance or type 2 diabetes mellitus), hyperadrenalism and an exaggerated HPA response to stress, and chronic systemic inflammation. The endocannabinoid system (ECS) in the brain plays an important role in maintaining normal mental health. ECS modulates emotion, reward processing, sleep regulation, aversive memory extinction and HPA axis regulation. ECS overactivity contributes to visceral fat accumulation, insulin resistance and impaired energy expenditure. The cannabis plant synthesises a large number of pharmacologically active compounds unique to it known as phytocannabinoids. In contrast to the euphoric and pro-psychotic effects of delta-9-tetrahydrocannabinol (THC), certain non-intoxicating phytocannabinoids have emerged in pre-clinical and clinical models as potential APs. Since the likely mechanism of action does not rely upon dopamine D2 receptor antagonism, synergistic combinations with existing APs are plausible. The anti-inflammatory and immunomodulatory effects of the non-intoxicating phytocannabinoid cannabidiol (CBD) are well established and are summarised below. Preliminary data reviewed in this paper suggest that CBD in combination with a CB1 receptor neutral antagonist could not only augment the effects of standard APs but also target the metabolic, inflammatory and stress-related components of the schizophrenia phenotype.

The Sedentary Time and Activity Reporting Questionnaire (STAR-Q): reliability and validity against doubly labeled water and 7-day activity diaries

We determined measurement properties of the Sedentary Time and Activity Reporting Questionnaire (STAR-Q), which was designed to estimate past-month activity energy expenditure (AEE). STAR-Q validity and reliability were assessed in 102 adults in Alberta, Canada (2009-2011), who completed 14-day doubly labeled water (DLW) protocols, 7-day activity diaries on day 15, and the STAR-Q on day 14 and again at 3 and 6 months. Three-month reliability was substantial for total energy expenditure (TEE) and AEE (intraclass correlation coefficients of 0.84 and 0.73, respectively), while 6-month reliability was moderate. STAR-Q-derived TEE and AEE were moderately correlated with DLW estimates (Spearman's ρs of 0.53 and 0.40, respectively; P < 0.001), and on average, the STAR-Q overestimated TEE and AEE (median differences were 367 kcal/day and 293 kcal/day, respectively). Body mass index-, age-, sex-, and season-adjusted concordance correlation coefficients (CCCs) were 0.24 (95% confidence interval (CI): 0.07, 0.36) and 0.21 (95% CI: 0.11, 0.32) for STAR-Q-derived versus DLW-derived TEE and AEE, respectively. Agreement between the diaries and STAR-Q (metabolic equivalent-hours/day) was strongest for occupational sedentary time (adjusted CCC = 0.76, 95% CI: 0.64, 0.85) and overall strenuous activity (adjusted CCC = 0.64, 95% CI: 0.49, 0.76). The STAR-Q demonstrated substantial validity for estimating occupational sedentary time and strenuous activity and fair validity for ranking individuals by AEE.

Conditions associated with circulating tumor-associated folate receptor 1 protein in healthy men and women

Background

Serum concentrations of the tumor-associated folate receptor 1 (FOLR1) protein may be a marker for early cancer detection, yet concentrations have also been detected in cancer-free women. We investigated the conditions associated with circulating FOLR1 protein in healthy individuals and sought to clarify the range of normal serum values.

Methods

Sera of cancer-free men and women (N = 60) enrolled in a population-based cohort study in Alberta, Canada were analyzed for FOLR1 protein using an electrochemical luminescence immunoassay. Dietary, lifestyle, medical and reproductive history information was collected by questionnaires. Differences in serum FOLR1 concentrations between groups were assessed by non-parametric tests, and predictors of serum FOLR1 concentrations were estimated using multivariable linear regression.

Results

Median serum FOLR1 concentration was higher in women (491 pg/ml, range = 327–693 pg/ml) than in men (404 pg/ml, range = 340–682 pg/ml), P = 0.001. FOLR1 concentration was also positively associated with vitamin A intake (P = 0.02), and showed positive trends with age and with oral contraceptive hormone use among women and an inverse trend with body mass index. All variables examined explained almost half of the variation in serum FOLR1 (model R² = 0.44, P = 0.04); however, the retention of gender (P = 0.003) and vitamin A intake (P = 0.03) together explained 20% (P = 0.001) of serum FOLR1 variation. No other predictor was significant at P<0.05.

Conclusions

The positive association between serum FOLR1 concentration and female gender independent of an age effect suggests caution against statements to exploit serum FOLR1 for early cancer detection without further understanding the biological underpinnings of these observations. Serum FOLR1 concentrations may be influenced by the steroid retinoic acid (vitamin A) but do not appear to be associated with folate nutritional status. These findings require confirmation in larger independent studies.

Assessing SNP-SNP interactions among DNA repair, modification and metabolism related pathway genes in breast cancer susceptibility

Genome-wide association studies (GWASs) have identified low-penetrance common variants (i.e., single nucleotide polymorphisms, SNPs) associated with breast cancer susceptibility. Although GWASs are primarily focused on single-locus effects, gene-gene interactions (i.e., epistasis) are also assumed to contribute to the genetic risks for complex diseases including breast cancer. While it has been hypothesized that moderately ranked (P value based) weak single-locus effects in GWASs could potentially harbor valuable information for evaluating epistasis, we lack systematic efforts to investigate SNPs showing consistent associations with weak statistical significance across independent discovery and replication stages. The objectives of this study were i) to select SNPs showing single-locus effects with weak statistical significance for breast cancer in a GWAS and/or candidate-gene studies; ii) to replicate these SNPs in an independent set of breast cancer cases and controls; and iii) to explore their potential SNP-SNP interactions contributing to breast cancer susceptibility. A total of 17 SNPs related to DNA repair, modification and metabolism pathway genes were selected since these pathways offer a priori knowledge for potential epistatic interactions and an overall role in breast carcinogenesis. The study design included predominantly Caucasian women (2,795 cases and 4,505 controls) from Alberta, Canada. We observed two two-way SNP-SNP interactions (APEX1-rs1130409 and RPAP1-rs2297381; MLH1-rs1799977 and MDM2-rs769412) in logistic regression that conferred elevated risks for breast cancer (P_interaction<7.3×10⁻³). Logic regression identified an interaction involving four SNPs (MBD2-rs4041245, MLH1-rs1799977, MDM2-rs769412, BRCA2-rs1799943) (P_permutation = 2.4×10⁻³). SNPs involved in SNP-SNP interactions also showed single-locus effects with weak statistical significance, while BRCA2-rs1799943 showed stronger statistical significance (P_{correlation/trend} = 3.2×10⁻⁴) than the others. These single-locus effects were independent of body mass index. Our results provide a framework for evaluating SNPs showing statistically weak but reproducible single-locus effects for epistatic effects contributing to disease susceptibility.

Identification of a breast cancer susceptibility locus at 4q31.22 using a genome-wide association study paradigm

More than 40 single nucleotide polymorphisms (SNPs) for breast cancer susceptibility were identified by genome-wide association studies (GWASs). However, additional SNPs likely contribute to breast cancer susceptibility and overall genetic risk, prompting this investigation for additional variants. Six putative breast cancer susceptibility SNPs identified in a two-stage GWAS that we reported earlier were replicated in a follow-up stage 3 study using an independent set of breast cancer cases and controls from Canada, with an overall cumulative sample size of 7,219 subjects across all three stages. The study design also encompassed the 11 variants from GWASs previously reported by various consortia between the years 2007–2009 to (i) enable comparisons of effect sizes, and (ii) identify putative prognostic variants across studies. All SNP associations reported with breast cancer were also adjusted for body mass index (BMI). We report a strong association with 4q31.22-rs1429142 (combined per allele odds ratio and 95% confidence interval = 1.28 [1.17–1.41] and P_combined = 1.5×10⁻⁷), when adjusted for BMI. Ten of the 11 breast cancer susceptibility loci reported by consortia also showed associations in our predominantly Caucasian study population, and the associations were independent of BMI; four FGFR2 SNPs and TNRC9-rs3803662 were among the most notable associations. Since the original report by Garcia-Closas et al. 2008, this is the second study to confirm the association of 8q24.21-rs13281615 with breast cancer outcomes.

Hours spent and energy expended in physical activity domains: results from the Tomorrow Project cohort in Alberta, Canada

Background

Knowledge of adult activity patterns across domains of physical activity is essential for the planning of population-based strategies that will increase overall energy expenditure and reduce the risk of obesity and related chronic diseases. We describe domain-specific hours of activity and energy expended among participants in a prospective cohort in Alberta, Canada.

Methods

The Past Year Total Physical Activity Questionnaire was completed by 15,591 Tomorrow Project^® participants, between 2001 and 2005 detailing physical activity type, duration, frequency and intensity. Domain-specific hours of activity and activity-related energy expenditure, expressed as a percent of total energy expenditure (TEE) (Mean (SD); Median (IQR)) are reported across inactive (<1.4), low active (1.4 to 1.59), active (1.6 to 1.89) and very active (≥ 1.9) Physical Activity Level (PAL = TEE:REE) categories.

Results

In very active women and amongst all men except those classified as inactive, activity-related energy expenditure comprised primarily occupational activity. Amongst inactive men and women in active, low active and inactive groups, activity-related energy expenditure from household activity was comparable to, or exceeded that for occupational activity. Leisure-time activity-related energy expenditure decreased with decreasing PAL categories; however, even amongst the most active men and women it accounted for less than 10 percent of TEE. When stratified by employment status, leisure-time activity-related energy expenditure was greatest for retired men [mean (SD): 10.8 (8.5) percent of TEE], compared with those who were fully employed, employed part-time or not employed. Transportation-related activity was negligible across all categories of PAL and employment status.

Conclusion

For the inactive portion of this population, active non-leisure activities, specifically in the transportation and occupational domains, need to be considered for inclusion in daily routines as a means of increasing population-wide activity levels. Environmental and policy changes to promote active transport and workplace initiatives could increase overall daily energy expenditure through reducing prolonged sitting time.

Case-control study of dietary patterns and endometrial cancer risk

Dietary patterns, rather than intakes of specific foods or nutrients, may influence risk of endometrial cancer (EC). This population-based case-control study in Canada (2002-2006) included incident EC cases (n = 506) from the Alberta Cancer Registry and controls frequency age-matched to cases (n = 981). Past-year dietary patterns were defined using factor analysis of food frequency questionnaire data. Logistic regression was used to estimate EC risk within quartiles of dietary patterns. Three patterns (sweets, meat, plants) explained 23% of the variance in the dietary data. In multivariable models, EC risk was significantly reduced by 30% for women in the highest quartile of the healthier plants pattern (OR = 0.70, 95% CI 0.50-0.98, P trend = 0.02). When stratified by body mass index (BMI; kg/m(2)), risk was further reduced among overweight or obese women with a BMI ≥25 (OR = 0.57, 95% CI 0.39-0.83; P trend = 0.004). EC was not associated with the less healthy sweets and meat patterns. However, risk was modestly, but not significantly, elevated for higher intakes of the meat pattern among overweight or obese women. A mostly plant-based dietary pattern may reduce EC risk. Recommendations for risk reduction should focus on maintaining a healthy weight and the role of diet should be studied further.

Exploring statistical approaches to diminish subjectivity of cluster analysis to derive dietary patterns: The Tomorrow Project

Dietary patterns derived by cluster analysis are commonly reported with little information describing how decisions are made at each step of the analytical process. Using food frequency questionnaire data obtained in 2001-2007 on Albertan men (n = 6,445) and women (n = 10,299) aged 35-69 years, the authors explored the use of statistical approaches to diminish the subjectivity inherent in cluster analysis. Reproducibility of cluster solutions, defined as agreement between 2 cluster assignments, by 3 clustering methods (Ward's minimum variance, flexible beta, K means) was evaluated. Ratios of between- versus within-cluster variances were examined, and health-related variables across clusters in the final solution were described. K means produced cluster solutions with the highest reproducibility. For men, 4 clusters were chosen on the basis of ratios of between- versus within-cluster variances, but for women, 3 clusters were chosen on the basis of interpretability of cluster labels and descriptive statistics. In comparison with those in other clusters, men and women in the "healthy" clusters by greater proportions reported normal body mass index, smaller waist circumference, and lower energy intakes. The authors' approach appeared helpful when choosing the clustering method for both sexes and the optimal number of clusters for men, but additional analyses are required to understand why it performed differently for women.

The epidemiology of weight perception: perceived versus self-reported actual weight status among Albertan adults

BACKGROUND

To understand, prevent, and manage weight-related health issues, researchers and clinicians rely on the ability to identify those at risk. Prevention and management strategies may also rely on accurate self-perception of weight and body composition in the general population.

METHODS

We analyzed data from The Tomorrow Project (n = 7,436), a prospective cohort study enrolling adults aged 35-69 years, in Alberta, Canada. Weight perception accuracy was defined based on body mass index (BMI), waist circumference (WC), and a combined (BMI and WC) risk profile.

RESULTS

The majority of participants correctly perceived themselves as overweight. Women were more accurate than men in identifying themselves as overweight. In terms of inaccuracy, more normal-weight women than men perceived themselves to be overweight, while more overweight men than women perceived themselves as about the right weight. When using the combined risk profile, all men with normal weight (BMI) but higher risk WC perceived their weight as about right whereas just under half of men who were overweight (BMI) but lower risk WC perceived their weight as about right. For women, a much higher proportion recognized their weight status as overweight when only BMI was elevated compared to when only WC indicated higher risk.

DISCUSSION

Adults in our sample showed reasonable accuracy in weight perception. Gender differences reveal that women were more accurate than men in identifying themselves as overweight. Incongruence between weight status indicators was noted, indicating the importance of using both BMI and waist circumference as health status measures.

Cohorts and consortia conference: a summary report (Banff, Canada, June 17-19, 2009)

Epidemiologic studies have adapted to the genomics era by forming large international consortia to overcome issues of large data volume and small sample size. Whereas both cohort and well-conducted case-control studies can inform disease risk from genetic susceptibility, cohort studies offer the additional advantages of assessing lifestyle and environmental exposure-disease time sequences often over a life course. Consortium involvement poses several logistical and ethical issues to investigators, some of which are unique to cohort studies, including the challenge to harmonize prospectively collected lifestyle and environmental exposures validly across individual studies. An open forum to discuss the opportunities and challenges of large-scale cohorts and their consortia was held in June 2009 in Banff, Canada, and is summarized in this report.