Covert vascular brain injury and cognitive dysfunction among Chinese adults living in Canada and China
The researchers examined how country of residence influences covert cerebrovascular disease (VBI) and cognitive dysfunction among Chinese adults living in Canada and China. The study compared Chinese adults in Canada and China. They found that people in Canada had a lower prevalence of covert VBI and cognitive dysfunction than those living in China, even though both groups shared the same ethnicity. Living in China was associated with a much higher risk of covert VBI and lower cognitive function, although the link between cognitive dysfunction and country of residence was explained by education and traditional cerebrovascular risk factors, such as blood pressure and cholesterol.
Effects of gene dosage on cognitive ability: A function-based association study across brain and non-brain processes
The researchers assessed the relationship between copy-number variants (CNVs) and cognitive ability using data from six cohorts, including the CARTaGENE cohort. They performed a genome-wide association study (GWAS) with 258,292 individuals, identifying a duplication at 2q12.3 associated with higher cognitive performance. A functional-burden analysis was developed to examine the association between cognition and CNVs disrupting 6,502 gene sets defined across various biological tissues, cell types, and ontologies. Among these, 864 gene sets were linked to cognition, with the effect sizes of deletions and duplications negatively correlated. Deletions affected subcortical regions and postsynaptic functions, while duplications impacted the cerebral cortex and presynaptic functions.
Association of lifetime lactation and characteristics of menopause: a longitudinal cohort study
The researchers used survey data on 19,783 parous women aged 40 to 65 years at enrollment in the Alberta’s Tomorrow Project to investigate the association between lifetime duration of lactation and the timing and type of menopause in midlife women. They found that in a dose-response manner, longer lactation was associated with reduced risk of natural menopause before age 50, surgical menopause before age 55, and indeterminate menopause before age 50. Longer lactation was associated with lower odds of surgical and indeterminate menopause, compared to natural menopause.
Exposure to air pollutants and subclinical carotid atherosclerosis measured by magnetic resonance imaging: A cross-sectional analysis
The researchers examined how long-term exposure to air pollution affects early signs of heart disease. They used data to explore whether low levels of air pollutants are linked to the thickening of artery walls. The study included 6,645 adults from five Canadian provinces and estimated their exposure to nitrogen dioxide (NO₂), ozone (O₃), and fine particulate matter (PM2.5) over several years. Using MRI scans to measure carotid artery wall thickness, the researchers found mixed results. Higher levels of ozone were linked to thicker artery walls, suggesting a potential negative effect, while higher nitrogen dioxide levels were associated with thinner artery walls, a finding that requires further investigation.
Association of parity with the timing and type of menopause: A longitudinal cohort study
The study aimed to determine the time-varying association between parity and timing of natural menopause, surgical menopause, and premenopausal hysterectomy among 23,728 women aged 40-65 years at enrollment in the Alberta’s Tomorrow Project cohort study. The researchers found that overall, natural menopause was most common, then premenopausal hysterectomy and surgical menopause. The risk of natural menopause before age 50 was higher for women with 0 or 1 birth, while the risk was similar for those with 3 or more births compared to those with 2 births. Elevated risks of surgical menopause before age 45 for women with 0 or 1 birth were reduced after excluding those with a history of infertility or recurrent pregnancy loss, and the risk decreased over time for women with 3 or more births. Additionally, the risk of premenopausal hysterectomy before age 50 was lower for women with 0 births but increased after age 40 for those with 3 or more births.
Cohort profile: the CARTaGENE Cohort Nutrition Study (Quebec, Canada)
The researchers aimed to address emerging nutritional epidemiological research questions, using data from the CARTaGENE cohort. Dietary information was collected making it a rich resource for the exploration of diet in the etiology of many health outcomes. They found that dietary intake and quality varied among participants but generally met recommended nutrient levels. Along with other findings, the Canadian Healthy Eating Index 2005 (C-HEI) scores were higher among never smokers, those with higher education, and those with more physical activity compared to current smokers, less than high school education, and those with lower physical activity.
Early Changes in Tumor-Naive Cell-Free Methylomes and Fragmentomes Predict Outcomes in Pembrolizumab-Treated Solid Tumors
The researchers investigated pharmacodynamic biomarkers of response to pembrolizumab in 106 patients with advanced solid tumors. Researchers analyzed genome-wide methylation and fragment-length profiles using cfMeDIP-seq in 204 plasma samples from 87 patients. Two cohorts of normal control cfMeDIP-seq data, including 72 healthy women from the Ontario Health Study, were used for comparison. CSM and FLS are strongly correlated with tumor-informed ctDNA levels. The study found that early kinetics of cancer-specific methylation (CSM) predicted overall survival and progression-free survival, independent of tumor type, PD-L1, and tumor mutation burden. The researchers’ tumor-naïve mutation-agnostic ctDNA approach integrating methylomics and fragmentomics could predict outcomes in patients treated with pembrolizumab.
The mediating role of health behaviors in the association between depression, anxiety and cancer incidence: An individual participant data meta-analysis
Researchers investigated how various health behaviors might mediate the relationships between depression, anxiety, and the onset of different types of cancer. They conducted individual participant data meta-analyses using participants from 18 cohorts from the Psychosocial Factors and Cancer Incidence consortium.The cohorts analyzed included the Atlantic Partnership for Tomorrow’s Health, Ontario Health Study, and CARTaGENE. The findings suggested that smoking serves as a mediating factor that connects depression and anxiety with lung cancer and other cancers related to smoking.
Psychosocial factors, health behaviors and risk of cancer incidence: Testing interaction and effect modification in an individual participant data meta-analysis
Researchers determined whether psychosocial factors interact with or modify the effects of health behaviors, such as smoking and alcohol use, in relation to cancer incidence. Data were used from 22 cohorts, including the Ontario Health Study, Atlantic Partnership for Tomorrow’s Health, and CARTaGENE. After exploring 744 combinations of psychosocial factors, the researchers found no evidence that psychosocial factors interacted with or modified health behaviors related to cancer incidence.
The evolution of SARS-CoV-2 seroprevalence in Canada: a time-series study, 2020-2023
This study used data from the COVID-19 Immunity Task Force, which includes CanPath data, to track the prevalence of SARS-CoV-2 antibodies in the Canadian population over the pre-vaccination period, the vaccine rollout, and the emergence of the Omicron variant. By March 2023, over three-quarters of the population had detectable antibodies, with the most substantial increases seen after the arrival of the Omicron variant. However, variations in immunity by age and geography highlight the importance of tailoring public health policies and clinical decisions to local patterns of population immunity, considering factors like potential antibody decline and the emergence of new variants that might evade immunity.