Canadian Longitudinal Study on Aging: Platform for studying the epidemiology of the COVID-19 pandemic in aging populations [CLSA, study data contributed to the CITF Databank]

They also aimed to better understand the symptoms, risk factors, and impacts of COVID-19 through questionnaires.

Methods

The CLSA cohort study enrolled participants aged 45-85 across Canada via random digit dialling. Participants in the tracking cohort comprised a representative sample of Canadians, who completed cognitive tests and answered questionnaires via telephone interview at baseline and at two follow-ups. Those in the comprehensive cohort were selected from a random sample of Canadians, and participated in an at-home physical exam, answered questionnaires, completed cognitive tests, and provided blood and urine samples at baseline and two follow-ups.

For participants aged 55-80 in this cohort, they completed repeated cognitive testing and brain scans for brain health surveillance. Participants in all cohorts provided a blood sample for COVID-19 antibody testing and completed a COVID-19 questionnaire. Each participant was contacted every 3 years and was followed for at least 20 years or until death.

Summary of the contributed data: The datasets include 19,334 participants who completed baseline surveys between October 2020 and August 2021. 23% of participants gave one or more blood samples between October 2020 and July 2021 for analysis. A total of 4,365 samples were collected. Variables include data in the following areas of information: demographics (age, gender, race-ethnicity and indigeneity, province, household composition, education), general health (smokes, chronic conditions, height and weight, flu vaccine), exposure risk factors (occupation, travel history, adherence to COVID-19 public health guidelines), COVID infection history (positive tests, symptoms, hospitalizations), SARS-CoV-2 vaccination, and qualitative serology (antibodies against SARS-CoV-2 nucleocapsid and spike proteins).