1. What is SAGE?
SAGE (the Study of Asthma, Genes, and the Environment), a longitudinal study, is a research project that involves following one group of people over a long period of time, anywhere from a few months to 30 years or more. Longitudinal studies are important in research because they allow researchers to track changes and trends in individual behavior, relationships, health and the development of disease over time. During a longitudinal study, the same people will be contacted several times over the course of years to see how they are doing.
A Cohort study involves following a group of people who share a particular issue (such as age, asthma, or allergies) over time. In the SAGE study, researchers followed all children enrolled.
The SAGE study also included a “Nested Case Control” group. This was a smaller group of children, selected from the larger group, with asthma and/or allergies. Extra research was done with this group to better understand factors what may contribute to their asthma.
2. How many children participated in the SAGE study?
The study started in 2002. Researchers sent letters to the parents of all children born in 1995 and still living in
. 13 980 families were invited to participate via a survey. Manitoba
3681 families completed and returned the survey. 11% had asthma, 5% had hay fever or food allergy. The rest (84%) did not have any allergic diseases. All families of children with asthma were invited to participate in the longitudinal study. Children without asthma were randomly selected and invited to participate in the study.
In all, 723 children agreed to participate. 246 with asthma and 477 without asthma.
3. How old were the children at the start of the study? How old are they now?
The children were 7 and 8 years old when the study began. The children are now 16 years old!
4. What did the researchers hope to learn?
The main objectives of the SAGE Study were:
i. to collect information about the home environment of children in
ii. to confirm the rate of asthma in Manitoban children and validate the tools used to diagnose asthma
iii. to understand the differences in children’s immune system that either predisposes or protects them from getting asthma
iv. to explore genes that may play a role in children developing asthma
v. to understand the relationship between genes and the environment in the development of asthma
5. Why did they ask us questions about the children's stage of puberty?
In early childhood, more boys have asthma than girls. By the late teen years however, more girls have asthma than boys. Questions about the stage of puberty were asked to try to better understand why asthma rates change for boys and girls in later childhood.
6. If an important health concern was discovered during the study, for example a very high blood pressure or other problem in the blood, did the research doctor tell the participants or were all results kept confidential?
Any health concerns noticed during tests were discussed with participants and their physician so that proper treatment and follow up could occur.
7. Are there plans to continue to follow this group of children?
Yes, we hope to continue to follow as many participants as we can. We have applied for funding from several health agencies to be able to do this.
8. Were there enough identical twins in the cohort to complete certain studies related to heredity?
No, the group of participants in the SAGE study did not have enough identical twins for this kind of study. One research group in
is studying a large group of identical twins. This will help us understand how much of asthma is genetic and how much is related to environment. Sweden
9. Researchers visited our homes and took dust samples and air samples to look for mold. Did they also take samples from the homes in the control group (the families whose children did not have asthma)?
Yes, samples were taken from all the homes. Data is still being analyzed to understand the role that mold plays in the development of asthma.
10. What other information did they learn?
Researchers learned a lot of information about asthma, but also some information about diet and nutrition, body image, family’s lifestyles and more. Follow our blog for a weekly summary of all that was learned!