Lecture 4 Flashcards
Lecture 4:
What are Epidemiological Studies?
Population based studies that examine cohorts over time
- control for confounding factors & examine relationships between variables of interest (eg; PA & cancer diagnosis)
Lecture 4:
What are confounding factors?
Something else that may v contribute to cancer risk
- eg; smoking - people who smoke don’t typically exercise so it could be another contributing factor to PA & cancer diagnoses
Lecture 4:
What is a case control study?
Have a group of “cases” & matched “controls”
- compare cases & controls on different
Lecture 4:
What are Observational Epidemiological Studies?
Follows large group of people to see who develops an outcome of interest
- compare differences between groups (eg; diff in PA b/with those w vs with/out cancer diagnoses)
*examines everything, not just one specific thing
*seize of study so large means more reliable
Lecture 4:
What are 2 things that Epidemiological Studies Examine?
1.) Domain of PA
2.) Volume of PA
Lecture 4:
When discussing Domains of PA, what are the 4 Domains?
- describe each
1.) Occupational - working & PA you get @ work (nurses/labourers vs truck drivers)
2.) Recreational - PA done for fitness (sports, gym, …)
3.) Household - activity in & around house (eg; chores - vacuuming, shovelling, yard work, etc)
4.) Transport Activity - movement to get to & from places (walking to class, active transportation, etc)
Lecture 4:
When discussing Volume of PA, what are the 3 volumes?
1.) Frequency - how much (how many days/times)
2.) Duration - amount of time you do the exercise for
3.) Intensity - light, moderate, vigorous, etc
Lecture 4:
What is sedentary behaviour?
Walking activities with an energy expenditure of under 1.5 METS
Lecture 4:
What are some examples of sedentary behaviour?
Driving, sitting on couch, n being in class/doing school, etc
Lecture 4:
Is high sedentary behaviour always equal to low PA?
No, as you can still be very active but if you sit the rest of the day/time you’re sedentary
- sedentary behaviour matters as its linked to heart diseases 7 other factors similar to Physical inactivity
Lecture 4:
What percentage of individuals spend their awake time sedentary?
High proportion, around 55% spend majority of their awake time sedentary
Lecture 4:
What are some points on Colon cancer prevention & PA?
- 21-27% reduced risk when physically active
- sedentary behaviour increases risk 28-44%
- occupational activity = same protection as recreational activity
- 30-60min/day of moderate to vigorous PA = most beneficial
Lecture 4:
What are some points on Breast cancer prevention & PA?
- 19-27% reduced risk when physically active (dose response)
- recreational/household activities = most beneficial
- recommended 4-7hrs/week moderate to vigorous activity
Lecture 4:
What are some points on Endometrial (uterine lining) cancer prevention & PA?
- risk reduced 19-29% (independent of adiposity/obese)
- 28-36% increased risk for sedentary behaviour (5hr+ sitting/day)
- recommended 1hr/day moderate-intensity PA
Lecture 4:
What are some points on Prostate cancer prevention & PA?
- 3-13% reduced risk when physically active
- limited evidence on PA & preventions
- benefit may be better in advanced prostate cancer
- many men die with undiagnosed prostate cancer (bc slow growing & latent)
Lecture 4:
What are some points on Lung cancer prevention & PA?
- 27-28% reduced risk when physically active (strongest effect in recreational PA)
- 21-27% increased risk when sedentary
- confounding variables & moderate/limited evidence)
Lecture 4:
What is the Purpose of the California Teachers Study?
Examine the amount & intensity of of PA & breast cancer risk reduction (in situ vs invasive)
Letcure 4:
What is the difference between invasive cancer & in situ cancer?
Invasive = stages 1-4 & can travel anywhere
In Situ = more superficial & not as bad as only one layer of cancerous cells exists
Lecture 4:
Who were the participants in the California Teachers Study?
- how many people
- gender & age
- type of cancer
110,599 women ages 20-79 years with no history of cancer
- studied from 1995/96 to 2002
- 2649 received diagnosis for invasive BC & 593 with in situ BC
- collected info on PA in HS, recently, & time between
Lecture 4:
So what was found during the California Teachers Study?
There is a dose response relationship between PA & invasive & in situ breast cancer risks
- more PA done = the better (to a certain point)
- found that strenuous activity over lifetime was best for decreasing BC risk
Lecture 4:
They also studied colon cancer risks in the California Teachers study; how many received a diagnosis?
395 of the 110,599 women studied were diagnosed with invasive colon cancer
*found that PA did reduce the risk of colon cancer
Lecture 4:
What are the big 4 common types of cancers?
1.) Breast
2.) Prostate
3.) Colon
4.) Lung
