NS 3030 Quiz 3 with Complete Solutions
what doe AHS-2 author suggest could be a cause of the difference in deaths between groups?
lower saturated fats
-higher fiber consumption
Comparison British veg. and US adventist vegetarians eat somewhat differently
-US consume more fiver and more vitamin C than oxford
-mean vitamin C in EPIC oxford vegans was 135 mg/d
compared with 224 mg/day in men and 250 mg/day in women but mean = 500
EPIC mortality follow up mortality of both the vegetarians and non-vegetariansi n this
study is low (half) compared with national rates (comparing vegetarians to a healthy cohort)
-6 year follow up
-vegan/veg group showed about a 19% reduction in all caue mortality
-all cause not significant b/c 1 is in the confidence interval
-19% reduction in mortality not significant (But could be in more years to follow up)
,-
What can you do with a non significant trend? see if it could be biologically important
What did the EPIC authors conclude about the 19% decrease previous studies have
yielded estimates that the risk of IHD is reduced by 6%/1unit reduction in BMI (19) and by
about 1% for each 1% reduction in serum LDL cholesterol
-the 19% difference found in this study is relatively close to the expected reduction based on
difference in BMI and serum cholesterol
-if veg have a 1 pt lower BMI, then they have 6% lower risk of death from IHD + 12% lower
serum cholesterol, so 12% lower risk of IHD
-add these together --> value of 18% decrease risk in death from IHD this is very close to the
19% found in the study
three risk factors associated with vegetarian dietary patterns 1. BMI
2. serum cholesterol
3. blood pressure
,meta analysis of AHS and EPIC studies -there is not a significant reduction in all cause
mortality for the AHS or the EPIC study
-no benefit on all cause mortality from this data
-AHS 40% significant decrease in IHD mortality
-EPIC 16% significant decrease in IHD mortality
-if put together there is about a 30% decrease in death from heart disease from IHD
Conclusion meta analysis AHS-2 and EPIC -veg. diet associated with sig. reduction in
IHD
-reported benefit most apparent in AHS cohort
-not a group that is derived from the general population (AHS decrease risk may make up most
of data)
-group that shows the greatest effect may not be generalizable
Difference in weight/bmi with veg. vs. non veg 20 lb
10 kg
2 BMI units
, Oxford health study and BMI 1.13 point lower BMI for non-meat eaters
-adjust for age alone and it's 1.13
-adjust for animal fat and get 1.01 (so changes b/c anamial fat is a confounder that contributes to
BMI difference, this is an 11% reduction with this adjustment
-exercise (no impact)
-dietary fibers --> 18% influence
-alcohol 15%
-so from 1.12 --> 0.73 when adjustments are made
BMI confounders in veg. diet 1. age
2. animal fat
3. dietary fibers
4. alcohol
-together there is a 36% reduction therefore, 36% of the 1.13 BMI unit difference between veg
and non veg is attributed to theses 3 factors
for a 5 unit increase in BMI units, what is the increased risk of IHD death? 40% increase
(for 60-69 year olds)
what doe AHS-2 author suggest could be a cause of the difference in deaths between groups?
lower saturated fats
-higher fiber consumption
Comparison British veg. and US adventist vegetarians eat somewhat differently
-US consume more fiver and more vitamin C than oxford
-mean vitamin C in EPIC oxford vegans was 135 mg/d
compared with 224 mg/day in men and 250 mg/day in women but mean = 500
EPIC mortality follow up mortality of both the vegetarians and non-vegetariansi n this
study is low (half) compared with national rates (comparing vegetarians to a healthy cohort)
-6 year follow up
-vegan/veg group showed about a 19% reduction in all caue mortality
-all cause not significant b/c 1 is in the confidence interval
-19% reduction in mortality not significant (But could be in more years to follow up)
,-
What can you do with a non significant trend? see if it could be biologically important
What did the EPIC authors conclude about the 19% decrease previous studies have
yielded estimates that the risk of IHD is reduced by 6%/1unit reduction in BMI (19) and by
about 1% for each 1% reduction in serum LDL cholesterol
-the 19% difference found in this study is relatively close to the expected reduction based on
difference in BMI and serum cholesterol
-if veg have a 1 pt lower BMI, then they have 6% lower risk of death from IHD + 12% lower
serum cholesterol, so 12% lower risk of IHD
-add these together --> value of 18% decrease risk in death from IHD this is very close to the
19% found in the study
three risk factors associated with vegetarian dietary patterns 1. BMI
2. serum cholesterol
3. blood pressure
,meta analysis of AHS and EPIC studies -there is not a significant reduction in all cause
mortality for the AHS or the EPIC study
-no benefit on all cause mortality from this data
-AHS 40% significant decrease in IHD mortality
-EPIC 16% significant decrease in IHD mortality
-if put together there is about a 30% decrease in death from heart disease from IHD
Conclusion meta analysis AHS-2 and EPIC -veg. diet associated with sig. reduction in
IHD
-reported benefit most apparent in AHS cohort
-not a group that is derived from the general population (AHS decrease risk may make up most
of data)
-group that shows the greatest effect may not be generalizable
Difference in weight/bmi with veg. vs. non veg 20 lb
10 kg
2 BMI units
, Oxford health study and BMI 1.13 point lower BMI for non-meat eaters
-adjust for age alone and it's 1.13
-adjust for animal fat and get 1.01 (so changes b/c anamial fat is a confounder that contributes to
BMI difference, this is an 11% reduction with this adjustment
-exercise (no impact)
-dietary fibers --> 18% influence
-alcohol 15%
-so from 1.12 --> 0.73 when adjustments are made
BMI confounders in veg. diet 1. age
2. animal fat
3. dietary fibers
4. alcohol
-together there is a 36% reduction therefore, 36% of the 1.13 BMI unit difference between veg
and non veg is attributed to theses 3 factors
for a 5 unit increase in BMI units, what is the increased risk of IHD death? 40% increase
(for 60-69 year olds)
