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Flashcards in lecture 6: cardiovascular risk factors Deck (26)
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1
Q

What is cardiovascular (CV) disease?

A
  • heart attack
    • blockage/atherosclerosis of coronary arteries
    • defined in terms of the death of the muscle of the heart
    • no collateral arteries that can provide blood when things go wrong
    • lots of collateral arteries in the brain
    • when heart muscle dies it cannot recover
  • stroke
    • occurs if there is a problem with blood supply to the brain
    • blockage → tissue starved of oxygen
    • haemorrhage → blood vessel breaking under pressure and leaking blood into the surrounding tissue
    • kills the cells in the brain
    • unable to reproduce to make up for what’s lost
2
Q

What are established CVD risk factors?

A
  • age
    • even leading a healthy life the integrity of blood vessels lessens
    • the processes of atherosclerosis are more likely as you get old
  • blood pressure
    • adding extra stress to vessels and heart
  • cholesterol
    • higher the level the greater the risk
    • contributes to development of athersclerosis
  • body mass index
    • plugs into BP and cholesterol
  • smoking
  • diabetes

established risk factors because they have been shown to be associated with cardiovascular disease

3
Q

What are other CVD risk factors?

A
  • left ventricular size
    • even with no other risk factors people with naturally big hearts had increased risk of dying of CVD
  • fibrinogen (clotting factors)
    • levels of clotting factors perhaps a predisposition of developing clots
  • other lipids
    • beyond cholesterols e.g. apoplipoproteins etc
  • homocysteine
    • losing credibility as a major risk factor
    • related to clotting and other factors in a way
  • things that are associated with CVD but aren’t established as major risk factors
4
Q

What is true of CVD risk factors?

A
  • risk factors tend to aggregate
  • weight gain promotes major CVD traits
5
Q

What is the single most important risk factor in CVD?

A
  • Age
  • 80% of CVD occur in people greater than 65 years
6
Q

What is the relationship between sex and CVD?

A
  • men die earlier and more frequently from CVD
  • women are “protected” before the menopause
  • even after menopause male risk is higher than female
  • hormone therapy in the menopause does not reduce CVD
    • now limited to the perimenopausal period to help women cope with symptoms e.g. flushes
7
Q

What is the contribution of family history to CVD?

A
  • CVD in a first degree relative increases risk 4-fold
  • genes and environment
8
Q

Are there CVD genes?

A
  • individual genetic variants explain small amounts of risk
  • must be polygenic
9
Q

How do lipids contribute to CVD?

A
  • cholesterol
    • LDL, VLDL – bad cholesterol
      • the way the cholesterol is packaged up with proteins
      • they are involved with transporting cholesterol and other lipids from the liver out to the peripheral tissues e.g. muscles (good) but sometimes end up in your arteries
      • high levels → increased risk of atherosclerosis
    • HDL – good cholesterol
      • involved in reverse transport of cholesterol
      • takes cholesterol from the peripheral tissues back to the liver
      • (simplistic)
      • marry with the evidence
      • increased exercise leads to increased HDL
      • also alcohol in moderation
  • triacylglycerol
    • associated with metabolic syndrome in particular
    • tend to go up if your weight goes up
    • associated with increased risk but not as strongly as cholesterol
10
Q

What is the contribution of being overweight to CVD?

A
  • especially central adiposity
  • high BP
  • high lipids
  • insulin resistance
11
Q

What is the contribution of alcohol to CVD?

A
  • two units per day → best amount of alcohol you can drink to lower your risk of CVD
  • if you drink with less → higher risk
  • drink more → higher risk
  • J curve
  • HDL cholesterol is one explanation
12
Q

What is the contribution of stress to CVD?

A
  • unproven but popular explanation
  • paper that linked these was based on the Chicago Heart Study in which type A personalities were implicated but when they actually followed study all the way through it was the type B personalities who died more frequently of CVD
  • how do you measure stress?
13
Q

What are graded risk effects?

A
  • boxes of varying sizes reflecting the number of people that fit that box
  • see that the people with the highest blood pressures have the highest risk
  • (y axis is logarithmic, doubling of risks)
  • even having a normal blood pressure is associated with a higher risk of CVD than someone who has low blood pressure i.e. even an average blood pressure carries a risk
  • bigger jumps in risk with BPs above normal but still an important consideration
  • a risk associated with every increment in blood pressure across a community
  • relative risk vs absolute risk → a lot more people in the middle boxes, a lot more dying, so actually get more deaths with that particular group
  • most of the people who die from CVD as a result of blood pressure are people with relatively average BPs
  • concept that it’s all very well for doctors and patients to get together, but the real issue is getting people with even average blood pressure to get theirs lower
  • this is the basis of the population public health approach
  • medical approach is aimed at finding people with the highest risk and dealing with that individually while the other is aimed at targeting people/large populations with average risk and dealing with that
14
Q

What do public health measures have to be?

A
  • safe
  • cheap
  • effective
  • i.e. cannot just be put drugs in the tap water
15
Q

What is the CVD population paradox?

A
  • more deaths occur in the large number at modest risk than in the small number at high risk
16
Q

What are approaches to reducing CV disease?

A
  • public health prevention
    • everybody
  • treatment
    • patients
17
Q

What are public health approaches to reducing CVD?

A
  • better diet
  • more exercise
18
Q

What are treatment approaches to reducing CVD?

A
  • non-pharmacological
    • individualised public health campaign
    • fix your diet and exercise
    • lifestyle etc
    • come back and we will check out cholesterol/BP again etc
  • pharmacological
    • drugs to treat these things are usually forever
19
Q

When to treat?

A
  • when the risk of treatment is less than the benefit of treatment
  • take that for granted
20
Q

What is high CV risk?

A
  • more than 15% event risk over 5 years (NHF)
  • systolic more than 180 mmHg
  • diastolic more than 11 mmHg
  • systolic greater than 160 mmHg and diastolic less than 70mmHg (reflection of stiffness of vessels)
  • but risk isn’t all about blood pressure
  • so if systolic is greater than 140mmHg or Diastolic is greater than 90mmHg with associated conditions (diabetes, existing CV or renal disease) or high CV risk
21
Q

What are standard risk factors?

A
  • age
  • sex
  • systolic pressure
  • total:HDL cholesterol ratio
  • smoking
22
Q

What is end organ damage?

A
  • another way to measure risk
  • e.g.
  • LV hypertrophy
  • Low eGFR*
  • microalbuminuria *
  • pulse wave veolicty
  • intima-media thickness
  • tests that are starting to appear to measure the overall risk etc
23
Q

How is CVD a modern epidemic?

A
  • emerging as a major cause of death in developing countries
  • rising in central and Eastern Europe and big asian countries
  • falling in North America and Australasia
  • falling from low levels in Japan
24
Q

What is the relationship between CVD and society?

A
  • important factors
    • diet
    • cigarette smoking
    • others
  • diet probably number one: look at japan great diet but lots of smoking
25
Q

What is a possible explanation for low CVD in Japan?

A
  • medical care
    • low consumer
  • smoking
    • high (2/3 of men)
  • nutrition
    • dietary fat is less than 25% of japanese diet (UK 42%)
    • PS:S ~ 1.1 (UK 0.4)
26
Q

What is the french paradox?

A
  • love pastries, dairy etc
  • also love smoking
  • what is going on?
  • don’t have a japanese diet
  • no one knows
  • market the concept that it is french red wine
  • mysteries about populations are uncertain

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