PHYS30001 Lecture Notes - Lecture 1: Adipose Tissue, French Paradox, Cardiovascular Disease
Coronary heart disease = obstruction of coronary arteries (atherosclerosis, clotting) - heart
attack, angina (restriction of blood flow but not enough to permanently damage). Leads to 1 in
3 deaths
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Age: disease of the middle aged/elderly due to wear and tear on heart
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cholesterol
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blood pressure
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body mass index
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Smoking (very strong factor)
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Diabetes (can be treated and controlled)
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All are causative (apart from age) and reversing these factors can reduce risk
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Established CHD risk factors
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left ventricular size (strongest risk factor after age): reflects blood pressure, body
weight, diabetes - associated with other risk factors that it represents
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fibrinogen (clotting factors): high levels increase risk
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other lipids
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homocysteine
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Not established, i.e. reversing these does not reverse the risk
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Other CHD risk factors
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weight gain promotes major CHD traits
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e.g. in metabolic syndrome
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Risk factors tend to aggregate
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age is the single most important risk factor
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80% of CHD occur in people > 65 years
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Age & CHD
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men die earlier and more frequently from CHD
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women are “protected” before menopause
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even after menopause male risk is higher than female
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hormone therapy in the menopause does not reduce CHD, and even worsened their risk
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Sex & CHD
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Adjustments: rates of CHD are usually expressed after adjustments for the effects of age & sex
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CHD in a first degree relative increases risk 4-fold
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genes & environment are both shared in families, so account for the increased risk
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Family history
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Look for genes shared by siblings with CHD
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Insulin receptor substrate-1 linked to:
CHD genes
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Risk factors
1 Risk factors for coronary disease
Monday, 27 July 2015
12:54 PM
Cardio Page 1
insulin resistance (leads to diabetes)
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hypertension
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impaired endothelial function - atherosclerosis
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high TAGs
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coronary artery disease
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Insulin receptor substrate-1 linked to:
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LDL, VLDL - bad cholesterol: takes lipids from liver to periphery, leading to plaques
in arteries
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HDL - good cholesterol: takes lipids around the body back to the liver (clears out
arteries). Higher levels associated with lower CHD risk
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cholesterol
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triacylglycerol
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Lipids
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especially central adiposity - fat on abdomen has more serious metabolic consequences
than fat on thighs
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high BP
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high lipids
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insulin resistance
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Overweight (metabolic syndrome)
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Stress: unproven but popular explanation. Hard to measure, subjective. Conjecture about
acute vs chronic underlying stress
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Alcohol: Two units per day reduces risk, doesn't matter what kind of alcohol
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x-axis: e.g. blood pressure or cholesterol level
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y-axis: individual's risk is graded with increasing level of risk factor (no threshold of no
risk to risk)
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Graded risk effects
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CHD mortality - average across population
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Cardio Page 2
Document Summary
Coronary heart disease = obstruction of coronary arteries (atherosclerosis, clotting) - heart attack, angina (restriction of blood flow but not enough to permanently damage). Age: disease of the middle aged/elderly due to wear and tear on heart cholesterol blood pressure body mass index. All are causative (apart from age) and reversing these factors can reduce risk. Other chd risk factors left ventricular size (strongest risk factor after age): reflects blood pressure, body weight, diabetes - associated with other risk factors that it represents fibrinogen (clotting factors): high levels increase risk other lipids homocysteine. Not established, i. e. reversing these does not reverse the risk. Risk factors tend to aggregate weight gain promotes major chd traits e. g. in metabolic syndrome. Sex & chd age is the single most important risk factor. Adjustments: rates of chd are usually expressed after adjustments for the effects of age & sex.
