Risks of Cardiovascular Disease Powerpoint

AS level lesson on CVD and risk factors

1. Risks of cardiovascular disease (CVD)

2. Learning outcomes • explain the causes and consequences of cardiovascular disease   • analyse and interpret data associated with specific risk factors and the incidence of cardiovascular disease   • recognise correlations and causal relationships

3. Starter: Discussion Would you want to know if you were at risk of a certain disease? Why/why not?

4. Task Using the fact sheets around the room fill in your table of the risk factors of CVD. Then describe you think the risk could be prevented. NB: there is no card for atherosclerosis as you should know this already. Extra challenge: Explain which factors you feel pose the biggest risk of getting CVD. LO: To describe the factors that increase the risk of CVD. To analyse how risks can be reduced

5. Questions 1. Looking at the table, what happens to your risk of developing cardiovascular disease as you get older? Extra challenge: Does this mean, that at your age you need not worry? Age/ years Female Male Heart attack stroke Heart attack stroke 16 - 44 1 45 - 64 18 5 18 8 65 - 74 51 12 84 17 75 and over 67 28 83 54 Rates per 1000 population reporting longstanding diseases of the circulatory system by sex and age, 2004, Great Britain LO: To evaluate the effect of age by interpreting qualitative data.

6. 3 . Do these data suggest that males and females face the same risk of cardiovascular disease? Age/ years Female deaths Male deaths Under 1 13 22 1-4 8 12 5-14 19 29 15-24 65 96 25-34 170 341 35-44 552 1343 45-54 1362 3930 55-64 3541 9330 65-74 11 304 19 783 75-84 35 958 35 607 85+ 46 470 20 816 Totals 99 462 91 309 Mortality data from diseases of the circulatory system for England and Wales 2004 LO: To interpret quantitative data on cardiovascular disease.

7. Exam style question Explain how each of these risk factors can influence the onset of CHD: High cholesterol Smoking Diet (6 marks) Read your partners answers: -WWW -EBI Sign and date They then should fill in an INT

8. Resources

9. Smoking as a risk factor Smoking Reduces levels of HDLs Carbon monoxide increases deposition of cholesterol in atheroma formation Increases heart rate + causes vasoconstriction to increase blood pressure i ncreases risk of damage to lining of arteries increases risk of atherosclerosis Contents in smoke (e.g. free radicals) which get into blood stream can damage endothelium lining of blood vessels

10. More on smoking Carbon monoxide combines irreversibly with haemoglobin to produce carboxyhaemoglobin which cannot carry oxygen so oxygen-carrying capacity of blood reduced If blood flow is reduced due to atherosclerosis tissues get even less oxygen which can increase risk of cell damage/death Nicotine also increases stickiness of platelets so increasing risk of blood clots, especially in the coronary arteries  increased risk of CHD

11. Salt In general terms our diet contains too much salt, especially in all the processed foods we eat. Just look at the food labels! Only 6g per day recommended (most people normally eat > 10 g per day!) A high salt diet causes the kidneys to retain too much water so higher fluid content in the blood increases blood volume which increases blood pressure which can increase risk of CVD

12. Exercise Exercise improves coronary circulation, which decreases the risk of CVD. Exercise also increases HDL levels which helps to lower bad cholesterol (LDL’S). Lower levels of exercise make the heart inefficient, as the cardiac output is reduced. The heart rate increases and the artery walls become less elastic.

13. Vitamins as antioxidants Free radicals – highly reactive chemicals (atom with an unpaired electron) produced by some normal metabolic reactions in the body or in reactions that breakdown toxins (including those found in cigarette smoke). Act as oxidising agents – can damage DNA, proteins and other molecules Damage is cumulative over time, so associated with ageing Oxidised LDLs more readily taken up by white blood cells involved in atherosclerosis, hence CHD Antioxidants help prevent damage caused by free radicals (provide H atoms to pair up with the unpaired electron) Good sources of dietary antioxidants include: Vitamin C e.g. from citrus fruits, broccoli, tomatoes Vitamin E e.g. from wholegrain cereals, bread, peanuts, fish Beta-carotene (used to make vitamin A) e.g. carrots, sweet potatoes, spinach, peaches, mangoes

14. Obesity Obesity defined as having a BMI > 30 BMI = body mass index = body mass in kg / (height in m) 2 Increases risk of CHD Blood pressure increases Blood LDL cholesterol level increases which increases the risk of atheroma and atherosclerosis [Blood supply in coronary arteries blocked; reduced blood supply reduces supply of oxygen  can lead to damage or death to heart muscle cells  heart unable to beat properly = heart attack] Increases risk of type II diabetes which also increases risk of CHD as elevated glucose levels cause high blood pressure.

15. High density lipoproteins = HDLs (unsaturated fats) HDLs are ‘good cholesterol’ transport cholesterol absorbed from food to liver to be broken down (some excreted in bile) so get rid of cholesterol so lowers blood cholesterol so prevent cholesterol deposition in artery walls so prevent atherosclerosis

16. Low density lipoproteins = LDLs (saturated fats) LDLs are ‘bad’ cholesterol circulate in bloodstream not taken up by body cells so not removed so blood cholesterol levels high this get deposited in artery walls  atheroma [ leading to atherosclerosis which narrows the arteries reducing the blood supply which increases the risks of CHD ]

17. Alcohol Alcohol decreases the blood flow to the muscles (including the heart), this can lead to coronary heart disease. It increases blood pressure by constricting the arteries. It also has an effect on the rhythm on the heart which can lead to arrhythmia. It is also calorie rich and can lead to obesity.

18. Age and gender Women have naturally higher HDL levels reducing their risk of atheroma. This is due to higher oestrogen levels. Oestrogen also increases the blood flow to the muscles (including the heart). Arteries become less elastic with age which can increase blood pressure and the risk of blood vessel damage.

19. Genetics Some alleles increase the risk of CVD, these are inherited from family members. These alleles may cause a variety of problems e.g. valve weakness, high blood pressure, high LDL and cholesterol levels. Some can be beneficial e.g. high HDL levels which helps lower cholesterol.

20. Stress This causes the release of adrenaline which increases the heart rate and constricts the arteries. People with stressful jobs (the 3 most stressful statistically are: miners, emergency services and teachers) are most at risk.