Lecture 18 : Heart Disease 1 Factors Overview

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Lecture 18 Heart Disease (1) FactorsOverview

• TERMINOLOGY
• PREVALENCE
• FACTORS

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Terminology

• There are different types of heart disease (e.g.
  congenital heart disease), but most deaths are
  caused by a heart attack (myocardial infarction
  or coronary thrombosis).
• Atheroma refers to the silting-up of the arteries
  by deposits of fat.
• Arterioslerosis refers to a hardening of the
  arteries.
• Acute episodes are often triggered by a
  thrombosis - i.e. a blockage caused by a blood
  clot or a breakaway piece of plaque getting stuck
  in a narrowed artery
• If the blockage occurs in the coronary artery,
  the result is a myocardial infarction. If it
  occurs in the brain, the result is a stroke.

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Prevalence

• Ireland has one of the highest rates of heart
  disease mortality in the world.
• Heart disease accounts for almost one third of
  all deaths, and diseases of the circulatory
  system as a whole acount for almost one half od
  all deaths.
• Deaths from heart disease have been declining
  since the 1980s.

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Factors (1)

• Genetics. It is difficult to distinguish nature
  from nuture, but higher risks seem to run in
  families.
• Tobacco. Cigarettes significantly increase the
  risks of a heart attack and reduce the likelihood
  of survival. Nicotine damages platelets,
  increases risks of clotting, and interferes with
  electrical activity of the heart. Carbon monoxide
  reduces oxygen carrying capacity of the blood.
• Hypertension (high blood pressure) is a
  recognised risk factor.

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Factors (2)

• Obesity. Obesity is a recognised risk factor.
• Stress. Heart attacks are frequently observed
  after stressful life events, but the role of
  stress is still unclear.
• Personality type. Type A (up-tight)
  personalities have a thigher risk than type B
  (laid-back) personalities.
• Exercise. Regular exercise is believed to reduce
  the risks.

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Factors (3)

• Diet
• Animal (saturated) fats increase risks
• Sugars and carbohydrates in large quantities are
  believed to increase risks
• Dietary fibre is believed to reduce risks (partly
  by making it easier to reduce total food intake)
• Too much salt is generally believed to be bad for
  you (although it is essential for health in the
  correct quantities)
• Alcohol. High alcohol consumption increases
  riskes, but moderate consumption may actually be
  beneficial.

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Factors (4)

• Water Hardness. Soft water is thought to carry a
  higher risk than hard water, but the
  relationships may be spurious.
• Air pollution. Acute episodes are more numerous
  in periods of high air pollution, but it is less
  clear whether air pollution causes heart attacks
  or triggers off attacks in people who are
  susceptible for other reasons.