Chronic Diseases (CVD and Cancer) Flashcards
(48 cards)
What is Chronic Disease?
Diseases of long duration & slow progression, cannot be transferred to other people.
Leading cause of mortality globally: 70% of deaths.
40 million deaths/year (31M in low/middle income countries), 15 million <70 years of age; >80% of premature deaths were in low/middle-income countries
4 major chronic diseases
Cardiovascular diseases (17.7M), cancers (8.8M), chronic respiratory diseases (3.9M), diabetes (1.6M)
Primary Risk Factors
Smoking, physical inactivity, obesity, unhealthy diet, high blood pressure, high cholesterol, high blood glucose
Leading risk factors globally (% of deaths):
HTEPO
High blood pressure (19%), tobacco (10%), elevated blood glucose (6%), physical inactivity (6%), obesity (5%).
9/10 Canadians have ≥1 risk factor:
Smoking, Physical inactivity, < recommended daily Vegetables/Fruit, Stress, Overweight/Obesity, High Blood Pressure, Diabetes. 2/5 have ≥3 risk factors.
Cardiovascular Disease (CVD)
Collective term for diseases of heart & blood vessels
1.6 million Canadians have heart disease or are living with the effects of a stroke
Affects 120,000 Canadians annually; heart disease & stroke are the leading cause of death
>$22 billion in direct ($7.6B) & indirect ($14.6B) health costs
Hospital care ($4B), Drug costs ($2.1B), Physician care ($1.5B)
Premature death ($9.3B), Long-term disability ($4.2B), Short-term disability ($1.2B).
Cardiovascular System
The system that circulates blood through the body: the heart + blood vessels
(O2)Arteries (O2)Heart
(DeOx)Veins (DeOx) Heart
(both) Capillaries (both) Tissues
Parts of the Heart
Fist-sized, 4 chambers
Right side: Pulmonary circulation
the system of transportation that shunts de-oxygenated blood from the heart to the lungs to be re-saturated with oxygen before being dispersed into the systemic circulation.
Left side: Systemic circulation
carries oxygenated blood from the left ventricle, through the arteries, to the capillaries in the tissues of the body.
How does the heart work
(1) Waste-carrying, 02-poor blood enters right atrium
(2) Flows into right ventricle, pumped through pulmonary arteries to lungs
(3) Picks up 02, discards CO2, flows through pulmonary veins into left atrium
(4) Flows into left ventricle, pumped through aorta into rest of body’s blood vessels
Blood Pressure and how heart beat contract/relax
Force exerted by the blood on the walls of the blood vessels, created by the pumping heart
Systole when the heart contracts (beats)
Diastole when the heart relaxes between beats
Major forms of CVD (x5) ASHPC
ASHPC
Atherosclerosis
Stroke (cerebrovascular disease)
Heart disease and attacks (CHD)
Peripheral Arterial Disease (PAD)
Congestive Heart Failure
Atherosclerosis
Thickening & hardening of arteries, narrowed by deposits of fat, cholesterol, other substances
Endothelial cell damage by smoking, high BP, high insulin or glucose, LDL particle deposit
Fatty plaques accumulate/grow on artery walls, loss of elasticity, restricted blood flow
Vulnerable to blockage by blood clots
Coronary artery, cerebral arteries, limb arteries
Heart Disease & Heart Attack (CHD)
CHD (=CAD) most common form, caused by atherosclerosis
Partial blockage of coronary artery Angina (chest, neck pain)
Complete blockage of coronary artery MI (heart attack) myocardial infarction
Damage or death of heart muscle (myocardium)
The end result of a long-term disease process
Canada: 70,000/year = 1 every 7 min!
Sudden cardiac death (cardiac arrest) resulting from arrhythmia often cause of death in fatal MI
Heart Attack Symptoms
Chest pain or pressure 66%
Arm, neck, shoulder, back or jaw pain
Difficulty breathing, shortness of breath
Excessive sweating; cool, clammy skin
Nausea & vomiting
Loss of consciousness
Fear, anxiety, denial
death first two hours within the first sign of symptoms
) Stroke (cerebrovascular disease)
“Brain attack”
2 million brain cells die per minute; brain ages 3.5 years each hour
Ischemic stroke (87%): Either blood clot forms in a cerebral artery, or blood clot carried in the blood stream that becomes wedged in cerebral artery
Hemorrhagic stroke: Blood vessel in brain bursts, spilling blood into surrounding tissue
Death rates in Canada have declined dramatically
Survivors usually have long lasting disability
Stroke Symptoms
Sudden numbness/weakness of face, arm, leg usually 1 side of body
Sudden confusion, trouble speaking, understanding
Sudden trouble seeing in 1 or both eyes
Sudden trouble walking, dizziness, loss of balance or coordination
Sudden severe headache, no known cause
(4) Peripheral Arterial Disease (PAD)
Atherosclerosis in leg or arm arteries
Significantly increased risk with smoking, diabetes
Risk of amputation
Claudication: aching or fatigue in leg with exertion
Rest Pain: more severe stage, artery significantly narrowed or completely blocked
About 800,000 Canadians have PAD
(5) Congestive Heart Failure
Caused by hypertension, atherosclerosis, CHD, MI, diabetes
Damage to heart’s pumping mechanism, fluids back up, seep through capillary walls Edema
Pulmonary edema
400,000 Canadians per year develop
Can be controlled & treated
Major modifiable risk factors (x6) SHHPOD
SHHPOD
Smoking
Hypertension
High cholesterol
physical inactivity
Obesity
diabetes
Smoking
15% of CVD deaths
30% of smoking related deaths are due to CVD
1 pack/d = 2x risk of MI; 2+ packs/d = 3x risk of MI
Smokers 2-3x more likely to die from MI vs. non-smokers
2x risk of stroke
Hypertension
The “silent killer”
20% of Canadian adults (only 2/3 controlled)
Short-term HBP = normal; chronic HBP = health risk.
Cause: increased output of blood from heart, increased resistance to blood flow from arteries
HBP scars & hardens arteries even higher BP
Heart works harder vs. normal, force blood through arteries
Primary vs. secondary hypertension
Age, OCP, obesity, First Nations/African/Asian, inactivity, stress, alcohol, high-fat/high-salt diet
Lifestyle modification, Sodium restriction, Medication
High cholesterol
Important component of cell membranes, sex hormones, Vit D, fluid coating lungs, protective sheaths around nerves
Cholesterol not used by cells spills out & collects on artery walls
Does dietary cholesterol have big impact on blood cholesterol?
Chol carried in blood on lipoproteins
LDL: carries chol from liver to tissues; Too much = BAD
HDL: carries unused chol back to liver for recycling = GOOD
40% of Canadians have high blood cholesterol
Optimal Levels: LDL < 3.3 mmol/L; HDL men > 1.0 mmol/L, women > 1.3 mmol/L; Tg < 1.7 mmol/L; TC:HDL ratio <5.
Lowering TC reduced risk of heart attack; raising HDL may even reverse plaque formation on artery walls
Lifestyle modification : Increasing fibre, reducing Sat + Trans fats, PA, weight loss, quit smoking
physical inactivity
PA = the magic pill?
Reduces BP & HR, increases HDL, helps maintain healthy weight, improves condition of blood vessels, prevents/controls diabetes
Risk of heart attack cut by 50% with just 3 hrs of brisk walking per week
Obesity
Risk of CVD death 2-3x higher
Weight maintenance also important
Excess body fat hypertension, high chol, insulin resistance, diabetes, endothelial cell dysfunction
PA & Fitness strong positive influence on CVD health in individuals who are overweight/obese
Recall: “Fit-Fat” paradox
Modest weight reduction 5-10% of body weight reduced CVD risk