Chronic Diseases (CVD and Cancer) Flashcards
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
diabetes
Elevated blood glucose, due to insufficient insulin or inadequate action of insulin
2x risk of CVD for men, 3x risk for women: Most common cause of death for diabetics
Diabetes obesity, hypertension, high cholesterol
Type 2 diabetes = “adult-onset” diabetes?
Pre-diabetes: Healthy diet + PA vs. medication
Modifiable contributing risk factors
High Triglycerides e.g. “hypertriglyceridemic waist”
Psychological & Social factors: Stress, chronic hostility/anger, emotional suppression, depression, chronic anxiety, social isolation, low SES
Alcohol & other drugs
Inflammation/C-Reactive Protein: High levels= substantially increased risk of MI & stroke
Non-Modifiable risk factors
Heredity: for both CVD itself + risk factors
Age: 65+
Being Male: especially at younger age, greater risk of MI, hypertension, stroke. ** Estrogen=protective
Ethnicity: Aboriginal, South Asian, African: Higher rates of hypertension, heart dx, stroke
Prevention
Diet: Decreased Sat + Trans fat, increased fibre + whole grains, reduced sodium/increased potassium, moderate alcohol, other diet factors
Exercise! Meeting the Canadian PA Guidelines
Avoid Tobacco
Know (& manage if necessary) your BP
Know (& manage if necessary) your Chol levels
Effective coping & stress management
Cancer
> 225,000 new cancer diagnoses & >80,000 deaths / Year
665 Canadians per day (28/hr) diagnosed with cancer
238 Canadians per day (10/hr) die from cancer
* > 50% of new cases: Lung, Breast, Colorectal, Prostate
* 2 in 5 Canadians will develop cancer in lifetime; 1 in 4 will die from cancer.
* 60% of Canadians diagnosed with cancer survive ≥ 5 years after diagnosis.
who gets cancer
Approx. 90% of new cancers are diagnosed over age 50
Approx. 44% diagnosed over age 70
<1% at age 0-19
who dies from cancer
more males died from cancer than females
Probalility of surviving cancer
five year relative survial
10 most common cancers in men in order from most to least
Prostate
all other cancers
lung
colorectal
bladder
non-hodgkin lymphoma
kidney
leukemia
melanoma
pancreas
oral
10 most common causes of cancer death in men in order from most to least
Lung
all other cancers
colorectal
prostate
pancreas
bladder, esophahus, leukemia
non-hodgkin lymphoma
stomach
brain
10 most common cancers in women in order from most to least
Breast
all other cancers
lung
colorectal
body of uterus
thyroid
non-hodgkin lymphoma
melanoma
ovary
leukemia
pancreas
10 most common causes of cancer death in women in order from most to least
all other cancers
lung
Breast
colorectal
pancreas
ovary
non-hodgkin lymphoma
body of uterus
leukemia
brain, stomach
What is Cancer?
Abnormal, uncontrolled multiplication of cells that, if untreated, can ultimately cause death
Tumour (neoplasm) – a mass of tissue that serves no physiological purpose
Benign vs. Malignant
benign tumors generally don’t invade and spread, malignant cells are more likely to metastasize, or travel to other areas of the body
Metastasis via lymphatic system or bloodstream
Some cancers (e.g. Leukemia) do not produce a tumour
Stages of Cancer
stage 0 – carcinoma in situ a precancerous change
stage 1 – the tumour is usually small and hasn’t grown outside of the organ it started in
stages 2 and 3 – the tumour is larger or has grown outside of the organ it started in to nearby tissue
stage 4 – the cancer has spread through the blood or lymphatic system to a distant site in the body (metastatic spread)
Most common cancers
- Lung
- Breast and prostate
- colorectal
Lung cancer
Most common cause of cancer death in Canada
85% could be prevented by avoiding exposure to tobacco smoke
Difficult to detect early; difficult to cure
50% 5-yr survival if detected early; 15% 5-yr survival overall
breast and prostate
Most common cancer in women: 1 in 8 women
1 in 34 women will die from it
Age (80% > age 50), strong genetic component, early menstruation, late menopause, no children, HRT, obesity, physical inactivity, diet, alcohol
Early detection: Screening every 2yrs > age 50
Most common cancer in men: 1 in 8 men
1 in 30 men will die from it
Age (80% > age 65), physical inactivity, obesity, diet
Early detection: Screening > age 50
colorectal
1 in 16 men, 1 in 18 women
1 in 38 men, 1 in 43 women will die from it
Age (50% > age 70) & heredity
Alcohol, smoking, physical inactivity, obesity, diet
Screening is effective: Recommended > age 50, could reduce incidence by 80%… but only 50% of adults do it
Major known cancer causes
DNA, genetics, heredity
Gene mutations can be inherited, but most are caused by environmental factors (carcinogens)
Tobacco
85% of lung cancers, 30% of all cancer deaths
Physical Inactivity & Obesity
Especially breast & colon cancers
Diet (other card)
Environmental Carcinogens (other card)
Major cancer causes (diet)
Diet
High consumption of dietary fat, processed & red meats
Alcohol
Fried foods
Acrylamide = human carcinogen (also: tobacco smoke)
Help reduce risk
Fibre
Fruits & Vegetables
“anti-carcinogens”: Vit A, C, E, B9 (folate); selenium, Ca
Phytochemicals in plants
Environmental Carcinogens
Microbes (viruses, bacteria, parasites): 15% global cancers
HPV, Helicobacter pylori, Epstein-Barr, Herpes, Hep B & C
Ingested chemicals
Preservatives & additives: Some are anti-oxidants (good);
Others not good e.g. nitrates/nitrites in processed meats prevent bacteria growth/food poisoning, but can combine with dietary substances in stomach to form nitrosamines
Environmental/Industrial pollution
Air/water: < 2% of cancer deaths
Occupational: 5% of cancer deaths (N. America, vs. Eastern Europe, Former USSR)
Radiation
Medical x-rays, radioisotopes, UV rays
Major warning signs of cancer (x7) (caution)
Change in bowel or bladder habits
A sore that does not heal
Unusual bleeding or discharge
Thickening or lump
Indigestion or difficulty swallowing
Obvious change in wart or mole
Nagging cough or hoarseness
Cancer Treatment
Surgery: Primary & often most useful Tx
Radiation: Tumour cells killed by gamma rays or x-ray beams; radioactive ‘seeds’ for small tumours – Destroys normal cells also, but can be precisely directed
Chemotherapy: Use of cell-killing drugs to destroy rapidly dividing cancer cells – Normal slow-growing cells are not destroyed, but tissue damage = side effects
Targeted treatments: Immunotherapy, hormone therapy, etc.
