Public Health Flashcards
(462 cards)
What is the #1 cause of death in the U.S.?
Cardiovascular disease
What is the #2 cause of death in the U.S.?
Cancer
What is the #3 cause of death in the U.S.?
Unintentional injuries
What is the #4 cause of death in the U.S.?
Chronic lower respiratory diseases
What is the #5 cause of death in the U.S.?
Stroke
What is the #6 cause of death in the U.S.?
Alzheimer’s Disease
What is the #7 cause of death in the U.S.?
Diabetes
What is the #8 cause of death in the U.S.?
Pneumonia and influenza
What is the #9 cause of death in the U.S.?
Nephritis, nephrosis, and nephrotic syndrome
What is the #10 cause of death in the U.S.?
Suicide
What is the CEA Winslow definition of public health?
The science and art of preventing disease, prolonging life, and promoting physical health and efficiency…
(PrevProlProm)
Name a few of the greatest public health achievements of the 20th and 21st centuries.
Immunizations Motor-vehicle safety Workplace safety Family planning Fluoridation of drinking water Infectious disease control
Describe Leavell and Clark’s Levels of Prevention (Primordial, primary, secondary, tertiary, and quaternary).
Primordial - Population measures (E.g. legislation)
Primary - Addressing individual risk factors (E.g. proper nutrition)
Secondary - Screenings (E.g. pap smears)
Tertiary - Disease treatment (E.g. a type 1 diabetic receiving insulin administration)
Quaternary - Reducing over-medicalization (E.g. strict opioid administration to prevent unnecessary use)
Define incidence rate.
The number of new cases of a disease over a certain period of time
Define prevalence rate.
The number of existing cases within a certain window of time
Define social determinants of health.
The social determinants of health are the conditions in which people are born, grow, live, work and age. These circumstances are shaped by the distribution of money, power, and resources at global, national and local levels. The social determinants of health are mostly responsible for health inequities - the unfair and avoidable differences in health status seen within and between countries (WHO definition).
What is the difference between absolute and relative poverty?
Absolute poverty is defined as living on less than $2 a day and refers to all individuals under this amount globally.
Relative poverty refers to the difference in wealth between an individual and those in their community (E.g. an individual that makes $40,000 per year living near an individual making $200,000 per year is relatively impoverished in comparison).
What is the federal poverty level?
The recognized U.S. poverty line.
Examples:
< $12,000 per year for individuals
< $16,500 per year for a family of two
(The amount steadily increases with the size of the family)
What is the absolute poverty level?
Living on less than $2 per day (1 billion individuals are in this bracket worldwide)
What is the difference between active and passive immunity?
While both are forms of acquired immunity, active immunity refers to immunity in which the individual synthesizes their own antibodies. Passive immunity refers to immunity in which the individual receives pre-synthesized antibodies from an external source.
Give an example of active natural immunity.
An individual gets exposed to a pathogenic antigen and begins synthesizing their own antibodies.
Give an example of active artificial immunity.
Vaccination
Give an example of passive natural immunity.
A mother passing her antibodies (IgA) to her baby through her breast milk
Give an example of passive artificial immunity.
Lab-synthesized gammaglobulins being administered (E.g. following a hepatitis needle stick or bite by a rabid dog)
Define ecology.
The study of factors influencing the abundance and distribution of organisms
Define competition and cooperation.
Competition - Driving force of natural selection (Remember viruses damaging each other and competing for resources) Cooperation - Differing species working together to benefit all species involved (Remember biofilms)
What is a biofilm?
What is quorum sensing?
A biofilm is a collection of bacteria cooperating and working together. Biofilms often form on hospital catheters / instruments and are responsible for many nosocomial infections
Quorum sensing is the cell-to-cell communication that regulates the density of bacteria growth so they can share resources.
What is a habitat?
The physical area a species inhabits
What is an ecological niche?
The habitat + behaviors of a particular species
How many species can occupy the same ecological niche?
Only 1. Either one species will evolve to separate the niches, or one will out-compete the other, resulting in its extinction.
How does climate change affect ecology (Particularly disease dynamics)?
1) Warming can cause a shift in timing, where epidemic peak may occur at a different time of year than it did in the past 2) Warming can cause more epidemic “cycles”, meaning that there may be two epidemic peaks in the same year 3) Warming can cause overall epidemic intensity to either increase or decrease, depending on whether the pathogen can well-tolerate the new climate.
What is it mean for a disease to be zoonotic?
A zoonotic disease is a disease that has its origins in a species other than humans (This includes vector-borne diseases as well as direct zoonotic diseases)
What does it mean for a disease to be frequency-dependent?
Transmission rates increase with the number of infectious people, but it doesn’t matter how geographically dense they are. (I.e. STDs and some vector-borne diseases)
What does it mean for a disease to be density-dependent?
Transmission rates increase with population density of the host. (E.g. influenza)
What is it called when an area has everything necessary for disease to spread (Pathogen, climate, resources, etc.), but humans don't inhabit the area?
A silent zone
What happens when a large population enters a silent zone?
There will be an epidemic
What are the principal modes of transmission? (8) | PAAWSFFF
Perinatal Airborne Animal bites Water-borne Sexual Fecal-oral Fomite Food-borne
```What is the name of this type of zoonotic transmission cycle?
Human --> Human --> Human
Direct human-to-human
(E.g. influenza)
What is the zoonotic transmission cycle in which a disease principally found in animals is passed to a human (Who does not pass it to other humans)?
Direct zoonosis
(E.g. rabies)
What is the zoonotic transmission cycle if the disease can only be passed from human to human via an insect or animal?
Vector-borne
(E.g. malaria)
If a disease can only be passed to humans from animals via a vector, what is the zoonotic transmission cycle?
Vectored zoonosis
(E.g. encephalitis)
(Here's the trickiest one)
If a disease can only be passed to humans from animals via a vector, and then it is transmitted from human to human via a vector, what is the zoonotic transmission cycle?
Anthropo-zoonosis
(E.g. yellow fever)
What is a reservoir?
A host species for a viral disease that does not usually become seriously ill from the disease
What are some examples of common reservoirs?
Bats, mice, and birds
What is the term that describes the transference of a disease from one species to another?
A spillover event
How does biodiversity protect us from disease?
The greater the number of species in a given area, the fewer interactions humans are likely to have with a particular disease-carrying species (Remember the Lyme disease example). This is called the dilution effect.
What is disease emergence?
The process by which a disease gains strength in the general population following a spillover event
Are deer ticks born with Lyme disease?
Where do they typically get it?
No.
Usually, they get Lyme disease from their first blood meal (If the meal is infected, as white-footed mice often are).
Describe the life cycle of a tick.
Uninfected larva hatch in late Summer -->
The feed on a (possibly) infected small animal -->
They molt and become nymphs till the end of Winter -->
In Spring/Summer/Fall they feed on vertebrates -->
Ticks that feed on deer mate and lay eggs
Superbug
When there are high morbidity and mortality due to a bacteria that has become resistant, it is often referred to as a superbug.
Extra info: Resistance to pharmacotherapy is not only an issue for bacteria, but it can arise in cancer cells, parasites, fungi, and other infections. Bacteria with acquired resistance include TB, S. aureus, Acinetobacter, E. coli, and V. cholera.
Why mechanisms for resistance exist in nature
Microscopic organisms have been battling one another for millions of years by producing chemicals that can limit the growth of other organisms. Resistance to these chemicals has evolved in synchronization with them.
Mechanisms for resistance are therefore not new to human populations. They have been in development long before we ever started using antibiotics therapeutically. In fact, a large portion of your microbiome is already resistant to antibiotics you have never been exposed to.
(Example: Penicillinase was discovered in the natural bacterial population in samples that pre-date the use of therapeutic penicillin.)
Horizontal gene transfer
When a bacteria takes up DNA from another source, it is called horizontal (or lateral) gene transfer (HGT)
Genetic island/cassette
The part of a bacteria’s genome resulting from HGT is called a genomic island, or a genetic cassette. Genomic islands can confer resistance in the new bacteria.
Vertical gene transfer
If a gene is inherited directly from a “parent” bacteria during reproduction, it is called vertical gene transfer (VGT).
Intrinsic resistance
In the case of intrinsic resistance, no mutation is necessary to confer resistance. The bacteria simply overcomes the antibiotic by making more copies of the protein that the antibiotic targets.
Ways in which resistance can develop (change drug target, modify cell walls, metabolize antibiotic, etc.)
It is important to note that resistance genes exist in bacteria with or without selection (does not “cost” them anything).
There are many different biological mechanisms by which they work. These include:
1. changing the shape of the antibiotics target protein,
2. developing the ability to metabolize the antibiotic,
3. developing the ability to recognize and actively pump out the antibiotic
Conjugation
Transfer of genetic material from bacteria to bacteria through a sex pilus connection
Transduction
Transfer of genetic material from bacteria to bacteria via a bacteriophage (Virus that infects bacteria)
Transformation
Direct uptake of 'spilled' DNA from outside the bacterial cell into the bacteria
The roles of humans in creating resistance
1. Less than ½ of the therapeutic antibiotics in existence are for human use.
2. There is a dramatic overprescription of antibiotics in the U.S. and internationally (Often for viral infections).
3. In agriculture, antibiotics are often used prophylactically because it was thought that they improve weight gain of animals (not to treat or prevent infection).
What can be done to mitigate the problem of antibiotic resistance?
Identifying resistant bacteria earlier, and developing new methods for identifying antibiotics or other antimicrobial therapies.
For example, genotyping of strains in clinics to test for resistance is on its way to becoming common practice. Another common strategy is to use combinations of antibiotics, so that the bacteria is not able to acquire resistance. This is a method used often in the treatment of drug-resistant TB.
What is a vector-borne disease?
Diseases that are transmitted between hosts by another species
(The vector is typically not infected, but that is not true in cases such as malaria)
What specific ecological challenges do vector-borne diseases produce?
How do we eliminate/control the vector without wide-ranging ecological effects?
How will climate change affect vector and host distributions?
What are some methods to prevent vector-borne disease?
Indoor residual spraying
Bednets / window screens
Genetic modifications
Larvae extermination
Name four vector-borne diseases.
Malaria
Dengue fever
Zika
Chikungunya virus
Etc.
How is the chikungunya virus transmitted?
Where is it found?
What is its incubation period?
What are some associated signs/symptoms?
How is it treated?
Mosquito-borne
Central / Southeast Asia and Sub-Saharan Africa
1 - 12 days
Rash, fever, polyarthralgia, vomiting, headache
Anti-inflammatories
How is the Dengue fever virus transmitted?
Where is it found?
What are some associated signs/symptoms?
How is it treated?
The Aedes aegypti mosquito
More than 100 countries in both hemispheres
Crushing bone pain (It is often called 'bone break fever'), fever, lethargy, can be hemorrhagic
How is the Zika virus transmitted?
Where is it found?
What are some associated signs/symptoms?
The Aedes Agypti mosquito
Microindonesia, Brazil, several other locations
Usually, mild symptoms lasting a few days to a week
Causes microcephaly and Guillan-Barre Syndrome among infants of affected mothers
How long can Zika remain present in semen? How long should a woman wait after her symptoms abate to try to have children?
6 months
2 months
Where did HIV come from?
It is a zoonotic disease that originated in non-human primates as SIV.
When was HIV first reported in the U.S.?
1981
What populations are especially at risk for HIV transmission?
Intravenous drug users
Homosexual men (44x higher risk than heterosexual men)
Impoverished women (Especially those that have little sexual control in their relationships)
Prostitutes
Healthcare workers (Due to needle sticks and accidental fluid exchange)
African-Americans, Asian-Americans, and Pacific Islanders also experience higher rates of HIV in the US than is found in other ethnic groups (Likely from a socioeconomic or stigma-related disparity).
What does it mean that HIV is a retrovirus?
It means that, upon infection, the virus (RNA) is transcribed (By reverse transcriptase) to DNA and inserted into the host genome after infection. This makes it very hard to treat as it becomes part of our own DNA!
What does it mean that HIV is a lentivirus?
It replicates slowly. There can be long incubation and latency periods between infection and symptoms
How does HIV spread?
What is seroconversion?
HIV spreads via bodily fluids such as blood, blood products, semen, rectal or vaginal fluids, or breast milk.
Seroconversion is when the immune system first begins producing antibodies against HIV. This usually happens a few weeks after the initial infection.
What type of human cell is preferentially infected by HIV?
What are the initial signs/symptoms of infection?
The virus preferentially infects CD4+ Helper T-cells (A type of white blood cell).
Upon initial infection, there are acute symptoms which are typically flu-like.
When has an HIV infection officially advanced to AIDS?
When CD4+ Helper T-cell count below 200/ml (normal counts are 500-1500 per ml).
What are some of the rare infections that typify AIDS (Due to decreased host immune response)?
- Pneumocystic (fungal) pneumonias
- Pneumonia due to cytomegalovirus, toxoplasmosis, herpes simplex, or gastrointestinal protozoa
- Some patients develop a rare form of cancer called Kaposi’s sarcoma. The cancer is caused by Kaposi sarcoma herpesvirus (KSHV) that inserts its genes into the host (Kaposi’s sarcoma is 20,000 times more common in AIDS patients than in the general public).
What is ART/ARV? Do they fully cure HIV?
Antiretroviral Therapy
They do not fully cure the disease; they only keep the viral load down.
What is an HIV superinfection?
When an HIV-infected patient on ARV becomes infected with an additional strain of HIV (Double HIV infection).
What is vertical HIV transmission?
Transmission from an infected mother to her child.
Transmission can occur in utero, during delivery, or through breastfeeding. Breastfeeding is the most common type of transmission from mother to child.
How is HIV different in children than adults?
More recurring opportunistic bacterial and viral infections, (but they are less likely to develop Kaposi’s sarcoma) more rapid disease progression as well
How can vertical HIV transmission be prevented?
A special ARV regimen (Highly effective).
The Pediatric AIDS Clinical Trials Group (PACTG) 076 AZT regimen is a series of ARV drugs given in different amounts during pregnancy, delivery and just after birth to prevent transmission of HIV to a child.
What are a few general methods by which to prevent HIV spread?
Condom distribution
Education
Prophylactic ARV treatment (reduces transmission by 60-80%)
Needle exchange programs
Male circumcision
Do all HIV-infected individuals in the U.S. know they are infected?
No. About 20% of HIV+ persons in the United States are unaware of their infection.
What is the bacterium responsible for TB infections?
Mycobacterium tuberculosis
What percentage of the world population is infected with latent TB today?
What percentage of those infected with latent TB will become sick with active TB at some point in their lifetimes?
33%
10%
How is TB spread?
What body system does it most commonly infect? Can it infect other systems?
Respiratory droplets (Airborne transmission)
Respiratory system
Yes, TB can disseminate to organs other than the lungs
What is Milliary TB?
Many small areas of local TB spread throughout an organ
What human cell in the respiratory tract is preferentially infected by TB bacterium?
Alveolar macrophages
After alveolar macrophages are infected by TB bacterium, what happens?
Immune cells surround the area, promote inflammation, and accumulate as dead cells
(This forms nodules called granulomas)
Does the immune system usually manage to wipe out all the TB bacterium on its own?
No, the immune system usually only manages to keep the bacterium at bay
(This is called latent TB and is true for 90% of infected individuals)
What is it called when a latent TB becomes active?
Reactivation
How is TB diagnosed?
The Mantoux Tuberculin test (TB antigen injected under the skin) and chest x-rays
What is a Gohn focus?
A TB granuloma large enough to be seen on x-ray
What is it called if a patient presents with a Gohn focus and regional lymph node involvement?
This is a Gohn complex
What is the difference between primary vs. secondary TB infection?
Primary infection is the initial host encounter with TB bacterium.
A secondary infection refers to EITHER being infected with TB after being cured OR reactivation of latent TB
What are the signs/symptoms of TB infection?
Fever, cough, bloody sputum, weakness, and chest pain.
What is the most common cause of death among AIDS patients?
TB
How is TB treated?
- 2 initial months of chemotherapy (antibiotics) and varying amounts of continuing treatment (No need to memorize drug names, but know it’s a drug cocktail given for months).
- Patients may be asked to take a complex regimen of drugs including:
Isoniazid (an anti-metabolite)
Rifampin (inhibits RNA polymerase)
Ethambutol (inhibits cell wall formation)
Pyrazinamide (converts to an acid and accumulates, killing the cell).
What are our main prevention strategies for TB?
Vaccination (18-30% efficacy)
Prophylactic antibiotics
Isolation of infected individuals
DOTS program (Involves much closer patient-physician interaction and follow-up than usual)
What is MDR-TB?
Where is it present?
Multi-drug resistant TB
In all countries
What is XDR-TB?
What is TDR-TB?
Extremely-resistant TB
Totally resistant TB
What is malaria?
A protozoan parasite that exists in many different animals
What is the basic evolution of malaria?
Plasmodium malariae -->
Plasmodium vivax -->
Plasmodium falciparum
How has Plasmodium vivax impacted human evolution?
Plasmodium vivax enters human erythrocytes via the Duffy receptor (An RBC glycoprotein). Being 'Duffy-less' is now a dominant human mutation in most Africans, and so P. vivax is more prevalent in Europe and Asia
How has Plasmodium falciparum affected human evolution?
Hemoglobin disorders confer some immunity to P. falciparum, and so now 1/14 of humans carry genetic mutations related to thalassemia, sickle-cell anemia, ovalocytosis, and other hemoglobin disorders.
What are the 3 stages of the malaria lifecycle?
Inside the mosquito --> Inside the human liver --> Inside the human bloodstream -->
What are the signs/symptoms of malaria?
Fever, chills, nausea, and sweating
What is the average incubation period for malaria?
~10 days
The malaria types, P. vivax and P. ovale can remain dormant for long periods of time. What does this trait make them?
Hypnozoites
What are some of the main prevention methods for malaria?
Insecticide-treated bed nets
Indoor residual spraying
Prophylactic medication (E.g. Doxycycline and primaquine)
Possible vaccines in the pipeline
What are the main anti-malarial drugs?
Quinine and artemisinin
(Resistant strains of malaria are developing to both these drugs)
What is the adult obesity prevalence rate in the U.S. (As of 2014)?
36.5%
What percentage of the U.S. is overweight or obese (As of 2014)?
68.5%
What percentage of U.S. children are obese?
17%
What is the BMI equation?
Kilograms / meters2
(Or) lbs. / inches2 x 703
What is an underweight BMI?
What range is a normal BMI?
What range is an overweight BMI?
≤ 18.4
18.5 - 24.9
25 - 29.9
What range is an obese class I BMI?
What range is an obese class II BMI?
What is an obese class III BMI?
30 - 34.9
35 - 39.9
≥ 40
Do the adult BMI categories work for children?
Not quite. We use a percentile chart to standardize the BMIs for all the variation in child growth rates.
What is an underweight percentile for a child?
What is an overweight percentile?
What is an obese percentile?
< 5th percentile
> 85th percentile
> 95th percentile
Which states have the highest burden of obesity?
How does obesity break down by age?
By gender?
By race?
Higher rates among the middle-aged and older.
Slightly more women than men
Blacks > Hispanics > Whites > Asians
What are some of the complications and common comorbidities of obesity?
CVD
Obstructive Sleep Apnea
GERD
GI issues
Cancer
Stroke
Diabetes
Heart failure
Hypertension
Dyslipidemia
Osteoarthritis
Atherosclerosis
Atrial fibrillation
Alzheimer’s Disease
Non-alcoholic fatty liver disease (NAFLD)
Polycystic Ovarian Syndrome (PCOS)
Surgical and anesthetic complications
Psychosocial disorders
etc...
How does obesity relate to CVD?
1. Increased body mass leads to increased systemic blood pressure. →
Increased BP leads to chronic cardiac overload →
Overload leads to cardiac hypertrophy and strain.
2. Lower HDL and higher LDL levels lead to atherosclerotic blood vessels and increased systemic blood pressure.
How does obesity relate to diabetes?
1. Excess weight and body mass disrupt normal metabolic processes’ ability to regulate blood sugar levels →
Hyperglycemia and diabetes often result.
2. Obesity is generally related to excessive and long-term carbohydrate intake, very directly leading to chronic hyperglycemic conditions.
How does obesity relate to cancer (Obviously it depends on the type of cancer)?
1. Increased levels of insulin and insulin growth factor (IGF-1) lead to excess growth.
2. Excess adipose tissue increases estrogen levels (Affecting breast and endometrial cancer rates).
3. Fat cells are suspected to also affect cancer cell growth regulation in a yet unknown way.
What is the difference between visceral and subcutaneous fat? Which is more harmful in excess?
Visceral fat is the fat that sits between and compresses the organs of themselves (Usually gives rise to an apple-shaped torso).
Subcutaneous fat is the less harmful fat that sits just below the skin (Usually gives rise to a pear-shaped torso).
What are the five factors involved in metabolic syndrome?
How many of the factors must be present to classify an individual as having metabolic syndrome?
Blood pressure, triglycerides, HDL cholesterol, plasma glucose, and abdominal obesity.
3/5
How can obesity be diagnosed?
BMI (Principal method)
DEXA scanning
underwater weighing
What are the lab values involved with the following five factors of metabolic syndrome?
Blood pressure
Plasma triglycerides
Fasting plasma glucose
Abdominal obesity
HDL cholesterol
Blood pressure (High) ≥ 130 / 85 mmHg
Plasma triglycerides (High) ≥ 150 mg/dl
Fasting plasma glucose (High) ≥ 100 mg/dl
Abdominal obesity (High) ≥ 35" (women); ≥ 40" (men)
HDL cholesterol (Low) ≤ 40 mg/dl
What is the only method of obesity treatment and management that has shown to be consistently effective in morbidly obese populations?
Gastric bypass surgery
Which cholesterol is associated with positive health benefits?
Which cholesterol is associated with negative health benefits?
HDL
LDL and VLDL
What are the main types of bariatric surgery used in obesity management?
Gastric sleeve bypass
Gastric roux-en-y bypass
Gastric banding
What is diabetes mellitus?
A condition in which blood sugar is highly elevated.
What are the two main types of diabetes mellitus?
Which is more common in the U.S.?
Type 1 and type 2
Type 2 (90-95% of cases)
Is the pancreas an endocrine or exocrine organ?
Both
What are the primary endocrine secretions of the pancreas?
What are the clusters of endocrine cells called?
Insulin and glucagon secretion
Islets of Langerhans
Which pancreatic cells secrete insulin?
Which pancreatic cells secrete glucagon?
Beta cells
Alpha cells
What are the primary functions of insulin?
Decrease blood glucose by:
Increasing glucose transport into adipose and skeletal muscle tissues through GLUT-4 transporters
Increasing glycogenesis
Decreasing gluconeogenesis
Decreasing lipolysis
What are the primary functions of glucagon?
Increase blood glucose by:
Increasing glycogenolysis (Glycogen breakdown)
Increasing gluconeogenesis (Protein breakdown)
Increasing lipolysis (Fat breakdown)
What is the primary dysfunction in T1DM?
Insulin deficiency due to autoimmune destruction of pancreatic beta cells
What is the primary dysfunction in T2DM?
Insulin insensitivity
What is a hemoglobin A1c measurement?
What is it used for?
A measure of how much glucose has gotten 'stuck' on hemoglobin for the past 120 days (The lifespan of an RBC).
Used as a measure of long-term blood glucose control.
What are the normal, pre-diabetic, and diabetic A1c readings?
Normal < 5.7%
Pre-Diabetic 5.7 - 6.4%
Diabetic > 6.4%
Define hyperglycemia.
Elevated blood sugar
What is a fasting plasma glucose (FPG) reading?
A measurement of an individual's blood glucose levels during a fasting state
What are the normal, pre-diabetic, and diabetic FPG readings?
Normal < 100 mg/dl
Pre-Diabetic 100 - 125 mg/dl
Diabetic > 125 mg/dl
At what age does T1DM usually manifest?
At what age does T2DM usually manifest?
Early. Often between 12 and 18 Later in life
Usually after 35 or 40
What are the cardinal signs and symptoms of diabetes? (Remember the 3 P's)
Polyphagia (Excessive hunger)
Polydipsia (Excessive thirst)
Polyuria (Excessive urine production)
Besides the 3 P's, what are some other signs and symptoms of diabetes?
There are many systemic effects, including, but not limited to:
Peripheral neuropathy
Diabetic retinopathy
Infection and gangrene
Acanthosis nigricans
Weight loss (Mainly in T1DM)
Renal damage
What is the extreme and life-threatening effect of T1DM?
Diabetic ketoacidosis (DKA)
What is the extreme and life-threatening effect of T2DM?
Hyperosmolar Hyperglycemic Non-Ketotic Coma (HHNC)
How is T1DM typically treated?
Insulin administration and diet adjustment
How is T2DM typically treated?
Diet and weight loss; oral hypoglycemic medications as needed (E.g. metformin)
What is the leading cause of death among individuals with T1DM?
Renal failure
What is the leading cause of death among individuals with T2DM?
Heart failure
Where does diabetes mellitus fall in as a leading cause of death in the U.S.?
#7
What geographic region in the U.S. has the highest prevalence of diabetes mellitus and in what racial group?
The Southeastern United States
(The obesity/stroke/diabetes belt)
African-Americans are at increased risk over other racial groups
Which type of diabetes mellitus holds a stronger genetic disposition, type 1 or 2?
Type 2
What factors can greatly increase one's chances of developing T2DM?
Obesity, metabolic syndrome, high-sugar and high-fat diet, family history
What effect have gastric bypass surgeries been shown to have on obese patients with T2DM?
A complete cure of some patients' T2DM (As well as an average of 2/3 excess weight lost)
What is diabetic ketoacidosis (DKA)?
Usually seen only in T1DM, glucose is unable to make it into the cells, the cells begin to starve, and lipids are broken down at a quick rate for energy production. Lipid breakdown leads to the production of ketone bodies that are acidic to normal blood pH. Blood pH drops and the individual enters a coma.
What are the ketone bodies produced during DKA?
Beta-hydroxybutyrate and acetoacetate
Define hypoglycemia.
What is a danger of extended periods of hypoglycemia?
Low blood sugar (< 70 mg/dl)
Brain damage
What are the ABCs of diabetes control (After an individual has already been diagnosed)?
A1c < 7%
Blood pressure < 130 / 85
Cholesterol
LDL < 100 mg/dl
HDL > 50 mg/dl (Women) > 40 mg/dl (Men)
At what BMI should most Americans start being screened for diabetes?
Who else should be screened?
BMI ≥ 25 (Overweight)
≥ 45 years of age
Family history of T2DM
History of gestational DM
What is the BMI at which members of the Asian population should be screened for diabetes?
23
(Screen at 23)
What is the technical term for glucose production through the breakdown of fat and protein?
Gluconeogenesis (glucose-new-production)
(Promoted by glucagon; inhibited by insulin)
What is the technical term for fat breakdown?
Lipolysis
(Promoted by glucagon; inhibited by insulin)
What is the technical term for glucose breakdown to pyruvate?
Glycolysis
(Inhibited by glucagon; promoted by insulin)
What is the storage form of glucose?
Where is it found?
Glycogen
Liver and skeletal muscle tissue
What is the technical term for glycogen synthesis?
Glycogenesis
(Inhibited by glucagon; promoted by insulin)
What is the technical term for glycogen breakdown (producing glucose)?
Glycogenolysis
(Promoted by glucagon; inhibited by insulin)
What is primary (essential) hypertension?
For what percentage of HTN cases does it account?
An idiopathic form of HTN (cause unknown)
90%
What is secondary HTN (responsible for 10% of cases)?
HTN due to some underlying disease
What is the normal blood pressure classification?
< 120 / 80 mmHg
What is systolic blood pressure? What is diastolic blood pressure?
Systolic BP = BP while the ventricles are contracting - Top number (e.g. 120 / 80)
Diastolic BP = BP while the ventricles are relaxing - Bottom number (e.g. 120 / 80)
What is the proper classification for an individual with a BP ranging from 120 - 129 / 80 mmHg?
Elevated BP
(No longer known as pre-HTN)
What is the stage 1 HTN pressure reading?
130 to 139 / 80 to 89 mmHg
What is the stage 2 HTN pressure reading?
≥ 140 / ≥ 90 mmHg
At what BP reading is an individual considered to be in a hypertensive crisis (at immediate risk for organ damage)?
≥ 180 / ≥ 120 mmHg
What are some common complications of HTN?
Stroke
Atherosclerosis
Thrombosis
Aneurysm formation
Organ damage
(Not a comprehensive list)
What is the DASH diet?
An antihypertensive diet focusing on the reduction of salt and lipid intake
What lifestyle modifications can be utilized to lower BP?
Weight loss
Salt intake reduction
Physical activity increase
Meditation
What is the REGARDS study?
the REasons for Geographic And Racial Differences in Stroke
Define ischemia
Lack of oxygen delivery to tissues
Define infarct.
Cell damage and death due to loss of blood flow
What is the definition of a transient ischemic attack?
A 'mini-stroke' that results in signs and symptoms that have completely resolved 24 hours after the insult
Just as heart attack refers to an acute myocardial infarction, what is the term that can also refer to a cerebral infarction (stroke)?
Cerebrovascular attack (CVA)
What are the two main types of stroke?
Which is more common?
Which is more deadly?
Ischemic (thrombotic; loss of blood supply) and hemorrhagic (rupture leads to blood entering cranial space)
Ischemic is more common (85-90% of cases)
Hemorrhagic is more deadly
What is the core zone of a stroke? What is the ischemic penumbra?
The core zone refers to the infarcted tissues following complete loss of blood supply
The penumbra refers to the affected area of tissue that is often still viable tissue but will die if perfusion is not reestablished; there is usually some collateral circulation supplying the tissues with some blood flow
Define aneurysm.
A weakening or outpouching in the blood vessel wall (a ballooning that is more likely to rupture than surrounding tissue)
What are some of the risk factors for stroke?
Hypertension (Most important factor)
Metabolic syndrome
Atherosclerosis
Atrial fibrillation
Aneurysms
Race (African-Americans more at risk)
Medical history of thrombotic events
What are some of the common signs and symptoms of stroke?
Headache, weakness, paralysis, dizziness, vision changes, balance changes, drooping facial features, slurred speech, disorganized speech or thoughts
(Physical signs often unilateral)
On which side of the body will a right-sided stroke manifest?
What is the term for this manifestation?
The left side (and vice-versa for a left-sided stroke)
Contralateral
How can stroke be diagnosed?
Clinical presentation, MRI, CT scans, angiography
What medication can be given to prevent thrombotic stroke?
What medication can be given to dissolve the clot that is causing thrombotic stroke?
Aspirin and/or heparin
TPA (tissue plasminogen activator)
Where does stroke fall in the U.S. leading causes of death?
#5
Where in the U.S. leading causes of death does heart disease fall?
CVD is #1 (for the U.S. and the world)
Try drawing out the flow of blood through the pulmonary and systemic circuits.
Define thrombus and embolus
Thrombus = stationary blood clot
Embolus = moving blood clot
(or other clumped substance such as bacteria, fat, air, tumors, amniotic fluid, etc.)
Describe the difference between ischemia and an infarct
Ischemia refers to reduced blood flow to tissues
Infarct refers to tissue necrosis secondary to reduced blood flow
Define the following terms:
Atherosclerosis
Angina
Acute Myocardial Infarction
Atherosclerosis - Arterial hardening due to fatty plaque buildup
Angina - Chest pain
Acute Myocardial Infarction - Infarction of heart tissue
Name the main six coronary arteries discussed in class. What part of the heart does each supply?
Right coronary artery
- Acute marginal artery (Anterior right ventricle)
- Posterior descending artery (Posterior right ventricle)
Left main coronary artery
- Left anterior descending (Anterior left ventricle and interventricular septum)
- Lateral and posterior left ventricle
Which artery is the most common site of an AMI?
The left anterior descending artery
What is the Million Hearts Initiative? Was it successful?
This is awesome:
https://millionhearts.hhs.gov/files/MH-meaningful-progress.pdf
What are the four behavioral components of Life's Simple Seven?
Physical activity
Weight reduction
Diet
Don't smoke
What are the three laboratory tests in Life's Simple Seven?
Blood pressure
Plasma cholesterol
Plasma glucose
Name all seven of the Life's Simple Seven factors.
Physical activity
Weight reduction
Diet
Stop smoking
Blood pressure
Plasma cholesterol
Plasma glucose
Name the type of proteins that help transport cholesterol in the bloodstream (remember, fat is hydrophobic and must be carried by hydrophilic proteins).
Lipoproteins
Which type of lipoprotein removes cholesterol from the bloodstream by taking it to the liver? Is this protective or damaging against heart disease?
High-density lipoprotein (HDL)
Protective
(Happy cholesterol)
(Healthy cholesterol)
(Helpful cholesterol)
Which type of lipoprotein is bound to cholesterol and contributes to atherosclerotic plaque buildup by increasing the quantity of cholesterol deposited into atheromas?
Low-density lipoprotein (LDL)
(Lousy cholesterol)
(Lame cholesterol)
(Loser cholesterol)
What is the underlying problem in angina? Are cells necessarily dying at this point?
Chest pain caused by ischemia in the heart tissues.
This is not necessarily an infarction and so cells are not always dying at this point.
Describe stable (classical) angina.
Ischemic chest pain that begins on physical and/or emotional exertion and subsides on rest and/or intake of nitrates
Describe unstable (crescendo) angina.
Ischemic chest pain that begins at rest and/or exertion and does not subside after rest and/or intake of medication.
Often called crescendo angina as it tends to worsen over time.
Describe Printzmetal (variant) angina.
Ischemic chest pain due to atypical contraction and spasm of the coronary arteries.
Occurs most often in young women
Not related to atherosclerosis
Which type of angina pectoris often shows ST-elevation and is most likely to devolve into an AMI?
Unstable (crescendo) angina
Are there any recreational drugs that can worsen angina or increase the likelihood of acute myocardial infarction?
Cocaine (Vasoactive - causes arterial constriction)
(Also nicotine)
What are the signs and symptoms of AMI? Differentiate between the two sexes.
Women: Typically characterized by flu-like symptoms, fatigue, aches, chest tightness or pain, nausea, dyspnea
Men: More classically associated symptoms such as crushing chest tightness, pain that radiates into the neck and left arm, and dyspnea
How does aspirin prevent AMI?
Through decreased production of thromboxane A2 (A clotting activator) from arachidonic acid
What is the difference between a subendocardial and a transmural AMI?
Subendocardial infarction involves only the innermost layer of the heart.
Transmural infarction involves all three layers of the heart (leads to ST-elevation).
How is the pathophysiology of heart disease different in women than in men?
How does this difference manifest on angiography (X-ray of the blood vessels)?
Men are characterized by macrovascular atherosclerotic plaque buildup (Fat buildup in clumps in the bigger arteries)
Women are characterized by inflammatory processes which lead to microvascular dysfunction and widespread, even occlusion of the smaller arteries
On angiography, this difference often manifests as women's arteries being clearer than men's (even though there may be similar amounts of plaque buildup overall)
What are some mechanisms of heart disease diagnosis?
Electrocardiogram (ECG), coronary angiography, stress test, cardiac enzymes present in blood (high-sensitivity C-Reactive protein (hsCRP) specifically in women)
What is a common cardiac enzyme often found in the blood during an AMI?
Troponin I
Name the three layers of an artery or vein.
Tunica intima (Endothelium)
Tunica media (Smooth muscle)
Tunica externa (Connective tissue)
What is the main risk factor for atherosclerosis?
Hypertension
Describe the general steps of atherosclerosis.
1. The endothelium is damaged
2. Cholesterol is deposited in the ruptured space
3. Macrophages enter the site, die, and become fat-laden foamy macrophages
4. The vessel lumen continues to narrow, pressure increases, and the risk of full occlusion or vessel rupture increase
Define dementia.
An umbrella term for the effects of diseases resulting in a syndrome of effects including some mix of the following symptoms and behavioral changes:
memory loss, aphasia, agnosia, apraxia, executive function decline.
Also, agitation, mood swings, aggression, depression, sundowning, perseveration, hallucination, apathy, confusion, wandering, etc.
Define aphasia.
Inability to speak
(a-phrase-ia)
Define agnosia.
Inability to recognize faces and symbols
(a-nose-ia)
Define apraxia.
Loss of fine motor skills and ability to perform practical motor tasks (e.g. buttoning shirt, tying shoes, brushing teeth)
(a-practical-ia)
What is sundowning?
The worsening of dementia symptoms as night falls
What is the most common cause of dementia?
Alzheimer's Disease (60 - 80% of dementia cases)
Where does Alzheimer's Disease fall in the top 10 leading causes of death in the U.S.?
#6
What are some common risk factors for Alzheimer's Disease development?
Age
Gender (women make up 2/3 of cases)
Family history
Social isolation
Low educational attainment
Metabolic syndrome
How is Alzheimer's Disease diagnosed (In a definitive manner)?
Only by death after autopsy
All other diagnoses made by exclusion
What is the usual age of onset for Alzheimer's Disease?
65 and older
(Although it is important to remember that AD is NOT a part of the normal aging process)
What is the age of onset for early-onset Alzheimer's Disease?
Younger than 65 years of age
What is the main function of the parietal lobe?
Sensory interpretation and organization
What are the main lobes of the cerebrum?
Frontal
Parietal
Temporal
Occipital
What is the function of the frontal lobe?
Executive function, planning, reasoning, planned motor functions
What are the main functions of the temporal lobe?
Memory organization, auditory function
What is the main function of the occipital lobe?
Visual processing
What is the gene associated with Alzheimer's Disease (although only a small percentage, ~10% of cases, are associated with it)?
Is there a protective isoform of this gene?
APOE-E4 (Apolipoprotein-E4)
Yes, APOE-E2
What genes are associated with early-onset Alzheimer's Disease? In families in which early-onset AD is prevalent, what is the hereditary nature of the disease?
APP (Amyloid protein precursor)
PSEN1 (Presenilin-1)
PSEN2 (Presenilin-2)
Autosomal dominant (50% chance for offspring)
What are the two main pathophysiological aspects of Alzheimer's Disease? Which is intracellular (inside the cell)? Which is extracellular (outside the cell)?
Beta-amyloid plaques (extracellular)
Tau-protein tangles (intracellular) - also known as neurofibrillary tangles
How do we stop or cure Alzheimer's Disease?
There is no definitive treatment available yet
Although no definitive treatment exists, what are current recommendations around preventing or slowing Alzheimer's Disease development?
Reduce metabolic syndrome factors
Learn as much as you can (Cognitive reserve hypothesis)
Describe the cognitive reserve hypothesis.
The more social interaction, education, and other activities that stimulate the brain, the more protected an individual is against the effects of Alzheimer's Disease.
AKA more brain usage = more neural connections = more of a buffer against neuronal damage or loss
Are there any clinical tests that can help in the diagnosis of Alzheimer's Disease and other forms of dementia?
Yes, the mini-cognitive test (mini-cog) and the mini-mental-state exam (MMSE)
Describe mild, moderate, and severe Alzheimer's Disease.
Mild - Person still functions independently; mild cognitive decline; may be noticed by family and friends
Moderate - Longest stage; level of care required; sociobehavioral changes; increased cognitive impairment
Severe - Loss of ability to respond to environment; personality changes; comprehensive care-giving required; loss of awareness and physical abilities
What are the common first signs of Alzheimer's Disease?
Mild cognitive impairment and loss of short-term memory
(This leads to difficulty in separating AD from the normal cognitive decline associated with the aging process)
What is the average length of life for an individual after diagnosis with Alzheimer's Disease?
4-8 years (although this number can stretch out to up to 20 years)
What is a common cause of death in individuals with Alzheimer's Disease?
Pneumonia or other respiratory issues associated with loss of proper swallowing ability
What is the second most common type of dementia?
Lewy body dementia
Note: In our review, I said vascular dementia was 2nd. There is some debate around this topic, and for the purposes of our class, Lewy body dementia is 2nd MC. However, vascular dementia is commonly cited as 2nd MC and Lewy body as 3rd MC.
What is the main dysfunction associated with Lewy body dementia?
Abnormal protein deposits (alpha-synuclein) in the brain, somewhat similar to AD
These deposits lead to a deficiency of dopamine and can cause some Parkinsonian symptoms
What is the main dysfunction of vascular/multi-infarct dementia?
Vascular damage or defects lead to loss of sufficient blood flow to the brain and subsequent brain damage
(Basically, stroke or other vascular insults damage the brain)
Describe Creutzfeldt-Jacob Disease.
An infectious disease caused by prions (misfolded proteins) that accumulate in the brain and cause neuronal degeneration
Describe Multiple Sclerosis.
An autoimmune attack on the myelin sheath that leads to scanning speech, incontinence, decreased motor ability, fatigue, nystagmus, etc.
(Remember, Multiple Sclerosis affects the Myelin Sheath)
Describe Parkinson's disease.
Not characterized by dementia until the disease has severely progressed
Loss of dopamine-producing region of the brain (substantia nigra pars compacta in basal ganglia)
Characterized by rigidity, tremor, akinesia, shuffling walk
Describe Huntington's Disease.
A hereditary, autosomal dominant genetic mutation with an onset between 20 and 50 years of age
Characterized by loss of motor inhibition, dementia, and depression
Describe the MIND diet.
A combination of the DASH (antihypertensive) and Mediterranean diets; it is thought to decrease inflammatory and metabolic processes and thus improve cognitive function
What is the most common killer among cancers?
Lung cancer
What is the most common cancer in women?
Breast cancer
What is the most common cancer in men?
Prostate cancer
Do most women diagnosed with breast cancer have a previous family history?
No, 85% have no family history of the disease
What percentage of breast lumps are non-cancerous?
80%
What are some of the possible signs and symptoms of breast cancer besides finding a lump?
- nipple or another part of breast pulling inwards
- dimpling or puckering
- sudden discharge from a nipple
- itchy, scaly sore or rash on the nipple
- localized pain that doesn't go away
- thickening, redness or darkening of the skin on the breast or underarm area
- "peau d'orange" orange peel effect
- unusual swelling and warmth, or a change in breast size or shape.
True/False. Self-breast exams are the gold standard for breast cancer detection.
False. They are not even recommended.
What percentage of women have dense breasts?
What causes a breast to be considered dense?
In what age group is the breast typically denser?
~40%
A larger presence of fibroglandular tissue (lactiferous lobules and ducts); as opposed to adipose tissue
Younger women (as their breasts are preparing for lactation)
What is the best breast cancer detection tool we have?
Mammography (x-ray of the breast)
Is it more difficult to detect breast cancer via mammography in a dense or non-dense breast?
Is breast density related to breast size?
Dense breast tissue 'shields' the tumor from detection.
No, there is no relation.
What are some risk factors for breast cancer?
(Gender? Age? Genetics? Estrogen exposure?)
Gender - much more common in females
Age - more common as age increases
Genetics - BRCA1 and BRCA2 (BReast CAncer genes) genes
Any increase in estrogen exposure - Nulliparous, no breastfeeding, early menarche, late menopause (Estrogen stimulates breast growth)
A woman finds a lump in her breast. What are some possible causes of this lump?
A cyst - fluid-filled space
Fat necrosis - usually due to trauma
A benign tumor - fibroadenoma
A malignant tumor (cancer) - adenocarcinomas (much more common) and fibrosarcomas
Where is breast cancer more commonly found in the breast (by quadrant)?
Where in the anatomical structures of the breast is it more common (the milk lobes, the ducts, the supporting tissues)?
Upper outer quadrant (armpit area)
The ducts
Which race is most commonly diagnosed with breast cancer?
Which race most commonly dies of breast cancer?
Caucasian women
African-American women
When is breast cancer awareness month?
October
The BRCA 1 gene is associated with which types of cancer?
Breast, ovarian, and uterine cancers
The BRCA 2 gene is associated with which type of cancer?
Mainly breast cancer
What does it mean for a breast cancer to be triple-negative?
Is this a more or less dangerous form of cancer?
The breast cancer cells have no receptors for estrogen (E), progesterone (P), or human epidermal growth factor (HER-2)
This type of cancer is not responsive to hormone therapy and thus more dangerous
How much earlier can mammogram detect breast cancer than self- or clinical breast examination?
2 years
Which lymph nodes drain the breast?
The axillary lymph nodes
What is the name of the first lymph node to drain the fluid surrounding a tumor?
The Sentinel node
What are the ACS guidelines for mammography?
Annual screening for women from 45-54 years of age
Biennial screening for women ≥ 55 years of age
What are the USPSTF recommendations for mammography?
Biennial screening after 50 years of age
When should a woman begin breast cancer screening earlier than the average recommended guidelines?
When she has a higher risk
- Personal or family history
- Genetic susceptibility
- History of chest radiation (e.g. past TB patients)
Describe fibrocystic disease in the breast.
What age group does it typically present in?
Most frequent breast lesion.
Painful, multiple bilateral masses that worsen in pain and increase in size during premenstrual cycle
Most common in women aged 30-50
How can breast cancer be treated?
Depends on the extent of the disease growth.
Lymph node dissection
Lumpectomy
Mastectomy
- Simple
- Partial
- Total
- Radical Halsted
- Modified-radical
