Understand 2nd year medicine

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Psychology

Sex and Gender

Sex - Biological differences (e.g. hormone)
Gender - Social, cultural, psychological difference (e.g. femininity)

Leading cause of death for M&F
- M: Circulatory
- F: Cancer

Life expectancy
M - 77
F - 82

Mortality differences (Why men die earlier then women)

  • Male vulnerability (Fetus - higher risk of utero complication, SID)
  • Female robustness (Coronary heart disease: estrogen improves outcome for CHD, which is why females have a lower risk of heart disease than men until post-menopause!)
  • Social: Male gender roles encourage harmful behavior (e.g. RTA) and male with different coping mechanism (less social support -> suicide) - 75% suicides are men!!!
  • Health-related behavior: Women generally drink less, smoke less, eat heathily
  • Use of health service: Men less likely to visit GP (Stoicsm - masculinity), less cancer awareness (prostate cancer), lethal hit of diseaseFemale morelikely to visit GP: Less working hours (consult easily), diseases more chronic




Disfiguring condition and social avoidance
Disfigurement: Judgment based on social norm

Psychosocial impact
Cause: Body image (Physical and psychological perception of own body) -> Distress, difficult social functioning

Consequence
- Intrapersonal - Negative emotion (distress, embarrassment)
- Interpesonal= Difficult encounter with others
  • social pressure for ideal looks
  • felt and enacted stigma
    • Felt: fear or worry that such discrimination might occur
    • Enacted: Discrimination
  • halo effect: cognitive bias whereby the perception of one trait is influenced by the perception of another trait of that object (see as looking ugly, therefore, negative attribute... or ipod.... therefore all others must be good!)

Learned response
Phobic response: Extreme persistent irrational fear to object/situation causing anxiety

- Operant conditioning

decreases likelihood of behaviorincreases likelihood of behavior
presentedpositive punishmentpositive reinforcement
taken awaynegative punishmentnegative reinforcement

  • Continuing avoidance -> No reality testing -> No anxiety (Operant conditioning)
    • Negative Reinforcement: behavior is strengthened by the consequence of the stopping or avoiding of a negative condition.
- Modelling
- Classical conditioning - even generalize to other stimuli!
  • Xenophobia: Strangers fear (xenograft.... other species!!! allophobia - same species)
  • Agoraphobia - Fear of the fear (a fear of having panic attacks outside of place of safety)
  • Isolated phobia - mirror
    • UCS (Disfigurement) + NS (Mirror) -> UCR (anxiety)
    • CS (Mirror) -> CR (anxiety)


Altered body image: a fear-avoidance model of psycho-social difficulties following disfigurement


Neurosensory cause
- Rapid: Stimuli -> Thalamus -> Amygdala (fear)
- Evaluation: Stimuli -> Thalamus -> Cortex -> Amygdala
- Memory to elicit fear!: Stimuli -> Thalamus -> Cortex -> Hippocampus -> Amygdala

Factors affecting adjustment

- Age - puberty!

- Sex - female concern more (male sees disfigurement as victory)

- Visibility

- Severity - NO DIRECT CORRELATION!


Treatment
- Societies - changing faces
- REBT (rational emotive behavioral therapy)
  • A - activating events - happening around the person
  • B - beliefs - determines C when A happens
  • C - Consequences
  • D - Dispute (therapist change the person's beliefs (B) toward the event (A) so that the event may have different consequences (C) toward the person. By changing the beliefs, the person may now have effective new thinking (E) to replace the previous negative reaction toward the event.
  • E - Effective new way of thinking
- Systematic desensitization (graded exposure): Reality testing - decrease in response to stimuli after repeated exposure to the stimuli over time

Repeated exposure generates a new memory for safety



- Flooding
- Modelling
- Anxiety mgm
- Social skills training

Psychosocial of cancer

Personality
- Type A: Strive for success, focused, inpatient -> develop heart disease
- Type B: Passive
- Type C: Suppress negative emotion, cooperative, accept external authority (accept their fate easily, no fighting spirit) -> cancer-prone

Hardiness: transform stressful living changes into optimistic ones (see things as a challenge)

Life event/stressor correlates with cancer
- Mice: Shaking the cage
- Death of a close friend
- Cortisol/adrenaline

Factors affecting whether one attends screening
- Anxiety
- Dispositional optimism
- Confidence about performing self-exam
- Health locus of control - if they are responsible for the change, they will attend
- If think high risk: Health belief model (Hillary believes proofreading S S C - benefit/cost, health motivation, severity, susceptiability, cues to action)




(reasoned... maybe..) MOBE: Motivations to comply, opinion of what others will think, beliefs of behavior, evaluation of behavior

Response to diagnosis
- Grief response (Kubler and Ross)


- Shontz (1975): Shock (detachment), encounter (extremely intense period of feeling helplessness, panic), retreat (denial)
- Coping
  • Engagement: Acknowledge, prob-solving, less depression
  • Disengagement - Avoidance (apathy)

Response to treatment
- Patient tend to choose surgery > chemo (perceive surgery as more effective)
- Anticipatory nausea: nausea and/or vomiting occurring before chemo in response to a conditioned stimuli (e.g.  smells, sights, and sound of the treatment room)



Alternate grief response: BEREAVEMENT

Widow - Woman
Widower - Man

Kubler-Ross: Denial -> Anger -> Bargain -> Depression -> acceptance

Parkes (1975) RASLIPC
Realization (Denial -> Acceptance) -> Alarm reaction  -> Urge to search for the lost person -> Anger/guilt -> Feeling of internal loss of self -> Identification phenomenon (adopt manners of lost person) -> Pathological variant of grief -> Counselling

Worden (1991): Resolution of grief and forming new relationship - awam  (unstable w to stable m)
  1. Accept reality of loss
  2. Work through pain
  3. Adjust to new env.
  4. Move on with life

Strobe and Shut (1998): Dual process (oscillate between loss- and restoration-orientated work)
Breaking ties (Loss) vs New relationship (Restoration)
Grief work (loss) vs Doing new things (Restoration)

s and s... (strobe and shut) two things... loss and orientation

LER



Factors influencing grieving
  • Relationship with deceased
  • Previous exp. of loss
  • Social suport
  • Prevoius life crisis
  • Religion /culture
  • Age/sex (F: Overt i.e. observable distress, seek help)
  • Personality
  • Nature of death: Violent/untimely


Pathological grief reaction (Worden)
- Exaggerated: Overwhelmed and develop psychiatric disorder
- Chronic: Normal grief continues for excessive period
- Delayed: Rxn occur some time after death
- Masked: Experience physical symptoms which at first don’t seem to be related to loss

Diagnostic for complicated grief i.e. pathological (Hawton)
- For at least 6 months
  • Life meaningless
  • Disbelief
  • Irritable
  • Assuming behavior of deceased
  • Feeling that part of oneself is gone

Grief and poor health (increased risk of death in 1st year!)
- Lifestyle - alcohol, smoking after spouse’s death
- Stress
- Depression (1/4 widow show in 1st year)

Bereavement support
  • NICE 3 tiers
  1. Provide information about local service

  2. Specialist service if high risk
  • GP
  • Bereavement counselling

Fishbone analysis (all M’s... material, method, machine, measurement, marine - environment, huMan) 6



Poverty and Health

Absolute poverty - lack of basic life necessities, living on <1.25 USD /day
Relative poverty - Poverty by reference to overall standard of living in society

Blame the victim: Poor is responsible for their poverty

Blame the system: Poor due to structural force in society

Social exclusion (Marginalization): Deny resources, rights, services
- Consequences of social exclusion: Live in unsafe env., lose hope

Socioeconomic status
1 - Highest, 8 - Lowest

Childhood & Poverty
- Poor cognition
- Die from accident
- Exposure to crime, drug

Babies and Poverty
- Learn / affected by negative health behaviors of parent(s): Smoking
- Less likely to be breastfed
- Higher IMR (die in first year of life per 1000 born)

Homeless people

Official homeless - Registered
Unofficial homeless - Sleep on streets


Why they are homeless:
Unemployment, poverty, gov't conflict, mental disorder (service not available or deinstitutionalization from long-stay psychiatric hospitals to community mental health service), no affordable housing (rising house prices!), prison release, disaster, forced eviction (minimal compensation from gov't to make way for high rise buildings), mortgage foreclosure

Poverty in UK (Household income <60% of median income)
  • 1/5th of population in poverty
  • London higher proportion of poverty
  • Higher proportion in relative poverty than most other EU countries

Dealing with poverty:
- Duty of local authority to provide advice for those at risk / currently homeless
- Inquiry to see whether accommodation and assistance is owed
-  "Interim accommodation" for those pending a final decision

“Priority need"  e.g. pregnant > dependent children > etc..


Asylum seeker: Fear of being persecuted for reasons of race, religion, political opinion etc... in their country
- Largest source: Iraq, Burma (Myanmar), Afghan

UK is signatory (bound by legal doc.) to the UN Convention Relating to the Status of Refugees
- Not to return refugees to the place where they would face persecution.
- Many from colonies in British Empire (India, Pakistan, HK etc.), EU member states (EU’s 4 freedoms - goods, capital, services and PEOPLE)

Prone to
- Wounds or starvation
- PTSD or depression.
- Human rights violations, child labor, mental and physical trauma/torture, violence-related trauma, and sexual exploitation, especially of children, are not entirely unknown.

Seeing and Perception

Seeing: Raw stimuli
Perception: Combine raw stimuli with previous knowledge to form an interpretation
  1. Selection: Of one angle
  2. Attention
    1. of data
  3. Organization
    1. contours

Agnosia (Loss of knowledge)
  • Visual: See but can’t perceive
  • Apperceptive: Can’t copy image
  • Associate: Can’t make sense of the object they see
  • Prospopagnosia: Can’t recognize face

Organization: Gestalt law
Whole is greater than sum of its parts: Miss information that don’t make sense



Bottom-up: Analyse cues to match template
Top-down: Construction Based on context to form representation

Perceptual bias: Predisposition to interpret a stimuli a certain way
  • Instruction: e.g. cervical smear - be careful -> higher false positive
  • Perceptual set - expectation (if say painful, report painful)
  • Motivation (if hungry, see food cues)


Pain
  • Acute: Limiting
  • Chronic: Alter sense of self (find ways to shape life - “pain person”)
    • often no identificable cause
    • fluctuation between hope and despair
      • don’t think of pain when background (e.g. win lottery)
      • pain come to foreground

Therefore acute and chronic pain patients have different expectionations

OA: Patients see as normal for age/job → Normalize pain → Don’t consult (see it as a biography of their life)

Treatment to fit their identity (e.g. to be a grandad) and ALSO
  • how they adapted?
  • if don’t listen to patient to patient → don’t take med
    • fear of dependence, sfx
    • concerns
Depression
Based on history
"SIGECAPS - D"

S = Sleep disturbance,
I = Interest (diminished),
G = Guilt or feeling worthless,
E = Energy (loss),
C = Concentration difficulties or indecisiveness,
A = Appetite abnormality or weight change,
P = Psychomotor retardation or agitation,
S = Suicide or death (acts or thoughts of).
D = Depressed mood

Often associated with substance misuse!

One must remember that to call it a depression the duration has to be of 15 days

 

Economics & Epidemiology

Health Economics

Because of scarcity -> there is Opportunity cost (next best use of resource)

Law of (Consumers) Demand - inverse proportional
The law of demand states that, if all other factors remain equal, the higher the price of a good, the less people will demand that good.

The amount of a good that buyers purchase at a higher price is less because as the price of a good goes up, the opportunity cost of buying that good also goes up -> people will avoid buying it.


A, B and C are points on the demand curve. So, at point A, the quantity demanded will be Q1 and the price will be P1, and so on. The demand relationship curve illustrates the negative relationship between price and quantity demanded


Law of (Producers) Supply - directly proportional


Higher the price, the higher the quantity supplied. Producers supply more at a higher price because selling a higher quantity at a higher price increases revenue.

Perfect economy = Equilibrium


When supply and demand are equal. At this point, the allocation of goods is at its most efficient because the amount of goods being supplied is exactly the same as the amount of goods being demanded.

A market economy
Balances supply and demand at the most efficient point

  • If supply increases/demand falls, price falls, and suppliers reduce production
  • If supply decreases/demand increases, price rises and suppliers increase production

Price = signal

No/imperfect market -> No price signal (e.g. central planned economy)

Imperfect market

A market where information is not quickly disclosed to all participants in it and where the matching of buyers and sellers isn't immediate.

1) Monopoly
- Large supplier

2) Monopsony: A market similar to a monopoly except that a large buyer not seller controls a large proportion of the market and drives the prices down. They had such power buying grapes from growers, that sellers had no choice but to agree to their terms. e.g. PCT purchases

2) Information assymetry
- one party in a transaction has more or superior information compared to another. This often happens in transactions where the seller knows more than the buyer (Patient doesn’t know, thus require agency - e.g. GP

3) Public good: a good that is non-rivalrous and non-excludable.
  • Non-rivalry: consumption of the good by one individual does not reduce availability of the good for consumption by others
  • Non-excludability that no one can be excluded from using the good

4) Externality: A cost or benefit to someone outside the transaction, for example a change in a hospital might produce an externality in terms of problems local residents have in parking. Pollution is a classic externality.

5) Moral hazard:  tendency for people to consume more of something if they don’t have to bear the cost (classic example is claiming under an insurance policy, especially if there is no no-claims bonus)

West midlands SHA -> North staffordshire PCT


Types of economic analysis

- Cost-benefit: monetary value to outcomes.
- Cost-effectiveness:  unidimensional index of outcome (e.g. HbA1c in DM)
  • Cost-utility: A special case of cost-effectiveness
  • Ratio between the cost of intervention and the benefit it produces in terms of the number of years lived in full health. (QALYS)
    • Intervention A allows a patient to live for three additional years than if no intervention had taken place, but only with a quality of life weight of 0.6, then the intervention confers 3 * 0.6 = 1.8 QALYs to the patient. If intervention B confers two extra years of life at a quality of life weight of 0.75, then it confers an additional 1.5 QALYs to the patient. The net benefit of intervention A over intervention B is therefore 1.8 - 1.5 = 0.3 QALYs.

Approaches for equity

Fair innings: those who have lived to a certain age have already lived most of their expected lifespan (i.e. have had a 'fair innings') and that priority should be given to those who have not yet lived so long. That is, there is greater duty to prevent the death of the young than the old.

Rawls: A Theory of Justice - All social primary goods and the bases of self-respect - are to be distributed equally unless an unequal distribution of any or all of these goods is to the advantage of the least favored. (i.e. greatest benefit of the least-advantaged members of society)

Rule of rescue: the sense of immediate duty that people feel towards those who present themselves to a health service with a serious condition

Utility maximization: Utility (relative satisfaction) to be maximized within society, aiming for "the greatest happiness for the greatest number of people"

Equity-Efficiency Tradeoff - perceived tradeoff between the equity (financial capital) and efficiency (future efficiency in the goods/services production) of a given economy. This theory asserts that, in order for a nation to become wealthier, it must save its equity. However, these additional savings will hurt the development of more efficient production in the future.

Grossman model

Individuals invest in themselves (through either education or health) to increase their productivity. To undertake these investments, individuals need money.

Health, therefore, is demanded mainly for two reasons, consumption (utilize health) and investment (determines total time available).



Epidemiology: Study of distributions (person, place, time) in health

Ratio: x/y
Proportion: x / x+y
- in this case top is numerator and bottom is DENOMINATOR

Rates are absolute


Embryo up to week 8
Fetus: 20 weeks and onwards viable
Baby: After fetus is born

Perinatal death = a fetus + early neonatal + late neonatal

  • Fetus: after 20 weeks (i.e. stillbirth)
  • Early neonate: Live-born within 7 days of life
  • Late neonate: 7 days - 28 days

Perinatal mortality rate

- the sum of fetal deaths (stillbirths) and neonatal deaths per 1000 births.


Postneonatal (i.e. infant): remaining 11 months of first year or life  (i.e. beginning of 2nd months to end of 12th month)



Infant mortality rate (time is not important here............)
- No. of babies dying <1 year old  / No. of live birth per 1000

Incidence: ABSOLUTE Risk of developing a new condition within a specified period
No. of new cases / Pop. @ risk

Prevalence (extent): PROPORTION Total cases in the population/No. of people in the population. It is used as an estimate of how common a condition is within a population over a certain period of time.

For a disease that takes long to cure and spread widely in 2003 but arrested in 2003 (e.g. HIV)

2002: High incidence and high prevalence
2003: Low incidence and high prevalence (many existing cases but not many new ones)

Conversely, a disease that is easily transmitted but has a short duration (e.g. cold)

2002: High incidence short prevalence

Therefore, incidence is used when talking about diseases of short duration, but prevalence if long-lasting.

When studying the etiology of a disease, it is better to analyse incidence (absolute risk)rather than prevalence (proportion) , since prevalence mixes in the duration of a condition, rather than measuring risk.

Standardization
- Compare health outcomes after controlling age and sex differences between 2 populations

Direct
  • (ABSOLUTE) Rate: If Local had same age, sex structure as the standard (EU)
  • Used when the local pop. is large enough

Indirect
  • Ratio: Observed / Expected
    • Used when pop. is small, esp. when direct age/sex standardization is NOT APPROPRIATE because of dissimilar distributions
    • Standardized mortality ratio (SMR): Local Observed deaths / Standard Expected death
      • An SMR greater than 1.0 indicates that there were "excess deaths" compared to what was expected.
      • SMR is a measure of relative risk

Death rates
- Not entirely useful
Does not account for cause of death: e.g. UK higher than Ireland because older pop.

WHO Health gain classification
  1. Years to life - living longer
  2. Life to years - given level of health to get the most out of life (e.g. wheelchair - using public transport
  3. Health to life - not having disease

Types of health measure
- Mortality
- Morbidity
- Well-being: SF-36

General fertility rate: No. of live birth/year/thousand women between 15-44 (fertile yrs)
Total fertility rate (TFR): Each women’s expected no. of babies over her lifetime



Pre-test probability is the prevalence i.e. (4/20 = 4/16+4), thus is a proportion. (Proportion: x / x+y)

Sensitivity: how good the test is at testing present (RULE OUT - high sensitivity test i.e. little/no false negative, all negatives must be true neg.)
Proportion that has disease (True pos/ True pos +False neg)
i.e. correctly identified with disease / all with disease
If no false negative: sensitivty is 1!
¾ = 75%

Specificity: how good the test is at testing absence (RULE IN - if high specficity and a negative result, means must be it!)
Proportion of those that don’t have disease (true negative  / Fals pos+true neg)
i.e. correct identified w/o disease / those w/o disease
15/16

If 100 patients known to have a disease were tested, and 43 test positive, then the test has 43% sensitivity. (RULE OUT)

If 100 with no disease are tested and 96 return a negative result, then the test has 96% specificity. (RULE IN)

More test-related...
1) Positive predictive value: How likely s/o with positive test has the condition
Those identified as having disease / all test positive
true pos / true pos + false pos

¾ = 75%
2) Negative predictive value: how likely s/o with negative test does not have condition
Those identified correctly w/o disease / all test negative
true neg / true neg + false neg





Relationship between prevalence and predictive value

As prev falls(total cases i.e. true pos + false neg /popln.) e.g. more ppl?
- ppv (true pos / true pos + false pos)  falls (more likely pos test is false pos)
- NPV (true neg / true neg + false neg) is high.

As prev increases, ppv increases (more likely pos test is true pos.)

Rule in and out

To rule out a diagnosis (i.e. high NPV - true neg / true neg+false neg) use a test with high sensitivity (test identified w/ disease / all w/ disease)
- Has least false negative -> highest sensitivity (true pos / true pos + false neg) - most positives would be true pos.
If a test has high sensitivity, a negative result suggests the absence of disease!

To Rule in a diagnosis (i.e. high PPV - true pos / true pos+false pos): Use test with high specificity (test identified w/o disease / all w/o disease)
- a test with least false positives has highest specificity (true negative / true neg+false pos) - most negatives would be true neg.
If a test has high specificity, a negative result suggests the presence of disease!

If 100 patients known to have a disease were tested, and 43 test positive, then the test has 43% sensitivity. (RULE OUT)
- A high sensitive test (true pos / true pos + false neg) , so a negative result should be reassuring (the disease tested for is absent).

If 100 with no disease are tested and 96 return a negative result, then the test has 96% specificity. (RULE IN)
- A high specific test (true negative / true neg+false pos) will not give a false positive (if it appears positive, it must be a true positive!)

A highly SPecific test, when Positive, rules IN disease (SP-P-IN), and a highly 'SeNsitive' test, when Negative rules OUT disease (SN-N-OUT).


100%Sesntivity --------------------------------------------------- 100%Specificity



Framingham score: Risk prediction for heart diseases

With regards to the test...
Did - True positive, false positive
Did not  - true negative, false negative

About the test... not the disease!!!!


Green one

False negative do not develop (Sensitivity = true pos / true pos+false neg)


Focus on the yellow one!

False positive (tested yes but do not have) Do not develop (Specific = true neg / true neg+fals pos)... if

Focus on green one


Rose hypothesis


Shifting BP is better than targeting high BP people

Majority of disease is due to larger pop. of low moderate risk and only MINORITY due to high risk