Week 3 - Unit 3: Managing ill health and disease Flashcards
Outline the main categories of causes of death from diseases
Traumas
Burns, car accidents, severe injury
More tissue is damaged than can be replaced
Infections
Microorganisms (bacteria, viruses, fungi, parasites)
Pathogenic destruction of normal tissue caused directly by toxins or indirectly by the growth of foreign cells in the body.
Degenerative diseases
Aging
Lack of vital nutrients (malnutrition).
More cells are lost, or more energy expended than can be replaced or repaired.
Cancerous growths
More cells are made than are needed which replaces and impairs normal tissue.
There are two contrasting approaches to medical models of health and disease, Reductionism and Holism . Describe Reductionism.
- Follows a medical model of health which is Pathogenic – suggesting diseases have a single cause and that this is what needs to be treated in order to cure a disease. - Seeks to explain the experience of ill health in terms of the material functioning of the body (anatomy and physiology). - Is the founding principle of epidemiology.
Single cause of disease
Biological / Environmental
Modern approach
Scientific research approach
Can be used for epidemiology
Can be used for development of curative treatments
There are two contrasting approaches to medical models of health and disease, Reductionism and Holism. Describe Holism.
- Diseases are said to be caused by many factors (multifactorial), which are interrelated.
- The ill individual must be treated as a whole person with a specific identity (personalised medicine approach). - This considers an individual’s lifestyle, beliefs, socioeconomic status, history and personality as causes for a disease.
Multiple causes of disease (multifactorial)
Holistic
Historic approach
Personalised medicine approach
Can be used for social studies
Can be used for development of prevention strategies (health campaigns and promotions)
What does Reductionism suggest about disease aetiology (cause) ?
Single cause for a disease
What does Holism suggest about disease aetiology (cause)?
Many causes for a disease
What are the advantages / strengths / good points about a Reductionist approach to disease?
Can be used to research how a disease develops so that we can better understand it’s pathology and why symptoms develop in the way they do.
Allows for better (more effective) treatment.
Allows for better (more accurate) diagnosis and prognosis.
Can be used to inform epidemiological studies and public health policies (i.e. microorganisms and disease – HIV and Sex / Cholera and contaminated water).
What are the disadvantages / weaknesses / bad points about a Reductionist approach to disease?
Fails to account for personal circumstances.
Difficult to attribute a single cause to many diseases (i.e. obesity and cancer)
What are the advantages / strengths / good points about a Holistic approach to disease?
Takes into account personal circumstances.
What are the disadvantages / weaknesses / bad points about a Holistic approach to disease?
Extremely varied means that the research effort needed is very extensive and complex.
Which approach to disease do you think is the best – Reductionism or Holism?
Perhaps a combination of both!
Reducing a disease to its root cause can allow science to develop targeted treatments, which are aimed specifically at this causal factor.
This may lead to more effective and curative treatments, rather than therapies which only help with reducing symptoms.
However, an illness has wider socioeconomic and environmental determinants.
Reductionism alone may not address the other factors or behaviours that led to the illness developing in the first place.
Eg: Although AIDS is caused by infection with the HIV virus (reductionism), there are many factors and events which will have led to someone becoming initially exposed to and then infected with the HIV virus (holism).
Therefore, all diseases are the result of holistic and reductionist factors.
Reductionism will enable the development of effective treatment.
Holism will enable the development of effective prevention
What are the two types of reductionism?
- Biological reductionist
- Seeks the proximal (close proximity) for what is the ultimate biological cause of a disease.
- Environmental reductionist
- Seeks the distal (at a distance) by looking at the environment (physical, economic, or social) to find the ultimate social cause of ill health.
History of Reductionism vs. Holism
Historically (prior to scientific research into specific disease aetiologies) many diseases were thought to be caused by several factors (particularly lifestyle choices) – i.e. a Holism model.
Eg: People in medieval England thought that cholera was caused by generic poor living conditions.
Eg: People in the 1980’s thought that various AIDS-related diseases (like Kaposi’s Sarcoma) were due to lifestyle choices (including promiscuity, drug use and homosexuality).
Modern advances (in scientific research for specific disease aetiologies) led the conclusion that diseases often have a single cause – i.e. a Reductionism model.
Eg: John Snow discovered that Cholera was caused by drinking dirty water (NOTE JAMES THIS IS THE WATER PUMP OUTSIDE TIMS FLAT HENCE THE JOHN SNOW PUB NEXT DOOR)
Later Louis Pasteur developed the ‘germ theory’ and was able to show that microorganisms like bacteria can cause diseases. (i.e. the dirtiness of the water was due to bacterial contamination).
Eg: By 1985, research had shown that AIDS was caused by a blood borne virus – HIV.
List two examples of single gene mutations causing disease.
Cystic Fibrosis, Huntington’s disease
List two examples of multi gene causes of disease.
Cancer, Fertility problems (ectopic pregnancy)
List one example of a chromosomal problem causing a disease.
Trisomy from non-disjunction (21 = Downs Syndrome)
Disease category: Infectious
Disease cause:Bacteria
Give examples of disease
Epithelial tissue (MRSA), Gastrointestinal tissue (E.coli), Respiratory system (TB), Sexual (Gonorrhoea)
Disease category: Infectious
Disease cause: Fungi
Give examples of disease
Epithelial (athletes foot)
Disease category: Infectious
Disease cause: Viral
Give examples of disease
Respiratory system (influenza), Immune system (HIV), Nervous system (Chicken pox), Epithelial tissue (herpes)
Disease category: Infectious
Disease cause: Parasite
Give examples of disease
Red blood cells (malaria)
Disease category: Immunological
Disease cause: Immunocompromised
Give examples of disease
AIDS (from HIV)
Disease category: Immunological
Disease cause: Allergy
Give examples of disease
Asthma
Disease category: Immunological
Disease cause: Autoimmunity
Give examples of disease
Rheumatoid arthritis, Type 1 Diabetes Mellitus, Graves disease
Disease category: Degenerative
Disease cause: Mental
Give examples of disease
Alzheimer’s disease
Disease category: Degenerative
Disease cause: Muscle
Give examples of disease
Atrophy
