Foundations in Medicine

بسم الله الرحمن الرحيم

Foundations in Medicine Lec - 2-

Health and disease lie along a continuum , and there is no single cut - off point.

Positive Health Better Health Freedom from sickness
Unrecognized sickness Mild sickness Sever sickness Death.
“The Health - Sickness Spectrum”

Spectrum of Health

Determinants of health:-


1.Heredity.2.Environment.3.Life - Style.4.Socio - economic conditions.5.Health and family welfare services.6.Other factors e.g. food , agriculture,education,industry,…..etc.

((Concept of Disease))

Definitions :-
Disease is a condition in which body health is impaired , a departure from a state of health , an alteration of the human body interrupting the performance of vital functions.(Webster).

Responsibility for Health:-

1.Individual responsibility . 2.Community responsibility. 3.State responsibility. 4.International responsibility.

Disease is a maladjustment of the human organism to the environment (Ecological).

Disease is a social phenomenon , occurring in all societies and defined and fought in terms of the particular cultural forces prevalent in the society.(Sociological definition).


Disease is a condition of the body or some part or organ of the body in which its functions are disrupted or deranged (Dictionary).


Disease is just the opposite of health I.e any deviation from normal functioning or state of complete physical or mental well - being , since health and disease are mutually exclusive.



All the above mentioned definitions are inadequate.since they do not give a criterion by which can decide when a disease state beings , nor lend themselves to disease measurement.


It signifies the way in which a disease evolves overtime from the earliest stage of its pre pathogenesis phase to its termination as recovery , disability or death, in the absence of treatment or prevention.
Pre pathogenesis phase I.e. before entry of agent to human potentially , we are all in the pre pathogenesis phase of many diseases.

(Natural history of Disease)

It is a complex interaction between man , an agent ( or cause ) and the environment.

Final disease outcome

Pathogenesis phase is that which beings by the entry of disease agent in a susceptible human host.


a.Clinical or sub clinical. b.Typical or atypical. c. Carrier with or without clinical disease.

Agent

Environment
Epidemiological Triad

Host

Classification of disease agents:-
1.Biological agents living agents of disease.2.Nutritional agents excess or deficiency.3.Physical agents excessive heat or radiation exposure.

The interaction of these three factors will initiate a disease process.

Disease agent:-A substances ,living or non living, or a force, tangible or intangible , the excessive presence or relative lack of which may initiate or perpetuate a disease process.

6.Absence or insufficiency or excess of a factor necessary for health:-

a.Chemical hormones. b.Nutrient. c.Lack of structure Thymus. d.Lack of part of structure Cardiac defects.



4.Chemical agents a. endogenous uraemia ,jundice  b. exogenous allergens, insecticides

5.Mechanical agents chronic friction, sprain or dislocation.

e.Chromosomal Mongolism.f. Immunological Agama - globulinaemia.g.Social agents Drug abuse,alcoholism.


Host factors : it include:- 1.Demographic characteristics. 2.Biological characteristics. 3.Social and economic characteristics. 4.Lifestyle factors.


1.An attribute or exposure that is significantly associated with the development of a disease.
2.A determinant that can be modified by intervention, thereby reducing the possibility of occurrence of a disease or other specified outcomes.


Environmental Factors : it include:-1.Micro - environment.2.Macro - environment.A.Physical environment.B.Biological environment.C.Psychological environment.

Meanings of Risk factors

Risk factors are observable or identifiable prior to event they predict.

Risk factors are either:-


Risk factors are often suggestive, but absolute proof of cause and effect is usually lacking.


1.Truly causative e.g. smoking and lung cancer. 2.Merely contributary to undesired outcome e.g. physical inactivity. 3.Predictive only in a statistical sense.e.g. illiteracy and perinatal mortality.


Risk factors are of two types:-A.Modifiable e.g. hypertension.B.Un- modifiable e.g. age,sex,race,….etc.


Risk group = Target group. Biological situation. According to Physical situation. Socio - cultural situation.

Pre - symptomatic

symptomatic
Physician see
Physician doesn't see
(( Ice berg phenomenon of Disease))

The End