Lecture 13 : Factors (3) Overview

1. Lecture 13 : Factors (3)Overview • INHERENT FACTORS • Age • Gender • Race • Blood Type • Other Genetic Factors • SOCIETAL FACTORS • Urbanisation • Social Class • Income • Occupation

2. Age And Gender • The risks of degenerative diseases increase with advancing age. It is therefore essential to take age into account when comparing areas. • Females have higher morbidity rates, but lower mortality rates. They therefore have higher life expectancy. • Given that there are only two sexes, males and females are normally studied separately. • Gender differences in mortality are not necessarily genetically determined. Females have a lower life expectancy in some countries, especially Islamic countries, suggesting that life expectancies may also be influenced by gender roles.

3. Race • Different racial groups appear to have different susceptibilities to certain diseases (e.g. skin cancer in fair skinned people, rickets in UK Asians). • It is difficult to separate the biological effects of race from the effects of social context – e.g. different racial groups in any given society tend to suffer different degrees of social deprivation. • Nevertheless, race should not be discounted as a possible contributory factor.

4. Blood Type • The susceptibility to certain diseases appears to be influenced by blood type. • Blood type is genetically inherited, and has a geography reflecting past migration patterns. • Blood types A and O dominate in the UK in Ireland. • Blood type A in the UK is more common in the areas colonised by Vikings, Angles, Saxons and Normans. Blood type O is more common in the Celtic fringe. • Blood type A in Ireland is more common in the east, type O in the west. • Blood type might account for some of the spatial variations in some diseases.

5. Blood Type And Disease

6. Type A Type O

7. Type A Type O (Source: Sean Cremin)

8. Urbanisation • Urban areas have higher SMRs than smaller towns which have higher SMRs than rural areas. • Urbanisation should be thought or as a correlate rather than a cause of health problems.

9. Social Class • Mortality rates tend to reflect differences in social class. • Overall mortality rates in the UK are much lower for people in Social Class I (professions) than Social Class V (unskilled manual). • These disparities are found for males and females, and at all ages. • The disparities are found for all the major causes of death (with the possible exception of cancer in females). They are especially marked for respiratory diseases.

12. Income • Disease mortality in the USA is correlated with income. The same is almost certainly true in the UK and Ireland, although less information is available on people’s income. • It is not clear whether income levels directly influence health or just happen to be correlated with other social class related factors which may be more important.

14. Occupation Mortality rates are influenced by occupation in tow ways: • Occuaptional accidents. Several occupations (e.g. trawler fishing, iol rig workers, coal mining, construction workers) have a much higher risk of a serious accident. • Occupational diseases. Known risks include: Hydrocarbons – higher risk of cancer Chemicals – e.g. vinyl chloride (liver cancer) Dust and fibres – e.g. coal miners (pneumonoconiosis), cotton workers (byssinosis), asbestos (asbestosis) Radiations.