Determinants of health
What factors determine health?
Health of individuals and populations is determined by a number of factors, some modifiable and some non-modifiable. Whether people are healthy or not is determined to a large extent by their circumstances and environment. Factors such as access and use of healthcare services often have less of an impact.
Factors such as age, gender, ethnicity and genes are considered non-modifiable determinants of health. Factors that can be modified include lifestyle factors (smoking, alcohol, physical activity, diet), environmental factors (geography, air and water quality), socio-economic factors (occupation, income, education) and wider societal factors (macroeconomic conditions, healthcare, sanitation). Some of these factors can be addressed at individual level while others may be addressed at group level. The ‘rainbow’ model by Dahlgren and Whitehead (Figure 19a) provides a useful model to think of these influences.
An alternative model to think about health determinants is to consider influences across the lifecourse (see Chapter 23) from prenatal period to old age.
Information on determinants of health may be available from a number of data sources (see Chapters 17, 18 and 20). However, information on the wider determinants of health such as environmental or socio-economic factors is not usually available from routine health system sources. They often require other sources such as local authority data on air quality or periodic surveys such as census data.