Research published today in the British Medical Journal shows that people living in deprived areas are as susceptible to higher mortality rates today as they were a century ago. It also points out the changes in the causes of this mortality.
In the early 1900’s, respiratory and infectious diseases were the main causes of mortality. Those living in poorer areas – generally inner cities – would have been more susceptible to these disease due to a large number of factors. Poor housing quality and overcrowding would have led to a greater risk of disease, and poor air quality would have exacerbated these conditions. The absence of effective antibiotics would have meant those suffering from infections would have few options in the way of treatment, and the absence of the National Health Service meant that that any treatments that did exist might have not have been available to the poor.
As the authors note, the main causes of death have changed over the last century. The discovery of penicillin and various Clean Air Acts pushed respiratory diseases down the list of important causes of death, and the NHS means greater access to treatment. Today, deprivation is linked with higher rates of smoking and drinking, as well as a greater risk of obesity and the many health problems that come with it. This means that the main causes of death are cancer and heart disease. There are two interesting points to note about these changes in mortality. The first is that they are under the control of the individual to a much greater extent. In 1900, the poor could not afford to leave inner cities or to buy medicine from doctors; in 2000, those living in more deprived areas do have the option to eat, drink and smoke less. Educating people about the risks they face and helping them to make the necessary lifestyle changes should be straightforward compared to the public health challenges faced a hundred years ago. Progress is being made here for the population as a whole, as can be seen from the falling rates of heart disease resulting from decreased rates of smoking – but as the authors show in this article, socioeconomic differences stubbornly remain.
The second point is that the problems faced in the early 1900’s would have faced people at all ages, including children; however, although there are long-term risks from passive smoking at young ages and from childhood obesity, most of the health risks occur at older ages. The authors note the fall in infant mortality, which supports this point. However, the use in the research of standardised mortality ratios, which encapsulate mortality at all ages into a single figure, necessarily hides the detail of changes in different age groups. To an extent, this is necessary – the number of deaths in each ward might be too small to carry out meaningful analysis of changes in mortality at individual ages; however, it would be interesting to see the results of analysis considering only adult mortality. Having said this, the report still raises an interesting prospect – that those living in the most deprived areas might always suffer from higher mortality than those living in more prosperous neighbourhoods.
