Study finds North-South divide in UK life expectancy

"England's richest people 'live eight years longer than the country's poorest'," The Independent reports. 

A major new study has found a significant difference in life expectancy of the richer South East England compared to the poorer North.

The researchers found that overall life expectancy increased by more than five years from 1990 to 2013, from 75.9 to 81.3 years. The gap in mortality between men and women has also decreased, which is encouraging. 

However, more deprived areas have failed to catch up with less deprived areas, with a difference of more than eight years. Areas of deprivation were mainly located in the North, the Midlands and some areas of London.

There is also evidence that, while there has been an overall decline in mortality, there has been less of a reduction in the length of time people are living in poor health with chronic illness or disability. 

The study has shown where improvements have been made and areas that would benefit from more attention. Many of the leading causes of death are preventable through an active and healthy lifestyle and a good diet.

Where did the story come from?

The study was carried out by researchers from a number of institutions, including Public Health England and the London School of Hygiene and Tropical Medicine. 

Funding was primarily provided by the Bill & Melinda Gates Foundation. Additional funding for the study was provided by Public Health England.

The study was published in the peer-reviewed medical journal The Lancet on an open-access basis, so it is free to read online or download as a PDF.

The study has been widely reported in the UK media. Reporting of the study was accurate for all sources.

What kind of research was this?

This study used data from the Global Burden of Disease (GBD) 2013 study to analyse the burden of diseases and injuries in England, by region and within each region by level of deprivation. GBD is an ongoing global collaboration looking at trends in diseases that can cause death or disability.

Researchers compared this data with earlier years, going back to 1990. This method is able to look at large amounts of data for a long period to draw overall patterns and conclusions. However, it cannot provide definite answers as to why mortality or illness rates are as they currently stand, or why they have changed.

What did the research involve?

This study used data from the GBD 2013 study on causes of death, disease, and injury incidence and prevalence, as well as years lived with disability (YLDs) and disability-adjusted life-years (DALYs). DALYs is a term used by epidemiologists to measure the number of "healthy years" lost due to ill health, disability or early death.

Researchers looked at the following countries:

• England
• UK
• The first 15 EU members (excluding the UK)
• Australia
• Canada
• Norway
• US

The GBD 2013 study also provides independent and overlapping attributable risk for five tiers of risk factors:

1. All GBD risks combined.
2. Three large categories of metabolic, behavioural, and environmental and occupational risks.
3. Single risks, such as high blood pressure, and risk clusters, such as child and maternal under-nutrition or air pollution.
4. Single risks within such clusters, such as vitamin A deficiency or household air pollution.
5. Individual occupational exposure to cancer-causing substances or the division of childhood underweight into stunting, underweight and wasting.

The Index of Multiple Deprivation (IMD-2010) was used to measure deprivation. This is a government study that aimed to assess levels of deprivation in areas of the UK. 

Mortality data for the period 1990 to 2012 was obtained from the Office for National Statistics and split into regional and deprivations groups based on postcode.

What were the basic results?

The study found that from 1990 to 2013, life expectancy from birth in England increased by 5.4 years (95% confidence interval [CI] 5.0 to 5.8) from 75.9 years (95% CI 75.9 to 76.0) to 81.3 years (95% CI 80.9 to 81.7). A greater improvement in life expectancy gains was seen for men than for women.

Rates of age-standardised years of life lost (YLLs) reduced by 41.1%, which indicates a greater reduction in premature mortality compared with overall mortality. A small decrease was seen for age-standardised YLDs. DALYs were reduced by 23.8%.

The range in life expectancy across deprivation areas has stayed the same for men since 1990 – an 8.2 year difference between the least and most deprived areas. However, for women, the deprivation differences decreased from 7.2 years in 1990 to 6.9 years in 2013. In 2013, the leading cause of YLLs was heart disease, and the leading cause of DALYs was low back and neck pain. Leading behavioural risk factors were suboptimal diet and tobacco.

Overall, England ranked better than the other UK countries and was found to be the EU country with one of the largest gains in life expectancy among men (6.4 years). This is less than Luxembourg, but the same as Finland. 

All English regions except for South West England, gained at least six years, which is equal to or greater than all comparator countries except Austria, Finland, Ireland, Germany and Luxembourg. 

Among women, the increase in life expectancy in England overall was 4.4 years, which is equal to or in excess of all countries except Finland, Germany, Ireland, Luxembourg and Portugal.

How did the researchers interpret the results?

The researchers conclude that, "Health in England is improving, although substantial opportunities exist for further reductions in the burden of preventable disease. The gap in mortality rates between men and women has reduced, but marked health inequalities between the least deprived and most deprived areas remain". 

They go on to say that policies must address the causes of ill health and premature mortality. Action is needed to reduce risk exposures, support healthy behaviours, alleviate the severity of chronic disabling disorders, and mitigate the effects of socioeconomic deprivation.

Conclusion

This study used data to analyse the burden of disease and injury in England, and within each English region by level of deprivation. This was compared with the remaining constituent countries of the UK and with other comparable countries.

The researchers found an overall increase in life expectancy from 1990 to 2013. The decreased mortality gap between men and women is also encouraging. However, the inequality of life expectancy across regions of England has not improved. Those in more deprived areas have not yet reached the life expectancy of the less deprived in 1990.

Despite the overall decline in mortality, this has not been matched by a similar decline in the number of years people are living in poor health or with chronic illness.

The authors suggest the main reasons for improvement in life expectancy are reductions in: 

• cardiovascular disease
• cancer mortality
• chronic respiratory disease
• road injuries

However, they report that conditions still having a negative impact on life expectancy include:

• cirrhosis of the liver (related to alcoholic liver disease)
• mental disorders
• substance use

Strengths of this study are the large amount of population data used and the long follow-up period. Some limitations are that data was not available for some diseases or by specific deprivation level. The relative level of deprivation of an area may also have changed since the measurement tool was created, and the cross-country comparisons may not be as straightforward as presented.

The findings have indicated areas where improvement has been made and possible areas that would benefit from more attention.

Though not all diseases are preventable, poor health can be caused by risk factors such as poor diet, low levels of physical activity, smoking and alcohol consumption.