Wednesday June 4 2014
Frail older people are more vulnerable to infection
"Centenarians have found a way to beat the common diseases of old age," BBC News reports. A UK study found that the over-100s are less likely to die of diseases associated with lifestyle and more likely to die from infections such as pneumonia.
Over a 10-year period, researchers examined trends in outcomes for centenarians in England, comparing them with younger elderly people who died in their 80s.
They had a particular interest in place of death because this can have an impact on health budgets, as dying in a hospital is often associated with higher costs.
This was intended to inform service provision for centenarians because of the increasing number of people worldwide who are now living beyond the age of 100, which could be as high as around 3 million by 2050.
The study found that centenarians were less likely to die of what are known as non-communicable diseases. These are diseases such as cancer or heart disease that can be caused by unhealthy lifestyle choices, including smoking, obesity and lack of exercise.
But centenarians were found to be more likely to die of diseases that many of us assume are a thing of the past, such as pneumonia.
Ultimately, these findings will be a useful tool for planning future services for people in this age group.
Where did the story come from?
The study was carried out by researchers from Kings College London and Sussex Community NHS Trust, and was funded by the National Institute for Health Research.
It was published in the peer-reviewed open access journal, PLOS Medicine, so it is freely available to read online.
The story was covered appropriately by both BBC News and the Daily Mail.
The Daily Express claims that the findings of the study amount to a "scandal". It is hard to see how the newspaper can justify such emotive language.
If anything, the fact that more people are living over 100 is testament to the success of the NHS in improving public health.
What kind of research was this?
This was a population-based retrospective observational study comparing place of death and other characteristics.
These characteristics included cause of death for people aged 100 years or older in comparison to a group of younger elderly people over a 10-year period in England.
In an observational study, researchers simply observe groups of people without changing their exposures or circumstances.
A retrospective study relies on data collected in the past, such as from national databases, as was the case in this study. Data collected retrospectively may not be as reliable as data collected prospectively.
However, as the data collected in this study came from national databases, the information is likely to be fairly accurate.
What did the research involve?
The researchers included individuals aged 100 years or older at the time of their death who died in England between 2001 and 2010. The only causes of death excluded were accident or violence.
This group was compared with individuals aged 80 to 99 years in the same time period.
The main outcome the researchers were interested in was place of death, which was grouped into five categories:
- nursing home (defined as providing 24-hour long-term care with nursing)
- residential care home (defined as providing 24-hour long-term care without nursing)
The researchers used death registration data from England's Office for National Statistics (ONS) from 2001 to 2010 to obtain information about each individual's place of death.
The database was also used to gather information on each person's:
- marital status
- usual residence
- year of death
- underlying cause of death
- contributing cause(s) of death
They linked this data with local data on deprivation, settlement type (for instance, urban, town or village), and care home bed capacity. Statistical methods were used to analyse the data.
What were the basic results?
There were 35,867 individuals included in this study who were aged 100 years or older (range 100 to 115 years). Most were women (86.75) and most were widowed (85.0%).
The number of centenarian deaths per year in England increased by 56% in 10 years from 2,823 in 2001 to 4,393 in 2010.
The main findings of the study were:
- most centenarians died in a care home, with 26.7% dying in a nursing home (95% confidence interval [CI] 26.3% to 27.2%) and 34.5% dying in a residential care home (95% CI 34.0% to 35.0%)
- dying in a hospital was the next most common place of death (27.2%, 95% CI 26.7% to 27.6%)
- the proportion of deaths in nursing homes (-0.36% annually) decreased over 10 years, while there was little change in hospital deaths (0.25% annually)
Centenarians were more likely to die of:
- pneumonia (17.7%, 95% CI 17.3% to 18.1%) compared with people aged 80 to 84 years (6.0%, 95% CI 5.9% to 6.0%)
- old age/frailty (28.1%, 95% CI 27.6% to 28.5%) compared with people aged 80 to 84 years (0.9%, 95% CI 0.9% to 0.9%)
Centenarians were less likely to die from:
- cancer (4.4%, 95% CI 4.2% to 4.6%) compared with people aged 80 to 84 years (24.5%, 95% CI 24.6% to 25.4%)
- heart disease (8.6%, 95% CI 8.3% to 8.9%) compared with people aged 80 to 84 years (19.0%, 95% CI 18.9% to 19.0%)
More care home beds being available per 1,000 people was associated with fewer deaths in hospital.
How did the researchers interpret the results?
The researchers concluded that centenarians are more likely to have their cause of death certified as pneumonia and frailty, and were less likely to die from cancer or heart disease, compared with younger elderly patients.
They said that reducing reliance on hospital care at the end of life requires recognition of centenarians' increased likelihood to "acute" decline, notably from pneumonia.
They recommend that wider provision of anticipatory care is introduced to enable people to remain in their usual residence, as well as increasing care home bed capacity.
This study provides useful information on the place and cause of death of people who live to be 100 years or older compared with a younger elderly population in England. It also provides useful information on trends that have occurred over a 10-year period.
The study's strengths include the large sample of centenarians involved in the research based on data from national registries, which is likely to be reliable.
However, death certificates do not contain information on people's preferences for care in the period before death, so we cannot use the results of this study to draw conclusions about what kind of care this group prefers at the end of life.
Other limitations of this study include that many deaths are classified as being the result of "old age", which may reflect diagnostic uncertainty or limited medical investigations.
The researchers say that certifying death as old age limits the interpretation of the cause of death and therefore the guidance of health services.
But the fact that people who died over the age of 100 were less likely to die from cancer and heart disease than people who died in their 80s is perhaps not so surprising.
Given that these people have lived to such an age suggests that they have not developed these conditions, or if they did they were not associated with mortality.
This may be the result of a wide variety of genetic, socioeconomic, health and lifestyle factors, so this study cannot provide us with any answers about the secret to living beyond the age of 100.
But adopting well-established lifestyle habits such as having a healthy diet, avoiding smoking, taking regular exercise and trying to achieve or maintain a healthy weight certainly won't hurt.
Primarily, these findings will be a useful tool in planning future services for these older populations.
Analysis by Bazian. Edited by NHS Choices. Follow Behind the Headlines on Twitter. Join the Healthy Evidence forum.