Thursday November 25 2010
The health impact of retirement is still unclear
“Taking early retirement is beneficial, at least for your mental health,” BBC News has reported. The website said that a study of French national grid workers has shown that early retirement has positive benefits for mental health but makes no difference to physical illness.
Researchers studied a group of over 14,000 employees of an energy company, who retired between 1990 to 2006. In the years before retirement, participants had completed annual questionnaires about their physical health and levels of mental and physical fatigue. Retiring did not seem to have any effect on the rate of physical health problems, such as diabetes and coronary heart disease, which increased with age as expected. However, they found that fatigue significantly decreased in the year after retirement compared to the year before, especially in those with a long-term illness. Depressive symptoms also fell.
This was an interesting study that suggested that retirement may have some benefits on mental health and perceived fatigue. However, the nature of the research makes it difficult to know for sure that the benefits seen were the result of retirement, and there is still a need for similar research in other countries and populations to clarify the impact of retirement.
It should be noted that the study did not actually compare early and later retirement, as nearly all employees from the company retired before 60, meaning there were no older retirees to compare participants with.
Where did the story come from?
The study was carried out by researchers from Stockholm University; University College London; the Finnish Institute of Occupational Health; the University of Turku; Versailles Saint Quentin University in France, and the Heinrich Heine University of Dusseldorf.
It was funded by the EDF-GDF energy company and a number of international research foundations, including the UK Economic and Social Research Council, INSERM and the French National Research Agency. Individual researchers also received funding by a range of other organisations. The study was published in the peer-reviewed British Medical Journal.
The study was reported on by BBC News. The coverage was mostly accurate but the emphasis on early retirement was misleading, as the French participants studied were entitled to retire between 55 and 60 years of age, with almost all retiring before 60. The researchers were mainly looking at people’s health status before and after retirement, rather than the effects of early retirement.
The Daily Telegraph covered this research well.
What kind of research was this?
This was a cohort study assessing the way retirement may affect health. It followed a large number of people over several years and measured trends in various health outcomes. Researchers measured these various aspects of health over an average of 15 years using annual questionnaires. They also analysed data gathered before and after people retired to make comparisons of their health status during these two periods.
Previous research has suggested that retirement can have an affect on health, with some studies finding it improved health but others finding health declined after retirement. As such, there is no consensus over the impact of retirement and there is a need for clearer evidence on this issue. There is also a need for further research in this area as many countries are experiencing a demographic shift towards an older population that may require new policies towards retirement age.
The study used an appropriate design to address this type of research question. Importantly, it assessed people’s health status for some time before retirement, allowing researchers to interpret any changes seen afterwards. However, all the participants worked for a single employer and greater insight may be gained from a study involving people from a wider range of job types and working environments.
It should be noted that the study did not set out to compare people who retired early with those who retired later.
What did the research involve?
A long-term cohort of people working for Electricité de France-Gaz de France (EDF-GDF) was set up in 1989, recruiting people aged between 35 and 50. There were 14,104 participants in this particular study (11,246 man and 2858 women), all of whom retired between 1990 and 2006.
Using company records the researchers collected data on retirement date, long-term illness or disability and sickness absence. People who had retired early because of disability or poor health were excluded from the analysis (610 people) because patterns of health for people in this situation are different and would make it harder to examine the relationship between standard retirement and health.
Participants were sent questionnaires every year from 1989 to 2007. They were asked questions about physical and mental tiredness, and whether they had experienced any of a number of chronic diseases (coronary heart disease, stroke, respiratory diseases and diabetes).
The researchers also collected data on the participants’ age, sex, marital status, as well as occupation category at retirement, which was categorised as high (managers), intermediate (technical staff, line managers, administrative associate professionals) and low (clerical and manual workers). In addition, further assessment was made of depressive symptoms on four occasions during the study.
The main analysis in this study looked at the annual trend in reported mental fatigue, depression or physical fatigue over the seven years before and seven years after retirement, whenever it occurred. The researchers also performed a second analysis in which retirement age was assessed, categorised as: 54 or under, 55, or 56 and over.
What were the basic results?
The mean average retirement age of participants was 54.8 years. A total of 80% were male, and the majority belonged to higher (34%) or intermediate (54%) job grades. After taking into account the effects of retirement age, sex, occupational grade and the data collection period, the researchers found that there was no difference in the occurrence of stroke, diabetes, respiratory disease or coronary artery disease before or after retirement.
Comparing the year before with the year after retirement, they found reductions in:
- mental and physical fatigue (mental fatigue odds ratio (OR) 0.19, 95% confidence interval (CI) 0.18 to 0.21)
- physical fatigue (OR 0.27, 95% CI 0.26 to 0.30)
- and in depressive symptoms (OR 0.60, 95% CI 0.53 to 0.67)
How did the researchers interpret the results?
The researchers said that ‘the findings provide unique evidence that retirement is related to improvement in wellbeing, with little effect on chronic disease.’ They also suggest their results mean it is no longer necessary for future research to focus on how retirement may prevent chronic disease. However, they say that ‘fatigue is common among older workers’ and suggest that policy makers might need to consider the impact of this on ability to work, and consider what strategies might be necessary to reduce this problem.
The researchers also discuss the strengths and limitations of the study, and recommend that further research be carried out in other countries and work environments to see if the same associations apply to more general contexts.
This study’s strengths included its size, the fact that it monitored the same people for a number of years both before and after retirement, and the way the researchers collected measurements of health on multiple occasions. However, there were a number of limitations that should be considered when interpreting the findings:
- France has a lower retirement age than many European countries, and many of EDF-GDF’s workers are entitled to retire around the age of 55. Therefore, the findings may be different if the same kind of study was carried out in countries or environments where the retirement age was later.
- Participants in the study all worked for the same company, which is reported to have good job security and good opportunities for promotion (hence only 12% of people being of a low employment grade at retirement). Although the participants performed a variety of roles, people working in other types of jobs or different work environments may show different patterns of health before and after retirement. It is difficult, therefore, to predict how well these findings might apply to people in a wider range of job types.
- In studies of this type, it is hard to work out the extent to which the factor being investigated (retirement) is a cause of the outcome being investigated (better health) or whether the observed association is caused by some other factor.
- Employees who had retired early on health grounds were excluded from the study, so the research cannot tell us anything about the health impact of retirement on people in that situation.
- The proportion of women in this study was quite small (20%), so further research may be needed to see whether the same effects are seen in men and women.
- The study authors point out that the fact that occurrence of poor health relied on people’s own reports, means there may be an underestimation of the number of cases of some illnesses, as some might not yet have been diagnosed. They also state the method they used to measure fatigue has only been validated to a limited extent, so its reliability is not confirmed.
Overall, this is an interesting finding which suggests retirement is more important with respect to fatigue and mental health than prevention of chronic diseases such as stroke and diabetes.
However, a number of limitations in the study mean that it is hard to generalise the findings to other settings. As early retirement was not compared with later retirement (beyond age 60 years), the news source’s conclusion about early retirement being better is not warranted. As populations increase in age in many countries, further research on the health impacts of age at retirement are warranted.