Suicide six times more likely in chronic fatigue syndrome patients compared to general population
People diagnosed with chronic fatigue syndrome (CFS) are more likely to die by suicide than the general population, but overall mortality rates for people with CFS are comparable to the general population, according to a new study from researchers at the Institute of Psychiatry, Psychology & Neuroscience at King's College London.
CFS, sometimes referred to as myalgic encephelitis (ME), is a serious disorder in which patients experience persistent fatigue, which can lead to long-term disability if left untreated.
The study, published in The Lancet, used sophisticated data-mining techniques to analyse the medical records of over 2000 people diagnosed with CFS accessing the national research and treatment service for chronic fatigue at South London and Maudsley NHS Foundation Trust and King's College London. It is the largest ever analysis of the causes of death in people with CFS, and the first to suggest that people with CFS may be at an increased risk of suicide.
The study was funded by the National Institute for Health Research (NIHR) Biomedical Research Centre at South London and Maudsley NHS Foundation Trust and King's College London. Dr Emmert Roberts, the study's lead author, holds a NIHR Academic Clinical Fellowship.
During the seven year study period (2007 – 2013), 17 patients in total died – eight died from cancer, five from suicide, and four from other causes. The researchers compared these mortality rates to the population data from England and Wales from the Office of National Statistics, matched for gender and age.
The results showed that there was no significant difference in the overall rate of deaths from all causes between people with a CFS diagnosis and the general population; nor was there any difference in the rate of deaths caused by cancer.
However, based on the suicide rate in the general population of England and Wales, less than one death by suicide would be expected in a study population of this size, yet five deaths by suicide were recorded. This means that, after controlling for age and other factors, the rate of deaths by suicide in this study was approximately six times higher in people with CFS than in the general population.
According to one of the study authors, Dr Emmert Roberts from King's College London and South London and Maudsley NHS Foundation Trust, "This is the first study to demonstrate that there might be an increased risk of suicide in people diagnosed with chronic fatigue syndrome (CFS). Although the risk of a person with CFS dying by suicide is small, it is still greater than we see in the general population, and so patients, their families, and their physicians need to be aware of this."
Although the risk of death by suicide was higher for people with CFS compared to the general population, it was still substantially lower than for people with some psychiatric illnesses, including mood disorders such as depression.
The observational study did not investigate fully whether the increased risk of suicide in people with CFS was caused by their condition, leaving open the possibility that there are other factors at play which influence CFS patients' likelihood of dying by suicide.
"The next step is to see whether these findings can be replicated in a larger study," says Professor Matthew Hotopf, Director of the NIHR Maudsley Biomedical Research Centre (BRC), and another study author. "Although it's statistically very unlikely that our findings are due to chance, less than one percent of our study sample died by suicide. A larger study would be able to confirm our finding of elevated suicide risk in people with CFS, and could provide further information which could be used to identify which patients are most at risk. CFS can be a debilitating disorder, which impacts patients' lives substantially, so we need to ensure that patients are being offered the correct assessment and treatment."
More information: Emmert Roberts et al. Mortality of people with chronic fatigue syndrome: a retrospective cohort study in England and Wales from the South London and Maudsley NHS Foundation Trust Biomedical Research Centre (SLaM BRC) Clinical Record Interactive Search (CRIS) Register, The Lancet (2016). DOI: 10.1016/S0140-6736(15)01223-4