A new study from the USA, published in the journal Quality of Life Research, reports an investigation into sleep and pain problems in ME/CFS, finding that these symptoms are clearly related to the condition and that their severity can be measured using a standardised tool.
The vast majority of ME/CFS sufferers report some level of sleep disturbance and many report pain. These are defining symptoms of the disease, but a lack of standard measures means that findings on the type and severity of sleep problems in ME/CFS have been mixed.
ME Research UK has funded a number of studies over the years exploring sleep and pain in ME/CFS, including the dramatic impact these symptoms have on sufferers. We know that a poor night’s sleep and chronic pain can dramatically reduce quality of life and induce low mood.
A standardised tool for assessing these problems could greatly help clinicians and doctors when examining a patient with ME/CFS.
In this study, the researchers (from the University of Rhode Island, the American Institutes for Research, and the Centers for Disease Control and Prevention) aimed to validate the PROMIS tool in adults with ME/CFS.
PROMIS (Patient-Reported Outcome Measurement Information System) is a tool for assessing aspects of sleep disturbance and pain. It was developed to look at a number of conditions, including sleep disorder, rheumatoid arthritis and sickle cell disease. But how useful is it in ME/CFS?
The analysis was performed on patient data from a previous study conducted between 2012 and 2020 at seven ME/CFS specialty clinics across the USA. Baseline and follow-up data were available from patients with ME/CFS and from healthy control subjects.
The PROMIS tool is made up of four forms that ask questions about different aspects of sleep and pain, covering sleep disturbance, sleep-related impairment, pain interference and pain behaviour. Patients respond to each question using a simple scale of responses such as “always”, “often”, “sometimes”, “rarely” or “never”.
A total of 945 participants completed the initial assessment, including 602 patients with ME/CFS and 338 healthy control subjects, while 441 ME/CFS patients completed the follow-up assessment.
Baseline average scores of PROMIS sleep and pain measures ranged from 57.68 to 62.40, with the average score in the population being 50, indicating that ME/CFS patients clearly have problems with sleep and pain when compared with the general population.
These results support the validity of using PROMIS as a measurement tool for sleep and pain in ME/CFS.
Approximately 10% of participants reported “not at all/never” on all the pain interference questions, or reported “I had no pain” on all the pain behaviour items. While this indicates that a subgroup of ME/CFS patients either do not currently experience pain or never have, the overwhelming majority of ME/CFS sufferers do experience pain.
In fact, in general, ME/CFS participants had significantly worse scores compared with healthy controls on all four measures of sleep and pain. Interestingly, there was not a strong association between the function (or illness severity) of ME/CFS patients and their experience of sleep problems or pain, although further research is needed to investigate this in greater depth.
The PROMIS sleep and pain short forms are not specific to any one condition, and were developed to look at a range of diseases such as sleep disorder, rheumatoid arthritis and sickle cell disease. However, this study has found that the four PROMIS short forms are useful to assess sleep and pain outcomes in individuals with ME/CFS.
PROMIS could therefore be used by researchers and clinicians to examine individuals presenting with ME/CFS, and doctors could target appropriate support to those individuals requiring sleep and pain management, which would improve their overall quality of life.