The complex dynamics between sleep, pain, anxiety and depression

It seems almost obvious: if you are in pain, you cannot sleep. "Despite important insights, the classical medical framework with the so-called 'latent variable model' does not always lead to the best conceptualisation of (mental) disorders," says PhD student Zosia Goossens. "This is because it does not offer a comprehensive understanding of the complex interactions between symptoms," "The latent variable model posits that an underlying, 'latent' variable causes the observed symptoms. A bit like how the flu virus can cause fever, headache, coughing and muscle pain. Here, we take a different view: (mental) disorders can also arise from the interaction of different symptoms. This means that pain and insomnia can also be measured indirectly on the basis of the symptoms present."

"In our research, which utilised network analysis, we attempted to establish connections between various factors that determine sleep quality and pain experience through questionnaires. This provided us with a much broader view of which symptoms positively or negatively influence sleep and pain. Our analysis showed that it is not so much the pain itself that determines the quality of sleep, but that other factors such as anxiety and depression are much more strongly associated with our sleep than the experience of pain. It can therefore be said that pain has a slightly less direct influence on sleep than one might expect. At least, that is how our patients experience it."

"There are indications that patients who have had a good night's sleep feel less pain in the morning and that more severe pain only reappears around noon. Mental and physical fatigue can be a direct result of the pain experienced by the patient. Good sleep quality therefore has a pain-relieving effect. And that is crucial for the clinical treatment of pain."

"The research is far from over. We want to launch a large-scale pain and sleep study across Belgium and hope to include many more factors in the research. These could include financial problems, medication, support from the environment, and so on. However, this research is still awaiting approval from the Ethics Committee of the UVC Brugmann hospital."

In addition, the VUB will soon be installing a pain and sleep laboratory on the campus in Etterbeek. "We hope this will enable us to conduct efficient experimental research into the relationship between sleep and pain."

“Furthermore, experimental research will soon be launched in collaboration with KULeuven and UZ Leuven, in which we will systematically wake up both healthy people and people with chronic lower back pain for three nights in order to investigate the effect of interrupted sleep on pain sensitivity.”