MADRID – Fatigue is one of the most frequent features of rheumatoid arthritis, and it needs to be assessed and addressed, several leading rheumatology experts urged at the European Congress of Rheumatology.
“Fatigue is an outcome of outstanding importance for patients with rheumatoid arthritis, and therefore it should be an outcome of outstanding importance for clinicians who take care of these patients,” said José António Pereira da Silva, MD, PhD, a professor of rheumatology at the University of Coimbra (Portugal) during a clinical science session dedicated to the topic.
“Fatigue is described as being significant by as many as 40%-80% of all patients with rheumatoid arthritis, and described as being severe by 41%-49% of these patients according to different studies,” Dr. da Silva said.
“The impact upon the quality of life from the patients’ perspective is quite varied but always rather important, if not ‘dramatic,’ ” Dr. da Silva said. Fatigue needs to be part of treatment targets alongside disease activity and thus regularly measured, he added.
The problem of fatigue
The problem, however, is that fatigue is such a complex construct, observed James Galloway, MBChB, PhD, of the Centre for Rheumatic Diseases at King’s College London. “It’s definitely multifactorial in origin; it’s a combination of inflammatory disease, psychosocial situations, and comorbidity.”
Moreover, said Dr. Galloway, “what people describe as fatigue is multidimensional; it’s not just how well you sleep, but how much energy you have, and it’s also how motivated you are.” The fatigue that accompanies RA is different from the fatigue that is experienced in daily life, he noted, and it has a huge impact on patients’ lives.
Determining the cause of fatigue can be challenging, said Wan-Fai Ng, MBChB, PhD, professor of rheumatology at the Institute of Cellular Medicine at Newcastle (England) University.
“Fatigue is a syndrome that often coexists with other symptoms, and there may be different type of fatigue,” Dr. Ng said. He noted that there were many potential underlying biological mechanisms, but the most studied so far is inflammation. Fatigue is probably driven, at least in part, by “sickness behavior” and there are frequent associations between fatigue and chronic inflammatory conditions such as RA and Sjögren’s syndrome.
“I think the role of conventional inflammatory mechanisms, at least in chronic fatigue in chronic conditions, remains unclear,” Dr. Ng added. “The biological systems, for example the vagus nerve, that regulate the immune system may play key roles in fatigue, especially in chronic inflammatory states.”
Whatever the underlying mechanism, it’s clear that there are multiple factors at play that need addressing if fatigue is to be properly addressed in the clinic. Dr. da Silva unveiled a new path analysis model that will be published in a future issue of Clinical and Experimental Rheumatology that showed how disease activity, pain, disability, sleep disturbance, and depression might all interlink to account for fatigue in patients with RA.