Multiple sclerosis is typically characterized by relapses, i.e. neurological dysfunctions occurring within days, followed by more or less complete recovery. It was assumed that in the time between the relapses, the disease is dormant and no deterioration occurs. Only later in the course, usually after 10-20 years, does the progressive phase follow in most affected persons, with a more continuous increase in disability. However, systematic long-term studies and the use of increasingly effective drugs to prevent relapses have shown in recent years that continuous progression also occurs in patients with a typical relapsing course. This progression independent of relapse activity (PIRA) is responsible for the majority of the increase in disability from the earliest stages of MS. After the first descriptions of PIRA, numerous studies in different patient groups followed with the aim of better understanding this newly recognized phenomenon.
Until now, however, there was no uniform definition of PIRA, which made it difficult to compare and interpret the studies. Researchers from the Research Center for Clinical Neuroimmunology and Neuroscience (RC2NB) led by Jannis Müller, Cristina Granziera and Ludwig Kappos, who were already significantly involved in the initial description of PIRA, have now summarised the current state of knowledge about PIRA in a systematic review in the renowned journal JAMA Neurology and proposed uniform diagnostic criteria based on this review. Such uniform diagnostic criteria create better conditions for the early and reliable detection of PIRA and for the prevention of PIRA by means of targeted, individually tailored therapies.
View Abstract on JAMA Neurology.
16 October 2023
