In many cases, multiple sclerosis starts long before the diagnosis
Years before they are diagnosed, persons with multiple sclerosis (MS) make significantly more visits to doctors and hospitals than others. Specialists have recently discussed whether this might represent a preliminary phase of MS – known as a prodrome. A research team at the Technical University of Munich (TUM) has now published results of a study suggesting that, in many cases, the complaints may relate to unrecognized early clinical MS events.
Persons suffering from the autoimmune disease multiple sclerosis can develop various neurological symptoms caused by damage to the nervous system. Especially in early stages, these may include sensory dysfunction such as numbness or visual disturbances. In most patients, MS starts with recurring episodes of neurological disability, called relapses or demyelinating events. These clinical events are followed by a partial or complete remission. Especially in the beginning, the symptoms vary widely, so that it is often difficult even for experienced doctors to interpret them correctly to arrive at a diagnosis of MS.
Above-average numbers of medical appointments
It has been evident for some time, however, that patients with MS show significantly higher numbers of physician visits and hospital admissions even years before the first diagnosis as compared to healthy control persons. In recent years, specialists have seen this pre-diagnosis period as a possible prodromal phase of the disease.
MS often begins far in advance of the diagnosis
A new study carried out by a team working with the neurologist Prof. Bernhard Hemmer at TUM suggests that many complaints prior to diagnosis might not represent a prodromal phase. “Instead, we suspect that unrecognized MS relapses cause these individuals to seek medical attention,” says Prof. Hemmer. “That is because we have found that the physician appointments and hospital admissions frequently involved complaints indicating typical MS symptoms. We believe that many complaints that have been attributed to a prodromal phase are in fact caused by ongoing disease. We therefore believe that, although the disease has not yet been diagnosed, it is fully active and not in a preliminary or prodromal phase.”
A path to an earlier diagnosis
The results of the study could also open up possibilities to optimize MS treatment: “The sooner MS is recognized, the better we can treat the disease,” says first author Dr. Christiane Gasperi, a physician and researcher at the Neuro-Head Center at the TUM Klinikum rechts der Isar. “We now need to take a closer look at which early symptoms of MS might be overlooked. This could allow us to recognize the disease at an earlier stage and thus enable earlier treatment initiation.”
Less frequent respiratory tract infections
Along with the more frequent complaints in the years before an MS diagnosis, the results of the study also showed that persons with MS were actually less likely to seek medical attention for upper respiratory tract infections. “This was unexpected, in view of the fact that MS relapses have sometimes been associated with infections,” says co-first author and Adjunct Teaching Professor Dr. Alexander Hapfelmeier of the TUM Institute of General Practice and Health Services Research. “However, future studies will be needed to determine whether there is a causal link between MS and a degree of protection against certain infections, or whether the health data we analyzed reflect protective behavior adopted by persons with MS.”
The study by Prof. Bernhard Hemmer, Dr. Christiane Gasperi and Dr. Alexander Hapfelmeier was conducted in cooperation with the Bavarian association of registered physicians (KVB), which provided the ambulatory claims data of several thousand persons in Bavaria. The study was funded by:
The consortium Data Integration for Future Medicine (DIFUTURE, BMBF 01ZZ1804[A-I]), which is funded by the Federal Ministry of Education and Research (BMBF) under the Medical Informatics Initiative of the German federal government.
The MultipleMS project of the Horizon 2020 research and innovation program of the European Union (EU RIA 733161).
The TUM Cluster of Excellence SyNergy (EXC 2145 SyNergy – ID 390857198), funded by the Federal Ministry of Education and Research (BMBF) and the Free State of Bavaria under the Excellence Strategy of the Federal Government and the Länder.
Prof. Dr. Bernhard Hemmer
Klinikum rechts der Isar of the
Technical University of Munich (TUM)
Clinic and Polyclinic for Neurology
phone: +49 89 4140 4601
Systematic Assessment of Medical Diagnoses Preceding the First Diagnosis of Multiple Sclerosis
Christiane Gasperi, Alexander Hapfelmeier, Tanja Daltrozzo, Antonius Schneider, Ewan Donnachie, Bernhard Hemmer
Neurology, 15 June 2021, 96 (24) e2977-e2988