What Is Preclinical Multiple Sclerosis?
Because MRI is easily available, occasional patients who have imaging for, say, headaches have typical MRI findings of multiple sclerosis without recognized symptoms. This is termed “radiologically isolated syndrome.” At least 50% develop typical symptoms within several years and are then diagnosed with clinically definite MS. There is thus a preclinical phase, during which patients accumulate MRI lesions without symptoms. In fact, 90% of MRI lesions cause no symptoms because the brain can compensate by making new synapses (connections between neurons). This ability is termed brain reserve. With age, brain reserve may fail and patients may then develop “progressive” MS.
A new study supports the idea of preclinical MS by identifying an “MS Prodrome.” Approximately 14,000 MS cases and 67,000 controls in four Canadian provinces were included. Medical records for the five years before the first MS symptoms were reviewed. Compared to the controls, people with MS utilized more health resources, mainly for musculoskeletal, genitourinary, and psychiatric symptoms. They more commonly saw urologists and psychiatrists and higher proportions received prescriptions.
See: Lead author Wijnands.