STOCKHOLM – according to data presented at the annual congress of the European Committee for Treatment and Research in Multiple Sclerosis.
Of 49 patients who had been on DMT for at least 5 years and had shown no evidence of disease activity (NEDA) during that time, 26 continued to have NEDA through at least 5 years of follow-up, explained Tobias Monschein, MD, of the department of neurology at the Medical University of Vienna.
The cohort of patients had all been taking either interferon beta or glatiramer acetate after a first clinical episode leading to an initial diagnosis of MS. Patients all met Barkhof criteria for MS diagnosis on MRI, and all but six patients had oligoclonal bands found on examination of cerebrospinal fluid.
All patients in the cohort thus met criteria for clinically isolated syndrome (CIS) and MS under the 2017 revisions to the McDonald diagnostic criteria. “To our knowledge, this is the first study determining the risk of disease recurrence in a homogenous cohort of patients with CIS,” reported Dr. Monschein and collaborators.
Before stopping DMT, patients had to show at least 5 years of NEDA status; at that point, patients were offered the opportunity to discontinue medication. The decision to stop or continue taking a DMT was left to individual patient choice, Dr. Monschein said in an interview.
The cohort of patients who decided to discontinue DMT was seen yearly; they received a clinical examination that included expanded disability status scale (EDSS) rating. Patients also received an annual MRI.
Age at DMT discontinuation was predictive of remaining disease free, found Dr. Monschein and collaborators. The 26 patients who continued disease free after DMT discontinuation were a mean 29.7 years old, while patients who had disease recurrence were a mean 22.7 years old.
Looking at age as a dichotomous variable, the investigators found that the 16 patients who were 40 years or older when they stopped DMT had an 18.8% risk of MS recurrence, while the 33 patients younger than 40 years at the time of ceasing DMT had a 60.6% risk of recurrence.
Age, in fact, was the only patient, disease, or therapy characteristic that Dr. Monschein and colleagues found predictive of relapse: “Gender, type of DMT, treatment duration, and CIS symptom did not differ significantly between groups,” they reported.
The data “should not encourage patients to generally stop DMTs after a long NEDA period,” they noted.
In the context of shared patient decision-making, though, the data can inform discussion with patients who wish to discontinue DMTS after long disease-free periods, Dr. Monschein said.
“Physicians should encourage younger people to stay on DMTS despite long lasting NEDA status while in patients [older than] 40 years stopping DMTs together with regular clinical and radiological monitoring could be a reasonable option,” he and his colleagues advised.
Dr. Monschein reported no outside sources of funding and no conflicts of interest.
SOURCE: Monschein T et al. ECTRIMS 2019, .