Women With MS Less Likely to Receive Treatment Than Men

— Is "therapeutic inertia" to blame?

MedicalToday

Women were less likely than men to be treated for relapsing multiple sclerosis (MS), French registry data showed.

Women had a lower probability of receiving any disease-modifying treatment (DMT) and were even less likely to get high-efficacy DMTs, reported Antoine Gavoille, MD, of Hospices Civils de Lyon in France, at the European Committee for Treatment and Research in Multiple Sclerosis (ECTRIMS) annual meeting in Copenhagen.

The study included 22,657 relapsing MS patients with disease onset at an average age of 30. Most (74.2%) were women.

Over a median follow-up of 11.6 years, women were significantly less likely to be treated with any DMT (OR 0.92, 95% CI 0.87-0.97) or with a high-efficacy DMT (OR 0.80, 95% CI 0.74-0.86), Gavoille said.

The findings suggest "therapeutic inertia" in women, noted co-author Sandra Vukusic, MD, PhD, also of Hospices Civils de Lyon.

"The main impact of this inertia is the less effective control of disease activity during DMT-free periods, leading to the accumulation of lesions and an increased risk of long-term disability," she said. "This represents a real loss of opportunity for women, especially in an era where DMTs are so effective when used early."

Treatment decisions can be influenced by a desire to become pregnant well before pregnancy occurs -- even if it doesn't occur, Gavoille noted. Because of this, women in childbearing years might be under-exposed to DMTs or to high-efficacy DMTs compared with men.

"Neurologists might be hesitant to prescribe DMTs, particularly if they are not comfortable with managing pregnancy-related issues," Vukusic pointed out.

Women don't want to take risks that may harm their child or pregnancy and may have concerns about congenital malformations, fetal loss, or fetal growth disorders, she added. "Women will also experience discomfort if their neurologist seems uncertain," she said.

The researchers evaluated data from the French MS registry (), including all MS patients with a relapsing onset from ages 18 through 40 who were followed from 1997 through 2022.

The primary outcome was the yearly probability of receiving any DMT -- adjusted for disease severity (relapses, disability scores, and MS phenotype) and pregnancy/post-partum periods -- to identify treatment differences in men and women not tied directly to pregnancy.

Differences in treatment varied among DMTs and years:

  • Teriflunomide (OR 0.87), S1PR-modulators (OR 0.78), and anti-CD20 drugs (OR.80) were significantly underused by women throughout the time they were available
  • Interferon beta (OR 0.99) and natalizumab (OR 0.96) were less used initially by women, then used equally between men and women after some time
  • Glatiramer acetate (OR 1.27) and fumarate (OR 1.17) were used equally at first, then more frequently in women

Overall, differences in use appeared after 5 years of disease duration for DMTs and after 3 years for high-efficacy DMTs, and didn't vary significantly by patient age.

A subanalysis of 5,268 patients showed that women were undertreated outside of pregnancy and post-partum periods, with further declines starting about 9 months before conception. This indicates that pregnancy may account for some of the treatment gap between men and women, but doesn't explain everything, Gavoille said.

The findings indicate a need to reassess how treatment decisions are made for younger women with MS, Vukusic noted. "Women may not be receiving the most effective therapies at the optimal time, often due to concerns about pregnancy risks that may never materialize," she observed.

"The use of DMTs and high-efficacy DMTs is frequently limited by potential and unknown risks associated with pregnancy, as there is often insufficient data available when these drugs first come to market," she added.

  • Judy George covers neurology and neuroscience news for , writing about brain aging, Alzheimer’s, dementia, MS, rare diseases, epilepsy, autism, headache, stroke, Parkinson’s, ALS, concussion, CTE, sleep, pain, and more.

Disclosures

Gavoille reported no disclosures.

Vukusic reported relationships with from Biogen, BMS-Celgene, Janssen, Merck, Novartis, Roche, Sandoz, and Sanofi-Genzyme.

Primary Source

European Committee for Treatment and Research in Multiple Sclerosis

Gavoille A, et al "Is there therapeutic inertia in women with MS?" ECTRIMS 2024, Abstract 1316/O089.