Currently, there is no known cause for multiple sclerosis (MS). While many doctors consider MS to be an autoimmune disease, nobody knows what prompts this immune response. A combination of environmental and genetic factors is thought to play a role. However, a new study suggests that the use of anti-tumor necrosis factor alpha (TNFα) inhibitors could increase the risk of developing multiple sclerosis, particularly in those who already have rheumatic disease.

Evaluating the Research

According to an article from Eve Bender in MedScape, researchers sought to understand whether the use of TNFα inhibitors in those with either rheumatic disease or inflammatory bowel disease (IBD) increased the risk of MS, compared to those with the same conditions who did not use TNFα inhibitors. To begin, researchers sourced data from population-based healthcare-linked databases from four Canadian provinces. They specifically used data from individuals with rheumatic disease or IBD over an 18-year period. TNFα inhibitors administered used by patients included certolizumab, adalimumab, infliximab, golimumab, and etanercept. After sourcing the data, the researchers then evaluated cases of multiple sclerosis.

The study, published in Neurology, found that:

• 462 out of 300,000 patients (0.154%) with rheumatic disease developed MS during the follow-up period. Of these patients, 18 (3.89%) had used TNFα inhibitors. However, after adjusting for other variables, the researchers found that TNFα inhibitor use increased MS risk by 105% within this patient population.
• Patients who developed MS usually began TNFα inhibitor use approximately two years prior to the condition’s manifestation. However, doctors state that MS prodrome could occur up to five years earlier than manifestation.
• While there seemed to be a slightly increased risk of developing MS after TNFα inhibitor use in patients with IBD, the findings were not statistically significant.

Ultimately, the researchers found a correlation between TNFα inhibitor use and increased MS risk in those with rheumatic disease. However, there is no data that suggests that TNFα inhibitors are causative of MS. The study authors do recommend, though, that TNFα inhibitors should not be used for patients with rheumatic disease who have any family history of multiple sclerosis. Please speak with your doctor or care team before making any medical decisions.

What is Multiple Sclerosis (MS)?

Multiple sclerosis is a chronic neurological and central nervous system (CNS) disease in which the immune system attacks and destroys the myelin sheath. Normally, the myelin sheath protects nerve cells. When the myelin sheath is damaged, nerve cells may also become damaged, inhibiting communication between the brain and the body. MS may be considered progressive (without remission) or relapsing and remitting (with periods of symptoms and periods of remission). Women are 2x more likely than men to develop MS. Additional risk factors include being between 20 and 40 years old, having a family history of MS, being Caucasian, living in a temperate climate, smoking, or having other autoimmune diseases. Symptoms can (but do not always) include:

• Numbness or weakness in one or more limbs that often occurs unilaterally
• Problems with balance and coordination
• Slurred speech
• Lhermitte sign (electric shock sensations that occur with certain neck movements)
• Tremor
• Unsteady gait
• Double, blurred, or impaired vision
• Fatigue
• Dizziness
• Problems with sexual, bladder, or bowel function