“When a new neurological symptom develops in multiple sclerosis, one that isn’t related to an infection and lasts for more than 24 hours, it is considered to be an MS relapse,” explains Devon Conway, MD, a neurologist at the Mellen Center for Multiple Sclerosis at Cleveland Clinic in Ohio. Relapses are caused by inflammation in the central nervous system, and remissions occur as the inflammation dies down. But not every episode of symptom worsening in MS is a relapse. When old symptoms reappear but subside within 24 hours, the episode is referred to as a pseudorelapse or pseudoexacerbation, according to the Multiple Sclerosis Association of America. While the cause of a relapse or pseudoexacerbation may not always be easily identifiable, there are some common triggers of both, says Matthew McCoyd, MD, a neurologist and associate professor with the Loyola University Health System in Illinois. Here are some common triggers for MS symptom flares, as well as tips on how to avoid them. A meta-analysis published in Health Psychology Open evaluated how stress impacts MS and found some evidence that stress can be associated with relapses. The authors also found evidence that MS relapses and stress can have a bidirectional relationship. That means that stress may contribute to the development of a relapse and an MS relapse may also cause stress. Studies included in the analysis indicated that accumulated stress or the presence of many different stressful events increased the risk of relapse compared with a single stressful event. Likewise, chronic stress that lasted more than 48 hours has a greater effect on MS than acute stress. “Patients can dismiss stress, but it’s another condition, like high blood pressure or diabetes or obesity; it can impact all aspects of your health and it should be attended to,” Dr. Fox says. The National MS Society recommends a variety of strategies to help manage stress levels, including looking for ways to make your life less stressful, such as saying no to things you don’t have the time or energy to do, and asking for help when you need it. It also recommends regularly practicing a relaxation technique such as deep breathing, meditation, or yoga. Avoiding MS relapses isn’t the only good reason to reduce the stress in your life or learn to manage it better: Stress can also have a negative effect on your mental health. According to the National Institute of Mental Health, having a chronic disease like MS can make every aspect of life more stressful, and that can increase the risk of depression.
Lack of Sleep Can Worsen MS Symptoms
Getting enough restful sleep can be challenging when you have MS. Pain, restless legs, urinary or bowel symptoms, or temperature dysregulation are some of the top symptoms that can interfere with nightly z’s, according to the National MS Society. While no one likes being sleep deprived, it can be an even bigger issue for people with MS, says Dr. Conway. “Most people with MS have a lower reserve of energy,” and a lack of sleep can worsen MS symptoms, he says. A 2018 review of studies published in Current Neurology and Neuroscience Reports found significant associations between sleep disturbance and cognitive dysfunction in MS. Objective sleep measures (performed at a sleep lab rather than self-reporting) generally predicted objective impairments in processing speed and attention, according to the analysis. Other consequences of poor sleep can include increased pain, anxiety, fatigue, and problems with coordination, according to the National MS Society. In some cases, sleep difficulties for people with multiple sclerosis may be due to an underlying sleep disorder, such as obstructive sleep apnea, says Scott Ireland Otallah, MD, a neurologist who specializes in multiple sclerosis at Atrium Health at Wake Forest Baptist in Winston-Salem, North Carolina. People with MS are more likely to have insomnia, sleep-disordered breathing, narcolepsy, and REM sleep behavior disorder, according to the Sleep Foundation. If a sleep disorder is suspected, getting that diagnosed and treated may help reduce the likelihood of a relapse, says Dr. Otallah. Lifestyle modifications such as keeping a regular bedtime and awakening time, limiting alcohol consumption before bedtime, and drinking less fluid just before going to bed, may help improve sleep, the National MS Society suggests. But if you continue to have trouble sleeping, let your primary care doctor know so you can work together on improving your sleep.
Common Infections Can Cause Pseudoexacerbations and Lead to Relapses
Infections can cause an MS symptom flare, especially if that infection comes with a fever, says Otallah. “Urinary tract infections (UTIs) are common causes, because some people with MS have reduced bladder function,” says Conway. But any type of infection that weakens the immune system, like a cold or the flu, can cause a flare, he says. Technically, a true MS relapse is any new or acutely worsening neurological symptoms that are not related to an infection, fever, or other stresses and that last for more than 24 hours. That means that a worsening in MS symptoms experienced during a UTI or other infection may in fact be a pseudoexacerbation. However, infections are also associated with relapses. Some research suggests that relapse occurs in an estimated 30 percent of people with MS after an upper-respiratory infection, according to a review published in Frontiers in Immunology. To help prevent such infections and subsequent relapses, the National MS Society recommends that people with MS receive influenza and other vaccines according to standard vaccine guidelines. This guidance extends to the COVID-19 vaccine and booster.
Summer Heat Is a Common Cause of Pseudoexacerbations
Increased body heat is a common trigger for MS pseudoexacerbations. In fact, “in the old days, a hot-bath test was one of the ways doctors diagnosed MS,” notes Dr. McCoyd. The person with MS was immersed in hot water, and if their neurological symptoms appeared to worsen, it was considered evidence they had MS. Typically, heat causes the appearance or worsening of MS symptoms in areas that have been impacted by previous relapses, says Otallah. “So if a person has an area previously affected by demyelination — for example, say, a person had numbness on the left side for a couple of weeks two years ago — even though they’ve recovered from that attack, if they get overheated by being out on a hot day for a long time, their left side might start to feel numb,” he says. It doesn’t take much, Otallah adds: An elevation of just half a degree or more of body temperature can make those old MS symptoms come out. Temporary worsening of neurological function in MS caused by increased core temperature is commonly called Uhthoff’s phenomenon. Symptoms due to Uhthoff’s phenomenon go away following short periods of rest, removal of heat stressors, or use of active cooling methods, according to StatPearls. “Getting into air-conditioning, taking a cool shower, or wearing a vest filled with cooled water usually helps reduce heat symptoms,” says Otallah. RELATED: Cooling Products for Multiple Sclerosis
When to Treat MS Flares
Not all MS symptoms need to be treated. Tingling, fatigue, and mental fog generally go away on their own once the trigger is removed or an infection clears up. However, more severe MS symptoms that affect your ability to function normally, such as severe weakness, poor balance, or loss of vision, may indicate that you’re having a relapse, and your doctor may recommend treatment with steroids to shorten the duration and severity of the exacerbation, according to Johns Hopkins Medicine. And keep in mind that not all symptoms are caused by MS. If you’re experiencing symptoms that are concerning you for any reason, let your doctor know what’s going on. That way, you can figure out together what to do next.
