About 85 percent of people diagnosed with MS are initially diagnosed with the relapsing form of the condition, usually referred to as relapsing-remitting MS, which is characterized by periods of active symptoms — sometimes called flares or exacerbations — alternating with periods of less-severe symptoms. Eventually, as many as 90 percent of these people reach a stage known as secondary-progressive MS (SPMS), in which symptoms gradually worsen and a person experiences increasing levels of disability. That might include more difficulty walking, loss of stamina, and cognitive problems. Some people with SPMS continue to experience relapses, but many don’t. The transition from relapsing-remitting MS to secondary-progressive MS appears to be age dependent, with the forties being the most common period to experience it, according to a review article published in April 2021 in Frontiers in Neurology. However, the authors of the review say, because there is no consensus among experts regarding any specific diagnostic criteria for disability progression, nor are there any definitive biomarkers of progression, a diagnosis of SPMS can only be retrospective (after the fact). That limits doctors’ ability to treat MS progression in its early stages.
Age at Diagnosis and MS Progression
The thinking used to be that MS progressed more quickly in people diagnosed at an older age. Indeed, research published in the Journal of Neurology, Neurosurgery & Psychiatry found that children diagnosed with MS took longer to develop secondary-progressive disease (32 years) than adults diagnosed with MS (18 years), and they also took longer to reach disability milestones. But the study authors note that those diagnosed as children hit disability milestones at a younger age and therefore could be considered to have a poorer prognosis. Helen Tremlett, PhD, Canada research chair in neuroepidemiology and multiple sclerosis and a professor at the University of British Columbia in Vancouver, says that her work since 2006 has shown that late-onset MS does not necessarily mean “a worse outcome for the patient.” Dr. Tremlett participated in a study published in April 2015 in the European Journal of Neurology, which investigated whether the use of the widely prescribed MS drugs known as beta interferons delays the onset of secondary-progressive MS; it found that they do not. However, a study published in January 2019 in the Journal of the American Medical Association suggests otherwise. When researchers compared MS medications including beta interferons, glatiramer (Copaxone, Glatopa), fingolimod (Gilenya), natalizumab (Tysabri), and alemtuzumab (Campath, Lemtrada) versus no treatment at all, they found that treatment with any of these medications was associated with a lower risk of transition to SPMS. In particular, fingolimod, natalizumab, and alemtuzumab were associated with the lowest risk of progression to SPMS, and treatment was especially beneficial when started sooner — less than five years after disease onset — rather than later. Tremlett also coauthored a systematic review of MS research published in July 2017 in the journal Neurotoxicology that looked at risk factors associated with onset, relapses, and progression in MS. The review focused on factors that are modifiable, and among these, smoking appeared to accelerate disease progression. A more recent study, published in April 2020 in the journal Neurology, also identified smoking, along with older age, greater disability, motor and brain stem dysfunction, and spinal lesions at the time of diagnosis, as risk factors for transitioning from relapsing-remitting MS to secondary-progressive MS.
MS in Children
Up to 10 percent of MS cases are diagnosed in children and teens, according to the MS International Federation. Although MS in children is generally understood to be the same disease as MS in adults, there are some key differences. “Children experience similar MS symptoms to adults, including motor symptoms and weakness, but children tend to have more relapses than adults,” says Tanuja Chitnis, MD, a professor of neurology at Harvard Medical School and director of the Partners Pediatric Multiple Sclerosis Center at Massachusetts General Hospital for Children in Boston. A study published in June 2019 in Neurology further confirmed a higher relapse rate in children with MS than in adults and showed that children are more likely to be diagnosed with relapsing forms of the disease and often experience longer diagnostic delays than adults. Dr. Chitnis adds, “There is a slower course of progression, and kids have less disability early on in their disease course.” Still, she says, it’s important to note that a 30-year-old with pediatric-onset MS will have more disability than a 30-year-old with adult-onset MS. “Better treatment strategies are required in kids,” she says. There have been new initiatives to conduct clinical trials in children with MS to better understand effective treatment options in this age group.
MS After 50: Aging and MS Symptoms Overlap
Only a small percentage of people with MS receive their diagnosis after age 50. In some cases, these people have late-onset MS. But for some, the diagnosis represents a delayed identification of years — or even decades — of unrecognized symptoms. Mental and physical changes associated with aging can be similar to, or overlap with, symptoms of MS. Such symptoms may include muscle weakness, balance problems, fatigue, visual changes, cognitive impairment (such as problems thinking and remembering), and sleep disturbances. Older people with MS are also more prone to such MS complications as urinary tract infections, pneumonia, septicemia (infection of the blood), and cellulitis (bacterial skin infection) than peers who don’t have MS, according to the NMSS. In addition, age impacts your ability to recover from an MS relapse. A study published in October 2018 in the Multiple Sclerosis Journal showed that it’s more difficult to rebound from a relapse as you get older. The combination of aging and MS-related symptoms can exacerbate any of the health problems a person has. For instance, people with mobility problems due to MS may have difficulty traveling to and from healthcare appointments, so they may forgo these trips and miss needed care — for both their MS and other medical conditions. Decreased mobility can also be hard on the heart: Being less active is a known risk factor for heart disease. Research is mixed on the emotional effects of MS on older people. A study published in 2015 in the journal Psychology, Health & Medicine found evidence suggesting that older people with MS experience less psychological distress in response to impaired physical functioning than younger people with MS. But a study published in the Journal of Psychosomatic Research found that people age 65 and older who have MS were four times as likely to engage in suicidal thoughts as younger people with MS. At any age, depression and thoughts of suicide shouldn’t be ignored. If you or a friend or family member who has MS experiences signs of depression or is thinking about suicide, seek help from your doctor or a mental health professional.
Effect of MS on Life Span
Ultimately, MS is a chronic illness, not a terminal one. While it can slightly shorten life span, Chitnis says the reduction is unsubstantial: “I have seen many MS patients who live to be 70 or 80 years old.” A study published in July 2015 in the journal Neurology that used health data from Manitoba, Canada, confirms Chitnis’s observation. In the population studied, people with MS had a median life span of 75.9 years, while for people without MS, it was 83.4 years. According to the study, “The most common causes of death in the MS population were diseases of the nervous system and diseases of the circulatory system. Mortality rates due to infectious diseases and diseases of the respiratory system were higher in the MS population.” A study published online in July 2017 in the Journal of Neurology, Neurosurgery, and Psychiatry yielded similar findings. Among 1,388 Norwegians who developed MS between 1953 and 2012, the average life expectancy was found to be 74.7 years among people with MS compared with 81.8 years in the general population — but survival of MS increased over time, researchers noted. Additional reporting by Beth W. Orenstein and Christina Vogt.
