Rather than taking medicine to ward off a future potential attack, patients diagnosed with multiple sclerosis (MS) may want to be a bit more conservative and wait with their doctors for the first few years to see how their disease progresses over time. That's the opinion of physicians at the Mayo Clinic who published research on that topic.¹

The study was published last August in the journal Annals of Neurology.

"Our study demonstrates that the longer the duration of MS and the lower the disability, the more likely a patient is to remain stable and not progress to a greater level of disability," said Sean Pittock, MD, a neurologist at the Mayo Clinic, and the study's lead investigator. "This isn't small issue; it's a big issue."

A Static Type of MS
This type of multiple sclerosis is known as benign MS. "The documentation of benign MS does exist, and this condition can be identified during an analysis of the patient at even 5 years with MS," added Moses Rodriguez, MD, a Mayo Clinic neurologist, and one of the study's investigators.

The researchers are proposing a definition of benign MS as patients who have the disease for a decade or more, but who also have less than a 10% likelihood of developing significant disability in the future.

Patients who have benign MS can have ongoing attacks, Rodriguez explained, but their disability does not progress from these attacks. "You have symptoms, but they go away, and if they come back, they go away again, typically after a week or so," Rodriguez said. "You might have a bad week or an attack—like the loss of vision in one eye—but you completely recover."

Most of the time, though, there are no outward signs of the disease in this case, he said.

Benign MS Equals Little Disease Progression
Pittock's team in their study found that only 7 percent of patients who had minimal or no disability after 10 years with MS progressed to greater disability, and none needed a wheelchair after 20 years with the disease. However, for those with moderate disability after 10 years with MS, their disease progressed to the point at which they needed assistance for certain functions 20 years after diagnosis.

"This confirms some other studies, but it flies in the face of the commonly held belief that MS is never benign and that ever person should be started on lifelong interferon therapy before we get a feel of how the natural course of their illness will behave," said Brian Weinshenker, MD, a neurologist at the Mayo Clinic who also took part in the study. 

Who Will Benefit From This Research?
Pittock and his colleagues say their findings will prove valuable to patients who have had benign MS for at least a decade, and for whom physicians can make a reasonable prediction that they will not develop progressive disability. But forecasting how a particular patient's MS will progress up to 5 years after diagnosis is particularly difficult, they stressed.

Another group of investigators set out to determine which patients are more likely to have benign MS.2 In the Northern Ireland study of 259 patients with the disease, the research team noted that benign MS occurred more often in women and those who were younger at MS onset.

Of 400,000 patients in the United States believed to have MS,³ Rodriguez estimates that about 70,000 of them have the benign form of the illness.

Of the Mayo Clinic research, Rodriguez stated: "This study raises questions about the current dogma out there that all patients should be started on medications as soon as possible. If we treat everyone early, we would treat some people who never needed treatment."

1. Pittock SJ, McClelland RL, Mayr WT et al. Clinical implications of benign multiple sclerosis: a 20-year population-based follow-up study. Ann Neurol 2004 Aug;56(2):303-6.
2. Hawkins SA, McDonnell GV. Benign multiple sclerosis? Clinical course, long term follow up, and assessment of prognostic factors. J Neurol Neurosurg Psychiatry 1999 Aug;67(2):148-52.
3. National Multiple Sclerosis Society. Who Gets MS? Available at: http://www.nationalmssociety.org/Who%20gets%20MS.asp. Accessed February 18, 2005.

John Martin is a long-time health journalist and an editor for Priority Healthcare. His credits include coverage of health news for the website of Fox Television's The Health Network, and articles for the New York Post and other consumer and trade publications.