scale, a rating system that grades disability from
0 to 10. Unfortunately, it is not sensitive to subtle
changes and it places more emphasis on walking
than on other important factors such as bladder
dysfunction or cognitive problems. “We don’t have
very good measures of overall progression either,”
Dr. Chitnis said, referring to shrinkage of brain
tissue, called atrophy. “We need better measures to
tell us what the true rate of atrophy is in different
people and if or when it slows down.”
© NICOLENA NINA
“The Butterflies”
For Kristin Lewotsky, who was diagnosed with MS
in 2002 and PPMS in 2004, the most frustrating
part is, “the fact that it just never stops. If I could
just get my feet under me, I could adjust to it, but
it keeps going all the time,” said Lewotsky, who
lives in New Hampshire.
The puzzle of changes over time
People living with RRMS—which is defined by
typical relapses or exacerbations followed by full
or partial recovery—can face similar concerns. At
some point in time, their MS may become more
progressive in nature, with or without occasional
relapses. “We have this belief that if people with
RRMS live long enough, they’ll all reach SPMS,”
said Helen Tremlett, PhD, Canada Research Chair
in Neuroepidemiology and Multiple Sclerosis at
the University of British Columbia. “But we know
that some people never progress.”
An SPMS diagnosis is often made retrospectively,
Dr. Tremlett noted. For example, a neurologist
may look at a person’s subtly changing symptoms
over the course of a year without being able to
determine if they are signs of disease progression or simply deficits related to the most recent
relapse. The doctor will keep a close eye on other
changes related to physical or cognitive abilities,
but come to the conclusion that it is SPMS only
after several years.
Statistics from studies—gathered largely before
there were any disease-modifying therapies—
indicate that nearly 10% of people with RRMS will be
considered secondary-progressive after five years;
25% after 10 years; 50% after 20 years. Clearly,
even in the past, some people never progress,
confirming Dr. Tremlett’s observation. But some
people who faithfully take a disease-modifier for
years do begin to progress in time. Whether this
would have happened sooner without their drug
therapy remains hard to pin down.
Why? Why do some people progress and others
don’t? Why does the disease differ so much from
one person to the next? “The answers will teach us
about what’s driving this progression,” Dr. Rudick
said. Researchers are hot on the trail of indicators,
predictors and risk factors associated with progressive MS.
MRI plus and minus
For diagnosing, MRI continues to be one of the
most important tools. However, it is impossible
to determine what type of MS a person has from
an MRI scan alone. “The imaging is very nonspecific,” said Jugnu Jain, PhD, MS disease area
expert at Vertex Pharmaceuticals, at the think tank
