July 13, 2009

Several studies have suggested that keeping fit physically and mentally can help people with MS preserve their level of functioning in addition to providing other health and life benefits. Two recently published studies have examined this topic from different perspectives, adding to the evidence at hand.

In the first study, 21 MS subjects and 15 controls were assessed for aerobic fitness, given cognitive tests, and scanned using MRI techniques that measure brain structure volume and neuronal tract integrity. Analysis of the MRIs revealed that several of the gray matter structures evaluated were smaller in the MS subjects vs. controls, indicating MS-related atrophy in these regions as had been shown in previous studies. In addition, the integrity of certain white matter tracts was reduced in the MS subjects. However, these negative effects were reduced in subjects with greater aerobic fitness.

In the other study, a team of researchers evaluated information processing speed and used MRI to measure brain atrophy in 38 people with MS. In addition, they assessed the subjects' vocabulary as a measure of intellectual development over the subjects' lifetimes. As expected, they found that cognitive processing was negatively correlated with brain atrophy. However, brain atrophy had less of an effect on cognitive processing in subjects with larger vocabularies. The authors speculate that prior intellectual enrichment provides a degree of "cognitive reserve" that preserves brain function despite tissue damage.

There are a few caveats to note about these studies. The results from the first study can be interpreted in two different ways -- (1) physical fitness helps preserve brain function and structure, or (2) people whose brain tissue damage is less affected by MS have less depression, fewer physical impairments, etc., and thus are better able to stay physically active. In the second study, it's unclear whether someone already diagnosed with MS could try intellectual enhancement strategies (by taking classes, for instance) to build up their cognitive reserve and perhaps stave off cognitive decline. Clinical trials of physical fitness and intellectual development regimens would help answer these questions. In the meantime, if you have MS and are inclined to get in better shape and/or take up learning something new, doing so may also help preserve brain tissue and cognitive functioning.