Correlation Between Rnfl and T25FW over a 2-Year Period in a Cohort of MS Individuals
Objectives: : Identify if RNFL measurement by OCT correlates with timed 25 foot walk (T25FW) and serves as a surrogate anatomical marker of functional decline in individuals with MS.
Methods: This was a longitudinal study of 51 MS patients. Each subject had OCT and T25FW measured at two time-points, separated by 1-2 years.
Results: There was no significant correlation between T25FW and RNFL (r=0.01, p> 0.05). There was a trend to a decrease in the RNFL over time, but not at the level of statistical significance. A paired sample t-test was done to examine any differences for T25FW and for RNFL thickness at year one versus year two. No significant changes were seen for T25FW (p=.212, p>0.05) or for changes in RNFL (p=.104, p>0.05) in that time period. The T25FW data was further trichotomized (< 6 seconds; 6-7.99 seconds, and ≥ 8 seconds). None of the measurements for the subgroups had significant differences from one year to the next.
Conclusions: This pilot study examined the relationship between RNFL and T25FW over a follow up of two years. No relationship was found between the two parameters for the group as a whole or for timed performance subgroups. Future studies with larger cohorts and duration are warranted.