Research suggests that, in individuals with carpal tunnel syndrome (CTS), low plasma pyridoxal 5'-phosphate (PLP) concentrations are related to an increased incidence and severity of symptoms associated with CTS. This study was designed to determine the relationship between plasma and red blood cell PLP concentrations and the severity and incidence of CTS symptoms. Thirty people with CTS were selected for a 9 month exercise study. Subjects were divided into either vitamin users or non-vitamin users based on supplement use data gathered at the beginning of the study. Blood was drawn at 1, 6 and 9 months. CTS symptoms questionnaires and health questionnaires were also administered at these intervals. The symptoms questionnaires were used to gather data on the frequency and nature of hand and wrist symptoms. Health questionnaires focused on vitamin supplement usage including frequency, amount and length of use. Mean plasma PLP, total plasma vitamin B6 and erythrocyte PLP concentrations were significantly higher in the sixteen vitamin users when compared to the fourteen non-vitamin users (p<0.001). While there was variation in plasma PLP and total plasma vitamin B6 over time, within each group, there were no significant changes in any of the status measures over the nine month period. Mean erythrocyte PLP concentration, in particular, was stable over time. In vitamin users, the intensity of pain, numbness and tingling was significantly higher when compared to non-vitamin users. In both groups, plasma PLP was negatively correlated with pain. This correlation reached statistical significance in vitamin users at month one and nine (p<0.01), but not at month six; a statistically significant correlation between these two variables was not found in non-vitamin users at any time point. Pain was also negatively and significantly correlated with plasma total vitamin B6 and erythrocyte PLP in vitamin users. No other symptoms were significantly correlated with the status measures. These results indicate that a higher vitamin B6 status may be related to a decrease in the severity of pain experienced by some individuals with CTS. / Graduation date: 1998

Graduation date: 1999