Health related functional status in men with spinal cord injury: relationship with lesion level and endurance capacity

Study design: Cross-sectional study. Objectives: To determine the relationship of health related functional stat us with lesion level and endurance capacity in persons with spinal cord inj ury (SCI). Methods: Thirty-seven men with SCI were divided in four lesion groups: high tetraplegia (motor complete; C5 - C6, n = 10), low tetraplegia (motor comp lete, C6/7 - C8, n = 9). motor incomplete tetraplegia (n = 7), and parapleg ia (n = 11). Health related functional status was measured with the short v ersion of the Sickness Impact Profile (SIP68), including a physical (SOM), psychological (PSY) and social subscore (SOC). Endurance capacity, defined as maximal power output (POmax) and peak oxygen uptake (VO2peak), was measu red in a maximal exercise test on a wheelchair ergometer. Results: Total SIP68-score and SOM were significantly different between les ion groups, showing higher values in the high- and low-tetraplegia group. T here were no differences between lesion groups for PSY and SOC subscores. V O2peak and POmax were significantly higher in the paraplegia group, compare d to the high and low tetraplegia groups. VO2peak was also higher in the mo tor incomplete versus other tetraplegia groups. Significant Spearman correl ation coefficients were found for VO2peak and POmax with SIP68 and SOM (ran ging from -0.68 to -0.79) and SOC (ranging from -0.39 to -0.51). No signifi cant relationship was found with PSY. Hierarchical regression analysis show ed that after correction for lesion level, 22% of the variance of SIP68, 8% of the variance of SOM, and 30% of the variance of SOC was explained by PO max or VO2peak. Conclusions: Results indicate that there is an evident relationship between the physical dimensions of health related functional status and lesion lev el, but not for the psychological and social dimensions. After controlling for lesion level a significant amount of the variance of health related fun ctional status can be explained by endurance capacity parameters. Although no causal relationships can be established in this cross-sectional study, t hese results suggest that functional status may be improved by increasing t he endurance capacity.