C-reactive protein as an available biomarker determining mental component of health-related quality of life among individuals with spinal cord injury

Abstract

Objectives: C-reactive protein (CRP) has been shown to correlate with health-related quality of life (HRQL) in some chronic medical conditions. However, these associations have not yet described in spinal cord injury (SCI). In this study, we tried to identify biomarkers associated with HRQL in SCI.Design: Cross-sectional.Setting: Tertiary rehabilitation center.Participants: Referred patients to Brain and Spinal Cord Injury Research Center between November 2010 and April 2013.Outcome Measure: Blood samples were taken to measure circulatory CRP, leptin, adiponectin, ferritin, parathyroid hormone, calcitonin, thyroid hormones, fasting plasma glucose and lipid profile. All the analyses were performed with adjustment for injury-related confounders (level of injury, injury completeness and time since injury) and demographic characteristics. HRQL was measured with Short Form health survey (SF-36).Results: The initial inverse association between CRP and total score of SF-36 (P: 0.006, r = −0.28) was lost after adjustment for confounders. However, the negative correlation between CRP and Mental Component Summary (MCS) remained significant (P: 0.0005, r = −0.38). Leptin level was inversely correlated with Physical Component Summary (PCS) (P: 0.02, r = −0.30).Conclusion: Although CRP and leptin levels were not related with total scores of SF-36 questionnaire, CRP can be more useful in determining mental component of HRQL whereas leptin can be a determinant of physical component. The combined consideration of these two biomarkers may help to predict HRQL in individuals with SCI.