Survival after spinal cord injury: a systematic review

Spinal cord injury (SCI) leading to neurological deficits produces long-term effects that persist over a lifetime. Survival analysis of patients with SCI, at individual and population level, is important for public health management and the assessment of treatment achievements. The current study evaluated survival following traumatic and non-traumatic SCI worldwide. A systematic review was conducted, and all included papers were assessed for quality using a purposely designed assessment form. Survival data were presented in Kaplan-Meier curves and compared using the log-rank test. Sixteen studies were included of which 11 concerned traumatic SCI, four non-traumatic SCI, and one both. Crude standard mortality rates (SMRs) revealed that overall mortality in SCI is up to three times higher than in the general population. Survival rates were statistically significantly lower in non-traumatic SCI than in traumatic SCI (log-rank p = 0.000). Age at injury, neurological level, extent of lesion, and year of injury have been described as predictors of survival. Causes of death stem from secondary complications, with failure of the respiratory system being the leading cause. This is the first systematic literature review on survival analysis following SCI worldwide. An increase in survival over time was found. However, the SMRs of individuals with SCI still exceed those of an age-matched non-disabled population, mainly due to secondary complications. Lower survival rates were observed in non-traumatic SCI compared with traumatic SCI.