Survival Analysis in Patients with Chronic Traumatic Spinal Cord Injury

Iran J Public Health. 2019 Dec;48(12):2260-2269.

Abstract

Background: The goal of this study was to determine hazard rate of death rate and the causes of death in Iranian patients with Traumatic spinal cord injury (TSCI).

Methods: Overall, 1024 patients with chronic traumatic spinal cord injury referred to Brain and Spinal Injury Research Center, Tehran University of Medical Sciences, Tehran, Iran from Jan 2013-2017 were enrolled. Epidemiological and neurological data, along with secondary complications were recorded for all participants. In the case of death, the cause, and the date of death were recorded. The Kaplan-Meier method was used for survival analysis. A log-rank test was carried out to compare survival due to different risk factors. Risk factors and relative risk estimates associated with death were assessed by means of a Cox regression model.

Results: Nineteen percent were lost to follow up. During the follow-up period, 22 out of 830 remaining cases (2.6%) died. Deaths were only observed in patients with cervical injuries (59% in C1-C4 level and 41% in C5-C7 level). Kaplan-Meier Log-rank test showed that probability of survival was significantly less in females, complete injury cases, patients with cervical spine injury, depression, and ADR (Autonomic dysreflexia). Controlling for age, sex and education level, Cox regression model showed that hazard rate of death was significantly affected by the categorical variables such as level of injury (HR=0.2, 95% CI=0.12-0.39), severe ADR.

Conclusion: Probability of survival is lower in female individuals, cases with complete injuries, patients with cervical spine injury, individuals with depression (BDI>10), and clients who experience ADR.

Keywords: Iran; Mortality; Survival; Traumatic spinal cord injury.