Social participation as a mediator of the relationships of socioeconomic factors and longevity after traumatic spinal cord injury

Study design Cohort study. Objective Previous research has indicated that socioeconomic factors affect longevity after traumatic spinal cord injury (SCI). Our purpose was to evaluate whether social participation mediates the relationship between socioeconomic factors and survival status after SCI. Setting Medical university in the southeastern United States. Methods Participants ( N = 1540) met the following inclusion criteria: traumatic SCI of at least 1-year duration, minimum of 18 years of age, and having residual impairment from SCI. The main outcome measures were a) survival status as of December 31, 2019, identified by the National Death Index (NDI) search, b) socioeconomic status (SES), measured by education, employment status, and family income, and c) participation, measured by marital/relationship status, hours out of bed per day, days leaving home per week, and nights away home during the past year. Results Thirty nine percent of participants ( n = 602) were decreased by the end of 2019. Socioeconomic factors were associated with longevity controlling for demographic, injury characteristics, and health status. However, the association of SES with longevity was mediated by three social participation mobility indicators (hours out of bed, days out of house, and nights away from home), such that SES was no longer significantly related to longevity after inclusion of the participation variables. Conclusions Although socioeconomic factors are related to longevity, their relationship appears to be mediated by social participation mobility indicators. Intervention studies are needed to address the modifiable factors that may promote longevity, including promoting an active lifestyle.