Life-expectancy estimations and the determinants of survival after 15 years of follow-up for 81 249 workers with permanent occupational disabilities

Abstract

Objectives: This study attempts to estimate life expectancy and explore the determinants of survival for workers with permanent occupational disabilities.

Methods: A database on permanent occupational disabilities occurring between 1986 and 2000 was linked with the national death registry database to construct the survival function. A method with Monte Carlo simulation was used to extrapolate survival for up to 600 months to derive the life expectancy for different disability grades (N=81249). A Cox (proportional hazard) regression was carried out to explore the determinants and to estimate the hazard ratios. Demographic variables, including age, gender, insured wage, severity of disability, injury causes, and organ-system disability, were included in the model as covariates.

Results: The results indicate that the survival period for workers suffering permanent occupational disabilities is shorter than that of the general population, amounting to an estimated loss of life expectancy ranging from 5 to 19 years. After adjustment for age and gender, a higher severity of disability, impairment of vital organs or lower extremities, and a lower insured wage had a significant association with shorter survival. Injury types, including transportation incidents, being struck by sliding objects, or a trip, slip or stumble, and collapse injury, indicated hazard ratios of between 1.24 and 1.34, as compared with injuries such as being trapped or caught in machinery.

Conclusions: The findings identify major determinants for predicting survival for workers with permanent occupational disabilities; these determinants may be of use in improving the equity of the compensation system for workers.