Quantifying work-related social inequalities in life expectancy: a methodological proof of concept

Employment and working conditions are strong social determinants of health, yet many epidemiologic studies fail to account for their impact on life expectancy calculations. Integration of working conditions into health estimates requires both valid methodology and data sources. Using the French national Health and Career Path Survey and French life tables, we quantified the impact of 4 major work-related factors (lack of job control, job insecurity, unemployment, and occupational physical activity) in explaining socio-occupational inequalities in life expectancy. Using a formula-based approach, we computed work-related loss in life expectancy according to socio-occupational group, separately by sex. Based on life expectancy at age 35 years, we estimated that 1.3-3.3 years of life lost for men and 0.5-1.8 years for women are attributable to a combination of these 4 key factors. Although subject to sources of under- and overestimation, the differential life expectancy at age 35 years between senior executives and manual workers would substantially decrease if these exposures were set at the theoretical minimum level. This proof-of-concept analysis demonstrates the utility of accounting for occupational factors and the potential to quantify improvements in life expectancy that would occur by modifying working and employment conditions.