Decline of the relative risk of death associated with low employment grade at older age

Abstract

Study objective - To explore whether the observed age related decline in the relative risk of death associated with low employment grade can be explained by the profiles of smoking, blood pressure and plasma cholesterol changing differently with age between the employment grades. Design - Prospective cohort study with 25 years of mortality follow up. Setting - Whitehall study. Participants - There were 16 984 men aged 40 to 69 years at baseline with complete information on smoking, blood pressure and plasma cholesterol. Main results - The relative risk of death associated with low employment grade decreased from 2.1 at 55-59 years of age to 1.3 at 85-89 years of age. Adjustment for smoking status and blood pressure, attenuated the age related decline of the relative risk by 18% and 3% respectively; adjustment for plasma cholesterol increased the decline by 3%. Taken together, these risk factors explain 20% of the observed age related decline. Conclusions - A small part of the observed age related decline in the relative risk of death associated with low employment grade can be explained by differential changes in the profiles of smoking, blood pressure and plasma cholesterol with age between the employment grades.