Decline of the relative risk of death associated with low employment gradeat older age: the impact of age related differences in smoking, blood pressure and plasma cholesterol

Study objective-To explore whether the observed age related decline in the relative risk of death associated with low employment grade can be explaine d by the profiles of smoking, blood pressure and plasma cholesterol changin g differently with age between the employment grades. Design-Prospective cohort study with 25 years of mortality follow up. Setting-Whitehall study Participants-There were 16984 men aged 40 to 69 years at baseline with comp lete information on smoking, blood pressure and plasma cholesterol. Main results-The relative risk of death associated with low employment grad e decreased from 2.1 at 55-59 years of age to 1.3 at 85-89 years of age. Ad justment for smoking status and blood pressure, attenuated the age related decline of the relative risk by 18% and 3% respectively; adjustment for pla sma cholesterol increased the decline by 3%. Taken together, these risk fac tors explain 20% of the observed age related decline. Conclusions-A small part of the observed age related decline in the relativ e risk of death associated with low employment grade can be explained by di fferential changes in the profiles of smoking, blood pressure and plasma ch olesterol with age between the employment grades.