Can work-related exposures during life explain the increasing social gradient in cardiovascular disease?

Research problem and specific questionsDespite the overall decrease in cardiovascular (CV) mortality there is, especially among women, an increasing social gradient in Sweden. The explanation is not known. Our aim is to analyse to what extent this gradient can be explained by the increasingly unsecure labour market.

The research questions are: How large a proportion of the effect of education on CV health is mediated through weak labour market attachment (LMA, unemployment and precarious employment)?

What are the other possible work-related mechanisms?Data and methodFour life-course cohorts, born 1965 and 1973, will be used. Two of them are based on extensive register data about all Swedish inhabitants.

Two are based on repeated questionnaires and extensive register data on all school-leavers from grade 9, in a middle-sized town. One contains repeated clinical data for 40-years. Data on exposure to LMA are available from school to midlife. Incident CV diagnoses and metabolic risks will be measured around age 56 and 51.

All cohorts will be controlled for reverse causation and other confounders.While the register cohorts are complete and provide power and national representativity, the school cohorts provide rich data of high validity for analysing mechanisms and clinical outcomes.

A qualitative study about possible mechanisms will be performed among those with highest risk of weak LMA who have been followed during 40-years with interviews.Sociatal relevance and utilisationElimination of avoidable health inequalities is a major goal in the Swedish public health policy. To reach the goal, knowledge is needed about the mechanisms behind.

The increasingly insecure labour market is our focus, a priority also in policies around EU.

Our results can be used in health promotion and by work environmental actors to support targeted interventions aiming at improved equality in health and sustainable work conditions during life.Plan for project realisationRegister update will be made of one school cohort.

Advanced mediation analyses of work conditions will be made for the educational gradient in CV health, using latest methods for selecting confounders.

Several mediators can be included at the same time, so the effect of structural factors on health behaviour can be analysed. Follow-up interviews will be performed with the early unemployed group. The theoretical development aim at developing a working life-course theory. The budget cover salaries and register updates.