Background Cardiovascular health shows significant socioeconomic inequalities, however there is limited understanding of how these inequalities are generated across the life course. Early adulthood (age 16–24y) is an important period for development of cardiovascular risk factors such as obesity and atherosclerosis, as well as for changes in behavioural risk factors. In this study we assess the contribution of early adulthood trajectories through education, employment or inactivity (age 16–24y) to cardiovascular health in mid-adulthood (age 46y).

Methods Participants are from BCS70 (n=7,061) with data on education participation and economic activity during early adulthood and cardiometabolic outcomes at age 46y. Longitudinal latent class analysis was used to identify groups following different socioeconomic trajectories across ages 16–24y, based on participation in education, employment within different occupational classes, unemployment or inactivity. Cardiometabolic outcomes (waist circumference, systolic blood pressure (SBP), log-HDL cholesterol, log-triglycerides, HbA1c) at age 46 were regressed on early adulthood socioeconomic trajectory class, with and without adjustment for adult socioeconomic position (SEP) (age 46). All models were adjusted for sex, childhood SEP, adolescent health and early adulthood partnership and parenthood.

Results Six classes of early adulthood socioeconomic trajectory were identified, and labelled according to the primary activity engaged in: (1) Continued education, (2) Managerial employment, (3) Skilled non-manual employment, (4) Skilled manual employment, (5) Partly skilled employment, (6) Inactive. There was an increasing trend in waist circumference and triglycerides across classes 1–6 at age 46. Compared to the ‘Continued education’ class, waist circumference showed an increase of 1.87 cm (95%CI 0.84,2.91) in class 2, to 3.94 cm (95%CI 2.35,5.52) in class 6, and triglycerides an increase of 9.69% (95%CI 3.26,16.53) in class 2 to 14.27% (95%CI 3.88,25.7) in class 6. Compared to the ‘Continued education’ class, SBP was higher in classes 2–5, e.g. an increase of 1.18 mmHg (95%CI 0.06,2.29) in class 2, and HDL cholesterol lower in classes 2–6, e.g. -3.51% (95%CI -5.71,-1.25) in class 2. No difference was seen in HbA1c levels across classes. Adjustment for occupational social class at age 46 resulted in only a small attenuation of these coefficients.

Conclusion Identification of socioeconomic trajectories allows assessment of socioeconomic exposures across the transitional period of early adulthood. These findings support the hypothesis that these exposures of early adulthood may contribute to development of behaviours or psycho-social factors which persist through adult life; further research is needed to understand these pathways, and the extent to which early adulthood socioeconomic trajectories are mediated by SEP in later life.