The Effect of Socioeconomic Deprivation on the Association between an Extended Lifestyle Score and Health Outcomes in the UK Biobank Cohort

Background - Combinations of unhealthy lifestyle factors can interact synergistically to increase associated mortality. While combinations of 'traditional' risk factors such as smoking and alcohol consumption are well described, the mortality associated with combinations that incorporate a wider range of 'emerging' lifestyle factors' (e.g. television viewing time) is not. The influence of socioeconomic deprivation on wider lifestyle risks also remains unclear. We aimed to examine whether deprivation modifies the association between an 'extended' lifestyle score and adverse health outcomes. Methods - Analyses performed using 328,594 adult participants' data from UK Biobank. Cox-proportional hazard models were used to examine how the association between an extended lifestyle score (incorporating sleep, TV viewing, smoking, alcohol, diet and physical activity) and health outcomes (all-cause mortality and cardiovascular disease (CVD) mortality and incidence) is modified by deprivation. Findings - There was a significant interaction (p<0.0001) between lifestyle score and deprivation for all-cause and CVD mortality. Hazard ratios (HR) for these outcomes were highest for those in the less healthy lifestyle category and most deprived quintile. In the least deprived quintile, the HR for all-cause and CVD mortality in individuals from the less healthy lifestyle category, compared with the more healthy category, was 1·65 (95% CI: 1·25-2·19) and 1·93 (1·16-3·20), respectively. Whereas in the most deprived quintile those from the less healthy category had a HR of 2·47 (2·04-3·00) for all-cause mortality and 3·36 (2·36-4·76) for CVD mortality. Interpretation - Wide combinations of lifestyle factors are associated with disproportionate harm in deprived populations. Public health and individual level interventions that address a wider range of unhealthy lifestyle factors in areas of deprivation may reduce inequalities. Funding - Research presented here used UK Biobank data and was designed, conducted, analysed and interpreted entirely independently of any funding sources. Conflicts of Interest - The authors declare that they have no competing interests. Ethics committee approval - All participants provided written informed consent to participate in the UK Biobank study agreeing to data collection, analysis and record linkage. The UK Biobank study was approved by the North West Multi-Centre Research Ethics Committee. This study is part of UK Biobank project 7155 (NHS National Research Ethics Service (16/NW/0274)).