Socioeconomic disparities in prehospital factors and survival after out-of-hospital cardiac arrest.

OBJECTIVE: It remains unknown whether patient socioeconomic factors affect interventions and survival after out-of-hospital cardiac arrest (OHCA), and whether a socioeconomic effect on bystander interventions affects survival. Therefore, this study examined patient socioeconomic disparities in prehospital factors and survival. METHODS: From the Danish Cardiac Arrest Registry, patients with OHCA ≥30 years were identified, 2001-2014, and divided into quartiles of household income (highest, high, low, lowest). Associations between income and bystander cardiopulmonary resuscitation (CPR) and 30-day survival with bystander CPR as mediator were analysed by logistic regression and mediation analysis in private witnessed, public witnessed, private unwitnessed and public unwitnessed arrests, adjusted for confounders. RESULTS: We included 21 480 patients. Highest income patients were younger, had higher education and were less comorbid relative to lowest income patients. They had higher odds for bystander CPR with the biggest difference in private unwitnessed arrests (OR 1.74, 95% CI 1.47 to 2.05). For 30-day survival, the biggest differences were in public witnessed arrests with 26.0% (95% CI 22.4% to 29.7%) higher survival in highest income compared with lowest income patients. Had bystander CPR been the same for lowest income as for highest income patients, then survival would be 25.3% (95% CI 21.5% to 29.0%) higher in highest income compared with lowest income patients, resulting in elimination of 0.79% (95% CI 0.08% to 1.50%) of the income disparity in survival. Similar trends but smaller were observed in low and high-income patients, the other three subgroups and with education instead of income. From 2002 to 2014, increases were observed in both CPR and survival in all income groups. CONCLUSION: Overall, lower socioeconomic status was associated with poorer prehospital factors and survival after OHCA that was not explained by patient or cardiac arrest-related factors.

The Mediating Effect of Pupils' Physical Fitness on the Relationship Between Family Socioeconomic Status and Academic Achievement in a Danish School Cohort.

INTRODUCTION: Family socioeconomic status influences pupils' academic achievements, and studies have established positive associations between physical fitness and academic achievements. However, whether physical fitness mediates the relationship remains unknown. OBJECTIVE: We investigated if pupils' physical fitness mediates the pathway between family socioeconomic status and academic achievement using causal inference-based mediation analysis. METHODS: This study included 527 girls and 552 boys between 13 and 15 years of age from the Danish municipality of Aalborg. Physical fitness was measured through VO2max tests in 2010 and demographic data were obtained from nationwide registers. Family socioeconomic status was classified into four levels ranging from 1 to 4, where level 1 represents the lowest and level 4 the highest based on either family income or education. RESULTS: Controlling for sex, ethnicity, age, and parents' cohabitation status, all total effects display higher academic achievement with increased family socioeconomic status. Splitting the effects, the direct effects reveal the existence of other pathways not involving physical fitness. The indirect effects established physical fitness as a mediator showing that pupils from family socioeconomic status levels one, three, and four changes grade by - 0.13 [95% confidence interval (CI) - 0.26, - 0.01], 0.07 (95% CI 0.00, 0.14), and 0.24 (95% CI 0.14, 0.34), respectively, compared to socioeconomic status level two. The corresponding proportions mediated are 18% (95% CI 1, 57), 6% (95 CI 0, 13), and 12% (95% CI 7, 18) when family socioeconomic status is based on education. Classifying family socioeconomic status on income, pupils from family socioeconomic status levels one, three, and four show grade changes of - 0.07 (95% CI - 0.16, 0.02), 0.22 (95% CI 0.13, 0.32), and 0.26 (95% CI 0.15, 0.37), respectively, compared to socioeconomic status level two. The corresponding proportions mediated are 12% (95% CI - 6, 41), 30% (95% CI 16, 54), and 20% (95% CI 12, 32). CONCLUSION: In conclusion, pupils' physical fitness partially mediated the pathway between family socioeconomic status and academic achievement.

The effect of early-life and adult socioeconomic position on development of lifestyle-related diseases.

BACKGROUND: Early-life socioeconomic position (SEP) is associated with lifestyle-related diseases in adulthood. However, evidence is lacking on the extent to which adult SEP mediates this association. METHODS: Time to either chronic obstructive pulmonary disease (COPD), cardiovascular disease or diabetes were assessed in the Danish population born between 1961 and 1971 (n = 793 674) from age 30 until 2015. Early-life position was assessed in 1981 (by parental) and again at age 30 (own) by four markers; income, occupation, education-divided into high, middle, low-and a combined score for all markers. Using a counterfactual approach, we estimated the total effect of early-life position on disease onset and the degree to which adult position mediated this effect. RESULTS: Results of the time-to-event analysis showed a gradient of all early-life markers on the risk of developing all lifestyle-related diseases. Notably, comparing those in the lowest to the highest educational position, the hazard of COPD was 130% higher for women [hazard ratio = 2.30(95% confidence interval = 2.20-2.41)] and 114% higher for men [2.14 (2.05-2.25)]. About 67%(63-70%) of the effect of educational position was mediated through adult position for COPD, 55% for cardiovascular disease and 50% for diabetes. For the combined score 44, 29 and 33%, respectively, was mediated. CONCLUSION: About one-tenth to two-thirds of the effect of early-life position is mediated by the position attained in adulthood. The degree mediated depend on the outcome investigated, gender and the social position marker used indicating that alternative pathways may play a key role in developing effective policies targeting early-life behaviours.