Childhood socioeconomic position and cardiometabolic risk in young adulthood- the impact of mental health.

BACKGROUND: Low socioeconomic position in childhood is associated with greater cardiometabolic disease risk later in life. The aim of the current study is to examine the mediating impact of mental health on the association between childhood socioeconomic position and cardiometabolic disease risk in young adulthood. METHODS: We used a combination of national registers, longitudinal questionnaire-data and clinical measurements from a sub-sample (N = 259) of a Danish youth cohort. Childhood socioeconomic position was indicated by the educational level of the mother and the father at age 14. Mental health was measured by four different symptom scales at four age-points (age 15, 18, 21 and 28), and combined into one global score. Cardiometabolic disease risk was measured by nine biomarkers at age 28-30 and combined into one global score by sample-specific z-scores. We conducted analyses within the causal inference framework and evaluated the associations using nested counterfactuals. RESULTS: We found an inverse association between childhood socioeconomic position and cardiometabolic disease risk in young adulthood. The proportion of the association which was mediated by mental health was 10 (95% CI: -4; 24) % and 12 (95% CI: -4; 28) % using educational level of the mother and the father as indicator, respectively. CONCLUSIONS: Accumulated poorer mental health in childhood, youth and early adulthood partially explained the association between low childhood socioeconomic position and increased cardiometabolic disease risk in young adulthood. The results of the causal inference analyses rely on the underlying assumptions and correct depiction of the DAG. Since these are not all testable, we cannot exclude violations that potentially could bias the estimates. If the findings can be replicated, this would support a causal relationship and direct potentials for intervention. However, the findings point to a potential for intervention in young age in order to impede the translation of childhood social stratification into later cardiometabolic disease risk disparities.

Evaluating the association between socioeconomic position and cardiometabolic risk markers in young adulthood by different life course models.

BACKGROUND: Cardiometabolic health in adulthood is associated with socioeconomic position (SEP) in childhood. Although this has been studied by previous research several questions need to be addressed. E.g. knowledge about the association with timing, extent of the exposure as well as lifestyle and adult SEP, is essential to address the increasing social gradient in cardiometabolic diseases. METHODS: This study included a sub-sample (N = 264, 50% women, age 28-30) from an ongoing cohort study. We used a combination of national registers, longitudinal questionnaire data and clinical data. We examined the association between childhood SEP and cardiometabolic risk, measured by a score of multiple risk markers in young adulthood. SEP-indicators included mother's educational level and household income. The association was evaluated by four different life course models; the latent effects model, the pathway model, the cumulative model and the social mobility model. RESULTS: We found an inverse association between mother's educational level and cardiometabolic risk. The association was statistically significant evaluated by the pathway and cumulative life course models, however statistically insignificant evaluated by the latent effects model. No specific association with social mobility was observed. However, high adult educational level seems to have a protecting impact on the association. No association was found between household income and cardiometabolic risk in any of the applied life course models. CONCLUSION: Low childhood SEP, represented by mother's educational level but not household income, is associated with increased cardiometabolic risk in young adulthood. The accumulation of exposure, lifestyle and adult educational attainment are important for the association. In contrast, intergenerational social mobility does not seem to have a specific impact on the association and we find no evidence for a particular timing in childhood.

Subjective social status and cardiometabolic risk markers in young adults.

BACKGROUND: Low subjective social status (SSS), the perceived status in the social hierarchy, is associated with cardiometabolic risk in middle-aged and older adults. However, most studies are cross-sectional and very little is known about the association in adolescence and young adulthood. The aims of this study were; a) to prospectively investigate the association between SSS at ages 15 and 28 and cardiometabolic risk at age 28-30 and b) to examine if such an association was independent of smoking, physical activity and objective measures of social position. METHODS: The study used questionnaire information at ages 15 and 28 from the West Jutland Cohort Study (N = 3681), health measurements from a sub-sample of the cohort (N = 264, age 28-30, 50% women) and information from population-based national registers. The independent variable was a measure of SSS evaluated by a 10-rung ladder scale and dichotomized at the 25th percentile of data from the cohort study population. The outcome measure was a composite score of cardiometabolic risk including measures of lipids, inflammation, blood pressure and glucose-metabolism. Co-variates included smoking, physical activity, childhood and adulthood socioeconomic position. Sex-stratified linear regression analyses were performed to evaluate the associations between SSS and cardiometabolic risk. RESULTS: In both sexes, low SSS at age 28, but not at age 15, was significantly associated with increased cardiometabolic risk at age 28-30. Neither smoking, physical activity, childhood or adulthood objective socioeconomic position fully explained the associations. CONCLUSION: In young adulthood, SSS was inversely related to cardiometabolic risk after accounting for smoking, physical activity and objective measures of socioeconomic position. These findings suggest that SSS could play a role in the social disparities in cardiometabolic risk in addition to traditional measures of socioeconomic position.

Traditional and novel cardiometabolic risk markers across strata of body mass index in young adults.

BACKGROUND: Cardiometabolic risk increases with increasing body mass index (BMI). The exact mechanism is poorly understood, and traditional risk assessment of young adults with obesity has shown to be ineffective. Greater knowledge about potential new effective biomarkers and the use of advanced cardiac imaging for risk assessment in young adults is, therefore, necessary. OBJECTIVE: This study aims to explore traditional and novel cardiometabolic risk markers across strata of BMI in young adults. METHODS: Participants (N = 264, 50% women, age 28-30 years) were invited from an ongoing cohort study, based on BMI and sex. BMI-strata were: BMI <25, 25-30, >30 kg/m2, representing normal weight (NW), overweight (OW), and obesity (OB). Participants underwent cardiac computed tomography to detect coronary artery calcification, measures of body composition, blood pressure measurements, and a comprehensive panel of circulating cardiometabolic risk markers. RESULTS: No significant coronary artery calcifications were detected in this study. Minor differences in median levels of traditional risk markers were detected across BMI-strata, for example, total cholesterol (men- NW: 4.7 (4.3-5.1) and OB: 4.8 (4.2-5.6) mmol/L, p = 0.58; women- NW: 4.3 (3.9-4.8) and OB: 4.7 (4.2-5.3) mmol/L, p = 0.016), whereas substantial differences were seen in markers of inflammation and glucose metabolism, for example, high sensitive CRP (men- NW: 0.6 (0.3-1.1) and OB: 2.8 (1.5-4.0) mg/L, p < 0.001; women- NW: 0.7 (0.3-1.7) and OB: 4.0 (2.2-7.8) mg/L, p < 0.001) and insulin (men- NW: 47.0 (35.0-59.0) and OB: 113.5 (72.0-151.0) pmol/L, p < 0.001; women- NW: 44.0 (35.0-60.0) and OB: 84.5 (60.0-126.0) pmol/L, p < 0.001). CONCLUSION: In young adults, obesity is associated with an early onset insulin resistance and inflammatory response prior to development of coronary artery calcification and deterioration of lipid profiles.