Mediators in the effect of maternal alcohol consumption and cigarette smoking on cardiometabolic risk factors in 10–14-year-old adolescents

Abstract Aim To identify potential mediators of the development of cardiometabolic risk factors in adolescents exposed to cigarette smoking and alcohol in utero . Methods A total of 307 adolescents aged 10–14 years who were enrolled in urban schools in Cape Town, South Africa, were evaluated. Anthropometric measurements, lipid profiles and blood pressure measurements were obtained from 307 adolescents aged 10–14 years in a low-socioeconomic community. Statistical analysis included nonparametric tests, as most of the data were not normally distributed. Mediation analyses were conducted via linear regression and the PROCESS Macros models. Results Maternal cigarette smoking during pregnancy had a significant direct effect on childhood SBP after adjusting for covariates. However, the indirect effect of BMI on SBP was significant, suggesting a 1-unit increase in BMI leading to a 1.38 mmHg increase in SBP. In addition, BW was not associated with adolescent SBP. Moreover, adolescent BMI mediated the effect of maternal cigarette smoking on overweight/obesity, rather than the direct effect of maternal cigarette smoking. Additionally, BW was significantly and positively associated with BMI but not with adolescent overweight/obesity in this cohort. Maternal smoking was also directly associated with low HDL cholesterol in boys only. Conclusion BMI was identified as the main mediator in the effect of maternal smoking on adolescent SBP, overweight and obesity. Moreover, in utero exposure was not significantly associated with higher BMI or higher BP measurements, obesity or overweight. Cardiometabolic risk in terms of higher BMI/overweight and obesity was lower than those with no exposure.