CIMT and cardiovascular risk in five-year-old children in a low socioeconomic population exposed to alcohol and nicotine during pregnancy: a case-control study
Cardiovascular diseases (CVD) are among the top 10 causes of death in all ages in South Africa. The prevalence of maternal smoking and alcohol consumption during pregnancy is alarmingly high in South Africa. In utero exposure to nicotine and alcohol may cause CVD later in life. There is a global need for early detection of CVD especially those vulnerable during early childhood, to prevent the development of CVD risk factors in adulthood. The aim of this study was to compare CVD risk in five-year-old children from a low socio-economic population with in utero dual exposure to nicotine and alcohol and in utero nicotine exposure by measuring carotid intima-media thickness (cIMT), anthropometric measurements and clinical measurements including blood pressure. A case-control study was conducted on 468 children at five years old through interviews to collect data on demographic characteristics and health statistics. The cIMT was measured using B-mode ultrasonography. Anthropometric measurements were taken such as skinfold thickness, waist circumference, height and weight to calculate Body Mass Index (BMI). Blood pressure measurements such as systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP) and heart rate (HR) were taken. The data was analysed using SPSS version 26. Descriptive and inferential statistics (Spearman’s correlations, non-parametric partial correlations), Kruskal-Wallis H, Chi-square tests and logistic regression were used for statistical analysis. Results showed a significantly higher right cIMT (RcIMT) (0.36 ± 0.05 mm; P < 0.01) in children with in utero exposure to nicotine and alcohol during pregnancy and a higher RcIMT in males (0.37 ± 0.06 mm; P < 0.01) with in utero dual exposure to nicotine and alcohol when compared to females. A significant association was found between in utero dual exposure to nicotine and alcohol and a high RcIMT, specifically in females at five years old after the adjustment for confounders (B= -1.618, P = 0.002). Consequently, females in the dual exposed group were 7.6 times more likely to exhibit higher RcIMT with a relative risk of 2.6 times greater to children with no exposure. Females also had significantly higher SBP (U= 3829.50, p <0.01), DBP (U= 3527.50, p <0.05), MAP (U= 3561.00, p <0.05) and HR (U= 3887.50, p <0.01) in the dual exposed group. Cardiovascular risk factors were modestly prevalent at five years old in children with in utero teratogen exposures. However, increased adiposity indices were not observed in this population at five years old and were not associated with teratogen exposures. This may indicate that dual exposure to nicotine and alcohol has a significant effect on the intima-media thickness of the carotid arteries in children, but not necessarily on central and peripheral adiposity at five years old. Therefore, CVD risk factors need to be identified early in children in low socioeconomic regions with in utero exposure to nicotine and alcohol to prevent CVD later in life.