cardiovascular disease risk factors in five-year-old urban South African children - the Birth to Ten study.
Steyn K, De Wet T, Richter L, Cameron N, Levitt NS, Morrell C.
S Afr Med J 2000; 90(7): 719-726.
Abstract

Background
A birth cohort study, the Birth to Ten study (BTT) commenced in the greater Johannesburg/Soweto metropole in South Africa in 1990. The overall BTT project collected antenatal, birth and early development information on these children. The data also included information that could help identify factors related to the emergence of CVD risk factors in children.

Objective
To determine cardiovascular diseases (CVD) risk profiles and their determinants in 5-year-old children living in an urban environment in South Africa.

Methods
Demographic and birth characteristics were collated on a sample of 964 five-year-old children whose parents agreed to have blood samples collected. The children's height and weight were measured using standardised procedures; blood pressure was measured with a Dinamap Vital Signs Monitor and a non-fasting blood sample drawn for lipid determinations. Exposure to tobacco smoke and additional health-related questions were obtained by interview.

Results
No differences were found between the birth weight and gestational age of the 5-year CVD participants and the remainder of the children studied at birth. The systolic blood pressure (BP) was significantly different between ethnic groups, with the BP of the black children being significantly higher than that of the Indian and white children and the diastolic BP of black children was also the highest. White children had the highest mean total cholesterol (TC) and low-density lipoprotein cholesterol (LDLC) levels, which were significantly higher than those in the black community. The coloured children's TC level was also significantly lower than that of the whites and the LDLC level of the Indian children significantly higher than that of the blacks. Overall, (64%) of the children were exposed to environmental tobacco smoke (ETS), with the white group having the lowest rate (45% exposed to ETS). The coloured children were most frequently exposed to ETS with 40.6% of them having primary caregivers smoking, and of these children 42% lived in homes with two or more smokers.

Conclusions
Tobacco control legislation will protect South Africans against tobacco sales promotions. This would be the first step towards moving chronic disease prevention, health promotion and appropriate care for chronic diseases and their risk factors higher on the South African health priority list. The groups of children studied, carried differing, but significant levels of CVD risk. This suggests that the promotion of a healthy lifestyle should start in childhood and should be targeted to the risk factors found in each group.