Parker-Mansoor, Sabreen2026-07-062026-07-062025https://hdl.handle.net/10566/24852Background: The global and local rise in morbidity and mortality related to cardiovascular and cardiometabolic disease presents a major public health concern. In South Africa, lowincome communities are disproportionately affected due to limited access to healthcare, nutritious food, physical activity, education, and increased exposure to modifiable risk factors like tobacco use. These socioeconomic challenges contribute to the increasing burden of obesity, particularly among youth. Obesity and related cardiometabolic risk factors tend to track from childhood into adulthood, highlighting the importance of addressing adolescent health. While rapid weight gain (RWG) in infancy and early childhood has been independently associated with obesity and adverse cardiometabolic outcomes, limited research has explored how early and late RWG influence adolescent cardiometabolic health in South African populations. Additionally, prenatal nicotine exposure is a well-established risk factor for increased adiposity, cardiometabolic dysfunction, and its connection to infant RWG. However, the sex-specific impacts of prenatal nicotine exposure and RWG during adolescence remains underexplored. This study aimed to determine whether RWG in pubertal adolescents was associated with an increased risk of adolescent obesity and other cardiometabolic risk factors, such as elevated blood pressure, increased waist circumference (WC), greater skinfold thickness, and its relation to in utero nicotine exposure. Methods: This study followed a casecontrol design on 100 adolescents from a low socio-economic income setting in Cape Town, South Africa. Interviews were conducted with guardians and participants to collect health and lifestyle information regarding physical activity, diet, smoking during pregnancy, and SES. Anthropometric measurements were taken, such as weight and height for body mass index (BMI) calculation, triceps and subscapular skinfold thickness (SFT), and WC. Blood pressure measurements such as systolic and diastolic blood pressure, mean arterial pressure (MAP), and heart rate were taken from adolescent participants. Retrospective data was collected using the weight-for-age charts from each participant's Road to Health clinic booklets for RWG calculation. Data was analysed using SPSS version 30.enRapid weight gainCardiometabolic riskAdolescent obesityprenatal nicotine exposureSouth AfricaThesis