Browsing by Author "Sanushka Naidoo"

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    Are cardiovascular health measures heritable across three generations of families in Soweto, South Africa? A cross-sectional analysis using the random family method
    (2022-09-23) Lisa J Ware; Innocent Maposa; Andrea Kolkenbeck-Ruh; Shane A Norris; Larske Soepnel; Simone Crouch; Juliana Kagura; Sanushka Naidoo; Wayne Smith; Justine Davies
    Objectives: Cardiovascular disease is increasing in many low and middle-income countries, including those in Africa. To inform strategies for the prevention of cardiovascular disease in South Africa, we sought to determine the broad heritability of phenotypic markers of cardiovascular risk across three generations. Design: A cross-sectional study conducted in a longitudinal family cohort. Setting: Research unit within a tertiary hospital in a historically disadvantaged, large urban township of South Africa. Participants: 195 individuals from 65 biological families with all three generations including third-generation children aged 4-10 years were recruited from the longest running intergenerational cohort study in Africa, the Birth to Twenty Plus cohort. All adults (grandparents and parents) were female while children were male or female. Primary and secondary outcome measures: The primary outcome was heritability of blood pressure (BP; brachial and central pressures). Secondary outcomes were heritability of arterial stiffness (pulse wave velocity), carotid intima media thickness (cIMT) and left ventricular mass indexed to body surface area (LVMI). Results: While no significant intergenerational relationships of BP or arterial stiffness were found, there were significant relationships in LVMI across all three generations (p<0.04), and in cIMT between grandparents and parents (p=0.0166). Heritability, the proportion of phenotypic trait variation attributable to genetics, was estimated from three common statistical methods and ranged from 23% to 44% for cIMT and from 21% to 39% for LVMI. Conclusions: Structural indicators of vascular health, which are strong markers of future clinical cardiovascular outcomes, transmit between generations within African families. Identification of these markers in parents may be useful to trigger assessments of preventable risk factors for cardiovascular disease in offspring.
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    Obesity, hypertension, and tobacco use associated with left ventricular remodeling and hypertrophy in South African women: Birth to Twenty Plus Cohort
    (2022) Andrea Kolkenbeck‑Ruh; Larske M. Soepnel; Simone H. Crouch; Sanushka Naidoo; Wayne Smith; Shane A. Norris; Justine Davies; Lisa J. Ware
    Background: Left ventricular hypertrophy (LVH) is a marker of increased risk in developing future life-threatening cardiovascular disease (CVD), however, it is unclear how CVD risk factors, such as obesity, blood pressure (BP), and tobacco use, are associated with left ventricular (LV) remodeling and LVH in urban African populations. Therefore, we aimed to identify the prevalence of LVH as well as the health factors associated with LV remodeling and LVH, within black South African adult women and their pre-pubescent children. Methods: Black female adults (n=123; age: 29–68 years) and their children (n=64; age: 4–10; 55% female) were recruited from the Birth to Twenty Plus Cohort in Soweto, South Africa. Tobacco and alcohol use, physical activity, presence of diabetes mellitus, heart disease, and medication were self-reported. Height, weight, and blood pressure were measured in triplicate to determine the prevalence of obesity and hypertension respectively. Echocardiogra‑ phy was used to assess LV mass at end-diastole, based on linear measurements, and indexed to body surface area to determine LVH. Results: Hypertension and obesity prevalences were 35.8% and 59.3% for adults and 45.3% and 6.3% for children. Self-reported tobacco use in adults was 22.8%. LVH prevalence was 35.8% in adults (75% eccentric: 25% concentric), and 6.3% in children. Concentric remodeling was observed in 15.4% of adults, however, concentric remodeling was only found in one child. In adults, obesity [OR: 2.54 (1.07–6.02; p=0.02)] and hypertension [3.39 (1.08–10.62; p=0.04)] signifcantly increased the odds of LVH, specifcally eccentric LVH, while concentric LVH was associated with selfreported tobacco use [OR: 4.58 (1.18–17.73; p=0.03)]. Although no logistic regression was run within children, of the four children LVH, three had elevated blood pressure and the child with normal blood pressure was overweight. Conclusions: The association between obesity, hypertension, tobacco use, and LVH in adults, and the 6% prevalence of LVH in children, calls for stronger public health eforts to control risk factors and monitor children who are at risk.