John M Pettifor
Biographic Data
| ID | 4303595 |
|---|---|
| NAME | John M Pettifor |
| GIVEN NAMES | John M |
| FAMILY NAME | Pettifor |
| SIGNATURE | PETTIFOR J M |
| AFFILIATIONS | University of the Witwatersrand |
| ORCID | 0000-0003-1155-0334 |
| VERIFIED | Yes |
| TOTAL WORKS | 22 |
| TOTAL CITATIONS | 11 |
| AUTHOR COUNT | 22 |
| EDITOR COUNT | 0 |
| FIRST PUBLICATION YEAR | 1989 |
| LATEST PUBLICATION YEAR | 2021 |
| H-INDEX | 2 |
Adolescent growth and BMI and their associations with early childhood growth in an urban South African cohort
OBJECTIVES: The timing and magnitude of adolescent growth may be influenced by ethnicity and early life factors. We aimed to (a) characterize ethnic differences in the magnitude, timing, and intensity of adolescent growth in height, weight, and BMI; (b) assess the effect of early childhood growth on adolescent growth in black children. METHODS: Data were from the Birth to Twenty Plus cohort (Bt20+) in Johannesburg, South Africa (n = 3273). Height…
The prevalence of malnutrition and growth percentiles for urban South African children
The growth percentiles show that young South African urban black females are experiencing general but not central obesity due to a secular change which is faster in weight than height. High levels of undernutrition persist alongside high levels of over-nutrition with adolescence being a critical period for the upsurge in obesity in females. Early intervention is needed to combat the rise in obesity
Sanitation and diarrhoea in infancy and CRP level at 18 years
Background: Cardiometabolic disease is associated with chronic low-grade inflammation. While low birthweight, childhood stunting and rapid weight gain predict higher adult high-sensitivity C-reactive protein (hs-CRP) concentrations, associations between childhood infections and adulthood CRP are inconsistent.Aim: To assess the associations between sanitation, diarrhoea and a combined score of both from birth to age 2 years and hs-CRP at age 18 ye…
Life History theory hypotheses on child growth
Life history theory integrates ecological, physiological, and molecular layers within an evolutionary framework to understand organisms’ strategies to optimize survival and reproduction. Two life history hypotheses and their implications for child growth, development, and health (illustrated in the South African context) are reviewed here. One hypothesis suggests that there is an energy trade‐off between linear growth and brain growth. Undernutri…
Postnatal growth velocity and overweight in early adolescents
OBJECTIVES: To compare growth velocity of two African child cohorts and examine the relationship between postnatal growth velocity in infancy/early childhood and the risk of overweight/stunting in early adolescence. METHODS: The study used data from two child cohorts from urban (Birth to Twenty Cohort, South Africa) and rural (Lungwena Child Survival Study, Malawi) African settings. Mixed effect modelling was used to derive growth and peak growth…
Application of Intervention Mapping to develop a community-based health promotion pre-pregnancy intervention for adolescent girls in rural South Africa
The Ntshembo intervention is novel, both in SA and globally, as it is: (1) based on strong evidence, extensive formative work and best practice from evaluated interventions; (2) combines theory with evidence to inform intervention components; (3) includes multiple domains of influence (community through to the individual); (4) focuses on an at-risk target group; and (5) embeds within existing and planned health service priorities in SA
Physical activity and sedentary behavior among adolescents in rural South Africa
In this study of rural South African adolescent boys and girls, SES at the maternal, household and community level independently predicted time spent in sedentary behaviors, and school and club MVPA. This study provides local data that can be used to develop health promotion strategies specific to this community, and other similar communities in developing countries
Dietary intake and body composition in HIV-positive and -negative South African women
Objective The present paper examines dietary intake and body composition in antiretroviral (ARV)-naïve HIV-positive compared with HIV-negative South African women, as well as the impact of disease severity on these variables. Design Baseline data from a longitudinal study assessing bone health in HIV-negative and HIV-positive premenopausal South African women over 18 years of age were used. Anthropometry and body composition, measured by dual ene…
In urban South Africa, 16 year old adolescents experience greater health equality than children
Investigation into longitudinal dietary behaviours and household socio-economic indicators and their association with BMI Z -score and fat mass in South African adolescents
Objective The present study aimed to assess the relationship between dietary habits, change in socio-economic status and BMI Z -score and fat mass in a cohort of South African adolescents. Design In the longitudinal study, data were collected at ages 13, 15 and 17 years on a birth cohort who have been followed since 1990. Black participants with complete dietary habits data (breakfast consumption during the week and at weekends, snacking while wa…
Associations Between Household and Neighbourhood Socioeconomic Status and Systolic Blood Pressure Among Urban South African Adolescents
Factors resulting in high risk for cardiovascular disease have been well studied in high income countries, but have been less well researched in low/middle income countries. This is despite robust theoretical evidence of environmental transitions in such countries which could result in biological adaptations that lead to increased hypertension and cardiovascular disease risk. Data from the South African Birth to Twenty cohort, Bone Health sub-sam…
Factors influencing the vitamin D status of 10-year-old urban South African children
Objective Assessment of vitamin D status in a cohort of healthy 10-year-old urban children and the factors that influence vitamin D status in these children. Design A cross-sectional study. Blood samples were collected across four seasons of the year for the biochemical determination of serum 25-hydroxyvitamin D [25(OH)D]. Anthropometric measurements (height and weight), BMI and total fat and lean mass (determined by the dual energy X-ray absorpt…
Predictors of adolescent weight status and central obesity in rural South Africa
Objective To investigate predictors of adolescent obesity in rural South Africa. Design Cross-sectional study. Height, weight and waist circumference were measured using standard procedures. Overweight and obesity in adolescents aged 10–17 years were assessed using the International Obesity Taskforce cut-offs, while the WHO adult cut-offs were used for participants aged 18–20 years. Waist-to-height ratio of >0·5 defined central obesity in those a…
The prevalence of stunting, overweight and obesity, and metabolic disease risk in rural South African children
The study highlights that in transitional societies, early stunting and adolescent obesity may co-exist in the same socio-geographic population. It is likely that this profile relates to changes in nutrition and diet, but variation in factors such as infectious disease burden and physical activity patterns, as well as social influences, need to be investigated. As obesity and adult short stature are risk factors for metabolic syndrome and Type 2 …
Age at menarche and the evidence for a positive secular trend in urban South Africa
Menarcheal age was estimated for 287 (188 Black; 99 White) urban South African girls born in Soweto‐Johannesburg in 1990. The median menarcheal age for Blacks was 12.4 years (95% confidence interval (CI) 12.2, 12.6) and 12.5 years (95% CI 11.7, 13.3) for Whites. Data from six studies of menarcheal age, including the current study, were analyzed to examine the evidence for a secular trend between 1956 and 2004 in urban South African girls. There w…
Is puberty starting earlier in urban South Africa
Age at the initation of pubertal development was estimated for 401 Black (212 boys) and 206 White (100 boys) urban South African adolescents born in Soweto‐Johannesburg in 1990. Average age at the initation of puberty, assessed by age at the transition from Tanner Stage 1 to Tanner Stage 2 for breast/genitalia or pubic hair development ranged between 9.8 and 10.5 years. There were no statistically significant differences in age at initiation betw…
Approaches for assessing the role of household socioeconomic status on child anthropometric measures in urban South Africa
The objectives of this article were to compare the variance explained in anthropometric outcomes when using individual measures of socioeconomic status (SES) versus different approaches to create SES indices within the urban African context, and to examine the influence of SES measured during infancy on child anthropometric outcomes at 7/8 years. Data from the 1990 Birth‐to‐Twenty cohort study set in Johannesburg‐Soweto, South Africa, were used (…
Secular trends in skeletal maturity in South Africa
Significant secular increases in the skeletal maturity of urban black South African children occurred between 1962 and 2001. Non-significant increases were seen in white children. The significant secular increases were concordant with increases in stature and adiposity during this period. The increase in skeletal maturity may reflect the removal of growth constraint, particularly in black children
Implications of adopting the WHO 2006 Child Growth Standards
Discourse on the implementation of WHO 2006 and the impact on the primary health care system and public health monitoring in South Africa is needed, and sufficient planning is critical around not only the implementation of WHO 2006 but also maintaining comparability with historical malnutrition data
Cohort Profile
The late 1980s were a period of profound sociopolitical change in South Africa. It was clear that the Apartheid state was crumbling and amongst acts of civil disobedience which characterized the struggle Black Africansy began to disregard restrictive legislation that constrained where they lived and worked. Very rapid unplanned urbanization began and shanty towns mushroomed around formerly White cities and towns. It was anticipated that this rapi…
Effect of ethnicity and sex on the growth of the axial and appendicular skeleton of children living in a developing country
Bones in the axial and appendicular skeletons exhibit heterogeneous growth patterns between different ethnic and sex groups. However, the influence of this differential growth on the expression of bone mineral content is not yet established. The aims of the present study were to investigate: 1) whether there are ethnic and sex differences in axial and appendicular dimensions of South African children; and 2) whether regional segment length is a b…
Cases and Comments
Effect of ethnicity and sex on the growth of the axial and appendicular skeleton of children living in a developing country
Bones in the axial and appendicular skeletons exhibit heterogeneous growth patterns between different ethnic and sex groups. However, the influence of this differential growth on the expression of bone mineral content is not yet established. The aims of the present study were to investigate: 1) whether there are ethnic and sex differences in axial and appendicular dimensions of South African children; and 2) whether regional segment length is a b…
Life History theory hypotheses on child growth
Life history theory integrates ecological, physiological, and molecular layers within an evolutionary framework to understand organisms’ strategies to optimize survival and reproduction. Two life history hypotheses and their implications for child growth, development, and health (illustrated in the South African context) are reviewed here. One hypothesis suggests that there is an energy trade‐off between linear growth and brain growth. Undernutri…
Cases and Comments
Effect of ethnicity and sex on the growth of the axial and appendicular skeleton of children living in a developing country
Bones in the axial and appendicular skeletons exhibit heterogeneous growth patterns between different ethnic and sex groups. However, the influence of this differential growth on the expression of bone mineral content is not yet established. The aims of the present study were to investigate: 1) whether there are ethnic and sex differences in axial and appendicular dimensions of South African children; and 2) whether regional segment length is a b…
Cohort Profile
The late 1980s were a period of profound sociopolitical change in South Africa. It was clear that the Apartheid state was crumbling and amongst acts of civil disobedience which characterized the struggle Black Africansy began to disregard restrictive legislation that constrained where they lived and worked. Very rapid unplanned urbanization began and shanty towns mushroomed around formerly White cities and towns. It was anticipated that this rapi…
Implications of adopting the WHO 2006 Child Growth Standards
Discourse on the implementation of WHO 2006 and the impact on the primary health care system and public health monitoring in South Africa is needed, and sufficient planning is critical around not only the implementation of WHO 2006 but also maintaining comparability with historical malnutrition data
Age at menarche and the evidence for a positive secular trend in urban South Africa
Menarcheal age was estimated for 287 (188 Black; 99 White) urban South African girls born in Soweto‐Johannesburg in 1990. The median menarcheal age for Blacks was 12.4 years (95% confidence interval (CI) 12.2, 12.6) and 12.5 years (95% CI 11.7, 13.3) for Whites. Data from six studies of menarcheal age, including the current study, were analyzed to examine the evidence for a secular trend between 1956 and 2004 in urban South African girls. There w…
Is puberty starting earlier in urban South Africa
Age at the initation of pubertal development was estimated for 401 Black (212 boys) and 206 White (100 boys) urban South African adolescents born in Soweto‐Johannesburg in 1990. Average age at the initation of puberty, assessed by age at the transition from Tanner Stage 1 to Tanner Stage 2 for breast/genitalia or pubic hair development ranged between 9.8 and 10.5 years. There were no statistically significant differences in age at initiation betw…
Approaches for assessing the role of household socioeconomic status on child anthropometric measures in urban South Africa
The objectives of this article were to compare the variance explained in anthropometric outcomes when using individual measures of socioeconomic status (SES) versus different approaches to create SES indices within the urban African context, and to examine the influence of SES measured during infancy on child anthropometric outcomes at 7/8 years. Data from the 1990 Birth‐to‐Twenty cohort study set in Johannesburg‐Soweto, South Africa, were used (…
Secular trends in skeletal maturity in South Africa
Significant secular increases in the skeletal maturity of urban black South African children occurred between 1962 and 2001. Non-significant increases were seen in white children. The significant secular increases were concordant with increases in stature and adiposity during this period. The increase in skeletal maturity may reflect the removal of growth constraint, particularly in black children
The prevalence of stunting, overweight and obesity, and metabolic disease risk in rural South African children
The study highlights that in transitional societies, early stunting and adolescent obesity may co-exist in the same socio-geographic population. It is likely that this profile relates to changes in nutrition and diet, but variation in factors such as infectious disease burden and physical activity patterns, as well as social influences, need to be investigated. As obesity and adult short stature are risk factors for metabolic syndrome and Type 2 …
Factors influencing the vitamin D status of 10-year-old urban South African children
Objective Assessment of vitamin D status in a cohort of healthy 10-year-old urban children and the factors that influence vitamin D status in these children. Design A cross-sectional study. Blood samples were collected across four seasons of the year for the biochemical determination of serum 25-hydroxyvitamin D [25(OH)D]. Anthropometric measurements (height and weight), BMI and total fat and lean mass (determined by the dual energy X-ray absorpt…
Predictors of adolescent weight status and central obesity in rural South Africa
Objective To investigate predictors of adolescent obesity in rural South Africa. Design Cross-sectional study. Height, weight and waist circumference were measured using standard procedures. Overweight and obesity in adolescents aged 10–17 years were assessed using the International Obesity Taskforce cut-offs, while the WHO adult cut-offs were used for participants aged 18–20 years. Waist-to-height ratio of >0·5 defined central obesity in those a…
Associations Between Household and Neighbourhood Socioeconomic Status and Systolic Blood Pressure Among Urban South African Adolescents
Factors resulting in high risk for cardiovascular disease have been well studied in high income countries, but have been less well researched in low/middle income countries. This is despite robust theoretical evidence of environmental transitions in such countries which could result in biological adaptations that lead to increased hypertension and cardiovascular disease risk. Data from the South African Birth to Twenty cohort, Bone Health sub-sam…
In urban South Africa, 16 year old adolescents experience greater health equality than children
Investigation into longitudinal dietary behaviours and household socio-economic indicators and their association with BMI Z -score and fat mass in South African adolescents
Objective The present study aimed to assess the relationship between dietary habits, change in socio-economic status and BMI Z -score and fat mass in a cohort of South African adolescents. Design In the longitudinal study, data were collected at ages 13, 15 and 17 years on a birth cohort who have been followed since 1990. Black participants with complete dietary habits data (breakfast consumption during the week and at weekends, snacking while wa…
Postnatal growth velocity and overweight in early adolescents
OBJECTIVES: To compare growth velocity of two African child cohorts and examine the relationship between postnatal growth velocity in infancy/early childhood and the risk of overweight/stunting in early adolescence. METHODS: The study used data from two child cohorts from urban (Birth to Twenty Cohort, South Africa) and rural (Lungwena Child Survival Study, Malawi) African settings. Mixed effect modelling was used to derive growth and peak growth…
Application of Intervention Mapping to develop a community-based health promotion pre-pregnancy intervention for adolescent girls in rural South Africa
The Ntshembo intervention is novel, both in SA and globally, as it is: (1) based on strong evidence, extensive formative work and best practice from evaluated interventions; (2) combines theory with evidence to inform intervention components; (3) includes multiple domains of influence (community through to the individual); (4) focuses on an at-risk target group; and (5) embeds within existing and planned health service priorities in SA
Physical activity and sedentary behavior among adolescents in rural South Africa
In this study of rural South African adolescent boys and girls, SES at the maternal, household and community level independently predicted time spent in sedentary behaviors, and school and club MVPA. This study provides local data that can be used to develop health promotion strategies specific to this community, and other similar communities in developing countries
Dietary intake and body composition in HIV-positive and -negative South African women
Objective The present paper examines dietary intake and body composition in antiretroviral (ARV)-naïve HIV-positive compared with HIV-negative South African women, as well as the impact of disease severity on these variables. Design Baseline data from a longitudinal study assessing bone health in HIV-negative and HIV-positive premenopausal South African women over 18 years of age were used. Anthropometry and body composition, measured by dual ene…
Life History theory hypotheses on child growth
Life history theory integrates ecological, physiological, and molecular layers within an evolutionary framework to understand organisms’ strategies to optimize survival and reproduction. Two life history hypotheses and their implications for child growth, development, and health (illustrated in the South African context) are reviewed here. One hypothesis suggests that there is an energy trade‐off between linear growth and brain growth. Undernutri…
The prevalence of malnutrition and growth percentiles for urban South African children
The growth percentiles show that young South African urban black females are experiencing general but not central obesity due to a secular change which is faster in weight than height. High levels of undernutrition persist alongside high levels of over-nutrition with adolescence being a critical period for the upsurge in obesity in females. Early intervention is needed to combat the rise in obesity
Sanitation and diarrhoea in infancy and CRP level at 18 years
Background: Cardiometabolic disease is associated with chronic low-grade inflammation. While low birthweight, childhood stunting and rapid weight gain predict higher adult high-sensitivity C-reactive protein (hs-CRP) concentrations, associations between childhood infections and adulthood CRP are inconsistent.Aim: To assess the associations between sanitation, diarrhoea and a combined score of both from birth to age 2 years and hs-CRP at age 18 ye…
Adolescent growth and BMI and their associations with early childhood growth in an urban South African cohort
OBJECTIVES: The timing and magnitude of adolescent growth may be influenced by ethnicity and early life factors. We aimed to (a) characterize ethnic differences in the magnitude, timing, and intensity of adolescent growth in height, weight, and BMI; (b) assess the effect of early childhood growth on adolescent growth in black children. METHODS: Data were from the Birth to Twenty Plus cohort (Bt20+) in Johannesburg, South Africa (n = 3273). Height…
Medicine (20 works) · Demography (18 works) · Obesity, Physical Activity, Diet (13 works) · Child Nutrition and Water Access (12 works) · Cohort (11 works) · Internal Medicine (11 works) · Demography (10 works) · Birth, Development, and Health (9 works) · Environmental health (8 works) · Obesity (8 works)