Prevalence and associated risk factors for elevated blood pressure in young adults in South Africa

BACKGROUND

Sub-Saharan Africa has been shown to have a high prevalence of hypertension (58% in rural black South Africans) with an accelerated course ending in end-stage renal disease. We sought to determine whether the prevalence of elevated blood pressure (EBP) in early adulthood was associated with any risk factors and/or renal target-organ damage in young adulthood, which could prevent development of these cardiorenal sequelae.

METHODS

Data including risk factors for hypertension and markers of kidney damage were collected from young adults (n = 933; age 28 years; 52% female) participating in the Birth to Twenty Plus (BT20) cohort in Soweto, South Africa. Blood pressure was measured on one occasion.

RESULTS

Fifty-four per cent of the study sample had EBP with more men affected (62%) than women (47%) (p < 0.001). Body mass index (BMI), hyperuricaemia and albuminuria had significant associations with EBP in men. In women, BMI, hyperuricaemia and a self-reported history of gestational hypertension had significant associations.

CONCLUSIONS

Our findings suggest that the pathophysiology of EBP in young adults differs between the genders and highlights a number of modifiable factors in its development.

The association between the timing, intensity and magnitude of adolescent growth and body composition in early adulthood

OBJECTIVES

There's paucity of longitudinal studies assessing the role of adolescent growth on adult body composition in developing countries. The aims of this study were to assess the association between adolescent change in height, weight and BMI and early adult height, weight, body fat and lean mass.

METHODS

Magnitude, timing and intensity of height, weight and BMI growth were modelled for participants from the Birth to Thirty (Bt30) cohort (7-23 years). Early adult height, weight, BMI and DXA-derived body composition were obtained 1881 black participants (21-24 years). Linear regression analyses were used to assess associations.

RESULTS

Adolescents with an earlier onset of puberty were heavier in childhood and had an earlier timing and faster weight gain velocity in late adolescence. The intensity of adolescent weight gain was positively associated with adult BMI and fat mass index (FMI) in females. Early timing of adolescent BMI gain was associated with increased weight and BMI in adult females and FMI in adult males. Achieving peak weight velocity around age at peak height velocity was associated with lower BMI and fat mass in both sexes.

CONCLUSION

This study confirms the adverse consequences of excessive weight gain prior to puberty, which is associated with an earlier and faster resurgence in weight gain velocity in early adulthood. Factors that contribute to an asynchronous timing of ages of peak weight and peak height velocities may accentuate the risk of adult obesity.

The impact of HIV and ART exposure during pregnancy on fetal growth: a prospective study in a South African cohort

BACKGROUND

In utero exposure to human immunodeficiency virus (HIV) and antiretroviral (ART) is associated with adverse birth outcomes, which are often attributed to alterations in placental morphology. This study used structural equation models (SEMs) to examine the impact of HIV and ART exposure on fetal growth outcomes and whether these associations are mediated by placental morphology in urban-dwelling Black South African women.

METHODS

This prospective cohort study included pregnant women living with HIV (WLWH, n = 122) and not living with HIV (WNLWH, n = 250) that underwent repeated ultrasonography during pregnancy, and at delivery, to determine fetal growth parameters in Soweto, South Africa. The size and the velocity of fetal growth measures (i.e., head and abdominal circumference, biparietal diameter, and femur length) were calculated using the Superimposition by Translation and Rotation. Placenta digital photographs taken at delivery were used to estimate morphometric parameters and trimmed placental weight was measured. All WLWH were receiving ART for the prevention of vertical transmission of HIV.

RESULTS

A trend towards a lower placental weight and significantly shorter umbilical cord length was reported in WLWH compared to their counterparts. After sex stratification, umbilical cord length was significantly shorter in males born to WLWH than in male fetuses born to WNLWH (27.3 (21.6-32.8) vs. 31.4 (25.0-37.0) cm, p = 0.015). In contrast, female fetuses born to WLWH had lower placental weight, birth weight (2.9 (2.3-3.1) vs. 3.0 (2.7-3.2) kg), and head circumference (33 (32-34) vs. 34 (33-35) cm) than their counterparts (all p ≤ 0.05). The SEM models showed an inverse association between HIV and head circumference size and velocity in female fetuses. In contrast, HIV and ART exposure was positively associated with femur length growth (both size and velocity) and abdominal circumference velocity in male fetuses. None of these associations appeared to be mediated via placental morphology.

CONCLUSION

Our findings suggest that HIV and ART exposure directly affects head circumference growth in females and abdominal circumference velocity in male fetuses; but may improve femur length growth in male fetuses only.

Body composition reference charts for infants from birth to 24 months: Multicenter Infant Body Composition Reference Study

BACKGROUND

Body composition assessment in the first 2 y of life provides important insights into child nutrition and health. The application and interpretation of body composition data in infants and young children have been challenged by a lack of global reference data.

OBJECTIVES

We aimed to develop body composition reference charts of infants aged 0-6 mo based on air displacement plethysmography (ADP) and those aged 3-24 mo based on total body water (TBW) by deuterium dilution (DD).

METHODS

Body composition was assessed by ADP in infants aged 0-6 mo from Australia, India, and South Africa. TBW using DD was assessed for infants aged 3-24 mo from Brazil, Pakistan, South Africa, and Sri Lanka. Reference charts and centiles were constructed for body composition using the lambda-mu-sigma method.

RESULTS

Sex-specific reference charts were produced for FM index (FMI), FFM index (FFMI), and percent FM (%FM) for infants aged 0-6 mo (n = 470 infants; 1899 observations) and 3-24 mo (n = 1026 infants; 3690 observations). When compared with other available references, there were observable differences but similar patterns in the trajectories of FMI, FFMI, and %FM.

CONCLUSIONS

These reference charts will strengthen the interpretation and understanding of body composition in infants across the first 24 mo of life.

A comparison of paediatric hypertension clinical practice guidelines and their ability to predict adult hypertension in an African birth cohort

It remains unclear which paediatric hypertension clinical practice guideline (CPG) should be applied in an African population. We, therefore, aimed to compare commonly used CPG (2017 AAP, 2016 ESH, 2004 Fourth Report) developed in high-income countries for use in South African children at four paediatric ages (children: 5 years, 8 years; adolescents: 13 years, 17 years) to determine which best predicts elevated blood pressure (BP) in adulthood (22 years, 28 years). Moreover, the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for each specific paediatric CPG was calculated across the age points. The 2017 AAP definition identified more children and adolescents with hypertension when compared to the 2004 Fourth Report and 2016 ESH guidelines. In computed hazards ratios, ages 8 years to 17 years, all three paediatric CPG significantly predicted the risk of elevated BP in young adulthood (p ≤ 0.032). However, sensitivity to predict elevated BP at age 22 years for all CPG was generally low (17.0%-33.0%) with higher specificity (87.4%-93.1%). Sensitivity increased at age 28 years (51.4%-70.1%), while specificity decreased (52.8%-65.1%). Both PPV and NPV at both adult age points varied widely (17.9%-79.9% and 29.3%-92.5% respectively). The performance of these paediatric CPG in terms of AUC were not optimal at both adult age points, however, the 2017 AAP definition at age 17 years met an acceptable level of performance (AUC = 0.71). Our results, therefore, highlight the need for more research to examine if an African-specific CPG would better identify high-risk children to minimise their trajectory towards adult hypertension.

What values drive communities' nutrition priorities in a resource constrained urban area in South Africa?

BACKGROUND

Voices of under-resourced communities are recognised as important yet are often unheard in decisions about healthcare resource allocation. Deliberative public engagement can serve as an effective mechanism for involving communities in establishing nutrition priorities. This study sought to identify the priorities of community members of a South African township, Soweto, and describe the underlying values driving their prioritisation process, to improve nutrition in the first 1000 days of life.

METHODS

We engaged 54 community members (28 men and 26 women aged > 18 years) from Soweto. We conducted seven group discussions to determine how to allocate limited resources for prioritising nutrition interventions. We used a modified public engagement tool: CHAT (Choosing All Together) which presented 14 nutrition intervention options and their respective costs. Participants deliberated and collectively determined their nutritional priorities. Choices were captured quantitatively, while group discussions were audio-recorded. A thematic analysis was undertaken to identify the reasons and values associated with the selected priorities.

RESULTS

All groups demonstrated a preference to allocate scarce resources towards three priority interventions-school breakfast provisioning, six-months paid maternity leave, and improved food safety. All but one group selected community gardens and clubs, and five groups prioritised decreasing the price of healthy food and receiving job search assistance. Participants' allocative decisions were guided by several values implicit in their choices, such as fairness and equity, efficiency, social justice, financial resilience, relational solidarity, and human development, with a strong focus on children. Priority interventions were deemed critical to supporting children's optimal development and well-being, interrupting the intergenerational cycle of poverty and poor human development in the community.

CONCLUSION

Our study demonstrates how public engagement can facilitate the incorporation of community values and programmatic preferences into nutrition priority setting, enabling a responsive approach to local community needs, especially in resource constrained contexts. Findings could guide policy makers to facilitate more appropriate decisions and to improve nutrition in the first 1000 days of life.

A Cross-Sectional Study of the Associations between Biomarkers of Vitamin D, Iron Status, and Hemoglobin in South African Women of Reproductive Age: the Healthy Life Trajectories Initiative, South Africa

Background

Vitamin D deficiency and anemia impact the health of women of reproductive age. Evidence suggests an inverse relationship between serum vitamin D (25-hydroxyvitamin D [25(OH)D]) and anemia/iron deficiency, but less is known about these associations in women of reproductive age, in particular in a setting with a combined burden of micronutrient deficiency, food insecurity, and obesity.

Objective

We aimed to assess the associations between 25(OH)D and biomarkers of iron and anemia in a cohort of women of reproductive age from Soweto, South Africa. The prevalence of vitamin D deficiency was also assessed.

Methods

In this cross-sectional substudy of the Healthy Life Trajectories Initiative (HeLTI) South Africa pilot trial, 25(OH)D, iron markers (ferritin and soluble transferrin receptor [sTFR]), and altitude-adjusted hemoglobin (Hb) were measured in 493 women aged 18 to 25 years. Associations between iron deficiency/anemia and vitamin D status were evaluated using multivariable logistic regression, adjusting for confounders including fat mass index (FMI). Structural equation modeling (SEM) was performed to evaluate direct and indirect pathways between 25(OH)D, iron and anemia markers, and covariates.

Results

Of 493 participants, 136 (27.6%) had vitamin D insufficiency (25(OH)D ≥12-20 ng/mL), whereas 28 (5.6%) had vitamin D deficiency (<12 ng/mL). Anemia and iron deficiency were not significantly associated with vitamin D category (25(OH)D<20 ng/mL compared with ≥20 ng/mL) in multivariable logistic regression analyses. In SEM, log-transformed 25(OH)D was not significantly associated with Hb, ferritin, or sTFR, but it was significantly associated with season of data collection, hormonal contraceptive use, and FMI (total effects: B = 0.17, 95% CI: 0.104, 0.236, P < 0.001; B: 0.10, 95% CI: 0.041, 0.154, P < 0.001; B: -0.01, 95%CI: -0.016, -0.003, P = 0.003, respectively).

Conclusion

No significant association between vitamin D (25(OH)D), anemia (Hb), and iron markers was found. The inverse relationship between FMI and vitamin D status emphasizes the overlap between adiposity and micronutrient deficiencies in young South African women, exacerbating their risk of disease development.

Diabetes care cascade and associated factors in 10 700 middle-aged adults in four sub-Saharan African countries: a cross-sectional study

OBJECTIVES

We investigated progression through the care cascade and associated factors for people with diabetes in sub-Saharan Africa to identify attrition stages that may be most appropriate for targeted intervention.

DESIGN

Cross-sectional study.

SETTING

Community-based study in four sub-Saharan African countries.

PARTICIPANTS

10 700 individuals, aged 40-60 years.

PRIMARY AND SECONDARY OUTCOME MEASURES

The primary outcome measure was the diabetes cascade of care defined as the age-adjusted diabetes prevalence (self-report of diabetes, fasting plasma glucose (FPG) ≥7 mmol/L or random plasma glucose ≥11.1 mmol/L) and proportions of those who reported awareness of having diabetes, ever having received treatment for diabetes and those who achieved glycaemic control (FPG <7.2 mmol/L). Secondary outcome measures were factors associated with having diabetes and being aware of the diagnosis.

RESULTS

Diabetes prevalence was 5.5% (95% CI 4.4% to 6.5%). Approximately half of those with diabetes were aware (54%; 95% CI 50% to 58%); 73% (95% CI 67% to 79%) of aware individuals reported ever having received treatment. However, only 38% (95% CI 30% to 46%) of those ever having received treatment were adequately controlled. Increasing age (OR 1.1; 95% CI 1.0 to 1.1), urban residence (OR 2.3; 95% CI 1.6 to 3.5), hypertension (OR 1.9; 95% CI 1.5 to 2.4), family history of diabetes (OR 3.9; 95% CI 3.0 to 5.1) and measures of central adiposity were associated with higher odds of having diabetes. Increasing age (OR 1.1; 95% CI 1.0 to 1.1), semi-rural residence (OR 2.5; 95% CI 1.1 to 5.7), secondary education (OR 2.4; 95% CI 1.2 to 4.9), hypertension (OR 1.6; 95% CI 1.0 to 2.4) and known HIV positivity (OR 2.3; 95% CI 1.2 to 4.4) were associated with greater likelihood of awareness of having diabetes.

CONCLUSIONS

There is attrition at each stage of the diabetes care cascade in sub-Saharan Africa. Public health strategies should target improving diagnosis in high-risk individuals and intensifying therapy in individuals treated for diabetes.

Perceptions of the COVID-19 pandemic: a qualitative study with South African adults

INTRODUCTION

In South Africa, public perceptions of the COVID-19 pandemic and risk mitigation measures remain mixed. To better understand health behaviours in the context of COVID-19, a qualitative study was conducted, which aimed to investigate perceptions relating to the COVID-19 pandemic among the South African adult population.

METHODS

Twelve online focus groups were conducted across the following age groups: 18-34, 35-54, 55 + years old (total n = 70) in December 2021. Diversity across socioeconomic status, geographical areas, and urban and rural settings was maximised, with an equal representation of men and women. Focus groups were conducted, and audio recorded using an online platform, transcribed verbatim and thematically analysed using MAXQDA.

RESULTS

There were mixed perceptions around the pandemic, however, the majority of participants appreciated government actions at the onset of the pandemic and as a result government trust was reported to have initially been high. Nevertheless, as the pandemic progressed, challenges relating to government communication around the pandemic, the inconsistent application of preventative measures by government, the use of soldiers to enforce preventative measures, the banning of alcohol and cigarettes, government corruption and the pervasiveness of social media were reported to have eroded government trust, negatively impacting the uptake of preventative measures. Economic and psychological impacts were experienced differently across income groups. Low-income earners, who already had pre-existing economic challenges reported increased psychological and financial strain. While the once cushioned middle class reported an increase in job insecurity accompanied by psychological challenges. High income earners did not report economic challenges but reported being affected psychologically. Though, low-income earners reported an appreciation of the government financial relief afforded to them middle income earners appeared to not have received adequate financial support.

CONCLUSION

With the existing mistrust of government, there is need for government to leverage existing trusted sources in communities to aid in the implementation of preventative measures. These findings support the development of context specific solutions to address challenges faced at different socioeconomic levels.

Effectiveness of behavioural interventions to influence COVID-19 outcomes: A scoping review

Behavioural non-pharmaceutical interventions (NPIs) (e.g., mask wearing, quarantine, restriction on gatherings, physical distancing) have been used to interrupt transmission of COVID-19 and to reduce the impacts of the pandemic. The aim of this scoping review was to document the efficacy of behavioural NPIs to positively influence COVID-19 outcomes. Following PRISMA guidelines, a systematic search was conducted of PubMed, ScienceDirect, Psych INFO, Medline, CINAHL and Scopus for studies published between January 2020 and February 2023. Seventy -seven studies were eligible to be included in the review. Majority of the studies were conducted in high-income countries, with fewer studies in low- or middle-income countries. School closure, mask wearing, and non-essential business closure and shelter-in-place orders were the most prevalent NPIs investigated. School closure and mask wearing reported high effectiveness while shelter-in-place orders reported less effectiveness. Shelter-in-place orders when used in conjunction with other measures, did not enhance effectiveness. Public event bans, physical distancing, handwashing, and travel restrictions were largely effective, while the effectiveness of gathering restrictions depended on the limitation on numbers. Early implementation was associated with a higher effectiveness in reducing COVID-19 cases and deaths, the use of behavioural NPIs in combinations was reported to yield more effective results. Moreover, behavioural NPIs were reported to be dependent on their consistent use and were difficult behaviours to maintain, highlighting the need for behavioural change. This review highlighted the effectiveness of behavioural NPIs to positively influence COVID-19 reduction outcomes. Further research to promote country- and context-specific documents that will enhance the effectiveness of behavioural NPIs.

The Effects of COVID-19 Pandemic Lockdowns on Alcohol Consumption and Tobacco Smoking Behaviour in South Africa: A National Survey

INTRODUCTION

During the first phase of the coronavirus (COVID-19) pandemic lockdowns in South Africa (SA), both alcohol and tobacco were considered non-essential goods and their sales were initially prohibited and further restricted to certain days and timeframes. This study investigates self-reported changes in alcohol consumption and tobacco smoking behaviour in the general population during the COVID-19 pandemic lockdowns in SA.

METHODS

A cross-sectional national survey was conducted in October 2021 (before the Omicron wave 4 and while SA was in low-level lockdown) among 3,402 nationally representative respondents (weighted to 39,640,674) aged 18 years and older. Alcohol consumption and tobacco use were assessed from the beginning of the lockdown towards the end of March 2020 until October 2021 using the WHO-AUDIT and the US Centre for Disease Control (CDC) Global Adult Tobacco Survey questionnaires, respectively.

RESULTS

Among those that drank alcohol (33.2%), 31.4% were classified as having a drinking problem that could be hazardous or harmful and 18.9% had severe alcohol use disorder during the COVID-19 lockdowns. Twenty-two per cent (22.0%) of those that reported alcohol consumption reported that the COVID-19 pandemic lockdowns changed their alcohol consumption habits, with 38.1% reporting a decreased intake or quitting altogether. Among the one in five respondents (19.2%) who had ever smoked, most reported smoking at the time of the survey (82.6%) with many classified as light smokers (87.8%; ≤10 cigarettes/day). Almost a third (27.2%) of those smoking reported that the COVID-19 pandemic lockdowns had changed their use of tobacco products or vaping, with 60.0% reporting a reduction/quitting tobacco use. Given that sales were restricted this indicates that people could still get hold of tobacco products. Heavy smoking was associated with older age (p = 0.02), those classified as wealthy (p < 0.001), those who started or increased tobacco smoking during the pandemic lockdowns (p = 0.01) and residential provinces (p = 0.04).

CONCLUSION

Given restrictions on the sale of alcohol and tobacco in SA between 27 March and August 17, 2020, during the pandemic, respondents reported an overall decline in alcohol consumption and tobacco use which might suggest that the regulatory restrictive strategies on sales had some effect but may be inadequate, especially during times where individuals are likely to experience high-stress levels. These changes in alcohol consumption and tobacco use were different from what was reported in several European countries, possibly due to differences in the restrictions imposed in SA when compared to these European countries.

Growth patterns in childhood and adolescence and adult body composition: a pooled analysis of birth cohort studies from five low and middle-income countries (COHORTS collaboration)

OBJECTIVE

We examined associations among serial measures of linear growth and relative weight with adult body composition.

DESIGN

Secondary data analysis of prospective birth cohort studies.

SETTINGS

Six birth cohorts from Brazil, Guatemala, India, the Philippines and South Africa.

PARTICIPANTS

4173 individuals followed from birth to ages 22-46 years with complete and valid weight and height at birth, infancy, childhood and adolescence, and body composition in adult life.

EXPOSURES

Birth weight and conditional size (standardised residuals of height representing linear growth and of relative weight representing weight increments independent of linear size) in infancy, childhood and adolescence.

PRIMARY OUTCOME MEASURES

Body mass index, fat mass index (FMI), fat-free mass index (FFMI), fat mass/fat-free mass ratio (FM/FFM), and waist circumference in young and mid-adulthood.

RESULTS

In pooled analyses, a higher birth weight and relative weight gains in infancy, childhood and adolescence were positively associated with all adult outcomes. Relative weight gains in childhood and adolescence were the strongest predictors of adult body composition (β (95% CI) among men: FMI (childhood: 0.41 (0.26 to 0.55); adolescence: 0.39 (0.27 to 0.50)), FFMI (childhood: 0.50 (0.34 to 0.66); adolescence: 0.43 (0.32 to 0.55)), FM/FFM (childhood: 0.31 (0.16 to 0.47); adolescence: 0.31 (0.19 to 0.43))). Among women, similar patterns were observed, but, effect sizes in adolescence were slightly stronger than in childhood. Conditional height in infancy was positively associated with FMI (men: 0.08 (0.03 to 0.14); women: 0.11 (0.07 to 0.16)). Conditional height in childhood was positively but weakly associated with women's adiposity. Site-specific and sex-stratified analyses showed consistency in the direction of estimates, although there were differences in their magnitude.

CONCLUSIONS

Prenatal and postnatal relative weight gains were positive predictors of larger body size and increased adiposity in adulthood. A faster linear growth in infancy was a significant but weak predictor of higher adult adiposity.

Identifying the prevalence and correlates of multimorbidity in middle-aged men and women: a cross-sectional population-based study in four African countries

OBJECTIVES

To determine the prevalence of multimorbidity, to identify which chronic conditions cluster together and to identify factors associated with a greater risk for multimorbidity in sub-Saharan Africa (SSA).

DESIGN

Cross-sectional, multicentre, population-based study.

SETTING

Six urban and rural communities in four sub-Saharan African countries.

PARTICIPANTS

Men (n=4808) and women (n=5892) between the ages of 40 and 60 years from the AWI-Gen study.

MEASURES

Sociodemographic and anthropometric data, and multimorbidity as defined by the presence of two or more of the following conditions: HIV infection, cardiovascular disease, chronic kidney disease, asthma, diabetes, dyslipidaemia, hypertension.

RESULTS

Multimorbidity prevalence was higher in women compared with men (47.2% vs 35%), and higher in South African men and women compared with their East and West African counterparts. The most common disease combination at all sites was dyslipidaemia and hypertension, with this combination being more prevalent in South African women than any single disease (25% vs 21.6%). Age and body mass index were associated with a higher risk of multimorbidity in men and women; however, lifestyle correlates such as smoking and physical activity were different between the sexes.

CONCLUSIONS

The high prevalence of multimorbidity in middle-aged adults in SSA is of concern, with women currently at higher risk. This prevalence is expected to increase in men, as well as in the East and West African region with the ongoing epidemiological transition. Identifying common disease clusters and correlates of multimorbidity is critical to providing effective interventions.

Development, Implementation, and Process Evaluation of Bukhali: An Intervention from Preconception to Early Childhood

The Healthy Life Trajectories Initiative, an international consortium developed in partnership with the World Health Organization, is addressing childhood obesity from a life-course perspective. It hypothesises that an integrated complex intervention from preconception, through pregnancy, infancy and early childhood, will reduce childhood adiposity and non-communicable disease risk, and improve child development. As part of the Healthy Life Trajectories Initiative in South Africa, the Bukhali randomised controlled trial is being conducted with 18–28-year-old women in Soweto, where young women face numerous challenges to their physical and mental health. The aims of this paper were to describe the intervention development process (including adaptations), intervention components, and process evaluation; and to highlight key lessons learned. Intervention materials have been developed according to the life-course stages: preconception (Bukhali), pregnancy (Bukhali Baby), infancy (Bukhali Nana; birth—2 years), and early childhood (Bukhali Mntwana, 2–5 years). The intervention is delivered by community health workers, and includes the provision of health literacy resources, multi-micronutrient supplementation, in-person health screening, services and referral, nutrition risk support, SMS-reminders and telephonic contacts to assist with behaviour change goals. A key adaption is the incorporation of principles of trauma-information care, given the mental health challenges faced by participants. The Bukhali process evaluation is focussing on context, implementation and mechanisms of impact, using a mixed methods approach. Although the completion of the trial is still a number of years away, the documentation of the intervention development process and process evaluation of the trial can provide lessons for the development, implementation, and evaluation of such complex life-course trials.

Machine learning for accurate estimation of fetal gestational age based on ultrasound images

Accurate estimation of gestational age is an essential component of good obstetric care and informs clinical decision-making throughout pregnancy. As the date of the last menstrual period is often unknown or uncertain, ultrasound measurement of fetal size is currently the best method for estimating gestational age. The calculation assumes an average fetal size at each gestational age. The method is accurate in the first trimester, but less so in the second and third trimesters as growth deviates from the average and variation in fetal size increases. Consequently, fetal ultrasound late in pregnancy has a wide margin of error of at least ±2 weeks' gestation. Here, we utilise state-of-the-art machine learning methods to estimate gestational age using only image analysis of standard ultrasound planes, without any measurement information. The machine learning model is based on ultrasound images from two independent datasets: one for training and internal validation, and another for external validation. During validation, the model was blinded to the ground truth of gestational age (based on a reliable last menstrual period date and confirmatory first-trimester fetal crown rump length). We show that this approach compensates for increases in size variation and is even accurate in cases of intrauterine growth restriction. Our best machine-learning based model estimates gestational age with a mean absolute error of 3.0 (95% CI, 2.9-3.2) and 4.3 (95% CI, 4.1-4.5) days in the second and third trimesters, respectively, which outperforms current ultrasound-based clinical biometry at these gestational ages. Our method for dating the pregnancy in the second and third trimesters is, therefore, more accurate than published methods.

Protocol for the PLAY Study: a randomised controlled trial of an intervention to improve infant development by encouraging maternal self-efficacy using behavioural feedback

INTRODUCTION

The early infant caregiving environment is crucial in the formation of parent-child relationships, neurobehavioural development and thus child outcomes. This protocol describes the Play Love And You (PLAY) Study, a phase 1 trial of an intervention designed to promote infant development through encouraging maternal self-efficacy using behavioural feedback, and supportive interventions.

METHODS AND ANALYSIS

210 mother-infant pairs will be recruited at delivery from community clinics in Soweto, South Africa, and individually randomised (1:1) into two groups. The trial will consist of a standard of care arm and an intervention arm. The intervention will start at birth and end at 12 months, and outcome assessments will be made when the infants are 0, 6 and 12 months of age. The intervention will be delivered by community health helpers using an app with resource material, telephone calls, in person visits and behavioural feedback with individualised support. Every 4 months, mothers in the intervention group will receive rapid feedback via the app and in person on their infant's movement behaviours and on their interaction styles with their infant. At recruitment, and again at 4 months, mothers will be screened for mental health risk and women who score in the high-risk category will receive an individual counselling session from a licensed psychologist, followed by referral and continued support as necessary. The primary outcome is efficacy of the intervention in improving maternal self-efficacy, and the secondary outcomes are infant development at 12 months, and feasibility and acceptability of each component of the intervention.

ETHICS AND DISSEMINATION

The PLAY Study has received ethical approval from the Human Research Ethics Committee of the University of the Witwatersrand (M220217). Participants will be provided with an information sheet and required to provide written consent prior to being enrolled. Study results will be shared via publication in peer-reviewed journals, conference presentation and media engagement.

TRIAL REGISTRATION NUMBER

This trial was registered with the Pan African Clinical Trials Registry (https://pactr.samrc.ac.za) on 10 February 2022 (identifier: PACTR202202747620052).

Physical Activity and Its Association With Body Mass Index: A Cross-Sectional Analysis in Middle-Aged Adults From 4 Sub-Saharan African Countries

BACKGROUND

This study aimed to explore association of self-reported physical activity domains of work, leisure, and transport-related physical activity and body mass index (BMI) in 9388 adult men and women from the Africa-Wits-INDEPTH partnership for Genomic (AWI-Gen) study in Africa. Africa-Wits-INDEPTH partnership for Genomic is a large, population-based cross-sectional cohort with participants from 6 sites from rural and urban areas in 4 sub-Saharan African countries.

METHODS

A sex-stratified meta-analysis of cross-sectional data from men and women aged 29-82 years was used to assess the association of physical activity with BMI.

RESULTS

Overall, meeting physical activity guidelines of at least 150 minutes per week was associated with 0.82 kg/m2 lower BMI in men (β = -0.80 kg/m2; 95% confidence interval [CI], -1.14 to -0.47) and 0.68 kg/m2 lower BMI in women (β = -0.68 kg/m2; 95% CI, -1.03 to -0.33). Sex and site-specific differences were observed in the associations between physical activity domains and BMI. Among those who met physical activity guidelines, there was an inverse association between transport-related physical activity and BMI in men from Nanoro (Burkina Faso) (β = -0.79 kg/m2; 95% CI, -1.25 to -0.33) as well as work-related physical activity and BMI in Navrongo men (Ghana) (β = -0.76 kg/m2; 95% CI, -1.25 to -0.27) and Nanoro women (β = -0.90 kg/m2; 95% CI, -1.44 to -0.36).

CONCLUSIONS

Physical activity may be an effective strategy to curb rising obesity in Africa. More studies are needed to assess the impact of sex and geographic location-specific physical activity interventions on obesity.

An intergenerational life-course approach to address early childhood obesity and adiposity: the Healthy Life Trajectories Initiative (HeLTI)

BACKGROUND

Interactions between genes and early-life exposures during conception, fetal life, infancy, and early childhood have been shown to affect an individual's health later in life. Maternal undernutrition and obesity, gestational diabetes, and impaired growth in utero and in early life are associated with adiposity and overweight and obesity in childhood, which are risk factors for poor health trajectories and non-communicable diseases. In Canada, China, India, and South Africa, 10-30% of children aged 5-16 years are overweight or obese.

METHODS

The application of developmental origins of health and disease principles offers a novel approach to prevention of overweight and obesity and reduction of adiposity by delivering integrated interventions across the life course, starting before conception and continuing through early childhood. The Healthy Life Trajectories Initiative (HeLTI) was established in 2017 through a unique collaboration between national funding agencies in Canada, China, India, South Africa, and WHO. The aim of HeLTI is to evaluate the effect of an integrated four-phase intervention starting preconceptionally and continuing through pregnancy, infancy, and early childhood on reducing childhood adiposity (fat mass index) and overweight and obesity, and optimising early child development, nutrition, and other healthy behaviours.

FINDINGS

Approximately 22 000 women are being recruited in Shanghai (China), Mysore (India), Soweto (South Africa), and across various provinces of Canada. Women who conceive (an expected 10 000) and their children will be followed up until the child reaches the age of 5 years.

INTERPRETATION

HeLTI has harmonised the intervention, measures, tools, biospecimen collection, and analysis plans for the trial to be run across four countries. HeLTI will help establish whether an intervention aimed at addressing maternal health behaviours, nutrition, and weight; providing psychosocial support to reduce maternal stress and prevent mental illness; optimising infant nutrition, physical activity, and sleep; and promoting parenting skills can reduce the intergenerational risk of excess childhood adiposity and overweight and obesity across diverse settings.

FUNDING

Canadian Institutes of Health Research; National Science Foundation of China; Department of Biotechnology, India; and South African Medical Research Council.

Maternal Education Potentially Moderates the MAOA uVNTR Effects on Externalizing Behavior in Black South African Children

Interactions between the MAOA uVNTR and rearing environment are suggested to influence the developmental manifestations of childhood internalizing and externalizing behavior. However, few studies in the MAOA literature have included continental African children, or focused on non-clinical samples. We explored the main and interactive effects of the MAOA uVNTR (high and low activity alleles) in Black South African male (n = 478) and female (n = 540) children who were part of the longitudinal Birth to Twenty Plus cohort. Historical data on birth weight, gestational age at delivery, socioeconomic status, and maternal education were combined with genotypic information and analyzed using regression modeling. We found no significant main effects for the MAOA uVNTR on childhood behavior in either sex. A significant interaction (p = .04) was identified between MAOA and maternal education, suggesting that externalizing behavior in boys carrying a low activity MAOA allele varied in direct proportion to the education levels of their mothers. However, the model fit failed to reach significance, possibly due to our inclusion of only non-clinical pre-pubertal males. No significant interactions were detected for female children. Our findings lend tentative credibility to the Environmental Sensitivity metaframework, which suggests that MAOA is an important plasticity factor in childhood development.

Nutrient Patterns and Body Mass Index: A Comparative Longitudinal Analysis in Urban Black South African Adolescents and Adults

OBJECTIVE

We set out to evaluate the association between nutrient patterns and general adiposity in black South African adolescents and adults and to determine whether the interactions are longitudinally sustained over 24 months.

METHODS

Principal Component Analysis (PCA) was used to derive the nutrient patterns of 750 participants (250 adolescents between 13 and 17 years old and 500 adults who were 27 years or 45⁺ years old). PCA was applied to 25 nutrients, computed from the quantified food frequency questionnaire (QFFQ) over a 24 months period.

RESULTS

The nutrient patterns between adolescents and adults were similar over time; however, their associations with BMI were different. Among the adolescents, only the "plant-driven nutrients pattern" was significantly associated with a 0.56% (95% CI (0.33; 0.78); p < 0.001) increase in BMI. Among the adults, the "plant-driven nutrient pattern" (0.43% (95% CI (0.03; 0.85); p < 0.001) and the "fat-driven nutrients pattern" (0.18% (95% CI (0.06; 0.29); p < 0.001) were significantly associated with a BMI increase. Furthermore, the "plant-driven nutrient pattern", "fat-driven nutrient pattern" and the animal-driven nutrient pattern revealed sex differences in their association with BMI.

CONCLUSION

Urban adolescents and adults had consistent nutrient patterns, but their BMI relationships changed with age and gender, an important finding for future nutrition interventions.

Drivers of disparities in stage at diagnosis among women with breast cancer: South African breast cancers and HIV outcomes cohort

OBJECTIVE

In low- and middle-income countries (LMICs), advanced-stage diagnosis of breast cancer (BC) is common, and this contributes to poor survival. Understanding the determinants of the stage at diagnosis will aid in designing interventions to downstage disease and improve survival from BC in LMICs.

METHODS

Within the South African Breast Cancers and HIV Outcomes (SABCHO) cohort, we examined factors affecting the stage at diagnosis of histologically confirmed invasive breast cancer at five tertiary hospitals in South Africa (SA). The stage was assessed clinically. To examine the associations of the modifiable health system, socio-economic/household and non-modifiable individual factors, hierarchical multivariable logistic regression with odds of late-stage at diagnosis (stage III-IV), was used.

RESULTS

The majority (59%) of the included 3497 women were diagnosed with late-stage BC disease. The effect of health system-level factors on late-stage BC diagnosis was consistent and significant even when adjusted for both socio-economic- and individual-level factors. Women diagnosed in a tertiary hospital that predominantly serves a rural population were 3 times (OR = 2.89 (95% CI: 1.40-5.97) as likely to be associated with late-stage BC diagnosis when compared to those diagnosed at a hospital that predominantly serves an urban population. Taking more than 3 months from identifying the BC problem to the first health system entry (OR = 1.66 (95% CI: 1.38-2.00)), and having luminal B (OR = 1.49 (95% CI: 1.19-1.87)) or HER2-enriched (OR = 1.64 (95% CI: 1.16-2.32)) molecular subtype as compared to luminal A, were associated with a late-stage diagnosis. Whilst having a higher socio-economic level (a wealth index of 5) reduced the probability of late-stage BC at diagnosis, (OR = 0.64 (95% CI: 0.47-0.85)).

CONCLUSION

Advanced-stage diagnosis of BC among women in SA who access health services through the public health system was associated with both modifiable health system-level factors and non-modifiable individual-level factors. These may be considered as elements in interventions to reduce the time to diagnosis of breast cancer in women.

Food insecurity and coping strategies and their association with anxiety and depression: a nationally representative South African survey

OBJECTIVE

To investigate food insecurity and related coping strategies among South African households and their associations with anxiety and depression.

DESIGN

Cross-sectional study. Food insecurity and coping strategies were assessed using a modified Community Childhood Hunger Identification Project and the Coping Strategies Index questionnaires. The Generalized Anxiety Disorder-7 and Patient Health Questionnaire-9 were used to assess anxiety and depression risk. Ordered logistic regressions were used to test associations of food insecurity and related coping strategies with anxiety and depression.

SETTING

South Africa during COVID-19, October 2021.

PARTICIPANTS

Nationally representative sample of 3402 adults, weighted to 39,640,674 South African households.

RESULTS

About 20·4 % of South African households were food insecure, with the most affected being from the lowest socio-economic groups. Shifting from 'food secure' to 'at risk' or from 'at risk' to 'food insecure' group was associated with 1·7 times greater odds of being in a higher category of anxiety or depression (P < 0·001). All coping strategies were used to some extent in South African households, with 46·0 % relying on less preferred and less expensive foods and 20·9 % sending a household member to beg for food. These coping strategies were mostly used by food-insecure households. Although the odds of moving to a higher category of anxiety and depression were observed among all coping strategies (all P < 0·001), begging for food was associated with the highest odds (OR = 2·3).

CONCLUSIONS

Food insecurity remains a major health threat in South Africa. Public measures to address mental health should consider reductions in food insecurity as part of their strategy.

Multimorbidity and overall survival among women with breast cancer: results from the South African Breast Cancer and HIV Outcomes Study

BACKGROUND

Breast cancer survival in South Africa is low, but when diagnosed with breast cancer, many women in South Africa also have other chronic conditions. We investigated the impact of multimorbidity (≥ 2 other chronic conditions) on overall survival among women with breast cancer in South Africa.

METHODS

Between 1 July 2015 and 31 December 2019, we enrolled women newly diagnosed with breast cancer at six public hospitals participating in the South African Breast Cancer and HIV Outcomes (SABCHO) Study. We examined seven chronic conditions (obesity, hypertension, diabetes, HIV, cerebrovascular diseases (CVD), asthma/chronic obstructive pulmonary disease, and tuberculosis), and we compared socio-demographic, clinical, and treatment factors between patients with and without each condition, and with and without multimorbidity. We investigated the association of multimorbidity with overall survival using multivariable Cox proportional hazard models.

RESULTS

Of 3,261 women included in the analysis, 45% had multimorbidity; obesity (53%), hypertension (41%), HIV (22%), and diabetes (13%) were the most common individual conditions. Women with multimorbidity had poorer overall survival at 3 years than women without multimorbidity in both the full cohort (60.8% vs. 64.3%, p = 0.036) and stage groups: stages I-II, 80.7% vs. 86.3% (p = 0.005), and stage III, 53.0% vs. 59.4% (p = 0.024). In an adjusted model, women with diabetes (hazard ratio (HR) = 1.20, 95% confidence interval (CI) = 1.03-1.41), CVD (HR = 1.43, 95% CI = 1.17-1.76), HIV (HR = 1.21, 95% CI = 1.06-1.38), obesity + HIV (HR = 1.24 95% CI = 1.04-1.48), and multimorbidity (HR = 1.26, 95% CI = 1.13-1.40) had poorer overall survival than women without these conditions.

CONCLUSIONS

Irrespective of the stage, multimorbidity at breast cancer diagnosis was an important prognostic factor for survival in our SABCHO cohort. The high prevalence of multimorbidity in our cohort calls for more comprehensive care to improve outcomes for South African women with breast cancer.