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1.
Maturitas ; 187: 108069, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39032388

RESUMO

BACKGROUND: Menopause and HIV are associated with cardiometabolic disease. In sub-Saharan Africa there is a growing population of midlife women living with HIV and a high prevalence of cardiometabolic disease. OBJECTIVES: The aim of this study was to determine whether menopause and HIV were associated with cardiometabolic disease risk factors in a population of midlife sub-Saharan African women. STUDY DESIGN: This was a cross-sectional comparison of cardiometabolic disease risk factors between 944 premenopausal women (733 living without HIV and 211 living with HIV) and 1135 postmenopausal women (932 living without HIV and 203 living with HIV) in sub-Saharan Africa. MAIN OUTCOME MEASURES: Anthropometric and cardiometabolic variables were compared between pre- and postmenopausal women living without HIV and between pre- and postmenopausal women living with HIV and between women living without HIV and women living with HIV. RESULTS: The prevalence of HIV was 19.9 %. Age at menopause was lower in women living with HIV than in women living without HIV (48.1 ± 5.1 vs 50.9 ± 4.7 years, p < 0.001). Women living with HIV and receiving efavirenz-based antiretroviral therapy had a lower body mass index (BMI), hip circumference, blood pressure and carotid intima media thickness but higher triglyceride levels and insulin resistance than women living without HIV. Antiretroviral therapy-naïve women living with HIV had lower HDL-cholesterol than women living without HIV. In this study, menopause was associated with higher LDL-C levels, regardless of HIV status. CONCLUSION: The high prevalence of obesity and related cardiometabolic disease risk factors in these midlife sub-Saharan African women is not related to the menopausal transition. The association of cardiometabolic disease risk factors with HIV and antiretroviral therapy is complex and requires further investigation in longitudinal studies, as does the negative association of age at final menstrual period with HIV.

2.
J Endocr Soc ; 8(8): bvae129, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-39055720

RESUMO

Objectives: To investigate longitudinal changes in SHBG and free testosterone (free T) levels among Black middle-aged African men, with and without coexistent HIV, and explore associations with incident dysglycaemia and measures of glucose metabolism. Design: This longitudinal study enrolled 407 Black South African middle-aged men, comprising primarily 322 men living without HIV (MLWOH) and 85 men living with HIV (MLWH), with normal fasting glucose at enrollment. Follow-up assessments were conducted after 3.1 ± 1.5 years. Methods: At baseline and follow-up, SHBG, albumin, and total testosterone were measured and free T was calculated. An oral glucose tolerance test at follow-up determined dysglycaemia (impaired fasting glucose, impaired glucose tolerance, type 2 diabetes) and glucose metabolism parameters including insulin sensitivity (Matsuda index), insulin resistance (homeostasis model assessment of insulin resistance), and beta(ß)-cell function (disposition index). The primary analysis focussed on MLWOH, with a subanalysis on MLWH to explore whether associations in MLWOH differed from MLWH. Results: The prevalence of dysglycaemia at follow-up was 17% (n = 55) in MLWOH. Higher baseline SHBG was associated with a lower risk of incident dysglycaemia (odds ratio 0.966; 95% confidence interval 0.945-0.987) and positively associated with insulin sensitivity (ß = 0.124, P < .001) and ß-cell function (ß = 0.194, P = .001) at follow-up. Free T did not predict dysglycaemia. In MLWH, dysglycaemia prevalence at follow-up was 12% (n = 10). Neither baseline SHBG nor free T were associated with incident dysglycaemia and glucose metabolism parameters in MLWH. Conclusion: SHBG levels predict the development of dysglycaemia in middle-aged African men but do not exhibit the same predictive value in MLWH.

3.
Artigo em Inglês | MEDLINE | ID: mdl-38950129

RESUMO

OBJECTIVE: To explore depot-specific functional aspects of adipose tissue, examining the putative role for menopause and HIV status on insulin sensitivity (SI) and beta-cell function in Black South African women. METHODS: Women (n = 92) from the Middle-Aged Soweto Cohort, including premenopausal HIV-negative (n = 21); premenopausal women living with HIV (WLWH; n = 11); postmenopausal HIV-negative (n = 42); postmenopausal WLWH (n = 18) underwent the following tests: body composition (dual energy x-ray absorptiometry); fasting bloods for sex hormones, inflammation and adipokines; frequently sampled intravenous glucose tolerance test for SI and beta-cell function (disposition index, DI); abdominal (aSAT) and gluteal subcutaneous adipose tissue (gSAT) biopsies for cell size and mRNA expression of adipokines, inflammation, and estrogen receptors [ER]. RESULTS: Depot-specific associations between gene expression and insulin parameters did not differ by HIV or menopause status. Pooled analysis showed significant models for SI (P = 0.002) and DI (P = 0.003). Higher SI was associated with lower leptin and CD11c expression in aSAT and higher adiponectin in gSAT. Higher DI was associated with higher aSAT and gSAT expression of adiponectin, LPL, ERα, and PPARγ, and lower leptin in aSAT. WLWH had higher expression of adiponectin and lower expression of leptin in both aSAT (P = 0.002 and P = 0.005) and gSAT (P = 0.004 and P = 0.002), respectively, and a larger proportion of smaller cells in aSAT (P < 0.001). CONCLUSION: Insulin sensitivity and beta cell function were distinctively associated with aSAT and gSAT. While menopause did not influence these relationships, HIV had a significant effect on adipose tissue, characterised by variations in cell size distribution and transcript levels within the depots.

4.
Front Genet ; 15: 1372042, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38812969

RESUMO

Background: Genome-wide association studies (GWAS) have predominantly focused on populations of European and Asian ancestry, limiting our understanding of genetic factors influencing kidney disease in Sub-Saharan African (SSA) populations. This study presents the largest GWAS for urinary albumin-to-creatinine ratio (UACR) in SSA individuals, including 8,970 participants living in different African regions and an additional 9,705 non-resident individuals of African ancestry from the UK Biobank and African American cohorts. Methods: Urine biomarkers and genotype data were obtained from two SSA cohorts (AWI-Gen and ARK), and two non-resident African-ancestry studies (UK Biobank and CKD-Gen Consortium). Association testing and meta-analyses were conducted, with subsequent fine-mapping, conditional analyses, and replication studies. Polygenic scores (PGS) were assessed for transferability across populations. Results: Two genome-wide significant (P < 5 × 10-8) UACR-associated loci were identified, one in the BMP6 region on chromosome 6, in the meta-analysis of resident African individuals, and another in the HBB region on chromosome 11 in the meta-analysis of non-resident SSA individuals, as well as the combined meta-analysis of all studies. Replication of previous significant results confirmed associations in known UACR-associated regions, including THB53, GATM, and ARL15. PGS estimated using previous studies from European ancestry, African ancestry, and multi-ancestry cohorts exhibited limited transferability of PGS across populations, with less than 1% of observed variance explained. Conclusion: This study contributes novel insights into the genetic architecture of kidney disease in SSA populations, emphasizing the need for conducting genetic research in diverse cohorts. The identified loci provide a foundation for future investigations into the genetic susceptibility to chronic kidney disease in underrepresented African populations Additionally, there is a need to develop integrated scores using multi-omics data and risk factors specific to the African context to improve the accuracy of predicting disease outcomes.

5.
Genome Med ; 16(1): 74, 2024 05 30.
Artigo em Inglês | MEDLINE | ID: mdl-38816834

RESUMO

BACKGROUND: Polygenic prediction studies in continental Africans are scarce. Africa's genetic and environmental diversity pose a challenge that limits the generalizability of polygenic risk scores (PRS) for body mass index (BMI) within the continent. Studies to understand the factors that affect PRS variability within Africa are required. METHODS: Using the first multi-ancestry genome-wide association study (GWAS) meta-analysis for BMI involving continental Africans, we derived a multi-ancestry PRS and compared its performance to a European ancestry-specific PRS in continental Africans (AWI-Gen study) and a European cohort (Estonian Biobank). We then evaluated the factors affecting the performance of the PRS in Africans which included fine-mapping resolution, allele frequencies, linkage disequilibrium patterns, and PRS-environment interactions. RESULTS: Polygenic prediction of BMI in continental Africans is poor compared to that in European ancestry individuals. However, we show that the multi-ancestry PRS is more predictive than the European ancestry-specific PRS due to its improved fine-mapping resolution. We noted regional variation in polygenic prediction across Africa's East, South, and West regions, which was driven by a complex interplay of the PRS with environmental factors, such as physical activity, smoking, alcohol intake, and socioeconomic status. CONCLUSIONS: Our findings highlight the role of gene-environment interactions in PRS prediction variability in Africa. PRS methods that correct for these interactions, coupled with the increased representation of Africans in GWAS, may improve PRS prediction in Africa.


Assuntos
População Negra , Índice de Massa Corporal , Estudo de Associação Genômica Ampla , Herança Multifatorial , Humanos , África , População Negra/genética , Polimorfismo de Nucleotídeo Único , População Branca/genética , Predisposição Genética para Doença , Frequência do Gene , Interação Gene-Ambiente , Desequilíbrio de Ligação , Masculino , Feminino
6.
Glob Health Action ; 17(1): 2325726, 2024 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-38577879

RESUMO

Increasing evidence suggests that urban health objectives are best achieved through a multisectoral approach. This approach requires multiple sectors to consider health and well-being as a central aspect of their policy development and implementation, recognising that numerous determinants of health lie outside (or beyond the confines of) the health sector. However, collaboration across sectors remains scarce and multisectoral interventions to support health are lacking in Africa. To address this gap in research, we conducted a mixed-method systematic review of multisectoral interventions aimed at enhancing health, with a particular focus on non-communicable diseases in urban African settings. Africa is the world's fastest urbanising region, making it a critical context in which to examine the impact of multisectoral approaches to improve health. This systematic review provides a valuable overview of current knowledge on multisectoral urban health interventions and enables the identification of existing knowledge gaps, and consequently, avenues for future research. We searched four academic databases (PubMed, Scopus, Web of Science, Global Health) for evidence dated 1989-2019 and identified grey literature from expert input. We identified 53 articles (17 quantitative, 20 qualitative, 12 mixed methods) involving collaborations across 22 sectors and 16 African countries. The principle guiding the majority of the multisectoral interventions was community health equity (39.6%), followed by healthy cities and healthy urban governance principles (32.1%). Targeted health outcomes were diverse, spanning behaviour, environmental and active participation from communities. With only 2% of all studies focusing on health equity as an outcome and with 47% of studies published by first authors located outside Africa, this review underlines the need for future research to prioritise equity both in terms of research outcomes and processes. A synthesised framework of seven interconnected components showcases an ecosystem on multisectoral interventions for urban health that can be examined in the future research in African urban settings that can benefit the health of people and the planet.Paper ContextMain findings: Multisectoral interventions were identified in 27.8% of African countries in the African Union, targeted at major cities with five sectors present at all intervention stages: academia or research, agriculture, government, health, and non-governmental.Added knowledge: We propose a synthesised framework showcasing an ecosystem on multisectoral interventions for urban health that can guide future research in African urban settings.Global health impact for policy and action: This study reveals a crucial gap in evidence on evaluating the long-term impact of multisectoral interventions and calls for partnerships involving various sectors and robust community engagement to effectively deliver and sustain health-promoting policies and actions.


Assuntos
Saúde da População Urbana , Humanos , África , Cidades , Política de Saúde
7.
bioRxiv ; 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38559015

RESUMO

Population studies are crucial in understanding the complex interplay between the gut microbiome and geographical, lifestyle, genetic, and environmental factors. However, populations from low- and middle-income countries, which represent ~84% of the world population, have been excluded from large-scale gut microbiome research. Here, we present the AWI-Gen 2 Microbiome Project, a cross-sectional gut microbiome study sampling 1,803 women from Burkina Faso, Ghana, Kenya, and South Africa. By intensively engaging with communities that range from rural and horticultural to urban informal settlements and post-industrial, we capture population diversity that represents a far greater breadth of the world's population. Using shotgun metagenomic sequencing, we find that study site explains substantially more microbial variation than disease status. We identify taxa with strong geographic and lifestyle associations, including loss of Treponema and Cryptobacteroides species and gain of Bifidobacterium species in urban populations. We uncover a wealth of prokaryotic and viral novelty, including 1,005 new bacterial metagenome-assembled genomes, and identify phylogeography signatures in Treponema succinifaciens. Finally, we find a microbiome signature of HIV infection that is defined by several taxa not previously associated with HIV, including Dysosmobacter welbionis and Enterocloster sp. This study represents the largest population-representative survey of gut metagenomes of African individuals to date, and paired with extensive clinical biomarkers, demographic data, and lifestyle information, provides extensive opportunity for microbiome-related discovery and research.

8.
BMJ Paediatr Open ; 8(1)2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38599800

RESUMO

OBJECTIVE: To determine whether weekly oral vitamin D supplementation influences growth, body composition, pubertal development or spirometric outcomes in South African schoolchildren. DESIGN: Phase 3 double-blind randomised placebo-controlled trial. SETTING: Socioeconomically disadvantaged peri-urban district of Cape Town, South Africa. PARTICIPANTS: 1682 children of black African ancestry attending government primary schools and aged 6-11 years at baseline. INTERVENTIONS: Oral vitamin D3 (10 000 IU/week) versus placebo for 3 years. MAIN OUTCOME MEASURES: Height-for-age and body mass index-for-age, measured in all participants; Tanner scores for pubertal development, spirometric lung volumes and body composition, measured in a subset of 450 children who additionally took part in a nested substudy. RESULTS: Mean serum 25-hydroxyvitamin D3 concentration at 3-year follow-up was higher among children randomised to receive vitamin D versus placebo (104.3 vs 64.7 nmol/L, respectively; mean difference (MD) 39.7 nmol/L, 95% CI 37.6 to 41.9 nmol/L). No statistically significant differences in height-for-age z-score (adjusted MD (aMD) -0.08, 95% CI -0.19 to 0.03) or body mass index-for-age z-score (aMD -0.04, 95% CI -0.16 to 0.07) were seen between vitamin D versus placebo groups at follow-up. Among substudy participants, allocation to vitamin D versus placebo did not influence pubertal development scores, % predicted forced expiratory volume in 1 s (FEV1), % predicted forced vital capacity (FVC), % predicted FEV1/FVC, fat mass or fat-free mass. CONCLUSIONS: Weekly oral administration of 10 000 IU vitamin D3 boosted vitamin D status but did not influence growth, body composition, pubertal development or spirometric outcomes in South African schoolchildren. TRIAL REGISTRATION NUMBERS: ClinicalTrials.gov NCT02880982, South African National Clinical Trials Register DOH-27-0916-5527.


Assuntos
Colestanos , Deficiência de Vitamina D , Criança , Humanos , Composição Corporal , Colecalciferol/uso terapêutico , Colestanos/uso terapêutico , Suplementos Nutricionais , África do Sul/epidemiologia , Espirometria , Vitamina D/uso terapêutico , Deficiência de Vitamina D/tratamento farmacológico , Vitaminas/uso terapêutico , Método Duplo-Cego
10.
J Bone Miner Res ; 39(3): 211-221, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38477739

RESUMO

Randomized controlled trials (RCTs) to determine the influence of vitamin D on BMC and fracture risk in children of Black African ancestry are lacking. We conducted a sub-study (n = 450) nested within a phase 3 RCT of weekly oral supplementation with 10 000 IU vitamin D3 vs placebo for 3 yr in HIV-uninfected Cape Town schoolchildren aged 6-11 yr. Outcomes were BMC at the whole body less head (WBLH) and LS and serum 25-hydroxyvitamin D3 (25(OH)D3), PTH, alkaline phosphatase, C-terminal telopeptide, and PINP. Incidence of fractures was a secondary outcome of the main trial (n = 1682). At baseline, mean serum 25(OH)D3 concentration was 70.0 nmol/L (SD 13.5), and 5.8% of participants had serum 25(OH)D3 concentrations <50 nmol/L. Among sub-study participants, end-trial serum 25(OH)D3 concentrations were higher for participants allocated to vitamin D vs placebo (adjusted mean difference [aMD] 39.9 nmol/L, 95% CI, 36.1 to 43.6) and serum PTH concentrations were lower (aMD -0.55 pmol/L, 95% CI, -0.94 to -0.17). However, no interarm differences were seen for WBLH BMC (aMD -8.0 g, 95% CI, -30.7 to 14.7) or LS BMC (aMD -0.3 g, 95% CI, -1.3 to 0.8) or serum concentrations of bone turnover markers. Fractures were rare among participants in the main trial randomized to vitamin D vs placebo (7/755 vs 10/758 attending at least 1 follow-up; adjusted odds ratio 0.70, 95% CI, 0.27 to 1.85). In conclusion, a 3-yr course of weekly oral vitamin D supplementation elevated serum 25(OH)D3 concentrations and suppressed serum PTH concentrations in HIV-uninfected South African schoolchildren of Black African ancestry but did not influence BMC or serum concentrations of bone turnover markers. Fracture incidence was low, limiting power to detect an effect of vitamin D on this outcome.


Vitamin D­the "sunshine vitamin"­is essential for helping the body to absorb calcium from the diet, which is laid down in bone to improve its strength. There is a lack of clinical trials testing whether vitamin D supplements can improve bone content of calcium and other minerals, or reduce risk of bone fractures (broken bones) in children of Black African ancestry. We therefore conducted such a study, recruiting 1682 schoolchildren aged 6­11 yr living in Cape Town, South Africa. We found that a weekly dose of 10 000 international units (250 micrograms) of vitamin D3, given by mouth for 3 yr, was effective in boosting vitamin D levels in trial participants who received it. However, this did not have any effect on bone content of calcium and other minerals. Relatively few children experienced a broken bone during the study, so we were unable to say with confidence whether or not vitamin D supplements might affect this outcome.


Assuntos
Fraturas Ósseas , Infecções por HIV , Deficiência de Vitamina D , Criança , Humanos , Densidade Óssea , Remodelação Óssea , Calcifediol/farmacologia , Colecalciferol/uso terapêutico , Suplementos Nutricionais , Método Duplo-Cego , Fraturas Ósseas/tratamento farmacológico , Fraturas Ósseas/epidemiologia , Fraturas Ósseas/prevenção & controle , Infecções por HIV/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como Assunto , África do Sul/epidemiologia , Vitamina D , Deficiência de Vitamina D/tratamento farmacológico , População Negra , População da África Austral
11.
BMJ Open ; 14(3): e065498, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38458795

RESUMO

OBJECTIVES: Given the increasing prevalence of obesity and need for effective interventions, there is a growing interest in understanding how an individual's body image can inform obesity prevention and management. This study's objective was to examine the use of silhouette showcards to measure body size perception compared with measured body mass index, and assess body size dissatisfaction, in three different African-origin populations spanning the epidemiological transition. An ancillary objective was to investigate associations between body size perception and dissatisfaction with diabetes and hypertension. SETTING: Research visits were completed in local research clinics in respective countries. PARTICIPANTS: Seven hundred and fifty-one African-origin participants from the USA and the Republic of Seychelles (both high-income countries), and Ghana (low/middle-income country). PRIMARY AND SECONDARY OUTCOME MEASURES: Silhouette showcards were used to measure perceived body size and body size dissatisfaction. Objectively measured body size was measured using a scale and stadiometer. Diabetes was defined as fasting blood glucose ≥126 mg/dL and hypertension was defined as ≥130 mm Hg/80 mm Hg. RESULTS: Most women and men from the USA and Seychelles had 'Perceived minus Actual weight status Discrepancy' scores less than 0, meaning they underestimated their actual body size. Similarly, most overweight or obese men and women also underestimated their body size, while normal weight men and women were accurately able to estimate their body size. Finally, participants with diabetes were able to accurately estimate their body size and similarly desired a smaller body size. CONCLUSIONS: This study highlights that overweight and obese women and men from countries spanning the epidemiological transition were unable to accurately perceive their actual body size. Understanding people's perception of their body size is critical to implementing successful obesity prevention programmes across the epidemiological transition.


Assuntos
Diabetes Mellitus , Hipertensão , Masculino , Humanos , Feminino , Sobrepeso/epidemiologia , Sobrepeso/complicações , Imagem Corporal , Estudos de Coortes , Obesidade/complicações , Índice de Massa Corporal , Hipertensão/epidemiologia , Hipertensão/complicações , Peso Corporal
12.
BMJ Open Diabetes Res Care ; 12(2)2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38453238

RESUMO

INTRODUCTION: This study aimed to, first, determine the clusters of sex hormones, liver enzymes, and cardiometabolic factors associated with postprandial glucose (PPG) and, second to evaluate the variation these clusters account for jointly and independently with polygenic risk scores (PRSs) in South Africans of African ancestry men and women. RESEARCH DESIGN AND METHODS: PPG was calculated as the integrated area under the curve for glucose during the oral glucose tolerance test (OGTT) using the trapezoidal rule in 794 participants from the Middle-aged Soweto Cohort. Principal component analysis was used to cluster sex hormones, liver enzymes, and cardiometabolic factors, stratified by sex. Multivariable linear regression was used to assess the proportion of variance in PPG accounted for by principal components (PCs) and type 2 diabetes (T2D) PRS while adjusting for selected covariates in men and women. RESULTS: The T2D PRS did not contribute to the PPG variability in both men and women. In men, the PCs' cluster of sex hormones, liver enzymes, and cardiometabolic explained 10.6% of the variance in PPG, with PC1 (peripheral fat), PC2 (liver enzymes and steroid hormones), and PC3 (lipids and peripheral fat) contributing significantly to PPG. In women, PC factors of sex hormones, cardiometabolic factors, and liver enzymes explained a similar amount of the variance in PPG (10.8%), with PC1 (central fat) and PC2 (lipids and liver enzymes) contributing significantly to PPG. CONCLUSIONS: We demonstrated that inter-individual differences in PPG responses to an OGTT may be differentially explained by body fat distribution, serum lipids, liver enzymes, and steroid hormones in men and women.


Assuntos
Doenças Cardiovasculares , Diabetes Mellitus Tipo 2 , Masculino , Pessoa de Meia-Idade , Humanos , Feminino , Glucose , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/genética , Glicemia , África do Sul/epidemiologia , Hormônios Esteroides Gonadais , Esteroides , Fígado , Lipídeos
13.
medRxiv ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38293229

RESUMO

BACKGROUND: Genome-wide association studies (GWAS) have predominantly focused on populations of European and Asian ancestry, limiting our understanding of genetic factors influencing kidney disease in Sub-Saharan African (SSA) populations. This study presents the largest GWAS for urinary albumin-to-creatinine ratio (UACR) in SSA individuals, including 8,970 participants living in different African regions and an additional 9,705 non-resident individuals of African ancestry from the UK Biobank and African American cohorts. METHODS: Urine biomarkers and genotype data were obtained from two SSA cohorts (AWI-Gen and ARK), and two non-resident African-ancestry studies (UK Biobank and CKD-Gen Consortium). Association testing and meta-analyses were conducted, with subsequent fine-mapping, conditional analyses, and replication studies. Polygenic scores (PGS) were assessed for transferability across populations. RESULTS: Two genome-wide significant (P<5x10-8) UACR-associated loci were identified, one in the BMP6 region on chromosome 6, in the meta-analysis of resident African individuals, and another in the HBB region on chromosome 11 in the meta-analysis of non-resident SSA individuals, as well as the combined meta-analysis of all studies. Replication of previous significant results confirmed associations in known UACR-associated regions, including THB53, GATM, and ARL15. PGS estimated using previous studies from European ancestry, African ancestry, and multi-ancestry cohorts exhibited limited transferability of PGS across populations, with less than 1% of observed variance explained. CONCLUSION: This study contributes novel insights into the genetic architecture of kidney disease in SSA populations, emphasizing the need for conducting genetic research in diverse cohorts. The identified loci provide a foundation for future investigations into the genetic susceptibility to chronic kidney disease in underrepresented African populations Additionally, there is a need to develop integrated scores using multi-omics data and risk factors specific to the African context to improve the accuracy of predicting disease outcomes. METHODS: Urine biomarkers and genotype data were obtained from two SSA cohorts (AWI-Gen and ARK), and two non-resident African-ancestry studies (UK Biobank and CKD-Gen Consortium). Association testing and meta-analyses were conducted, with subsequent fine-mapping, conditional analyses, and replication studies. Polygenic scores (PGS) were assessed for transferability across populations. RESULTS: Two genome-wide significant (P<5x10-8) UACR-associated loci were identified, one in the BMP6 region on chromosome 6, in the meta-analysis of resident African individuals, and another in the HBB region on chromosome 11 in the meta-analysis of non-resident SSA individuals, as well as the combined meta-analysis of all studies. Replication of previous significant results confirmed associations in known UACR-associated regions, including THB53, GATM, and ARL15. PGS estimated using previous studies from European ancestry, African ancestry, and multi-ancestry cohorts exhibited limited transferability of PGS across populations, with less than 1% of observed variance explained. CONCLUSION: This study contributes novel insights into the genetic architecture of kidney function in SSA populations, emphasizing the need for conducting genetic research in diverse cohorts. The identified loci provide a foundation for future investigations into the genetic susceptibility to chronic kidney disease in underrepresented African populations.

14.
Nat Commun ; 14(1): 8376, 2023 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-38104120

RESUMO

Most hypertension-related genome-wide association studies (GWASs) focus on non-African populations, despite hypertension (a major risk factor for cardiovascular disease) being highly prevalent in Africa. The AWI-Gen study GWAS meta-analysis for blood pressure (BP)-related traits (systolic and diastolic BP, pulse pressure, mean-arterial pressure and hypertension) from three sub-Saharan African geographic regions (N = 10,775), identifies two novel genome-wide significant signals (p < 5E-08): systolic BP near P2RY1 (rs77846204; intergenic variant, p = 4.95E-08) and pulse pressure near LINC01256 (rs80141533; intergenic variant, p = 1.76E-08). No genome-wide signals are detected for the AWI-Gen GWAS meta-analysis with previous African-ancestry GWASs (UK Biobank (African), Uganda Genome Resource). Suggestive signals (p < 5E-06) are observed for all traits, with 29 SNPs associating with more than one trait and several replicating known associations. Polygenic risk scores (PRSs) developed from studies on different ancestries have limited transferability, with multi-ancestry PRS providing better prediction. This study provides insights into the genetics of BP variation in African populations.


Assuntos
Estudo de Associação Genômica Ampla , Hipertensão , Humanos , Pressão Sanguínea/genética , Hipertensão/epidemiologia , Hipertensão/genética , População Negra/genética , Uganda , Polimorfismo de Nucleotídeo Único
15.
J Nutr ; 153(9): 2736-2743, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37451558

RESUMO

BACKGROUND: Earlier age at menarche is associated with behavioral and noncommunicable disease risks. The influence of birth weight (BW) (intrauterine) and postnatal growth on age at menarche is not well studied in low- and middle-income countries (LMICs). OBJECTIVE: Therefore, we investigated these associations in 5 LMIC birth cohorts. METHODS: We analyzed data from Brazil, Guatemala, India, the Philippines, and South Africa (n = 3983). We derived stunting (< -2 SD scores) at 24 mo using the WHO child growth standards. We generated interaction terms with categorized BW and conditional weight (lighter < 0 or heavier ≥ 0), and height (shorter < 0 or taller ≥ 0) z-scores. We categorized early-, modal-, and late-onset menarche and used multilevel ordinal regression. We used multilevel linear regression on continuous age at menarche. RESULTS: Mean age at menarche was 12.8 y (95% CI: 12.7 12.9). BW was not associated with age at menarche. Conditional height at 24 mo and mid-childhood (OR: 1.35; 95% CI: 1.27, 1.44 and 1.32; 1.25, 1.41, respectively) and conditional weight at 24 mo and mid-childhood (OR: 1.15; 1.08, 1.22 and 1.18; 1.11, 1.25, respectively) were associated with increased likelihood of early-onset menarche. Being heavier at birth and taller at 24 mo was associated with a 4-mo (95% CI: 0.8, 7.6) earlier age at menarche than being lighter at birth and shorter at 24 mo. Being heavier at birth but lighter in mid-childhood was associated with a 3-mo (95% CI: 0.8, 4.8) later age at menarche than being lighter at birth and mid-childhood. Age at menarche was 7 mo later in stunted than nonstunted girls. CONCLUSION: Age at menarche is inversely related to relative weight gain but also to rapid linear growth among those born shorter but remained stunted, and those born taller and grew excessively. These findings do not deter the global health goal to reduce growth faltering but emphasize the potential adverse effects of an obesogenic environment on adolescent development.


Assuntos
Países em Desenvolvimento , Menarca , Criança , Recém-Nascido , Feminino , Adolescente , Humanos , Lactente , Estudos Prospectivos , Peso ao Nascer , Desenvolvimento Infantil , Estatura
16.
Curr Osteoporos Rep ; 21(4): 360-371, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37351757

RESUMO

PURPOSE: To review the rising prevalence of osteopenia and osteoporosis in sub-Saharan Africa and the challenges this poses to governments and healthcare services. Using existing studies, we compare the prevalence of osteopenia and osteoporosis in men and women from sub-Saharan Africa to US and UK cohorts. Context-specific disparities in healthcare are discussed particularly the challenges in diagnosis and treatment of osteoporosis. RECENT FINDINGS: There are few epidemiological data describing the burden of osteoporosis in sub-Saharan Africa. In the studies and cohorts presented here, osteoporosis prevalence varies by sex, country and area of residence, but is generally higher in African populations, than has previously been appreciated. Risk factors contributing to poorer bone health include HIV, malnutrition and "inflammaging." Reprioritization towards care of ageing populations is urgently required. Equitable access to implementable preventative strategies, diagnostic services, treatments and pathways of care for bone health (for example embedded within HIV services) need now to be recognized and addressed by policy makers.


Assuntos
Doenças Ósseas Metabólicas , Infecções por HIV , Osteoporose , Masculino , Humanos , Feminino , Infecções por HIV/epidemiologia , Prevalência , África Subsaariana/epidemiologia , Osteoporose/epidemiologia , Doenças Ósseas Metabólicas/epidemiologia , Reino Unido/epidemiologia
17.
Maturitas ; 172: 60-68, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37116348

RESUMO

OBJECTIVE: To compare the risk factors for cardiometabolic disease between pre- and postmenopausal women from four sub-Saharan African countries. STUDY DESIGN: This cross-sectional study included 3609 women (1740 premenopausal and 1869 postmenopausal) from sites in Ghana (Navrongo), Burkina Faso (Nanoro), Kenya (Nairobi), and South Africa (Soweto and Dikgale). Demographic, anthropometric and cardiometabolic variables were compared between pre- and postmenopausal women, within and across sites using multivariable regression analyses. The sites represent populations at different stages of the health transition, with those in Ghana and Burkina Faso being rural, whilst those in Kenya and South Africa are more urbanised. MAIN OUTCOME MEASURES: Anthropometric and cardiometabolic variables. RESULTS: The prevalence rates of risk factors for cardiometabolic disease were higher in South (Soweto and Dikgale) and East (Nairobi) Africa than in West Africa (Nanoro and Navrongo), irrespective of menopausal status. Regression models in combined West African populations demonstrated that postmenopausal women had a larger waist circumference (ß = 1.28 (95 % CI: 0.58; 1.98) cm), log subcutaneous fat (ß =0.15 (0.10; 0.19)), diastolic (ß = 3.04 (1.47; 4.62) mm Hg) and log systolic (ß = 0.04 (0.02; 0.06)) blood pressure, log carotid intima media thickness (ß = 0.03 (0.01; 0.06)), low-density lipoprotein cholesterol (ß = 0.14 (0.04; 0.23) mmol/L) and log triglyceride (ß= 0.10 (0.04; 0.16)) levels than premenopausal women. No such differences were observed in the South and East African women. CONCLUSIONS: Menopause-related differences in risk factors for cardiometabolic disease were prominent in West but not East or South African study sites. These novel findings should inform cardiometabolic disease prevention strategies in midlife women specific to rural and urban and peri-urban locations in sub-Saharan Africa.


Assuntos
Doenças Cardiovasculares , Pós-Menopausa , Humanos , Feminino , Estudos Transversais , Espessura Intima-Media Carotídea , África do Sul/epidemiologia , Quênia , Fatores de Risco , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia
18.
BMJ Open ; 13(4): e069193, 2023 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-37105688

RESUMO

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.


Assuntos
Diabetes Mellitus , Hipertensão , Pessoa de Meia-Idade , Adulto , Humanos , Estudos Transversais , Glicemia , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/terapia , Hipertensão/epidemiologia , África Subsaariana/epidemiologia , Prevalência
19.
Bone ; 170: 116725, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36871897

RESUMO

OBJECTIVES: Bone age (BA) measurement in children is used to evaluate skeletal maturity and helps in the diagnosis of growth disorders in children. The two most used methods are Greulich and Pyle (GP), and Tanner and Whitehouse 3 (TW3), both based upon assessment of a hand-wrist radiograph. To our knowledge no study has compared and validated the two methods in sub-Saharan Africa (SSA), and only a few have determined BA despite it being a region where skeletal maturity is often impaired for example by HIV and malnutrition. This study aimed to compare BA as measured by two methods (GP and TW3) against chronological age (CA) and determine which method is most applicable in peripubertal children in Zimbabwe. METHODS: We conducted a cross-sectional study of boys and girls who tested negative for HIV. Children and adolescents were recruited by stratified random sampling from six schools in Harare, Zimbabwe. Non-dominant hand-wrist radiographs were taken, and BA assessed manually using both GP and TW3. Paired sample Student t-tests were used to calculate the mean differences between BA and chronological age (CA) in boys and girls. Bland-Altman plots compared CA to BA as determined by both methods, and agreement between GP and TW3 BA. All radiographs were graded by a second radiographer and 20 % of participants of each sex were randomly selected and re-graded by the first observer. Intraclass correlation coefficient assessed intra- and inter-rater reliability and coefficient of variation assessed precision. RESULTS: We recruited 252 children (111 [44 %] girls) aged 8.0-16.5 years. The boys and girls were of similar mean ± SD CA (12.2 ± 2.4 and 11.7 ± 1.9 years) and BA whether assessed by GP (11.5 ± 2.8 and 11.5 ± 2.1 years) or TW3 (11.8 ± 2.5 and 11.8 ± 2.1 years). In boys BA was lower than CA by 0.76 years (95 % CI: -0.95, -0.57) when using GP, and by 0.43 years (95 % CI: -0.61, -0.24) when using TW3. Among the girls there was no difference between BA and CA by either GP [-0.19 years (95 % CI: -0.40, 0.03)] or TW3 [0.07 years (95 % CI: -0.16, 0.29)]. In both boys and girls, there were no systematic differences between CA and TW3 BA across age groups whereas agreement improved between CA and GP BA as children got older. Inter-operator precision was 1.5 % for TW3 and 3.7 % for GP (n = 252) and intra-operator precision was 1.5 % for TW3 and 2.4 % for GP (n = 52). CONCLUSION: The TW3 BA method had better precision than GP and did not systematically differ from CA, meaning that TW3 is the preferred method of assessment of skeletal maturity in Zimbabwean children and adolescents. TW3 and GP methods do not agree for estimates of BA and therefore cannot be used interchangeably. The systematic differences in GP BA assessments over age means it is not appropriate for use in all age groups or stages of maturity in this population.


Assuntos
Infecções por HIV , Masculino , Feminino , Adolescente , Humanos , Criança , Zimbábue , Reprodutibilidade dos Testes , Estudos Transversais , Radiografia , Infecções por HIV/diagnóstico por imagem
20.
BMJ Open ; 13(3): e067788, 2023 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-36918238

RESUMO

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.


Assuntos
Dislipidemias , Infecções por HIV , Hipertensão , Adulto , Pessoa de Meia-Idade , Masculino , Humanos , Feminino , Multimorbidade , Fatores de Risco , Estudos Transversais , Prevalência , Fatores Sexuais , Hipertensão/epidemiologia , África Subsaariana/epidemiologia , Dislipidemias/epidemiologia
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