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1.
Am J Obstet Gynecol ; 2024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38697337

RESUMEN

BACKGROUND: The Multi-Omics for Mothers and Infants consortium aims to improve birth outcomes. Preterm birth is a major obstetrical complication globally and causes significant infant and childhood morbidity and mortality. OBJECTIVE: We analyzed placental samples (basal plate, placenta or chorionic villi, and the chorionic plate) collected by the 5 Multi-Omics for Mothers and Infants sites, namely The Alliance for Maternal and Newborn Health Improvement Bangladesh, The Alliance for Maternal and Newborn Health Improvement Pakistan, The Alliance for Maternal and Newborn Health Improvement Tanzania, The Global Alliance to Prevent Prematurity and Stillbirth Bangladesh, and The Global Alliance to Prevent Prematurity and Stillbirth Zambia. The goal was to analyze the morphology and gene expression of samples collected from preterm and uncomplicated term births. STUDY DESIGN: The teams provided biopsies from 166 singleton preterm (<37 weeks' gestation) and 175 term (≥37 weeks' gestation) deliveries. The samples were fixed in formalin and paraffin embedded. Tissue sections from these samples were stained with hematoxylin and eosin and subjected to morphologic analyses. Other placental biopsies (n=35 preterm, 21 term) were flash frozen, which enabled RNA purification for bulk transcriptomics. RESULTS: The morphologic analyses revealed a surprisingly high rate of inflammation that involved the basal plate, placenta or chorionic villi, and the chorionic plate. The rate of inflammation in chorionic villus samples, likely attributable to chronic villitis, ranged from 25% (Pakistan site) to 60% (Zambia site) of cases. Leukocyte infiltration in this location vs in the basal plate or chorionic plate correlated with preterm birth. Our transcriptomic analyses identified 267 genes that were differentially expressed between placentas from preterm vs those from term births (123 upregulated, 144 downregulated). Mapping the differentially expressed genes onto single-cell RNA sequencing data from human placentas suggested that all the component cell types, either singly or in subsets, contributed to the observed dysregulation. Consistent with the histopathologic findings, gene ontology analyses highlighted the presence of leukocyte infiltration or activation and inflammatory responses in both the fetal and maternal compartments. CONCLUSION: The relationship between placental inflammation and preterm birth is appreciated in developed countries. In this study, we showed that this link also exists in developing geographies. In addition, among the participating sites, we found geographic- and population-based differences in placental inflammation and preterm birth, suggesting the importance of local factors.

2.
AIDS Behav ; 28(4): 1123-1136, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38353877

RESUMEN

Postpartum depression (PPD) affects nearly 20% of postpartum women in Sub-Saharan Africa (SSA), where HIV prevalence is high. Depression is associated with worse HIV outcomes in non-pregnant adults and mental health disorders may worsen HIV outcomes for postpartum women and their infants. PPD is effectively treated with psychosocial or pharmacologic interventions; however, few studies have evaluated the acceptability of treatment modalities in SSA. We analyzed interviews with 23 postpartum women with HIV to assess the acceptability of two depression treatments provided in the context of a randomized trial. Most participants expressed acceptability of treatment randomization and study visit procedures. Participants shared perceptions of high treatment efficacy of their assigned intervention. They reported ongoing HIV and mental health stigma in their communities and emphasized the importance of social support from clinic staff. Our findings suggest a full-scale trial of PPD treatment will be acceptable among women with HIV in Zambia.


Asunto(s)
Depresión Posparto , Trastorno Depresivo , Infecciones por VIH , Adulto , Femenino , Humanos , Embarazo , Depresión/terapia , Depresión Posparto/epidemiología , Trastorno Depresivo/complicaciones , Infecciones por VIH/complicaciones , Infecciones por VIH/epidemiología , Infecciones por VIH/psicología , Periodo Posparto , Resultado del Tratamiento , Ensayos Clínicos Controlados Aleatorios como Asunto
3.
BMC Infect Dis ; 24(Suppl 1): 600, 2024 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-38898466

RESUMEN

BACKGROUND: Southern African countries have the largest global burden of HIV and syphilis, with a high prevalence among women of reproductive age. Although antenatal screening is standard of care, syphilis screening has generally lagged behind HIV screening. We aimed to evaluate the performance and operational characteristics of two commercial dual HIV/syphilis point-of-care tests (POCTs) for simultaneous maternal HIV/syphilis screening. METHODS: A clinic-based evaluation of dual HIV/syphilis POCTs (SD Bioline and Chembio) was conducted at five primary healthcare centres (PHCs) in South Africa and Zambia. POCT results using capillary fingerprick blood were compared to reference laboratory syphilis and HIV serological assays. RESULTS: Three thousand four hundred twelve consenting pregnant women aged ≥ 18 years were enrolled. The prevalence of treponemal antibody seropositivity and HIV infection ranged from 3.7 to 9.9% (n = 253) and 17.8 to 21.3% (n = 643), respectively. Pooled sensitivity for syphilis compared to the reference assay was 66.0% (95%CI 57.7-73.4) with SD Bioline and 67.9% (95%CI 58.2-76.3) with Chembio. Pooled specificity for syphilis was above 98% with both POCTs. The sensitivities of SD Bioline and Chembio assays were 78.0% (95%CI 68.6-85.7) and 81.0% (95%CI 71.9-88.2), respectively compared to an active syphilis case definition of treponemal test positive with a rapid plasma reagin titre of ≥ 8. The negative predictive values (NPVs) based on various prevalence estimates for syphilis with both assays ranged from 97 to 99%. The pooled sensitivity for HIV was 92.1% (95%CI 89.4-94.2) with SD Bioline; and 91.5% (95%CI 88.2-93.9) with Chembio. The pooled specificities for HIV were 97.2% (95%CI 94.8-98.5) with SD Bioline and 96.7% (95%CI 95.1-97.8) with Chembio. The NPV based on various prevalence estimates for HIV with both assays was approximately 98%. Most participating women (91%) preferred dual POCTs over two single POCTs for HIV and syphilis, and healthcare providers gave favourable feedback on the utility of both assays at PHC level. CONCLUSIONS: Based on the need to improve antenatal screening coverage for syphilis, dual HIV/syphilis POCTs could be effectively incorporated into antenatal testing algorithms to enhance efforts towards elimination of mother-to-child transmission of these infections.


Asunto(s)
Infecciones por VIH , Complicaciones Infecciosas del Embarazo , Sensibilidad y Especificidad , Sífilis , Humanos , Zambia/epidemiología , Femenino , Sífilis/diagnóstico , Sífilis/epidemiología , Infecciones por VIH/diagnóstico , Infecciones por VIH/epidemiología , Embarazo , Sudáfrica/epidemiología , Adulto , Adulto Joven , Complicaciones Infecciosas del Embarazo/diagnóstico , Complicaciones Infecciosas del Embarazo/epidemiología , Adolescente , Sistemas de Atención de Punto , Atención Primaria de Salud , Pruebas en el Punto de Atención , Prevalencia , Tamizaje Masivo/métodos , Atención Prenatal , Pruebas Diagnósticas de Rutina/métodos , Prueba de Diagnóstico Rápido
4.
Stud Fam Plann ; 54(2): 379-401, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36727169

RESUMEN

Few longitudinal studies have measured contraceptive continuation past one year in sub-Saharan Africa. We surveyed 674 women who had been randomized to receive the three-month intramuscular contraceptive injectable (DMPA-IM), levonorgestrel (LNG) implant, or copper intrauterine device (IUD) during the Evidence for Contraceptive Options and HIV Outcomes (ECHO) trial in South Africa and Zambia and were subsequently followed for two additional years to explore method continuation, reasons for discontinuation, and access to implant and IUD removal services. We also conducted in-depth qualitative interviews with 39 participants. We estimated cumulative discontinuation probabilities using Kaplan-Meier estimates and assessed factors associated with discontinuation using Cox-proportional hazards models. The LNG implant continuation rate over the maximum 44-month study period was 60 percent, while rates for the copper IUD and DMPA-IM were 52 percent and 44 percent, respectively. Reasons for method discontinuation included side effects, particularly menstrual changes, and method stock-outs. Most implant and IUD users who sought removal were able to access services; however, room for improvement exists. In this cohort originally randomized to receive a contraceptive method and attend regular study visits, implants and IUDs continued to be highly acceptable over an additional two years, but facilities should continue to ensure that insertions and removals are available as requested.


Asunto(s)
Anticonceptivos Femeninos , Dispositivos Intrauterinos de Cobre , Femenino , Humanos , Levonorgestrel/efectos adversos , Dispositivos Intrauterinos de Cobre/efectos adversos , Sudáfrica , Zambia , Anticoncepción/métodos , Anticonceptivos Femeninos/efectos adversos
5.
Reprod Health ; 20(1): 65, 2023 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-37118835

RESUMEN

BACKGROUND: "Self-care" for sexual and reproductive health (SRH) includes contraceptive methods and other supplies that people can use with or without the support of a healthcare provider. Self-administered tests, self-injection of injectable contraception, or self-removal of intrauterine devices (IUDs) can increase people's access to and autonomy over their own SRH. Objectives of this study were to assess women's current interest in and use of SRH self-care and explore key informants' (KI) opinions of self-care, especially during the COVID-19 pandemic. METHODS: Data for this study came from female participants in the longitudinal Contraceptive Use Beyond ECHO (CUBE) study, and KIs, including healthcare providers, in South Africa and Zambia between September 2020 and June 2021. For this analysis, we used data from a participant phone survey (n = 537), and from in-depth interviews (IDIs) completed with a sub-sample of women (n = 39) and KIs (n = 36). Survey data were analyzed with descriptive statistics, and IDI data were analyzed using applied thematic analysis. RESULTS: Female survey participants in South Africa were more interested in learning about emergency contraceptive pills, subcutaneous injectable contraception, and CycleBeads, while Zambian participants wanted more information and access to condoms. However, in IDIs in both countries, women described minimal experience with self-care beyond condom use. In the Zambian KI IDIs, COVID-19 led to increased self-care counseling on subcutaneous injectable contraception and HIV self-testing. KIs who do not counsel on self-care were concerned that women may harm themselves or blame the provider for difficulties. Two KIs thought that women could possibly self-remove IUDs, but most expressed concerns. Reported barriers to self-care included COVID movement restrictions, transport costs, lack of accessible pharmacies, women's low awareness, and possible stigma. CONCLUSIONS: Women surveyed reported interest in learning more about SRH self-care methods and resources, but in IDIs did not report extensive previous use besides condoms. KIs described some concerns about women's ability to use self-care methods. Counseling on and provision of self-care methods and supplies may have increased during the COVID-19 pandemic, but ensuring that self-care is more than just a temporary measure in health systems has the potential to increase access to SRH care and support women's autonomy and healthcare needs.


BACKGROUND: "Self-care" refers to healthcare that does not have to be given by a provider, but that people can use themselves. In sexual and reproductive health (SRH), this includes medicines or supplies like pills and injections that people can use to prevent or test for pregnancy or sexually transmitted infections. This study wanted to better understand women's interest in and use of SRH self-care and explore key informants' opinions of self-care, especially during the COVID-19 pandemic. METHODS: We surveyed 537 women in KwaZulu-Natal province, South Africa and Lusaka, Zambia in 2020­2021. We also conducted interviews with 39 women and 36 key informants, including healthcare providers, government officials, and community advocates. RESULTS: Women surveyed in South Africa were more interested than those in Zambia in learning more about self-care contraception, especially daily pills, emergency pills, and injections they could give themselves. In interviews, some key informants said that they do not tell women about self-care because they worried that women could hurt themselves or blame the provider if they experienced problems. COVID movement restrictions, transport costs, and inaccessible pharmacies were all barriers that key informants mentioned to accessing tests, tools, or contraceptive methods that women could give or use themselves. CONCLUSIONS: Women surveyed were interested in learning more about self-care and those interviewed reported minimal previous use of self-care methods besides condoms. Providers also have some concerns about women's ability to use self-care methods. Counseling on and providing self-care methods and supplies may have increased during COVID-19, but increasing access to self-care could help more women take care of their own sexual and reproductive healthcare.


Asunto(s)
COVID-19 , Salud Reproductiva , Femenino , Humanos , Zambia/epidemiología , Sudáfrica , Pandemias , Anticoncepción , Personal de Salud
6.
Epidemiology ; 33(3): 422-430, 2022 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-35067569

RESUMEN

BACKGROUND: A trial of progesterone to prevent preterm birth among HIV-infected Zambian women [Improving Pregnancy Outcomes with Progesterone (IPOP)] found no treatment effect, but the risk of the primary outcome was among the lowest ever documented in women with HIV. In this secondary analysis, we compare the risks of preterm birth (<37 weeks), stillbirth, and a composite primary outcome comprising the two in IPOP versus an observational pregnancy cohort [Zambian Preterm Birth Prevention Study (ZAPPS)] in Zambia, to evaluate reasons for the low risk in IPOP. METHODS: Both studies enrolled women before 24 gestational weeks, during August 2015-September 2017 (ZAPPS) and February 2018-January 2020 (IPOP). We used linear probability and log-binomial regression to estimate risk differences and risk ratios (RR), before and after restriction and standardization with inverse probability weights. RESULTS: The unadjusted risk of composite outcome was 18% in ZAPPS (N = 1450) and 9% in IPOP (N = 791) (RR = 2.0; 95% CI = 1.6, 2.6). After restricting and standardizing the ZAPPS cohort to the distribution of IPOP baseline characteristics, the risk remained higher in ZAPPS (RR = 1.6; 95% CI = 1.0, 2.4). The lower risk of preterm/stillbirth in IPOP was only partially explained by measured risk factors. CONCLUSIONS: Possible benefits in IPOP of additional monetary reimbursement, more frequent visits, and group-based care warrant further investigation.


Asunto(s)
Infecciones por VIH , Complicaciones del Embarazo , Nacimiento Prematuro , Femenino , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/epidemiología , Humanos , Recién Nacido , Embarazo , Resultado del Embarazo/epidemiología , Mujeres Embarazadas , Nacimiento Prematuro/epidemiología , Nacimiento Prematuro/prevención & control , Zambia/epidemiología
7.
AIDS Care ; 34(4): 478-485, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34180277

RESUMEN

Current guidelines recommend starting antiretroviral therapy (ART) as soon as possible after HIV diagnosis to reduce morbidity, mortality and onward HIV transmission. We examined factors influencing ART initiation by women who seroconverted during the Evidence for Contraceptive Options and HIV Outcomes (ECHO) Trial. ECHO, conducted between 2015 and 2018, enrolled HIV-negative, sexually active women, aged 16-35 years, from four African countries. Follow-up was 12-18 months, with quarterly HIV testing. Women with incident HIV infection received extensive counselling by trial staff and referral to local facilities for HIV care. Of 304 women with ≥90 days follow-up time since HIV diagnosis, 186(61.2%) initiated ART within 90 days, 69(22.7%) initiated after 90 days, and 49(16.1%) had not initiated by the end of the study. There were no statistically significant differences in characteristics among women who initiated ART ≤90 days versus those who did not. Frequent reasons for delayed or non-initiation of ART included not feeling ready to start ART and being newly diagnosed. In a large clinical trial, ART initiation was modest within 90 days of HIV diagnosis and grew to 84% with longer observation. Despite extensive counselling on the importance of early ART initiation, personal barriers delayed some women from starting ART.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Adolescente , Adulto , África del Sur del Sahara , Fármacos Anti-VIH/uso terapéutico , Anticonceptivos/uso terapéutico , Consejo , Femenino , Infecciones por VIH/diagnóstico , Infecciones por VIH/tratamiento farmacológico , Humanos , Adulto Joven
8.
BMC Pregnancy Childbirth ; 21(1): 534, 2021 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-34320947

RESUMEN

BACKGROUND: Maternal HIV increases the risk of adverse birth outcomes including preterm birth, fetal growth restriction, and stillbirth, but the biological mechanism(s) underlying this increased risk are not well understood. We hypothesized that maternal HIV may lead to adverse birth outcomes through an imbalance in angiogenic factors involved in the vascular endothelial growth factor (VEGF) signaling pathway. METHODS: In a case-control study nested within an ongoing cohort in Zambia, our primary outcomes were serum concentrations of VEGF-A, soluble endoglin (sEng), placental growth factor (PlGF), and soluble fms-like tyrosine kinase-1 (sFLT-1). These were measured in 57 women with HIV (cases) and 57 women without HIV (controls) before 16 gestational weeks. We used the Wilcoxon rank-sum and linear regression controlling for maternal body mass index (BMI) and parity to assess the difference in biomarker concentrations between cases and controls. We also used logistic regression to test for associations between biomarker concentration and adverse pregnancy outcomes (preeclampsia, preterm birth, small for gestational age, stillbirth, and a composite of preterm birth or stillbirth). RESULTS: Compared to controls, women with HIV had significantly lower median concentrations of PlGF (7.6 vs 10.2 pg/mL, p = 0.02) and sFLT-1 (1647.9 vs 2055.6 pg/mL, p = 0.04), but these findings were not confirmed in adjusted analysis. PlGF concentration was lower among women who delivered preterm compared to those who delivered at term (6.7 vs 9.6 pg/mL, p = 0.03) and among those who experienced the composite adverse birth outcome (6.2 vs 9.8 pg/mL, p = 0.02). Median sFLT-1 concentration was lower among participants with the composite outcome (1621.0 vs 1945.9 pg/mL, p = 0.04), but the association was not significant in adjusted analysis. sEng was not associated with either adverse birth outcomes or HIV. VEGF-A was undetectable by Luminex in all specimens. CONCLUSIONS: We present preliminary findings that HIV is associated with a shift in the VEGF signaling pathway in early pregnancy, although adjusted analyses were inconclusive. We confirm an association between angiogenic biomarkers and adverse birth outcomes in our population. Larger studies are needed to further elucidate the role of HIV on placental angiogenesis and adverse birth outcomes.


Asunto(s)
Endoglina/sangre , Infecciones por VIH/sangre , Factor de Crecimiento Placentario/sangre , Complicaciones Infecciosas del Embarazo/sangre , Resultado del Embarazo/epidemiología , Factor A de Crecimiento Endotelial Vascular/sangre , Receptor 1 de Factores de Crecimiento Endotelial Vascular/sangre , Adulto , Inductores de la Angiogénesis , Biomarcadores/sangre , Estudios de Casos y Controles , Femenino , Humanos , Placenta/irrigación sanguínea , Embarazo , Nacimiento Prematuro/epidemiología , Zambia/epidemiología
9.
Trop Med Int Health ; 22(3): 332-339, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-28102027

RESUMEN

OBJECTIVE: To describe engagement along the HIV continuum of care using a large network of clinics in Zambia. METHODS: We employed a practical framework to describe retention along the HIV treatment cascade, using routinely collected clinical data available in resource-constrained settings. We included health facilities in four Zambian provinces with more than 300 enrolled patients over the age of 5 years. We described attrition at each step, from HIV enrolment to 720 days after ART initiation. The population was further stratified by year of enrolment to describe temporal trends in patient engagement. RESULTS: From January 2004 to December 2014, 444 439 individuals over the age of 5 years sought HIV care at 75 eligible health facilities. Among those enrolled into HIV care, 82.1% (95% confidence interval [CI]: 79.4-84.5%) were fully assessed for ART eligibility within 180 days of enrolment and 63.6% (95% CI: 61.7-65.3) were found to be eligible for ART based on the HIV treatment guidelines at the time. Of those patients eligible for ART, 81.1% (95% CI: 79.5-82.7%) initiated ART within 180 days. Patient retention in ART programme was 81.2% (95% CI: 80.4-81.9%) at 90 days, 70.0% (95% CI: 68.7-71.2%) at 360 days and 61.6% (95% CI: 60.0-63.2%) at 720 days. We noted a steady decline in proportions assessed for ART eligibility and deemed eligible for ART in the time frame. Proportions that started ART and remained in care remained relatively consistent. CONCLUSION: We describe a simple approach for assessing patient engagement after enrolment into HIV care. Using limited types of data routinely available, we demonstrate an important and replicable approach to monitoring programmes in resource-constrained settings.


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Continuidad de la Atención al Paciente , Infecciones por VIH/tratamiento farmacológico , Instituciones de Salud , Pacientes Desistentes del Tratamiento/estadística & datos numéricos , Adulto , Femenino , Recursos en Salud , Humanos , Masculino , Aceptación de la Atención de Salud , Evaluación de Programas y Proyectos de Salud/métodos , Zambia
10.
Sex Transm Dis ; 41(2): 123-8, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24413493

RESUMEN

BACKGROUND: The vaginal microbiota may play a role in mediating susceptibility to sexually transmitted infections, including Trichomonas vaginalis (TV). METHODS: Data were analyzed from HIV-1-seronegative women participating in HIV Prevention Trials Network Protocol 035. At quarterly visits for up to 30 months, participants completed structured interviews and specimens were collected for genital tract infection testing. T. vaginalis was detected by saline microscopy. Bacterial vaginosis (BV) was characterized by Gram stain using the Nugent score (BV = 7-10; intermediate = 4-6; normal = 0-3 [reference group]). Cox proportional hazards models stratified by study site were used to assess the association between Nugent score category at the prior quarterly visit and TV acquisition. RESULTS: In this secondary analysis, 2920 participants from Malawi, South Africa, United States, Zambia, and Zimbabwe contributed 16,259 follow-up visits. Bacterial vaginosis was detected at 5680 (35%) visits, and TV was detected at 400 (2.5%) visits. Adjusting for age, marital status, hormonal contraceptive use, unprotected sex in the last week and TV at baseline, intermediate Nugent score, and BV at the prior visit were associated with an increased risk of TV (intermediate score: adjusted hazard ratio [aHR], 1.73; 95% confidence interval [CI], 1.21-2.19; BV: aHR, 2.40; 95% CI, 1.92-3.00). Sensitivity analyses excluding 211 participants with TV at baseline were similar to those from the full study population (intermediate score: aHR, 1.54; 95% CI, 1.10-2.14; BV: aHR, 2.23; 95% CI, 1.75-2.84). CONCLUSIONS: Women with a Nugent score higher than 3 were at an increased risk for acquiring TV. If this relationship is causal, interventions that improve the vaginal microbiota could contribute to reductions in TV incidence.


Asunto(s)
Seronegatividad para VIH/inmunología , Vaginitis por Trichomonas/microbiología , Trichomonas vaginalis/aislamiento & purificación , Vagina/microbiología , Vaginosis Bacteriana/microbiología , Adulto , África/epidemiología , Femenino , Estudios de Seguimiento , Humanos , Incidencia , Persona de Mediana Edad , Medición de Riesgo , Vaginitis por Trichomonas/epidemiología , Vaginitis por Trichomonas/inmunología , Estados Unidos/epidemiología , Frotis Vaginal , Vaginosis Bacteriana/epidemiología , Vaginosis Bacteriana/inmunología
11.
Int J Gynaecol Obstet ; 165(3): 1013-1021, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38189177

RESUMEN

OBJECTIVE: Low-cost devices have made obstetric sonography possible in settings where it was previously unfeasible, but ensuring quality and consistency at scale remains a challenge. In the present study, we sought to create a tool to reduce substandard fetal biometry measurement while minimizing care disruption. METHODS: We developed a deep learning artificial intelligence (AI) model to estimate gestational age (GA) in the second and third trimester from fly-to cineloops-brief videos acquired during routine ultrasound biometry-and evaluated its performance in comparison to expert sonographer measurement. We then introduced random error into fetal biometry measurements and analyzed the ability of the AI model to flag grossly inaccurate measurements such as those that might be obtained by a novice. RESULTS: The mean absolute error (MAE) of our model (±standard error) was 3.87 ± 0.07 days, compared to 4.80 ± 0.10 days for expert biometry (difference -0.92 days; 95% CI: -1.10 to -0.76). Based on simulated novice biometry with average absolute error of 7.5%, our model reliably detected cases where novice biometry differed from expert biometry by 10 days or more, with an area under the receiver operating characteristics curve of 0.93 (95% CI: 0.92, 0.95), sensitivity of 81.0% (95% CI: 77.9, 83.8), and specificity of 89.9% (95% CI: 88.1, 91.5). These results held across a range of sensitivity analyses, including where the model was provided suboptimal truncated fly-to cineloops. CONCLUSIONS: Our AI model estimated GA more accurately than expert biometry. Because fly-to cineloop videos can be obtained without any change to sonographer workflow, the model represents a no-cost guardrail that could be incorporated into both low-cost and commercial ultrasound devices to prevent reporting of most gross GA estimation errors.


Asunto(s)
Aprendizaje Profundo , Edad Gestacional , Ultrasonografía Prenatal , Humanos , Ultrasonografía Prenatal/normas , Ultrasonografía Prenatal/métodos , Embarazo , Femenino , Control de Calidad , Grabación en Video , Biometría/métodos , Tercer Trimestre del Embarazo , Segundo Trimestre del Embarazo
13.
Contracept X ; 5: 100089, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36718374

RESUMEN

Objectives: To assess differences in HIV testing at 6-months intervals over 24 months among intramuscular depot medroxyprogesterone acetate (DMPA-IM) injectable, levonorgestrel implant, or copper intrauterine devices (IUD) users in KwaZulu-Natal, South Africa, and Lusaka, Zambia. Testing at recommended intervals has not been previously assessed in long-acting reversible contraceptive (LARC) users (implant and IUD users) compared to those using effective but shorter-acting methods (such as DMPA-IM) in sub-Saharan Africa. Study design: As part of the longitudinal contraceptive use beyond ECHO (CUBE) study, we measured HIV testing over 24 months. Participants were considered continuous users of DMPA-IM, levonorgestrel implant, or copper IUD if they used the same method across all months of their study participation, or not continuous users of their baseline CUBE method if they switched or discontinued their method. We used multivariable logistic regression models with generalized estimating equations and robust standard errors, stratified by country, to assess differences in HIV testing. Results: Among the 498 participants, HIV testing rates were higher in Zambia for all methods compared to South Africa. In bivariate analyses, continuous implant or IUD users (the LARC users) were significantly less likely to report having received HIV testing at the 6-months and 24-months surveys, compared to continuous DMPA-IM users. In adjusted longitudinal models, continuous IUD users (adjusted odds ratio: 0.42, 95% CI: 0.24, 0.74), continuous implant users (adjusted odds ratio: 0.23, 95% CI: 0.12, 0.42) in South Africa had significantly lower odds of HIV testing compared to continuous DMPA-IM users. There were no significant differences in Zambia in the adjusted models. Conclusion: LARC use may reduce opportunities for HIV testing and users should be counseled on regular HIV testing and the option of HIV self-testing. Implications: Due to infrequent clinical contacts which may lead to lower rates of HIV testing at recommended intervals, LARC users should be provided opportunities to test for HIV at home or when seeking other health services.

14.
Int J Gynaecol Obstet ; 161(2): 462-469, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36263879

RESUMEN

OBJECTIVE: To compare the performance of mid upper arm circumference (MUAC) and body mass index (BMI) for prediction of small for gestational age (SGA) in Zambia. METHODS: This is a secondary analysis of an ongoing clinical cohort that included women with a single gestation and MUAC measured before 24 weeks of pregnancy. We assessed relationships between maternal MUAC and birth weight centile using regression. The performance of MUAC and BMI to predict SGA was compared using receiver operating characteristic curves and the effect of maternal HIV was investigated in sub-group analyses. RESULTS: Of 1117 participants, 847 (75%) were HIV-negative (HIV-) and 270 (24%) were HIV-positive (HIV+). Seventy-four (7%) delivered severe SGA infants (<3rd centile), of whom 56 (76%) were HIV- and 18 (24%) were HIV+ (odds ratio [OR] 1.01, 95% confidence interval [CI] 0.58-1.75). MUAC was associated with higher birth weight centile (+1.2 centile points, 95% CI 0.7-1.6; P < 0.001); this relationship was stronger among HIV+ women (+1.7 centile points, 95% CI 0.8-2.6; P < 0.001) than HIV- women (+0.9 centile points, 95% CI 0.4-1.4; P = 0.001). The discriminatory power was similar, albeit poor (area under the curve [AUC] < 0.7), between MUAC and BMI for the prediction of SGA. In stratified analysis, MUAC and BMI showed excellent discrimination predicting severe SGA among HIV+ (AUC 0.83 and 0.81, respectively) but not among HIV- women (AUC 0.64 and 0.63, respectively). CONCLUSION: Maternal HIV infection increased the discrimination of both early pregnancy MUAC and BMI for prediction of severe SGA in Zambia. CLINICAL TRIAL NUMBER: ClinicalTrials.gov (NCT02738892).


Asunto(s)
Infecciones por VIH , Enfermedades del Recién Nacido , Femenino , Humanos , Lactante , Recién Nacido , Embarazo , Antropometría , Brazo/anatomía & histología , Peso al Nacer , Retardo del Crecimiento Fetal , Edad Gestacional , Infecciones por VIH/complicaciones , Zambia
15.
Int J Gynaecol Obstet ; 160(3): 842-849, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35899762

RESUMEN

OBJECTIVE: To illustrate the difference between exposure effects and population attributable effects. METHODS: We examined the effect of mid-pregnancy short cervical length (<25 mm) on preterm birth using data from a prospective cohort of pregnant women in Lusaka, Zambia. Preterm birth was live birth or stillbirth before 37 weeks of pregnancy. For estimation, we used multivariable regression and parametric g-computation. RESULTS: Among 1409 women included in the analysis, short cervix was rare (2.4%); 13.6% of births were preterm. Exposure effect estimates were large (marginal risk ratio 2.86, 95% confidence interval [CI] 1.80-4.54), indicating that the preterm birth risk was substantially higher among women with a short cervix compared with women without a short cervix. However, the population attributable effect estimates were close to the null (risk ratio 1.06, 95% CI 1.02-1.10), indicating that an intervention to counteract the impact of short cervix on preterm birth would have minimal effect on the population risk of preterm birth. CONCLUSION: Although authors often refer to "the" effect, there are actually different types of effects, as we have illustrated here. In planning research, it is important to consider which effect to estimate to ensure that the estimate aligns with the research objective.


Asunto(s)
Nacimiento Prematuro , Femenino , Embarazo , Recién Nacido , Humanos , Nacimiento Prematuro/epidemiología , Nacimiento Prematuro/etiología , Cuello del Útero/diagnóstico por imagen , Estudios Prospectivos , Medición de Longitud Cervical , Zambia/epidemiología
16.
J Int AIDS Soc ; 26(3): e26075, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36929284

RESUMEN

INTRODUCTION: Couple HIV testing and counselling (CHTC) is associated with measurable benefits for HIV prevention and treatment. However, the uptake remains limited in much of sub-Saharan Africa, despite an expanded range of strategies designed to promote access. METHODS: Following PRIMSA guidelines, we conducted a systematic review to characterize CHTC uptake strategies. Five databases were searched. Full-text articles were included if they were: conducted in sub-Saharan Africa during the study period (1980-2019), targeted heterosexual couples, reported at least one strategy to promote CHTC and provided a quantifiable measure of CHTC uptake. After the initial and full-text screening, key features of the studies were abstracted and synthesized. RESULTS: Of the 6188 unique records found in our search, 365 underwent full-text review with 29 distinct studies included and synthesized. Most studies recruited couples through antenatal care (n = 11) or community venues (n = 8) and used provider-based HIV testing (n = 25). The primary demand creation strategies included home-based CHTC (n = 7); integration of CHTC into clinical settings (n = 4); distribution of HIV self-testing kits (n = 4); verbal or written invitations (n = 4); community recruiters (n = 3); partner tracing (n = 2); relationship counselling (n = 2); financial incentives (n = 1); group education with CHTC coupons (n = 1); and HIV testing at other community venues (n = 1). CHTC uptake ranged from negligible to nearly universal. DISCUSSION: We thematically categorized a diverse range of strategies with varying levels of intensity and resources used across sub-Saharan Africa to promote CHTC. Offering CHTC within couples' homes was the most common approach, followed by the integration of CHTC into clinical settings. Due to heterogeneity in study characteristics, we were unable to compare the effectiveness across studies, but several trends were observed, including the high prevalence of CHTC promotion strategies in antenatal settings and the promising effects of home-based CHTC, distribution of HIV self-tests and integration of CHTC into routine health services. Since 2019, an updated literature search found that combining partner notification and secondary distribution of HIV self-test kits may be an additionally effective CHTC strategy. CONCLUSIONS: There are many effective, feasible and scalable approaches to promote CHTC that should be considered by national programmes according to local needs, cultural context and available resources.


Asunto(s)
Infecciones por VIH , Parejas Sexuales , Humanos , Femenino , Embarazo , Infecciones por VIH/diagnóstico , Infecciones por VIH/epidemiología , Infecciones por VIH/prevención & control , Consejo , Prueba de VIH , África del Sur del Sahara
17.
Int J STD AIDS ; 34(14): 1004-1011, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37436402

RESUMEN

BACKGROUND: To meet global targets for the elimination of mother-to-child HIV transmission, tailored approaches to HIV testing strategies need prioritizing. Herein, we sought to identify individual-level factors associated with male partner HIV testing. METHODS: We conducted a secondary analysis of data from two parallel randomized trials of pregnant women living with HIV and those HIV-negative in Lusaka, Zambia. Across both trials, control groups received partner notification services only, while intervention groups received partner notification services plus HIV self-test kits for their partners. Associations between baseline factors and male partner testing were estimated using a probability difference. The outcome of interest was uptake of male partner HIV testing of any kind within 30 days of randomization. RESULTS: The parent study enrolled 326 participants. Among the 151 women in the control groups, no clear associations were noted between maternal or male partner characteristics and reported uptake of male partner HIV testing. There were positive trends favouring partner testing among women who completed primary school education, had larger households (>2 members), and whose partners were circumcised. Likewise, no clear predictors of male partner testing were identified among the 149 women in the intervention groups. However, negative trends favouring no testing were noted among older, multiparous women from larger households. CONCLUSION: No consistent predictors for male partner HIV testing across two compared strategies were observed. Our findings suggest that differentiated strategies for male partner HIV testing may not be necessary. Instead, consideration should be given to universal approaches when bringing such services to scale.


Asunto(s)
Infecciones por VIH , Autoevaluación , Humanos , Femenino , Masculino , Embarazo , Infecciones por VIH/diagnóstico , Infecciones por VIH/prevención & control , Trazado de Contacto , Parejas Sexuales , Transmisión Vertical de Enfermedad Infecciosa/prevención & control , Zambia/epidemiología , Prueba de VIH
18.
Gates Open Res ; 7: 50, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37868333

RESUMEN

Background: The Masimo Total Hemoglobin SpHb® is a continuous and non-invasive handheld device to measure hemoglobin levels. Previous research has found that SpHb is able to accurately detect hemoglobin levels in adult patients with a similar degree of bias and standard deviation to point-of-care invasive method measurements. Generally, limited clinical evidence, lack of validation of Masimo at higher than and lower than hemoglobin threshold values, and scientific consensus supporting the use of Masimo for accurate hemoglobin testing for the diagnosis of anemia during pregnancy calls for further research. Methods and analysis: The proposed prospective cohort will be nested within the ongoing Pregnancy Risk and Infant Surveillance and Measurement Alliance (PRISMA) Maternal and Newborn Health (MNH) study. Three study sites (located in Zambia, Kenya, and Pakistan) will participate and collect hemoglobin data at five time points (<20 weeks, 20 weeks, 28 weeks, 36 weeks' gestation, and six weeks postpartum). We will measure hemoglobin using a venous blood sample via hematology auto-analyzer complete blood count (gold standard) and the non-invasive device. The primary objective is to assess agreement between Masimo total hemoglobin and complete blood count and on a continuous scale using Intraclass Correlation Coefficient and Bland-Altman Analysis. The second objective is to assess agreement between the two measures on a binary scale using Positive Percentage Agreement and Negative Percentage Agreement, Cohen's Kappa, and McNemar Test. On an ordinal scale, agreement will be measured using Weighted Cohen's Kappa and Harrel's Concordance Index. Lastly, we will assess factors that might affect the accuracy of Masimo total hemoglobin using linear mixed models. Conclusions: The primary aim of this study is to assess the validity of the non-invasive Masimo device compared to the gold standard method of invasive hemoglobin measurements during pregnancy and postpartum periods for the diagnosis of anemia.


Asunto(s)
Anemia , Salud del Lactante , Adulto , Femenino , Humanos , Lactante , Recién Nacido , Embarazo , Recuento de Células Sanguíneas , Hemoglobinas/análisis , Estudios Prospectivos , Estudios Observacionales como Asunto
19.
Lancet Glob Health ; 11(6): e903-e916, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37202025

RESUMEN

BACKGROUND: Sputum is the most widely used sample to diagnose active tuberculosis, but many people living with HIV are unable to produce sputum. Urine, in contrast, is readily available. We hypothesised that sample availability influences the diagnostic yield of various tuberculosis tests. METHODS: In this systematic review and meta-analysis of individual participant data, we compared the diagnostic yield of point-of-care urine-based lipoarabinomannan tests with that of sputum-based nucleic acid amplification tests (NAATs) and sputum smear microscopy (SSM). We used microbiologically confirmed tuberculosis based on positive culture or NAAT from any body site as the denominator and accounted for sample provision. We searched PubMed, Web of Science, Embase, African Journals Online, and clinicaltrials.gov from database inception to Feb 24, 2022 for randomised controlled trials, cross-sectional studies, and cohort studies that assessed urine lipoarabinomannan point-of-care tests and sputum NAATs for active tuberculosis detection in participants irrespective of tuberculosis symptoms, HIV status, CD4 cell count, or study setting. We excluded studies in which recruitment was not consecutive, systematic, or random; provision of sputum or urine was an inclusion criterion; less than 30 participants were diagnosed with tuberculosis; early research assays without clearly defined cutoffs were tested; and humans were not studied. We extracted study-level data, and authors of eligible studies were invited to contribute deidentified individual participant data. The main outcomes were the tuberculosis diagnostic yields of urine lipoarabinomannan tests, sputum NAATs, and SSM. Diagnostic yields were predicted using Bayesian random-effects and mixed-effects meta-analyses. This study is registered with PROSPERO, CRD42021230337. FINDINGS: We identified 844 records, from which 20 datasets and 10 202 participants (4561 [45%] male participants and 5641 [55%] female participants) were included in the meta-analysis. All studies assessed sputum Xpert (MTB/RIF or Ultra, Cepheid, Sunnyvale, CA, USA) and urine Alere Determine TB LAM (AlereLAM, Abbott, Chicago, IL, USA) in people living with HIV aged 15 years or older. Nearly all (9957 [98%] of 10 202) participants provided urine, and 82% (8360 of 10 202) provided sputum within 2 days. In studies that enrolled unselected inpatients irrespective of tuberculosis symptoms, only 54% (1084 of 1993) of participants provided sputum, whereas 99% (1966 of 1993) provided urine. Diagnostic yield was 41% (95% credible interval [CrI] 15-66) for AlereLAM, 61% (95% Crl 25-88) for Xpert, and 32% (95% Crl 10-55) for SSM. Heterogeneity existed across studies in the diagnostic yield, influenced by CD4 cell count, tuberculosis symptoms, and clinical setting. In predefined subgroup analyses, all tests had higher yields in symptomatic participants, and AlereLAM yield was higher in those with low CD4 counts and inpatients. AlereLAM and Xpert yields were similar among inpatients in studies enrolling unselected participants who were not assessed for tuberculosis symptoms (51% vs 47%). AlereLAM and Xpert together had a yield of 71% in unselected inpatients, supporting the implementation of combined testing strategies. INTERPRETATION: AlereLAM, with its rapid turnaround time and simplicity, should be prioritised to inform tuberculosis therapy among inpatients who are HIV-positive, regardless of symptoms or CD4 cell count. The yield of sputum-based tuberculosis tests is undermined by people living with HIV who cannot produce sputum, whereas nearly all participants are able to provide urine. The strengths of this meta-analysis are its large size, the carefully harmonised denominator, and the use of Bayesian random-effects and mixed-effects models to predict yields; however, data were geographically restricted, clinically diagnosed tuberculosis was not considered in the denominator, and little information exists on strategies for obtaining sputum samples. FUNDING: FIND, the Global Alliance for Diagnostics.


Asunto(s)
Infecciones por VIH , Mycobacterium tuberculosis , Tuberculosis , Humanos , Masculino , Femenino , Esputo/microbiología , Teorema de Bayes , Estudios Transversales , Tuberculosis/diagnóstico , Tuberculosis/tratamiento farmacológico , Lipopolisacáridos/orina , Infecciones por VIH/complicaciones , Infecciones por VIH/diagnóstico , Sensibilidad y Especificidad
20.
Sci Adv ; 9(21): eade7692, 2023 05 24.
Artículo en Inglés | MEDLINE | ID: mdl-37224249

RESUMEN

Preterm birth (PTB) is the leading cause of death in children under five, yet comprehensive studies are hindered by its multiple complex etiologies. Epidemiological associations between PTB and maternal characteristics have been previously described. This work used multiomic profiling and multivariate modeling to investigate the biological signatures of these characteristics. Maternal covariates were collected during pregnancy from 13,841 pregnant women across five sites. Plasma samples from 231 participants were analyzed to generate proteomic, metabolomic, and lipidomic datasets. Machine learning models showed robust performance for the prediction of PTB (AUROC = 0.70), time-to-delivery (r = 0.65), maternal age (r = 0.59), gravidity (r = 0.56), and BMI (r = 0.81). Time-to-delivery biological correlates included fetal-associated proteins (e.g., ALPP, AFP, and PGF) and immune proteins (e.g., PD-L1, CCL28, and LIFR). Maternal age negatively correlated with collagen COL9A1, gravidity with endothelial NOS and inflammatory chemokine CXCL13, and BMI with leptin and structural protein FABP4. These results provide an integrated view of epidemiological factors associated with PTB and identify biological signatures of clinical covariates affecting this disease.


Asunto(s)
Nacimiento Prematuro , Recién Nacido , Embarazo , Niño , Humanos , Femenino , Nacimiento Prematuro/epidemiología , Países en Desarrollo , Multiómica , Proteómica , Quimiocinas CC
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