Pregnancy outcomes in women living with HIV and HIV-negative women in South Africa: Cohort analysis based on bias-corrected gestational age

Evaluation of quantitative bias analysis in epidemiological research: A systematic review from 2010 to mid-2023

OBJECTIVE

We aimed to demonstrate the use of quantitative bias analysis (QBA), which reveals the effects of systematic error, including confounding, misclassification and selection bias, on study results in epidemiological studies published in the period from 2010 to mid-23.

METHOD

The articles identified through a keyword search using Pubmed and Scopus were included in the study. The articles obtained from this search were eliminated according to the exclusion criteria, and the articles in which QBA analysis was applied were included in the detailed evaluation.

RESULTS

It can be said that the application of QBA analysis has gradually increased over the 13-year period. Accordingly, the number of articles in which simple is used as a method in QBA analysis is 9 (9.89%), the number of articles in which the multidimensional approach is used is 10 (10.99%), the number of articles in which the probabilistic approach is used is 60 (65.93%) and the number of articles in which the method is not specified is 12 (13.19%). The number of articles with misclassification bias model is 44 (48.35%), the number of articles with uncontrolled confounder(s) bias model is 32 (35.16%), the number of articles with selection bias model is 7 (7.69%) and the number of articles using more than one bias model is 8 (8.79%). Of the 49 (53.85%) articles in which the bias parameter source was specified, 19 (38.78%) used internal validation, 26 (53.06%) used external validation and 4 (8.16%) used educated guess, data constraints and hypothetical data. Probabilistic approach was used as a bias method in 60 (65.93%) of the articles, and mostly beta (8 [13.33%)], normal (9 [15.00%]) and uniform (8 [13.33%]) distributions were selected.

CONCLUSION

The application of QBA is rare in the literature but is increasing over time. Future researchers should include detailed analyzes such as QBA analysis to obtain inferences with higher evidence value, taking into account systematic errors.

Validation of Parent-reported Gestational Age Categories for Children Less Than 6 Years of Age

BACKGROUND

Preterm birth is an important outcome or exposure in epidemiologic research. When administrative data on measured gestational age is not available, parent-reported gestational age can be obtained from questionnaires, which is subject to potential bias. To our knowledge, few studies have assessed the validity of parent-reported gestational age categories, including commonly defined categories of preterm birth.

METHODS

We used linked data from primarily healthy children <6 years of age in TARGet Kids! in Toronto, Canada, and ICES administrative healthcare data from April 2011 to March 2020. We assessed the criterion validity of questionnaire-based parent-reported gestational age by calculating sensitivity and specificity for term (≥37 weeks), late preterm (34-36 weeks), and moderately preterm (32-33 weeks) gestational age categories, using administrative healthcare records of gestational age as the criterion standard. We conducted subgroup analyses for various parent and socioeconomic factors that may influence recall.

RESULTS

Of the 4684 participants, 97.3% correctly classified the gestational age category according to administrative healthcare data. Parent-reported gestational age sensitivity ranged from 83.7% to 98.5% and specificity ranged from 88.3% to 99.8%, depending on category. For each subgroup characteristic, sensitivity and specificity were all ≥70%. Lower educational attainment, lower family income, father reporting, ≥1 year since birth, ≥2 children, lower parent age, and reported gestational diabetes and/or hypertension were associated with slightly lower sensitivity and/or specificity.

CONCLUSIONS

In this linked cohort, parent-reported gestational age categories had high accuracy. Criterion validity varied minimally among some parent and socioeconomic factors. Our findings can inform future quantitative bias analyses.

Pregnancy and neonatal safety outcomes of timing of initiation of daily oral tenofovir disoproxil fumarate and emtricitabine pre-exposure prophylaxis for HIV prevention (CAP016): an open-label, randomised, non-inferiority trial

BACKGROUND

The safety of tenofovir disoproxil fumarate and emtricitabine as pre-exposure prophylaxis (PrEP) in pregnant women not living with HIV is uncertain. We aimed to compare pregnancy and neonatal outcomes in women exposed and not exposed to PrEP during pregnancy.

METHODS

In this single-site, open-label, randomised, non-inferiority trial in Durban, South Africa, we evaluated pregnancy and neonatal outcomes in pregnant women aged 18 years or older, not living with HIV, and at 14-28 weeks' gestation at the time of enrolment. Eligible participants were randomly assigned (1:1) using a computer-generated permuted block (block size of ten) randomisation list to immediate initiation or deferred initiation of PrEP until breastfeeding cessation. Participants in the immediate PrEP group received a monthly supply of once daily oral tenofovir disoproxil fumarate 300 mg and emtricitabine 200 mg. Participants in the deferred PrEP group received standard of care for HIV prevention. The primary outcomes were the occurrence of preterm live birth (<37 weeks gestational age) and very preterm birth (<34 weeks gestational age) determined by menstrual dating, low birthweight (<2500 g), very low birthweight (<1500 g), stillbirth (≥20 weeks gestational age), and small for gestational age (birthweight less than the tenth percentile). Post-natal safety outcomes will be reported elsewhere. We used binomial regression models to estimate risk differences and two-sided 90% CIs. Immediate PrEP was non-inferior to deferred PrEP if the upper bound of the 90% CI of the risk difference was less than the upper predefined non-inferiority margin for preterm birth (7·5%), very preterm birth (2·6%), low birthweight (5·5%), very low birthweight (1·2%), stillbirth (1·0%), and small for gestational age (3·7%). All outcomes were analysed in the intention-to-treat population. This study is registered with ClinicalTrials.gov, NCT3227731.

FINDINGS

Between Sept 25, 2017, and Dec 6, 2019, we screened 693 women, of whom 540 were randomly assigned to immediate PrEP (n=271) or deferred PrEP (n=269). The median gestational age was 19 weeks (IQR 15-23 for immediate PrEP and 16-23 for deferred PrEP). The risk difference between the immediate PrEP group and the deferred PrEP group for preterm birth was -4·7% (90% CI -10·7 to 1·2; immediate PrEP was non-inferior), for very preterm birth was 0·6% (-3·4 to 4·6; upper limit exceeded the non-inferiority margin), for low birthweight was 2·5% (-1·6 to 6·6; upper limit exceeded the non-inferiority margin), for very low birthweight was 0% (-1·4 to 1·4; upper limit exceeded the non-inferiority margin), for stillbirth was 1·2% (-1·5 to 3·8; upper limit exceeded the non-inferiority margin), and for small for gestational age was 0·9% (-1·2 to 2·9; immediate PrEP was non-inferior).

INTERPRETATION

In our study, PrEP was not associated with preterm birth or small for gestational age infants. Our data support the use of tenofovir disoproxil fumarate and emtricitabine in pregnancy and our reassuring findings can be used to allay safety concerns among pregnant women.

FUNDING

South African Medical Research Council and Gilead Sciences.

Influence of different methods for calculating gestational age at birth on prematurity and small for gestational age proportions: a systematic review with meta-analysis

BACKGROUND

Recognizing premature newborns and small-for-gestational-age (SGA) is essential for providing care and supporting public policies. This systematic review aims to identify the influence of the last menstrual period (LMP) compared to ultrasonography (USG) before 24 weeks of gestation references on prematurity and SGA proportions at birth.

METHODS

Systematic review with meta-analysis followed the recommendations of the PRISMA Statement. PubMed, BVS, LILACS, Scopus-Elsevier, Embase-Elsevier, and Web-of-Science were searched (10-30-2022). The research question was: (P) newborns, (E) USG for estimating GA, (C) LMP for estimating GA, and (O) prematurity and SGA rates for both methods. Independent reviewers screened the articles and extracted the absolute number of preterm and SGA infants, reference standards, design, countries, and bias. Prematurity was birth before 37 weeks of gestation, and SGA was the birth weight below the p10 on the growth curve. The quality of the studies was assessed using the New-Castle-Ottawa Scale. The difference between proportions estimated the size effect in a meta-analysis of prevalence.

RESULTS

Among the 642 articles, 20 were included for data extraction and synthesis. The prematurity proportions ranged from 1.8 to 33.6% by USG and varied from 3.4 to 16.5% by the LMP. The pooled risk difference of prematurity proportions revealed an overestimation of the preterm birth of 2% in favor of LMP, with low certainty: 0.02 (95%CI: 0.01 to 0.03); I² 97%). Subgroup analysis of USG biometry (eight articles) showed homogeneity for a null risk difference between prematurity proportions when crown-rump length was the reference: 0.00 (95%CI: -0.001 to 0.000; I²: 0%); for biparietal diameter, risk difference was 0.00 (95%CI: -0.001 to 0.000; I²: 41%). Only one report showed the SGA proportions of 32% by the USG and 38% by the LMP.

CONCLUSIONS

LMP-based GA, compared to a USG reference, has little or no effect on prematurity proportions considering the high heterogeneity among studies. Few data (one study) remained unclear the influence of such references on SGA proportions. Results reinforced the importance of qualified GA to mitigate the impact on perinatal statistics.

TRIAL REGISTRATION

Registration number PROSPERO: CRD42020184646.

Epidemiologia do HIV em gestantes e sua relação com o período da pandemia de COVID-19

RESUMO Objetivo: Analisar, à luz da Teoria Social Ecológica, a evolução dos casos notificados de HIV na gestação em um estado brasileiro e sua relação com o início da pandemia de COVID-19. Método: Estudo retrospectivo, com amostra composta por todas as notificações de HIV gestacional do estado do Ceará - Brasil no período de 2017 a 2021, na plataforma IntegraSUS. A coleta de dados foi realizada em janeiro de 2022. As variáveis analisadas foram organizadas de acordo com os níveis teóricos: macrossistema, exossistema, mesossistema e microssistema. Resultados: Foram registrados 1.173 casos de HIV em gestantes. Ao comparar o período pré e pós-pandemia, observou-se redução da taxa de detecção da doença (de 231 para 122,67 gestantes) e 1,82 vezes mais chances de as mulheres não usarem antirretrovirais no parto após o início da pandemia. Houve redução de 55% de partos vaginais e de 39% de cesarianas das mulheres com diagnóstico de HIV após o início da pandemia. Conclusão A pandemia de COVID-19 causou impacto epidemiológico e assistencial, levando a uma redução do número de notificações e taxa de detecção de gestantes que vivem com HIV no estado do Ceará. Logo, reforça-se a necessidade de assegurar a cobertura de atenção à saúde, com ações de diagnóstico precoce, garantia de tratamento e uma assistência pré-natal de qualidade.

Epidemiology of HIV in pregnant women and its relationship with the period of the COVID-19 pandemic

OBJECTIVE

To analyze, in the light of the Social Ecological Theory, the progression of reported cases of HIV during pregnancy in a Brazilian state and their relationship with the onset of the COVID-19 pandemic.

METHOD

Retrospective study, with a sample consisting of all reports of gestational HIV in the state of Ceará - Brazil from 2017 to 2021, on the IntegraSUS platform. Data collection was carried out in January 2022. The analyzed variables were organized according to the theoretical levels: macrosystem, exosystem, mesosystem, and microsystem.

RESULTS

A total of 1,173 cases of HIV in pregnant women were recorded. When comparing the pre- and post-pandemic period, a reduction in the disease detection rate (from 231 to 122.67 pregnant women) was observed, as well as 1.82 times more chances of women not using antiretrovirals during childbirth after the start of the pandemic. There was a 55% reduction in vaginal births and 39% in cesarean sections among women diagnosed with HIV after the start of the pandemic.

CONCLUSION

The COVID-19 pandemic had an epidemiological and care impact, leading to a reduction in the number of notifications and in the detection rate of pregnant women living with HIV in the state of Ceará. Therefore, the need to ensure health care coverage is emphasized, with early diagnosis actions, guaranteed treatment, and quality prenatal care.