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BACKGROUND: Obesity is a major health problem worldwide as it can lead to high blood pressure, heart disease, stroke, diabetes, and insulin resistance. The prevalence of overweight and obesity is increasing worldwide across different age groups. There is evidence of an inverse relationship between calcium intake and body weight. The clinical relevance of a small reduction in body weight has been questioned. However, at a population level, a small effect could mitigate the observed global trends. OBJECTIVES: To assess the effects of calcium supplementation on weight loss in individuals living with overweight or obesity. SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase, LILACS (Latin American and Caribbean Health Science Information database), and two clinical trials registries. The date of the last search of all databases (except Embase) was 10 May 2023. No language restrictions were applied. SELECTION CRITERIA: We included randomised controlled trials evaluating the effect of calcium in participants with overweight or obesity of any age or gender. We excluded studies in participants with absorption problems. We included studies of any dose with a minimum duration of two months. We included the following comparisons: calcium supplementation versus placebo, calcium-fortified food or beverage versus placebo, or calcium-fortified food or beverage versus non-calcium-fortified food or beverage. We excluded studies that evaluated the effect of calcium and vitamin D or mixed minerals compared to placebo. DATA COLLECTION AND ANALYSIS: We used standard methodological procedures expected by Cochrane. Our primary outcomes were body weight, health-related quality of life, and adverse events. Our secondary outcomes were anthropometric measures other than body weight, all-cause mortality, and morbidity. MAIN RESULTS: We found 18 studies that evaluated the effect of calcium compared to placebo or control, with a total of 1873 randomised participants (950 participants in the calcium supplementation groups and 923 in the control groups). All included studies gave oral calcium supplementation as the intervention. We did not find any studies evaluating calcium-fortified foods. We excluded 38 studies, identified four ongoing studies, and listed one study as 'awaiting classification'. Sixteen studies compared calcium supplementation to placebo; two studies compared different doses of calcium supplementation. Doses ranged from very low (0.162 g of calcium/day) to high (1.5 g of calcium/day). Most studies were performed in the USA and Iran, lasted less than six months, and included only women. Low-certainty evidence suggests that calcium supplementation compared to placebo or control may result in little to no difference in body weight (mean difference (MD) -0.15 kg, 95% confidence interval (CI) -0.55 to 0.24; P = 0.45, I2 = 46%; 17 studies, 1317 participants; low-certainty evidence). We downgraded the certainty of the evidence by two levels for risk of bias and heterogeneity. None of the included studies reported health-related quality of life, all-cause mortality, or morbidity/complications as outcomes. Only five studies assessed or reported adverse events. Low-certainty evidence suggests a low frequency of adverse events, with no clear difference between intervention and control groups. Moderate-certainty evidence shows that calcium supplementation compared to placebo or control probably results in a small reduction in body mass index (BMI) (MD -0.18 kg/m2,95% CI -0.22 to -0.13; P < 0.001, I2 = 0%; 9 studies, 731 participants) and waist circumference (MD -0.51 cm, 95% CI -0.72 to -0.29; P < 0.001, I2 = 0%; 6 studies, 273 participants). Low-certainty evidence suggests that calcium supplementation compared to placebo or control may result in a small reduction in body fat mass (MD -0.34 kg, 95% CI -0.73 to 0.05; P < 0.001, I2 = 97%; 12 studies, 812 participants). AUTHORS' CONCLUSIONS: Calcium supplementation for eight weeks to 24 months may result in little to no difference in body weight in people with overweight or obesity. The current evidence is of low certainty, due to concerns regarding risk of bias and statistical heterogeneity. We found that the degree of heterogeneity might be partly explained by calcium dosage, the presence or absence of a co-intervention, and whether an intention-to-treat analysis was pursued. While our analyses suggest that calcium supplementation may result in a small reduction in BMI, waist circumference, and fat mass, this evidence is of low to moderate certainty. Future studies could investigate the effect of calcium supplementation on lean body mass to explore if there is a change in body composition.
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Calcio de la Dieta , Suplementos Dietéticos , Obesidad , Sobrepeso , Ensayos Clínicos Controlados Aleatorios como Asunto , Pérdida de Peso , Humanos , Calcio de la Dieta/administración & dosificación , Masculino , Femenino , Adulto , Calidad de Vida , Sesgo , Alimentos Fortificados , Persona de Mediana Edad , Calcio/administración & dosificación , Calcio/uso terapéutico , Calcio/efectos adversosRESUMEN
OBJECTIVE: To simulate the impact on calcium intake - effectiveness and safety - of fortifying wheat flour with 200, 400 and 500 mg of calcium per 100 g of flour. DESIGN: Secondary analysis of cross-sectional data collected through repeated 24 h dietary recalls using the Iowa State University Intake Modelling, Assessment and Planning Program. SETTING: Urban cities in the National Health and Nutrition Survey of Argentina (ENNyS 2018-2019). PARTICIPANTS: 21 358 participants, including children, adolescents and adults. RESULTS: Most individuals in all age groups reported consuming wheat flour. The prevalence of low calcium intake was above 80 % in individuals older than 9 years. Simulating the fortification of 500 mg of calcium per 100 g of wheat flour showed that the prevalence of low calcium intake could be reduced by more than 40 percentage points in girls and women aged 19 to less than 51 years and boys and men aged 4 to less than 71 years, while it remained above 65 % in older ages. The percentages above the upper intake level remained below 1·5 % in all age groups. CONCLUSIONS: Calcium flour fortification could be further explored to improve calcium intake. Subnational simulations could be performed to identify groups that might not be reached by this strategy that could be explored in Argentina. This analysis could be used to advocate for a strategy to fortify wheat flour.
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Calcio de la Dieta , Harina , Alimentos Fortificados , Encuestas Nutricionales , Triticum , Humanos , Harina/análisis , Femenino , Calcio de la Dieta/administración & dosificación , Masculino , Adulto , Adolescente , Niño , Adulto Joven , Estudios Transversales , Preescolar , Persona de Mediana Edad , Anciano , Argentina , Dieta/estadística & datos numéricos , Dieta/métodosRESUMEN
BACKGROUND: Calcium supplementation reduces the risk of pre-eclampsia, but questions remain about the dosage to prescribe and who would benefit most. OBJECTIVES: To evaluate the effectiveness of high (≥1 g/day) and low (<1 g/day) calcium dosing for pre-eclampsia prevention, according to baseline dietary calcium, pre-eclampsia risk and co-interventions, and intervention timing. SEARCH STRATEGY: CENTRAL, PubMed, Global Index Medicus and CINAHL, from inception to 2 February 2021, clinical trial registries, reference lists and expert input (CRD42018111239). SELECTION CRITERIA: Randomised controlled trials of calcium supplementation for pre-eclampsia prevention, for women before or during pregnancy. Network meta-analysis (NMA) also included trials of different calcium doses. DATA COLLECTION AND ANALYSIS: Two independent reviewers extracted published data. The meta-analysis employed random-effects models and the NMA, a Bayesian random-effects model, to obtain direct and indirect effect estimates. MAIN RESULTS: The meta-analysis included 30 trials (N = 20 445 women), and the NMA to evaluate calcium dosage included 25 trials (N = 15 038). Calcium supplementation prevented pre-eclampsia similarly with a high dose (RR 0.49, 95% CI 0.36-0.66) or a low dose (RR 0.49, 95% CI 0.36-0.65). By NMA, high-dose (vs low-dose) calcium did not differ in effect (RR 0.79, 95% CI 0.43-1.40). Calcium was similarly effective regardless of baseline pre-eclampsia risk, vitamin D co-administration or timing of calcium initiation, but calcium was ineffective among women with adequate average baseline calcium intake. CONCLUSIONS: Low- and high-dose calcium supplementation are effective for pre-eclampsia prevention in women with low calcium intake. This has implications for population-level implementation where dietary calcium is low, and targeted implementation where average intake is adequate. TWEETABLE ABSTRACT: A network meta-analysis of 25 trials found that low-dose calcium supplementation (<1 g/day) is as effective as high-dose calcium supplementation (≥1 g/day) in halving the risk of pre-eclampsia when baseline calcium intake is low.
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Calcio de la Dieta , Preeclampsia , Teorema de Bayes , Calcio/uso terapéutico , Suplementos Dietéticos , Femenino , Humanos , Metaanálisis en Red , Preeclampsia/prevención & control , Embarazo , Atención PrenatalRESUMEN
BACKGROUND: Hypertension is a major public health problem that increases the risk of cardiovascular and kidney diseases. Several studies have shown an inverse association between calcium intake and blood pressure, as small reductions in blood pressure have been shown to produce rapid reductions in vascular disease risk even in individuals with normal blood pressure ranges. This is the first update of the review to evaluate the effect of calcium supplementation in normotensive individuals as a preventive health measure. OBJECTIVES: To assess the efficacy and safety of calcium supplementation versus placebo or control for reducing blood pressure in normotensive people and for the prevention of primary hypertension. SEARCH METHODS: The Cochrane Hypertension Information Specialist searched the following databases for randomised controlled trials up to September 2020: the Cochrane Hypertension Specialised Register, CENTRAL (2020, Issue 9), Ovid MEDLINE, Ovid Embase, the WHO International Clinical Trials Registry Platform, and the US National Institutes of Health Ongoing Trials Register, ClinicalTrials.gov. We also contacted authors of relevant papers regarding further published and unpublished work. The searches had no language restrictions. SELECTION CRITERIA: We selected trials that randomised normotensive people to dietary calcium interventions such as supplementation or food fortification versus placebo or control. We excluded quasi-random designs. The primary outcomes were hypertension (defined as blood pressure ≥ 140/90 mmHg) and blood pressure measures. DATA COLLECTION AND ANALYSIS: Two review authors independently selected trials for inclusion, abstracted the data and assessed the risks of bias. We used the GRADE approach to assess the certainty of evidence. MAIN RESULTS: The 2020 updated search identified four new trials. We included a total of 20 trials with 3512 participants, however we only included 18 for the meta-analysis with 3140 participants. None of the studies reported hypertension as a dichotomous outcome. The effect on systolic and diastolic blood pressure was: mean difference (MD) -1.37 mmHg, 95% confidence interval (CI) -2.08, -0.66; 3140 participants; 18 studies; I2 = 0%, high-certainty evidence; and MD -1.45, 95% CI -2.23, -0.67; 3039 participants; 17 studies; I2 = 45%, high-certainty evidence, respectively. The effect on systolic and diastolic blood pressure for those younger than 35 years was: MD -1.86, 95% CI -3.45, -0.27; 452 participants; eight studies; I2 = 19%, moderate-certainty evidence; MD -2.50, 95% CI -4.22, -0.79; 351 participants; seven studies ; I2 = 54%, moderate-certainty evidence, respectively. The effect on systolic and diastolic blood pressure for those 35 years or older was: MD -0.97, 95% CI -1.83, -0.10; 2688 participants; 10 studies; I2 = 0%, high-certainty evidence; MD -0.59, 95% CI -1.13, -0.06; 2688 participants; 10 studies; I2 = 0%, high-certainty evidence, respectively. The effect on systolic and diastolic blood pressure for women was: MD -1.25, 95% CI -2.53, 0.03; 1915 participants; eight studies; I2 = 0%, high-certainty evidence; MD -1.04, 95% CI -1.86, -0.22; 1915 participants; eight studies; I2 = 4%, high-certainty evidence, respectively. The effect on systolic and diastolic blood pressure for men was MD -2.14, 95% CI -3.71, -0.59; 507 participants; five studies; I2 = 8%, moderate-certainty evidence; MD -1.99, 95% CI -3.25, -0.74; 507 participants; five studies; I2 = 41%, moderate-certainty evidence, respectively. The effect was consistent in both genders regardless of baseline calcium intake. The effect on systolic blood pressure was: MD -0.02, 95% CI -2.23, 2.20; 302 participants; 3 studies; I2 = 0%, moderate-certainty evidence with doses less than 1000 mg; MD -1.05, 95% CI -1.91, -0.19; 2488 participants; 9 studies; I2 = 0%, high-certainty evidence with doses 1000 to 1500 mg; and MD -2.79, 95% CI -4.71, 0.86; 350 participants; 7 studies; I2 = 0%, moderate-certainty evidence with doses more than 1500 mg. The effect on diastolic blood pressure was: MD -0.41, 95% CI -2.07, 1.25; 201 participants; 2 studies; I2 = 0, moderate-certainty evidence; MD -2.03, 95% CI -3.44, -0.62 ; 1017 participants; 8 studies; and MD -1.35, 95% CI -2.75, -0.05; 1821 participants; 8 studies; I2 = 51%, high-certainty evidence, respectively. None of the studies reported adverse events. AUTHORS' CONCLUSIONS: An increase in calcium intake slightly reduces both systolic and diastolic blood pressure in normotensive people, particularly in young people, suggesting a role in the prevention of hypertension. The effect across multiple prespecified subgroups and a possible dose response effect reinforce this conclusion. Even small reductions in blood pressure could have important health implications for reducing vascular disease. A 2 mmHg lower systolic blood pressure is predicted to produce about 10% lower stroke mortality and about 7% lower mortality from ischaemic heart disease. There is a great need for adequately-powered clinical trials randomising young people. Subgroup analysis should involve basal calcium intake, age, sex, basal blood pressure, and body mass index. We also require assessment of side effects, optimal doses and the best strategy to improve calcium intake.
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Calcio , Hipertensión , Adolescente , Antihipertensivos/uso terapéutico , Presión Sanguínea , Suplementos Dietéticos , Femenino , Humanos , Hipertensión/tratamiento farmacológico , Hipertensión/prevención & control , MasculinoRESUMEN
OBJECTIVE: To simulate the impact - effectiveness and safety - of water fortification with different concentrations of Ca using the Intake Modelling, Assessment and Planning Program. DESIGN: This is a secondary analysis of national or sub-national dietary intake databases. SETTING AND PARTICIPANTS: Uganda, Lao People's Democratic Republic (PDR), Bangladesh, Zambia, Argentina, USA and Italy. RESULTS: We found that for dietary databases assessed from low- and middle-income countries (LMIC), the strategy of fortifying water with 500 mg of Ca/l would decrease the prevalence of low Ca intake in all age groups. We also found that this strategy would be safe as no group would present a percentage of individuals exceeding the upper limit in >2 %, except women aged 19-31 years in Lao PDR, where 6·6 % of women in this group would exceed the upper limit of Ca intake. The same strategy would lead to some groups exceeding the upper limit in USA and Italy. CONCLUSIONS: We found that for most LMIC countries, water fortified with Ca could decrease the prevalence of Ca intake inadequacy without exceeding the upper levels of Ca intake.
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Calcio , Agua , Calcio de la Dieta , Dieta , Femenino , Alimentos Fortificados/análisis , HumanosRESUMEN
Maternal mortality (MM) reflects one of the most striking global health inequalities. Global figures of MM fell significantly from 1990 to 2017. The reduction was largely due to a 70% fall in haemorrhages, and a limited (18.2%) improvement in hypertensive disorders of pregnancy (HDP). If this trend continues, by 2021 HDP will be the main cause of global MM.MM reductions due to haemorrhage is reassuring, however MM due to HDP show a more complex situation as early detection of HDP requires regular contact of pregnant women with the health system. In order to reduce MM due to HDP, population wide preventive actions such as low dose aspirin and adequate calcium intake are required, especially in areas where women have little contact with the health systems.Calcium supplementation for women with low calcium intake has reduced the risk of pre-eclampsia, with further reductions starting daily supplementation with 500 mg of calcium preconceptionally, however adherence to supplementation is limited.To reduce global inequities in calcium intake and consequently in the HDP, food fortification seem to be an attractive strategy to achieve an increase of calcium intake.
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Salud Global , Hipertensión Inducida en el Embarazo , Mortalidad Materna , Femenino , Salud Global/estadística & datos numéricos , Disparidades en el Estado de Salud , Humanos , Hipertensión Inducida en el Embarazo/mortalidad , Hipertensión Inducida en el Embarazo/prevención & control , Mortalidad Materna/tendencias , EmbarazoRESUMEN
BACKGROUND: Hypertension is a major public health problem that increases the risk of cardiovascular and kidney diseases. Several studies have shown an inverse association between calcium intake and blood pressure, as small reductions in blood pressure have been shown to produce rapid reductions in vascular disease risk even in individuals with normal blood pressure ranges. This is the first update of the review to evaluate the effect of calcium supplementation in normotensive individuals as a preventive health measure. OBJECTIVES: To assess the efficacy and safety of calcium supplementation versus placebo or control for reducing blood pressure in normotensive people and for the prevention of primary hypertension. SEARCH METHODS: The Cochrane Hypertension Information Specialist searched the following databases for randomised controlled trials up to September 2020: the Cochrane Hypertension Specialised Register, CENTRAL (2020, Issue 9), Ovid MEDLINE, Ovid Embase, the WHO International Clinical Trials Registry Platform, and the US National Institutes of Health Ongoing Trials Register, ClinicalTrials.gov. We also contacted authors of relevant papers regarding further published and unpublished work. The searches had no language restrictions. SELECTION CRITERIA: We selected trials that randomised normotensive people to dietary calcium interventions such as supplementation or food fortification versus placebo or control. We excluded quasi-random designs. The primary outcomes were hypertension (defined as blood pressure ≥ 140/90 mmHg) and blood pressure measures. DATA COLLECTION AND ANALYSIS: Two review authors independently selected trials for inclusion, abstracted the data and assessed the risks of bias. We used the GRADE approach to assess the certainty of evidence. MAIN RESULTS: The 2020 updated search identified four new trials. We included a total of 20 trials with 3512 participants, however we only included 18 for the meta-analysis with 3140 participants. None of the studies reported hypertension as a dichotomous outcome. The effect on systolic and diastolic blood pressure was: mean difference (MD) -1.37 mmHg, 95% confidence interval (CI) -2.08, -0.66; 3140 participants; 18 studies; I2 = 0%, high-certainty evidence; and MD -1.45, 95% CI -2.23, -0.67; 3039 participants; 17 studies; I2 = 45%, high-certainty evidence, respectively. The effect on systolic and diastolic blood pressure for those younger than 35 years was: MD -1.86, 95% CI -3.45, -0.27; 452 participants; eight studies; I2 = 19%, moderate-certainty evidence; MD -2.50, 95% CI -4.22, -0.79; 351 participants; seven studies ; I2 = 54%, moderate-certainty evidence, respectively. The effect on systolic and diastolic blood pressure for those 35 years or older was: MD -0.97, 95% CI -1.83, -0.10; 2688 participants; 10 studies; I2 = 0%, high-certainty evidence; MD -0.59, 95% CI -1.13, -0.06; 2688 participants; 10 studies; I2 = 0%, high-certainty evidence, respectively. The effect on systolic and diastolic blood pressure for women was: MD -1.25, 95% CI -2.53, 0.03; 1915 participants; eight studies; I2 = 0%, high-certainty evidence; MD -1.04, 95% CI -1.86, -0.22; 1915 participants; eight studies; I2 = 4%, high-certainty evidence, respectively. The effect on systolic and diastolic blood pressure for men was MD -2.14, 95% CI -3.71, -0.59; 507 participants; five studies; I2 = 8%, moderate-certainty evidence; MD -1.99, 95% CI -3.25, -0.74; 507 participants; five studies; I2 = 41%, moderate-certainty evidence, respectively. The effect was consistent in both genders regardless of baseline calcium intake. The effect on systolic blood pressure was: MD -0.02, 95% CI -2.23, 2.20; 302 participants; 3 studies; I2 = 0%, moderate-certainty evidence with doses less than 1000 mg; MD -1.05, 95% CI -1.91, -0.19; 2488 participants; 9 studies; I2 = 0%, high-certainty evidence with doses 1000 to 1500 mg; and MD -2.79, 95% CI -4.71, 0.86; 350 participants; 7 studies = 8; I2 = 0%, moderate-certainty evidence with doses more than 1500 mg. The effect on diastolic blood pressure was: MD -0.41, 95% CI -2.07, 1.25; 201 participants; 2 studies; I2 = 0, moderate-certainty evidence; MD -2.03, 95% CI -3.44, -0.62 ; 1017 participants; 8 studies; and MD -1.35, 95% CI -2.75, -0.05; 1821 participants; 8 studies; I2 = 51%, high-certainty evidence, respectively. None of the studies reported adverse events. AUTHORS' CONCLUSIONS: An increase in calcium intake slightly reduces both systolic and diastolic blood pressure in normotensive people, particularly in young people, suggesting a role in the prevention of hypertension. The effect across multiple prespecified subgroups and a possible dose response effect reinforce this conclusion. Even small reductions in blood pressure could have important health implications for reducing vascular disease. A 2 mmHg lower systolic blood pressure is predicted to produce about 10% lower stroke mortality and about 7% lower mortality from ischaemic heart disease. There is a great need for adequately-powered clinical trials randomising young people. Subgroup analysis should involve basal calcium intake, age, sex, basal blood pressure, and body mass index. We also require assessment of side effects, optimal doses and the best strategy to improve calcium intake.
Asunto(s)
Calcio , Hipertensión , Adolescente , Antihipertensivos/uso terapéutico , Presión Sanguínea , Calcio/uso terapéutico , Suplementos Dietéticos , Femenino , Humanos , Hipertensión/tratamiento farmacológico , MasculinoRESUMEN
INTRODUCTION: Though interest is growing for trials comparing planned delivery mode (vaginal delivery [VD]; cesarean section [CS]) in low-risk nulliparous women, appropriate study design is unclear. Our objective was to assess feasibility of three designs (preference trial [PCT], randomized controlled trial [RCT], partially randomized patient preference trial [PRPPT]) for a trial comparing planned delivery mode in low-risk women. METHODS: A cross-sectional survey of low-risk, nulliparous pregnant women (N = 416) and healthcare providers (N = 168) providing prenatal care and/or labor/delivery services was conducted in Argentina (2 public, 2 private hospitals). Proportion of pregnant women and providers willing to participate in each design and reasons for not participating were determined. RESULTS: Few women (< 15%) or professionals (33.3%) would participate in an RCT, though more would participate in PCTs (88% women; 65.9% professionals) or PRPPTs (44.4% public, 63.4% private sector women; 44.0% professionals). However, most women would choose vaginal delivery in the PCT and PRPPT (> 85%). Believing randomization unacceptable (RCT, PRPPT) and desiring choice of delivery mode (RCT) were women's reasons for not participating. For providers, commonly cited reasons for not participating included unacceptability of performing CS without medical indication, difficulty obtaining informed consent, discomfort enrolling patients (all designs), and violating women's right to choose (RCT). CONCLUSIONS FOR PRACTICE: Important limitations were found for each trial design evaluated. The necessity of stronger evidence regarding delivery mode in low-risk women suggests consideration of additional designs, such as a rigorously designed cohort study or an RCT within an obstetric population with equivocal CS indications.
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Cesárea/estadística & datos numéricos , Parto Obstétrico/métodos , Procedimientos Quirúrgicos Electivos , Personal de Salud/psicología , Prioridad del Paciente , Adolescente , Adulto , Argentina , Estudios de Cohortes , Estudios Transversales , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Embarazo , Medición de Riesgo , Adulto JovenRESUMEN
This article challenges the "tyranny of P-value" and promote more valuable and applicable interpretations of the results of research on health care delivery. We provide here solid arguments to retire statistical significance as the unique way to interpret results, after presenting the current state of the debate inside the scientific community. Instead, we promote reporting the much more informative confidence intervals and eventually adding exact P-values. We also provide some clues to integrate statistical and clinical significance by referring to minimal important differences and integrating the effect size of an intervention and the certainty of evidence ideally using the GRADE approach. We have argued against interpreting or reporting results as statistically significant or statistically non-significant. We recommend showing important clinical benefits with their confidence intervals in cases of point estimates compatible with results benefits and even important harms. It seems fair to report the point estimate and the more likely values along with a very clear statement of the implications of extremes of the intervals. We recommend drawing conclusions, considering the multiple factors besides P-values such as certainty of the evidence for each outcome, net benefit, economic considerations and values and preferences. We use several examples and figures to illustrate different scenarios and further suggest a wording to standardize the reporting. Several statistical measures have a role in the scientific communication of studies, but it is time to understand that there is life beyond the statistical significance. There is a great opportunity for improvement towards a more complete interpretation and to a more standardized reporting.
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Interpretación Estadística de Datos , Estadística como Asunto , Toma de Decisiones , Humanos , JurisprudenciaRESUMEN
BACKGROUND: Reducing deaths from hypertensive disorders of pregnancy is a global priority. Low dietary calcium might account for the high prevalence of pre-eclampsia and eclampsia in low-income countries. Calcium supplementation in the second half of pregnancy is known to reduce the serious consequences of pre-eclampsia; however, the effect of calcium supplementation during placentation is not known. We aimed to test the hypothesis that calcium supplementation before and in early pregnancy (up to 20 weeks' gestation) prevents the development of pre-eclampsia METHODS: We did a multicountry, parallel arm, double-blind, randomised, placebo-controlled trial in South Africa, Zimbabwe, and Argentina. Participants with previous pre-eclampsia and eclampsia received 500 mg calcium or placebo daily from enrolment prepregnancy until 20 weeks' gestation. Participants were parous women whose most recent pregnancy had been complicated by pre-eclampsia or eclampsia and who were intending to become pregnant. All participants received unblinded calcium 1·5 g daily after 20 weeks' gestation. The allocation sequence (1:1 ratio) used computer-generated random numbers in balanced blocks of variable size. The primary outcome was pre-eclampsia, defined as gestational hypertension and proteinuria. The trial is registered with the Pan-African Clinical Trials Registry, number PACTR201105000267371. The trial closed on Oct 31, 2017. FINDINGS: Between July 12, 2011, and Sept 8, 2016, we randomly allocated 1355 women to receive calcium or placebo; 331 of 678 participants in the calcium group versus 320 of 677 in the placebo group became pregnant, and 298 of 678 versus 283 of 677 had pregnancies beyond 20 weeks' gestation. Pre-eclampsia occurred in 69 (23%) of 296 participants in the calcium group versus 82 (29%) of 283 participants in the placebo group with pregnancies beyond 20 weeks' gestation (risk ratio [RR] 0·80, 95% CI 0·61-1·06; p=0·121). For participants with compliance of more than 80% from the last visit before pregnancy to 20 weeks' gestation, the pre-eclampsia risk was 30 (21%) of 144 versus 47 (32%) of 149 (RR 0·66, CI 0·44-0·98; p=0·037). There were no serious adverse effects of calcium reported. INTERPRETATION: Calcium supplementation that commenced before pregnancy until 20 weeks' gestation, compared with placebo, did not show a significant reduction in recurrent pre-eclampsia. As the trial was powered to detect a large effect size, we cannot rule out a small to moderate effect of this intervention. FUNDING: The University of British Columbia, a grantee of the Bill & Melinda Gates Foundation; UNDP-UNFPA-UNICEF-WHO-World Bank Special Programme of Research, Development and Research Training in Human Reproduction, WHO; the Argentina Fund for Horizontal Cooperation of the Argentinean Ministry of Foreign Affairs; and the Centre for Intervention Science in Maternal and Child Health.
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Calcio/administración & dosificación , Suplementos Dietéticos , Preeclampsia/prevención & control , Atención Prenatal/métodos , Adulto , Argentina , Países en Desarrollo , Método Doble Ciego , Femenino , Edad Gestacional , Salud Global , Humanos , Embarazo , Factores de Riesgo , Sudáfrica , Adulto Joven , ZimbabweRESUMEN
An amendment to this paper has been published and can be accessed via the original article.
RESUMEN
BACKGROUND: Retrospective observational studies suggest that transmission of Trypanosoma cruzi does not occur in treated women when pregnant later in life. The level of parasitemia is a known risk factor for congenital transmission. Benznidazole (BZN) is the drug of choice for preconceptional treatment to reduce parasitic load. The fear of treatment-related side effects limits the implementation of the Argentine guideline recommending BZN 60d/300 mg (or equivalent) treatment of T. cruzi seropositive women during the postpartum period to prevent transmission in a future pregnancy. A short and low dose BZN treatment might reduce major side effects and increase compliance, but its efficacy to reduce T. cruzi parasitic load compared to the standard 60d/300 mg course is not yet established. Clinical trials testing alternative BZN courses among women of reproductive age are urgently needed. METHODS AND DESIGN: We are proposing to perform a double-blinded, non-inferiority randomized controlled trial comparing a short low dose 30-day treatment with BZN 150 mg/day (30d/150 mg) vs. BZN 60d/300 mg. We will recruit not previously treated T. cruzi seropositive women with a live birth during the postpartum period in Argentina, randomize them at 6 months postpartum, and follow them up with the following specific aims: Specific aim 1: to measure the effect of BZN 30d/150 mg compared to 60d/300 mg preconceptional treatment on parasitic load measured by the frequency of positive Polymerase Chain Reaction (PCR) (primary outcome) and by real-time quantitative PCR (qPCR), immediately and 10 months after treatment. Specific aim 2: to measure the frequency of serious adverse events and/or any adverse event leading to treatment interruption. TRIAL REGISTRATION: ClinicalTrials.gov . Identifier: NCT03672487 . Registered 14 September 2018.
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Enfermedad de Chagas/tratamiento farmacológico , Nitroimidazoles/uso terapéutico , Trypanosoma cruzi/efectos de los fármacos , Argentina , Enfermedad de Chagas/diagnóstico , Femenino , Humanos , Carga de Parásitos , Periodo Posparto , Embarazo , Ensayos Clínicos Controlados Aleatorios como Asunto , Reacción en Cadena en Tiempo Real de la Polimerasa , Estudios Retrospectivos , Trypanosoma cruzi/genéticaRESUMEN
OBJECTIVE: Few data are available on cesarean delivery and operative vaginal delivery trends in low- and middle-income countries. Our objective was to analyze a prospective population-based registry including eight sites in seven low- and middle-income countries to observe trends in operative vaginal delivery versus cesarean delivery rates over time, across sites. STUDY DESIGN: A prospective population-based study, including home and facility births among women enrolled from 2010 to 2016, was performed in communities in Argentina, Democratic Republic of Congo, Guatemala, India, Kenya, Pakistan, and Zambia. Women were enrolled during pregnancy and delivery outcome data were collected. RESULTS: We analyzed 354,287 women; 4,119 (1.2%) underwent an operative vaginal delivery and 45,032 (11.2%) delivered by cesarean. Across all sites with data for 7 years, rates of operative vaginal delivery decreased from 1.6 to 0.3%, while cesarean delivery increased from 6.4 to 14.4%. Similar trends were seen when individual country data were analyzed. Operative vaginal delivery rates decreased in both hospitals and clinics, except in the hospital setting at one of the Indian sites. CONCLUSION: In low- and middle-income countries, operative vaginal delivery is becoming less utilized while cesarean delivery is becoming an increasingly common mode of delivery.
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Cesárea/tendencias , Parto Obstétrico/tendencias , África del Sur del Sahara , Asia Sudoriental , Parto Obstétrico/métodos , Países en Desarrollo , Femenino , Humanos , América Latina , Embarazo , Estudios ProspectivosRESUMEN
INTRODUCTION: The use of self-report as a strategy for collecting data on women's weight and height is widespread in both clinical practice and epidemiological studies. This study aimed to compare self-reported and directly measured weight and height among women of reproductive age. MATERIAL AND METHODS: In July 2015 we searched MEDLINE, EMBASE, COCHRANE, CINHAL, LILACS and gray literature. We included women of reproductive age (12-49 years old) independently of their weight or height at the time of the study. Women with any condition that implies regular tracking of their weight (for example, eating disorder) were excluded. Two reviewers independently selected, extracted and assessed the risk of bias of the studies. We used REVMAN 5.3 to perform the meta-analysis. Heterogeneity was assessed using the I2 statistic. RESULTS: Following eligibility assessment, 21 studies of 18 749 women met the inclusion criteria. The results of the meta-analysis showed an underestimation of weight by -0.94 kg (95% CI -1.17 to -0.71 kg; p < 0.0001; I2 = 0%) in the overall sample and an overestimation of height by 0.36 cm (95% CI 0.20-0.51; p < 0.0001; I2 = 35%) based on self-reported vs. directly measured values. CONCLUSION: This review shows that self-reported weight and height of women of reproductive age differs slightly from direct measures. We consider that the magnitude at which self-reported data over- or underestimates the real value, is negligible regarding clinical and research use.
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Estatura , Peso Corporal , Autoinforme , Adolescente , Adulto , Sesgo , Niño , Femenino , Humanos , Persona de Mediana Edad , Adulto JovenRESUMEN
BACKGROUND: Maternal nutritional status before and during pregnancy is an important contributor to pregnancy outcomes and early child health. The aim of this study was to describe the preconceptional nutritional status and dietary intake during pregnancy in high-risk women from South Africa and Zimbabwe. METHODS: This is a prospective observational study, nested to the CAP trial. Anthropometric measurements before and during pregnancy and dietary intake using 24-h recall during pregnancy were assessed. The Intake Distribution Estimation software (PC-SIDE) was used to evaluate nutrient intake adequacy taking the Estimated Average Requirement (EAR) as a cut-off point. RESULTS: Three hundred twelve women who had pre-eclampsia in their last pregnancy and delivered in hospitals from South Africa and Zimbabwe were assessed. 73.7 and 60.2% women in South Africa and Zimbabwe, respectively started their pregnancy with BMI above normal (BMI ≥ 25) whereas the prevalence of underweight was virtually non-existent. The majority of women had inadequate intakes of micronutrients. Considering food and beverage intake only, none of the micronutrients measured achieved the estimated average requirement. Around 60% of pregnant women reported taking folic acid or iron supplements in South Africa, but almost none did so in Zimbabwe. CONCLUSION: We found a high prevalence of overweight and obesity and high micronutrient intake inadequacy in pregnant women who had the previous pregnancy complicated with pre-eclampsia. The obesity figures and micronutrient inadequacy are issues of concern that need to be addressed. Pregnant women have regular contacts with the health system; these opportunities could be used to improve diet and nutrition. TRIAL REGISTRATION: PACTR201105000267371 . Registered 06 December 2010.
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Micronutrientes , Estado Nutricional , Obesidad/epidemiología , Preeclampsia/epidemiología , Adulto , Índice de Masa Corporal , Dieta , Suplementos Dietéticos , Femenino , Ácido Fólico/administración & dosificación , Ganancia de Peso Gestacional , Humanos , Hierro/administración & dosificación , Salud Materna , Embarazo , Embarazo de Alto Riesgo , Prevalencia , Estudios Prospectivos , Ensayos Clínicos Controlados Aleatorios como Asunto , Ingesta Diaria Recomendada , Sudáfrica/epidemiología , Complejo Vitamínico B/administración & dosificación , Adulto Joven , Zimbabwe/epidemiologíaRESUMEN
BACKGROUND: Understanding influences on women's preferred delivery mode is vital for planning interventions to reduce cesarean rates and for ensuring that women receive correct information. Our objectives were to: determine if sources of information influencing a pregnant woman's preferred delivery mode and knowledge of cesarean indications differ by sociodemographic characteristics; to conduct a factor analysis of items related to information sources influencing this preference; and to determine if knowledge differs by information sources influencing this preference or their underlying latent constructs. METHODS: Data from a prospective cohort study conducted in Buenos Aires was analyzed. Healthy nulliparous women aged 18-35, at >32 weeks of gestation and with live, singleton pregnancies participated. The primary research questions were evaluated using Chi-square tests, factor analysis, logistic regression, and generalized estimating equations. RESULTS: A total of 382 women participated in the study. Women of lower socioeconomic status were more influenced by people, magazines and TV/movies in their mode of delivery preferences, and had poorer knowledge of cesarean indications. Sources of influence for preferred delivery mode and factors derived in factor analysis were not associated with knowledge level when considered individually or together, or when adjusted for sociodemographic characteristics, or when accounting for clustering by the hospital sector (public or private). CONCLUSIONS: Higher socioeconomic status is associated with being less influenced by people and with better knowledge of indications for cesarean delivery. Knowledge of cesarean indications was not associated with the source of information about mode of delivery preferences.
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Cesárea/psicología , Cesárea/estadística & datos numéricos , Prioridad del Paciente/estadística & datos numéricos , Clase Social , Adolescente , Adulto , Argentina , Femenino , Conocimientos, Actitudes y Práctica en Salud , Humanos , Modelos Logísticos , Embarazo , Estudios Prospectivos , Adulto JovenRESUMEN
The Jawaharlal Nehru Medical College (JNMC) Women's and Children's Health Research Unit (WCHRU) of the Karnataka Lingayat Education (KLE) Academy of Higher Education and Research Deemed-to-be-University and its collaborators convened the '2nd International Conference on Maternal and Newborn Health -Translating Research Evidence to Practice' to address the common theme of improving maternal and newborn health in low- and middle- income countries (LMIC). This supplement, including 16 manuscripts, reflects much of the research presented at the conference, including analyses of the state of knowledge, as well as completed, ongoing and planned research in these areas conducted by the WCHRU in India together with many collaborators across high-income and LMIC. The first paper reviews maternal, fetal and neonatal mortality in low-income countries, considers their causes, as well as evidence for potential interventions to reduce mortality. A second paper addresses near miss maternal mortality. Several manuscripts address the research conducted by WCHRU and their colleagues in a multi-center research network. One study examines rates of miscarriage and medically terminated pregnancy in India and the risk factors for these occurrences. Another paper addresses stillbirth and its risk factors, both in India as well as in other LMIC. Haemorrhage and preeclampsia/eclampsia, important causes of maternal mortality, stillbirth and neonatal morbidity in LMIC, are addressed in a series of papers summarizing trials of interventions to reduce improve outcomes associated with these conditions. Poor maternal and infant nutritional status, which contribute to adverse outcomes, are addressed through papers which describe a number of important studies that the WCHRU and their colleagues have conducted to attempt to improve nutritional status. Another paper describes a study to investigate causes of stillbirth and deaths among preterm births, which will utilize new techniques to investigate the infectious causes of these deaths. Finally, the supplement addresses the process for dissemination of research results to inform public policy. Together these manuscripts represent a body of research to inform interventions to reduce maternal, fetal and newborn mortality and illustrates what a dedicated research group together with institutional support can accomplish.
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Congresos como Asunto , Salud del Lactante , Salud Materna , Investigación Biomédica Traslacional , Niño , Difusión de Innovaciones , Femenino , Humanos , India , Lactante , Mortalidad Infantil , Recién Nacido , Mortalidad Materna , EmbarazoRESUMEN
BACKGROUND: In Brazilian private hospitals, caesarean section (CS) is almost universal (88%) and is integrated into the model of birth care. A quality improvement intervention, "Adequate Birth" (PPA), based on four driving components (governance, participation of women and families, reorganisation of care, and monitoring), has been implemented to help 23 hospitals reduce their CS rate. This is a protocol designed to evaluate the implementation of PPA and its effectiveness at reducing CS as a primary outcome of birth care. METHODS: Case study of PPA intervention conducted in 2017/2018. We integrated quantitative and qualitative methods into data collection and analysis. For the quantitative stage, we selected a convenient sample of twelve hospitals. In each of these hospitals, we included 400 women. This resulted in a total sample of 4800 women. We used this sample to detect a 2.5% reduction in CS rate. We interviewed managers and puerperal women, and extracted data from hospital records. In the qualitative stage, we evaluated a subsample of eight hospitals by means of systematic observation and semi-structured interviews with managers, health professionals and women. We used specific forms for each of the four PPA driving components. Forms for managers and professionals addressed the decision-making process, implemented strategies, participatory process in strategy design, and healthcare practice. Forms for women and neonatal care addressed socio-economic, demographic and health condition; prenatal and birth care; tour of the hospital before delivery; labour expectation vs. real experience; and satisfaction with care received. We will estimate the degree of implementation of PPA strategies related to two of the four driving components: "participation of women and families" and "reorganisation of care". We will then assess its effect on CS rate and secondary outcomes for each of the twelve selected hospitals, and for the total sample. To allow for clinical, socio-demographic and obstetric characteristics in women, we will conduct multivariate analysis. Additionally, we will evaluate the influence of internal context variables (the PPA driving components "governance" and "monitoring") on the degree of implementation of the components "participation of women and families" and "reorganisation of care", by means of thematic content analysis. This analysis will include both quantitative and qualitative data. DISCUSSION: The effectiveness of quality improvement interventions that reduce CS rates requires examination. This study will identify strategies that could promote healthier births.