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1.
Birth Defects Res ; 115(2): 145-159, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36065896

RESUMO

OBJECTIVES: We describe clinical characteristics, pregnancy, and infant outcomes in pregnant people with laboratory-confirmed SARS-CoV-2 infection by trimester of infection. STUDY DESIGN: We analyzed data from the Surveillance for Emerging Threats to Mothers and Babies Network and included people with infection in 2020, with known timing of infection and pregnancy outcome. Outcomes are described by trimester of infection. Pregnancy outcomes included live birth and pregnancy loss (<20 weeks and ≥20 weeks gestation). Infant outcomes included preterm birth (<37 weeks gestation), small for gestational age, birth defects, and neonatal intensive care unit admission. Adjusted prevalence ratios (aPR) were calculated for pregnancy and selected infant outcomes by trimester of infection, controlling for demographics. RESULTS: Of 35,200 people included in this analysis, 50.8% of pregnant people had infection in the third trimester, 30.8% in the second, and 18.3% in the first. Third trimester infection was associated with a higher frequency of preterm birth compared to first or second trimester infection combined (17.8% vs. 11.8%; aPR 1.44 95% CI: 1.35-1.54). Prevalence of birth defects was 553.4/10,000 live births, with no difference by trimester of infection. CONCLUSIONS: There were no signals for increased birth defects among infants in this population relative to national baseline estimates, regardless of timing of infection. However, the prevalence of preterm birth in people with SARS-CoV-2 infection in pregnancy in our analysis was higher relative to national baseline data (10.0-10.2%), particularly among people with third trimester infection. Consequences of COVID-19 during pregnancy support recommended COVID-19 prevention strategies, including vaccination.


Assuntos
COVID-19 , Complicações Infecciosas na Gravidez , Nascimento Prematuro , Feminino , Gravidez , Lactente , Recém-Nascido , Humanos , Nascimento Prematuro/epidemiologia , SARS-CoV-2 , Resultado da Gravidez , Complicações Infecciosas na Gravidez/epidemiologia
2.
J Perinatol ; 42(10): 1328-1337, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35927486

RESUMO

OBJECTIVE: We examined the relationship between trimester of SARS-CoV-2 infection, illness severity, and risk for preterm birth. STUDY DESIGN: We analyzed data for 6336 pregnant persons with SARS-CoV-2 infection in 2020 in the United States. Risk ratios for preterm birth were calculated for illness severity, trimester of infection, and illness severity stratified by trimester of infection adjusted for age, selected underlying medical conditions, and pregnancy complications. RESULT: Pregnant persons with critical COVID-19 or asymptomatic infection, compared to mild COVID-19, in the second or third trimester were at increased risk of preterm birth. Pregnant persons with moderate-to-severe COVID-19 did not show increased risk of preterm birth in any trimester. CONCLUSION: Critical COVID-19 in the second or third trimester was associated with increased risk of preterm birth. This finding can be used to guide prevention strategies, including vaccination, and inform clinical practices for pregnant persons.


Assuntos
COVID-19 , Complicações Infecciosas na Gravidez , Nascimento Prematuro , Feminino , Humanos , Recém-Nascido , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Resultado da Gravidez , Nascimento Prematuro/epidemiologia , SARS-CoV-2 , Estados Unidos/epidemiologia
3.
Birth Defects Res ; 114(14): 805-811, 2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35906998

RESUMO

During the Centers for Disease Control and Prevention's Zika Virus Response, birth defects surveillance programs adapted to monitor birth defects potentially related to Zika virus (ZIKV) infection during pregnancy. Pregnancy outcomes occurring during January 2016 to June 2017 in 22 U.S. states and territories were used to estimate the prevalence of those brain and eye defects potentially related to ZIKV. Jurisdictions were divided into three groups: areas with widespread ZIKV transmission, areas with limited local ZIKV transmission, and areas without local ZIKV transmission. Prevalence estimates for selected brain and eye defects and microcephaly per 10,000 live births were estimated. Prevalence ratios (PRs) and 95% confidence intervals (CIs) were estimated using Poisson regression for areas with widespread and limited ZIKV transmission compared with areas without local ZIKV transmission. Defects with significantly higher prevalence in areas of widespread transmission were pooled, and PRs were calculated by quarter, comparing subsequent quarters to the first quarter (January-March 2016). Nine defects had significantly higher prevalence in areas of widespread transmission. The highest PRs were seen in intracranial calcifications (PR = 12.6, 95% CI [7.4, 21.3]), chorioretinal abnormalities (12.5 [7.1, 22.3]), brainstem abnormalities (9.3 [4.7, 18.4]), and cerebral/cortical atrophy (6.7 [4.2, 10.8]). The PR of the nine pooled defects was significantly higher in three quarters in areas with widespread transmission. The largest difference in prevalence was observed for defects consistently reported in infants with congenital ZIKV infection. Birth defects surveillance programs could consider monitoring a subset of birth defects potentially related to ZIKV in pregnancy.


Assuntos
Anormalidades Congênitas , Anormalidades do Olho , Complicações Infecciosas na Gravidez , Infecção por Zika virus , Zika virus , Encéfalo/anormalidades , Encéfalo/virologia , Anormalidades Congênitas/epidemiologia , Anormalidades Congênitas/virologia , Anormalidades do Olho/epidemiologia , Anormalidades do Olho/virologia , Feminino , Humanos , Lactente , Microcefalia , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Prevalência , Infecção por Zika virus/complicações , Infecção por Zika virus/congênito , Infecção por Zika virus/epidemiologia
4.
Paediatr Perinat Epidemiol ; 36(4): 476-484, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35437799

RESUMO

BACKGROUND: Multiple reports have described neonatal SARS-CoV-2 infection, including likely in utero transmission and early postnatal infection, but published estimates of neonatal infection range by geography and design type. OBJECTIVES: To describe maternal, pregnancy and neonatal characteristics among neonates born to people with SARS-CoV-2 infection during pregnancy by neonatal SARS-CoV-2 testing results. METHODS: Using aggregated data from the Surveillance for Emerging Threats to Mothers and Babies Network (SET-NET) describing infections from 20 January 2020 to 31 December 2020, we identified neonates who were (1) born to people who were SARS-CoV-2 positive by RT-PCR at any time during their pregnancy, and (2) tested for SARS-CoV-2 by RT-PCR during the birth hospitalisation. RESULTS: Among 28,771 neonates born to people with SARS-CoV-2 infection during pregnancy, 3816 (13%) underwent PCR testing and 138 neonates (3.6%) were PCR positive. Ninety-four per cent of neonates testing positive were born to people with infection identified ≤14 days of delivery. Neonatal SARS-CoV-2 infection was more frequent among neonates born preterm (5.7%) compared to term (3.4%). Neonates testing positive were born to both symptomatic and asymptomatic pregnant people. CONCLUSIONS: Jurisdictions reported SARS-CoV-2 RT-PCR results for only 13% of neonates known to be born to people with SARS-CoV-2 infection during pregnancy. These results provide evidence of neonatal infection identified through multi-state systematic surveillance data collection and describe characteristics of neonates with SARS-CoV-2 infection. While perinatal SARS-CoV-2 infection was uncommon among tested neonates born to people with SARS-CoV-2 infection during pregnancy, nearly all cases of tested neonatal infection occurred in pregnant people infected around the time of delivery and was more frequent among neonates born preterm. These findings support the recommendation for neonatal SARS-CoV-2 RT-PCR testing, especially for people with acute infection around the time of delivery.


Assuntos
COVID-19 , Complicações Infecciosas na Gravidez , COVID-19/diagnóstico , COVID-19/epidemiologia , Teste para COVID-19 , Feminino , Humanos , Recém-Nascido , Transmissão Vertical de Doenças Infecciosas , Gravidez , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/epidemiologia , Resultado da Gravidez/epidemiologia , SARS-CoV-2
5.
Emerg Infect Dis ; 28(4): 873-876, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35213801

RESUMO

The Surveillance for Emerging Threats to Mothers and Babies Network conducts longitudinal surveillance of pregnant persons in the United States with laboratory-confirmed severe acute respiratory syndrome coronavirus 2 infection during pregnancy. Of 6,551 infected pregnant persons in this analysis, 142 (2.2%) had positive RNA tests >90 days and up to 416 days after infection.


Assuntos
COVID-19 , Complicações Infecciosas na Gravidez , COVID-19/diagnóstico , Feminino , Humanos , Laboratórios , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , RNA Viral , SARS-CoV-2/genética , Testes Sorológicos , Estados Unidos
6.
Clin Infect Dis ; 73(Suppl 1): S17-S23, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-34021332

RESUMO

BACKGROUND: Pregnant women with coronavirus disease 2019 (COVID-19) are at increased risk for severe illness compared with nonpregnant women. Data to assess risk factors for illness severity among pregnant women with COVID-19 are limited. This study aimed to determine risk factors associated with COVID-19 illness severity among pregnant women with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. METHODS: Pregnant women with SARS-CoV-2 infection confirmed by molecular testing were reported during 29 March 2020-5 March 2021 through the Surveillance for Emerging Threats to Mothers and Babies Network (SET-NET). Criteria for illness severity (asymptomatic, mild, moderate-to-severe, or critical) were adapted from National Institutes of Health and World Health Organization criteria. Crude and adjusted risk ratios for moderate-to-severe or critical COVID-19 illness were calculated for selected demographic and clinical characteristics. RESULTS: Among 7950 pregnant women with SARS-CoV-2 infection, moderate-to-severe or critical COVID-19 illness was associated with age 25 years and older, healthcare occupation, prepregnancy obesity, chronic lung disease, chronic hypertension, and pregestational diabetes mellitus. Risk of moderate-to-severe or critical illness increased with the number of underlying medical or pregnancy-related conditions. CONCLUSIONS: Older age and having underlying medical conditions were associated with increased risk of moderate-to-severe or critical COVID-19 illness among pregnant women. This information might help pregnant women understand their risk for moderate-to-severe or critical COVID-19 illness and can inform targeted public health messaging.


Assuntos
COVID-19 , Complicações Infecciosas na Gravidez , Adulto , Idoso , Feminino , Humanos , Mães , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Gestantes , Fatores de Risco , SARS-CoV-2
7.
Matern Child Health J ; 25(2): 198-206, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33394275

RESUMO

INTRODUCTION: Public health responses often lack the infrastructure to capture the impact of public health emergencies on pregnant women and infants, with limited mechanisms for linking pregnant women with their infants nationally to monitor long-term effects. In 2019, the Centers for Disease Control and Prevention (CDC), in close collaboration with state, local, and territorial health departments, began a 5-year initiative to establish population-based mother-baby linked longitudinal surveillance, the Surveillance for Emerging Threats to Mothers and Babies Network (SET-NET). OBJECTIVES: The objective of this report is to describe an expanded surveillance approach that leverages and modernizes existing surveillance systems to address the impact of emerging health threats during pregnancy on pregnant women and their infants. METHODS: Mother-baby pairs are identified through prospective identification during pregnancy and/or identification of an infant with retrospective linking to maternal information. All data are obtained from existing data sources (e.g., electronic medical records, vital statistics, laboratory reports, and health department investigations and case reporting). RESULTS: Variables were selected for inclusion to address key surveillance questions proposed by CDC and health department subject matter experts. General variables include maternal demographics and health history, pregnancy and infant outcomes, maternal and infant laboratory results, and child health outcomes up to the second birthday. Exposure-specific modular variables are included for hepatitis C, syphilis, and Coronavirus Disease 2019 (COVID-19). The system is structured into four relational datasets (maternal, pregnancy outcomes and birth, infant/child follow-up, and laboratory testing). DISCUSSION: SET-NET provides a population-based mother-baby linked longitudinal surveillance approach and has already demonstrated rapid adaptation to COVID-19. This innovative approach leverages existing data sources and rapidly collects data and informs clinical guidance and practice. These data can help to reduce exposure risk and adverse outcomes among pregnant women and their infants, direct public health action, and strengthen public health systems.


Assuntos
Defesa Civil/métodos , Relações Mãe-Filho , Vigilância da População/métodos , Adulto , COVID-19/complicações , COVID-19/diagnóstico , Defesa Civil/instrumentação , Feminino , Hepatite C/complicações , Hepatite C/diagnóstico , Humanos , Recém-Nascido , Programas de Rastreamento/métodos , Gravidez , Sífilis/complicações , Sífilis/diagnóstico
8.
MMWR Morb Mortal Wkly Rep ; 69(44): 1635-1640, 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33151917

RESUMO

Pregnant women with coronavirus disease 2019 (COVID-19) are at increased risk for severe illness and might be at risk for preterm birth (1-3). The full impact of infection with SARS-CoV-2, the virus that causes COVID-19, in pregnancy is unknown. Public health jurisdictions report information, including pregnancy status, on confirmed and probable COVID-19 cases to CDC through the National Notifiable Diseases Surveillance System.* Through the Surveillance for Emerging Threats to Mothers and Babies Network (SET-NET), 16 jurisdictions collected supplementary information on pregnancy and infant outcomes among 5,252 women with laboratory-confirmed SARS-CoV-2 infection reported during March 29-October 14, 2020. Among 3,912 live births with known gestational age, 12.9% were preterm (<37 weeks), higher than the reported 10.2% among the general U.S. population in 2019 (4). Among 610 infants (21.3%) with reported SARS-CoV-2 test results, perinatal infection was infrequent (2.6%) and occurred primarily among infants whose mother had SARS-CoV-2 infection identified within 1 week of delivery. Because the majority of pregnant women with COVID-19 reported thus far experienced infection in the third trimester, ongoing surveillance is needed to assess effects of infections in early pregnancy, as well the longer-term outcomes of exposed infants. These findings can inform neonatal testing recommendations, clinical practice, and public health action and can be used by health care providers to counsel pregnant women on the risks of SARS-CoV-2 infection, including preterm births. Pregnant women and their household members should follow recommended infection prevention measures, including wearing a mask, social distancing, and frequent handwashing when going out or interacting with others or if there is a person within the household who has had exposure to COVID-19.†.


Assuntos
Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/diagnóstico , Pneumonia Viral/diagnóstico , Complicações Infecciosas na Gravidez/diagnóstico , Resultado da Gravidez/epidemiologia , Aborto Espontâneo/epidemiologia , Adulto , COVID-19 , Teste para COVID-19 , Técnicas de Laboratório Clínico , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/transmissão , Feminino , Humanos , Recém-Nascido , Transmissão Vertical de Doenças Infecciosas/estatística & dados numéricos , Laboratórios , Pandemias , Pneumonia Viral/epidemiologia , Pneumonia Viral/transmissão , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Nascimento Prematuro/epidemiologia , Medição de Risco , SARS-CoV-2 , Estados Unidos/epidemiologia , Adulto Jovem
9.
Viruses ; 12(2)2020 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-32033378

RESUMO

Norovirus is the most common cause of epidemic and endemic acute gastroenteritis. However, national estimates of the infection burden are challenging. This study used a nationally representative serum bank to estimate the seroprevalence to five norovirus genotypes including three GII variants: GI.1 Norwalk, GI.4, GII.3, GII.4 US95/96, GII.4 Farmington Hills, GII.4 New Orleans, and GIV.1 in the USA population (aged 16 to 49 years). Changes in seroprevalence to the three norovirus GII.4 variants between 1999 and 2000, as well as 2003 and 2004, were measured to examine the role of population immunity in the emergence of pandemic GII.4 noroviruses. The overall population-adjusted seroprevalence to any norovirus was 90.0% (1999 to 2000) and 95.9% (2003 to 2004). Seroprevalence was highest to GI.1 Norwalk, GII.3, and the three GII.4 noroviruses. Seroprevalence to GII.4 Farmington Hills increased significantly between the 1999 and 2000, as well as the 2003 and 2004, study cycles, consistent with the emergence of this pandemic strain. Seroprevalence to GII.4 New Orleans also increased over time, but to a lesser degree. Antibodies against the GIV.1 norovirus were consistently detected (population-adjusted seroprevalence 19.1% to 25.9%), with rates increasing with age. This study confirms the high burden of norovirus infection in US adults, with most adults having multiple norovirus infections over their lifetime.


Assuntos
Anticorpos Antivirais/sangue , Infecções por Caliciviridae/epidemiologia , Infecções por Caliciviridae/imunologia , Norovirus/genética , Adolescente , Adulto , Infecções por Caliciviridae/sangue , Variação Genética , Genótipo , Humanos , Pessoa de Meia-Idade , Norovirus/imunologia , RNA Viral/genética , Estudos Soroepidemiológicos , Estados Unidos/epidemiologia , Adulto Jovem
10.
MMWR Morb Mortal Wkly Rep ; 69(3): 67-71, 2020 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-31971935

RESUMO

Zika virus infection during pregnancy can cause congenital brain and eye abnormalities and is associated with neurodevelopmental abnormalities (1-3). In areas of the United States that experienced local Zika virus transmission, the prevalence of birth defects potentially related to Zika virus infection during pregnancy increased in the second half of 2016 compared with the first half (4). To update the previous report, CDC analyzed population-based surveillance data from 22 states and territories to estimate the prevalence of birth defects potentially related to Zika virus infection, regardless of laboratory evidence of or exposure to Zika virus, among pregnancies completed during January 1, 2016-June 30, 2017. Jurisdictions were categorized as those 1) with widespread local transmission of Zika virus; 2) with limited local transmission of Zika virus; and 3) without local transmission of Zika virus. Among 2,004,630 live births, 3,359 infants and fetuses with birth defects potentially related to Zika virus infection during pregnancy were identified (1.7 per 1,000 live births, 95% confidence interval [CI] = 1.6-1.7). In areas with widespread local Zika virus transmission, the prevalence of birth defects potentially related to Zika virus infection during pregnancy was significantly higher during the quarters comprising July 2016-March 2017 (July-September 2016 = 3.0; October-December 2016 = 4.0; and January-March 2017 = 5.6 per 1,000 live births) compared with the reference period (January-March 2016) (1.3 per 1,000). These findings suggest a fourfold increase (prevalence ratio [PR] = 4.1, 95% CI = 2.1-8.4) in birth defects potentially related to Zika virus in widespread local transmission areas during January-March 2017 compared with that during January-March 2016, with the highest prevalence (7.0 per 1,000 live births) in February 2017. Population-based birth defects surveillance is critical for identifying infants and fetuses with birth defects potentially related to Zika virus regardless of whether Zika virus testing was conducted, especially given the high prevalence of asymptomatic disease. These data can be used to inform follow-up care and services as well as strengthen surveillance.


Assuntos
Anormalidades Congênitas/epidemiologia , Anormalidades Congênitas/virologia , Vigilância da População , Complicações Infecciosas na Gravidez/virologia , Infecção por Zika virus/complicações , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Gravidez , Prevalência , Porto Rico/epidemiologia , Estados Unidos/epidemiologia , Ilhas Virgens Americanas/epidemiologia
11.
MMWR Morb Mortal Wkly Rep ; 67(3): 91-96, 2018 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-29370151

RESUMO

Zika virus infection during pregnancy can cause serious birth defects, including microcephaly and brain abnormalities (1). Population-based birth defects surveillance systems are critical to monitor all infants and fetuses with birth defects potentially related to Zika virus infection, regardless of known exposure or laboratory evidence of Zika virus infection during pregnancy. CDC analyzed data from 15 U.S. jurisdictions conducting population-based surveillance for birth defects potentially related to Zika virus infection.* Jurisdictions were stratified into the following three groups: those with 1) documented local transmission of Zika virus during 2016; 2) one or more cases of confirmed, symptomatic, travel-associated Zika virus disease reported to CDC per 100,000 residents; and 3) less than one case of confirmed, symptomatic, travel-associated Zika virus disease reported to CDC per 100,000 residents. A total of 2,962 infants and fetuses (3.0 per 1,000 live births; 95% confidence interval [CI] = 2.9-3.2) (2) met the case definition.† In areas with local transmission there was a non-statistically significant increase in total birth defects potentially related to Zika virus infection from 2.8 cases per 1,000 live births in the first half of 2016 to 3.0 cases in the second half (p = 0.10). However, when neural tube defects and other early brain malformations (NTDs)§ were excluded, the prevalence of birth defects strongly linked to congenital Zika virus infection increased significantly, from 2.0 cases per 1,000 live births in the first half of 2016 to 2.4 cases in the second half, an increase of 29 more cases than expected (p = 0.009). These findings underscore the importance of surveillance for birth defects potentially related to Zika virus infection and the need for continued monitoring in areas at risk for Zika.


Assuntos
Anormalidades Congênitas/epidemiologia , Anormalidades Congênitas/virologia , Vigilância da População , Infecção por Zika virus/complicações , Feminino , Humanos , Lactente , Recém-Nascido , Gravidez , Complicações Infecciosas na Gravidez/virologia , Prevalência , Porto Rico/epidemiologia , Estados Unidos/epidemiologia
12.
Sex Health ; 14(1): 18-27, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27585033

RESUMO

The trajectory of sexually transmissible infection (STI) incidence among gay and other men who have sex with men (MSM) suggests that incidence will likely remain high in the near future. STIs were hyperendemic globally among MSM in the decades preceding the HIV epidemic. Significant changes among MSM as a response to the HIV epidemic, caused STI incidence to decline, reaching historical nadirs in the mid-1990s. With the advent of antiretroviral treatment (ART), HIV-related mortality and morbidity declined significantly in that decade. Concurrently, STI incidence resurged among MSM and increased in scope and geographic magnitude. By 2000, bacterial STIs were universally resurgent among MSM, reaching or exceeding pre-HIV levels. While the evidence base necessary for assessing the burden STIs among MSM, both across time and across regions, continues to be lacking, recent progress has been made in this respect. Current epidemiology indicates a continuing and increasing trajectory of STI incidence among MSM. Yet increased reported case incidence of gonorrhoea is likely confounded by additional screening and identification of an existing burden of infection. Conversely, more MSM may be diagnosed and treated in the context of HIV care or as part of routine management of pre-exposure prophylaxis (PrEP), potentially reducing transmission. Optimistically, uptake of human papillomavirus (HPV) vaccination may lead to a near-elimination of genital warts and reductions in HPV-related cancers. Moreover, structural changes are occurring with respect to sexual minorities in social and civic life that may offer new opportunities, as well as exacerbate existing challenges, for STI prevention among MSM.


Assuntos
Bissexualidade/história , Saúde Global/história , Homossexualidade Masculina/história , Comportamento Sexual/história , Infecções Sexualmente Transmissíveis/epidemiologia , Infecções Sexualmente Transmissíveis/história , Países Desenvolvidos/história , Países em Desenvolvimento/história , Infecções por HIV/epidemiologia , Infecções por HIV/história , História do Século XX , História do Século XXI , Humanos , Incidência , Masculino
13.
PLoS One ; 11(1): e0147578, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26809066

RESUMO

To better understand the interaction of physical activity and air pollution exposure, it is important to quantify the change in ventilation rate incurred by activity. In this paper, we describe a method for estimating ventilation using easily-measured variables such as heart rate (HR), breathing rate (fB), and forced vital capacity (FVC). We recruited healthy adolescents to use a treadmill while we continuously measured HR, fB, and the tidal volume (VT) of each breath. Participants began at rest then walked and ran at increasing speed until HR was 160-180 beats per minute followed by a cool down period. The novel feature of this method is that minute ventilation ([Formula: see text]) was normalized by FVC. We used general linear mixed models with a random effect for subject and identified nine potential predictor variables that influence either [Formula: see text] or FVC. We assessed predictive performance with a five-fold cross-validation procedure. We used a brute force selection process to identify the best performing models based on cross-validation percent error, the Akaike Information Criterion and the p-value of parameter estimates. We found a two-predictor model including HR and fB to have the best predictive performance ([Formula: see text]/FVC = -4.247+0.0595HR+0.226fB, mean percent error = 8.1±29%); however, given the ubiquity of HR measurements, a one-predictor model including HR may also be useful ([Formula: see text]/FVC = -3.859+0.101HR, mean percent error = 11.3±36%).


Assuntos
Poluentes Atmosféricos/análise , Poluentes Atmosféricos/toxicidade , Adolescente , Exercício Físico/fisiologia , Feminino , Frequência Cardíaca/efeitos dos fármacos , Humanos , Masculino , Modelos Teóricos , Respiração/efeitos dos fármacos , Volume de Ventilação Pulmonar/efeitos dos fármacos
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