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1.
Psychoneuroendocrinology ; 72: 106-12, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27393907

RESUMO

Due to the rapid developmental changes that occur during the fetal period, prenatal influences can affect the developing central nervous system with lifelong consequences for physical and mental health. Glucocorticoids are one of the proposed mechanisms by which fetal programing occurs. Glucocorticoids pass through the blood-brain barrier and target receptors throughout the central nervous system. Unlike endogenous glucocorticoids, synthetic glucocorticoids readily pass through the placental barrier to reach the developing fetus. The synthetic glucocorticoid, betamethasone, is routinely given prenatally to mothers at risk for preterm delivery. Over 25% of the fetuses exposed to betamethasone will be born at term. Few studies have examined the lasting consequences of antenatal treatment of betamethasone on the regulation of the hypothalamic-pituitary-adrenal (HPA) axis. The purpose of this study is to examine whether antenatal exposure to betamethasone alters circadian cortisol regulation in children who were born full term. School-aged children prenatally treated with betamethasone and born at term (n=19, mean (SD)=8.1 (1.2) years old) were compared to children not treated with antenatal glucocorticoids (n=61, mean (SD)=8.2 (1.4) years old). To measure the circadian release of cortisol, saliva samples were collected at awakening; 30, 45, and 60min after awakening; and in the evening. Comparison children showed a typical diurnal cortisol pattern that peaked in the morning (the cortisol awakening response) and gradually decreased throughout the day. In contrast, children exposed to antenatal betamethasone lacked a cortisol awakening response and had a flatter diurnal slope (p's<0.01). These data suggest that antenatal glucocorticoid treatment may disrupt the circadian regulation of the HPA axis among children born at term. Because disrupted circadian regulation of cortisol has been linked to mental and somatic health problems, future research is needed to determine whether children exposed to antenatal synthetic glucocorticoids are at risk for poor mental and physical health.


Assuntos
Betametasona/efeitos adversos , Ritmo Circadiano , Glucocorticoides/efeitos adversos , Hidrocortisona/metabolismo , Sistema Hipotálamo-Hipofisário/metabolismo , Sistema Hipófise-Suprarrenal/metabolismo , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Criança , Feminino , Humanos , Masculino , Gravidez
2.
J Dev Orig Health Dis ; 2(4): 212-7, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25141165

RESUMO

There is evidence that fetal exposure to maternal stress is associated with adverse birth outcomes. Less is known about the association between fetal responses to a stressor and indicators of fetal maturity and developmental outcomes. The purpose of the present study was to determine whether fetal heart rate (FHR) patterns in response to a startling stimulus at ∼30 weeks of gestation were associated with gestational age at birth and birth weight. FHR was measured in 156 maternal-fetal dyads following a vibroacoustic stimulus. All pregnancies were singleton intrauterine pregnancies in English-speaking women who were primarily married, middle class, White and at least 18 years of age. Group-based trajectory modeling identified five groups of fetuses displaying distinctive longitudinal trajectories of FHR response to the startling stimulus. The FHR group trajectories were significantly associated with birth weight percentile (P < 0.01) even after controlling for estimated fetal weight at the time of assessment and parity, which are the known factors influencing birth weight (P < 0.01). Post hoc analyses indicated that two groups accounted for the association between FHR patterns and birth weight. The group (n = 23) with the lowest birth weight exhibited an immediate FHR deceleration followed by an immediate acceleration that does not recover. An FHR pattern characterized by immediate and fast acceleration to the peak and a slow discovery to baseline was associated with the highest birth weight. This is the first direct evidence showing that low birth weight and the resulting neurological consequences may have their origins in early fetal development.

3.
J Perinatol ; 29(11): 731-7, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19587690

RESUMO

OBJECTIVE: To determine whether prenatal treatment with a single course of glucocorticoids (GCs) affects size at birth among full-term infants independent of fetal size before GC administration or exposure to preterm labor (PTL). STUDY DESIGN: In all, 105 full-term infants were recruited into three study groups (30 GC treated; 60 controls matched for gestational age (GA) at birth and sex; and 15 PTL controls without GC exposure). Size of the infants was estimated before treatment using two-dimensional (2D) ultrasound and by direct measurement at birth. RESULTS: Length, weight and head circumference at birth were smaller among GC-treated infants compared with matched controls (P's<0.01), although fetal size did not differ before treatment (P's>0.2). Exposure to PTL did not account for this effect. CONCLUSIONS: Prenatal treatment with a single course of GCs was associated with a reduction in size at birth among infants born at term gestation. This effect cannot be explained by differences in fetal size before treatment or exposure to PTL.


Assuntos
Anti-Inflamatórios/efeitos adversos , Betametasona/efeitos adversos , Peso ao Nascer/efeitos dos fármacos , Síndrome do Desconforto Respiratório do Recém-Nascido/prevenção & controle , Adulto , Anti-Inflamatórios/administração & dosagem , Betametasona/administração & dosagem , Feminino , Desenvolvimento Fetal/efeitos dos fármacos , Humanos , Recém-Nascido , Masculino , Trabalho de Parto Prematuro/tratamento farmacológico , Gravidez , Ultrassonografia Pré-Natal
4.
Am J Obstet Gynecol ; 184(4): 637-42, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11262465

RESUMO

OBJECTIVE: The purpose of the study was to assess the effects of the timing of stress during pregnancy on emotional responses and birth outcome. We hypothesized that as pregnancy advanced women would become increasingly resistant to the adverse effects of stress, and so early stress would have more profound effects than later stress. STUDY DESIGN: Forty pregnant women who had experienced an earthquake during pregnancy or shortly afterward were identified. Using regression analyses we determined whether the timing of the earthquake was related to an affective response to this event and to length of gestation. RESULTS: The earthquake was rated as more stressful when it occurred early in pregnancy compared with late in pregnancy, and postpartum ratings were similar to first-trimester ratings (r (quad) =.39; P <.05). Stress experienced early in pregnancy was associated with shorter gestational length (r =.35; P <.05). CONCLUSIONS: As pregnancy advances, women become decreasingly sensitive to the effects of stress. This decrease in vulnerability may reflect increasing protection of the mother and fetus from adverse influences during pregnancy.


Assuntos
Desastres , Idade Gestacional , Complicações na Gravidez , Estresse Psicológico/complicações , Hormônio Liberador da Corticotropina/sangue , Feminino , Humanos , Gravidez , Análise de Regressão , Fatores de Risco , Fatores de Tempo
5.
Psychophysiology ; 37(4): 543-50, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10934913

RESUMO

The underuse of cardiovascular recovery as an adjunct to reactivity may stem from a lack of research on how to assess the process reliably. We explore the test-retest reliability of three simple, intuitive approaches to measuring recovery, and of a more sophisticated curve-fitting technique. Eighteen young normotensive subjects experienced three stressors twice each, with 10-min baseline, 3-min task, and 20-min recovery periods and continuous monitoring of heart rate and blood pressure. Reactivity showed moderate reliability, but the three simple approaches to measuring recovery revealed essentially none. However, the curve-fitting approach, using a three-parameter (amount, speed, and level of recovery) logistic function was reliable. This approach, capturing the inherently dynamic process of cardiovascular recovery, may allow researchers to usefully add the assessment of recovery to paradigms exploring reactivity as a risk factor for cardiovascular disease.


Assuntos
Fenômenos Fisiológicos Cardiovasculares , Hemodinâmica/fisiologia , Estresse Psicológico/fisiopatologia , Adulto , Pressão Sanguínea/fisiologia , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Modelos Teóricos , Reprodutibilidade dos Testes
6.
Psychosom Med ; 61(6): 740-3, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10593623

RESUMO

OBJECTIVE: If New York City (NYC) residents' unusually high rate of ischemic heart disease (IHD) results from chronic exposure to that city, there might also be an effect of acute exposure among visitors to NYC. We explored this possibility and also whether IHD is reduced among NYC residents dying away from the city. METHODS: Using all US death certificates for 1985-1994, we examined (correcting for age, race, and sex) IHD deaths in three groups: NYC residents who died in the city, non-NYC residents visiting the city, and NYC residents traveling out of the city. RESULTS: IHD deaths among NYC residents dying in the city were 155% of the expected proportion (p < .0001). Among visitors to the city, such deaths were 134% of the expected proportion (p < .0001). The proportion of IHD deaths among NYC residents dying out of the city was only 80% of the expected value (p <.0001). These effects are not due to nearby commuters, recent immigrants, local classification practices, or socioeconomic status, and they do not appear in other US cities. CONCLUSIONS: With both chronic and acute effects of exposure to NYC, these data are consistent with the hypothesis that the stress of NYC is linked to the high rate of IHD.


Assuntos
Exposição Ambiental/efeitos adversos , Infarto do Miocárdio/etiologia , Infarto do Miocárdio/mortalidade , Estresse Fisiológico/complicações , Estresse Psicológico/complicações , Viagem , Saúde da População Urbana/estatística & dados numéricos , Estudos Epidemiológicos , Feminino , Humanos , Masculino , Isquemia Miocárdica/etiologia , Isquemia Miocárdica/mortalidade , Cidade de Nova Iorque/epidemiologia , Fatores de Risco , Estados Unidos/epidemiologia
7.
J Psychosom Res ; 47(3): 241-54, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10576473

RESUMO

One's attitude about oneself, and the treatment one receives from others, might be affected, in some small but measurable way, by stigmatic or salutary labeling due to one's name. If names affect attitudes and attitudes affect longevity, then individuals with "positive" initials (e.g., A.C.E., V.I.P.) might live longer than those with "negative" initials (e.g., P.I.G., D.I.E.). Using California death certificates, 1969-1995, we isolated 2287 male decedents with "negative" initials and 1200 with "positive" initials. Males with positive initials live 4.48 years longer (p<0.0001), whereas males with negative initials die 2.80 years younger (p<0.0001) than matched controls. The longevity effects are smaller for females, with an increase of 3.36 years for the positive group (p<0.0001) and no decrease for the negative. Positive initials are associated with shifts away from causes of death with obvious psychological components (such as suicides and accidents), whereas negative initials are associated with shifts toward these causes. However, nearly all disease categories display an increase in longevity for the positive group and a decrease for the negative group. These findings cannot be explained by the effects of death cohort artifacts, gender, race, year of death, socioeconomic status, or parental neglect.


Assuntos
Longevidade , Nomes , Poder Psicológico , Autoimagem , Simbolismo , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Controle Interno-Externo , Masculino , Reforço Social , Identificação Social
8.
Suicide Life Threat Behav ; 29(1): 48-57, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10322620

RESUMO

This study investigated whether two widely publicized cases of deaths facilitated by physicians were followed by significant peaks in mortality. In March, 1991, Timothy Quill, MD, published a controversial editorial describing the physician-assisted suicide (PAS) of his 45-year-old, female leukemia patient. In a landmark decision in December 1990, the Missouri Supreme Court allowed removal of life support for Nancy Cruzan, a comatose accident victim. Correcting for trends and seasonal fluctuations, the authors examined: (1) U.S. leukemia mortality in the period centered on Quill's editorial, and (2) mortality from accident/coma combinations in the period centered on the Missouri Supreme Court's decision on Cruzan. Female leukemia deaths rose 11.3% above the expected rate (p < .01) just after Quill's article was published. The more closely the decedent matched Quill's patient, the greater the peak, with the largest peak (33.9%) evident for female leukemia patients in their 40s, who were long-term residents of smaller communities (p < .05). Five possible explanations for the findings were assessed, leading to the conclusion that Quill's editorial elicited an increase in mortality. The involvement of physicians in this increase is supported by analysis of the Cruzan case. This showed a mortality peak of 57% for accident/coma patients following the court decision.


Assuntos
Mortalidade/tendências , Sistema de Registros/estatística & dados numéricos , Suicídio Assistido/legislação & jurisprudência , Suicídio Assistido/psicologia , Acidentes/mortalidade , Adulto , California/epidemiologia , Coma/mortalidade , Políticas Editoriais , Feminino , Humanos , Função Jurisdicional , Leucemia/mortalidade , Masculino , Pessoa de Meia-Idade , Relações Médico-Paciente , Análise de Regressão , Estudos Retrospectivos , Estados Unidos/epidemiologia , Suspensão de Tratamento
9.
Psychosom Med ; 61(2): 234-42, 1999.
Artigo em Inglês | MEDLINE | ID: mdl-10204977

RESUMO

OBJECTIVE: Laboratory research indicates that the presence of a supportive other can reduce physiological responses to a stressor. Whether there are gender differences, either on the part of the provider or the recipient, in this social support effect is explored. Such differences might shed some light on the frequent epidemiological reports of gender differences in social support and health. METHODS: Male and female subjects gave an impromptu speech and received either standardized supportive or nonsupportive feedback from a male or female confederate. Blood pressure and heart rate were monitored continuously during baseline and speech periods. RESULTS: Speakers with a supportive female audience showed a systolic increase of 25 mm Hg over baseline. Those with a nonsupportive female audience increased 36 mm Hg. A supportive male audience led to increases of 32 mm Hg, and a nonsupportive male audience 28 mm Hg. There was no significant effect of gender of subject. CONCLUSIONS: Results indicate that social support provided by women reduced cardiovascular changes for both male and female speakers compared with presence of a nonsupportive female audience. Social support from men did not. These findings suggest a possible mechanism that might help explain the epidemiological literature on the relationship between gender, social support, and health. The findings are consistent with the notion that married men are healthier because they marry women. Women do not profit as much from marriage or suffer as much from separation, in terms of health outcomes, because the support they gain or lose is the less effective support of a man. These findings render more plausible the possibility that differences in social support might contribute to health differences, through the dampening of cardiovascular responses to stress.


Assuntos
Pressão Sanguínea/fisiologia , Frequência Cardíaca/fisiologia , Apoio Social , Estresse Psicológico/psicologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Índice de Gravidade de Doença , Fatores Sexuais , Comportamento Verbal/fisiologia
11.
Ann Behav Med ; 20(4): 317-25, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-10234426

RESUMO

One can view the "reactivity hypothesis" as having two basic forms: the individual difference or personality approach, which suggests that people who show exaggerated cardiovascular responses to stress are at increased risk of developing cardiovascular disease, and the situational or social psychological approach, which suggests that circumstances which give rise to unusually large responses are those that put people at risk of disease. Both versions rely on the generality of cardiovascular responses across situations. Evidence is presented from two studies which indicate that such generality may, however, be hard to come by. In the first study, examining the personality approach, we show that a simple change in setting dramatically attenuates the consistency of reactivity. In the second study, from the social psychological perspective, we show that subtle alterations in the situation have profound effects on group mean responses. In both cases, reactivity proved extremely sensitive to the context, suggesting that testing in arbitrary and artificial settings cannot be expected to generalize well to the real world. Instead, we argue, careful attention to psychological naturalism is essential, with the testing carefully matched to specific real-world phenomena of interest.


Assuntos
Adaptação Psicológica/fisiologia , Fenômenos Fisiológicos Cardiovasculares , Reforço Social , Apoio Social , Estresse Psicológico/fisiopatologia , Adulto , Análise de Variância , Pressão Sanguínea/fisiologia , Feminino , Humanos , Masculino , Modelos Biológicos , Desempenho Psicomotor/fisiologia
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