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Study Objectives: The mechanisms linking short sleep duration to cardiovascular disease (CVD) are poorly understood. Emerging evidence suggests that endothelial dysregulation may lie along the causal pathway linking sleep duration to cardiovascular risk, although current evidence in humans is based on cross-sectional studies. Our objective was to evaluate the prospective association between objectively assessed sleep duration and clinical indices of endothelial health. Methods: A total of 141 medically healthy adults underwent an overnight laboratory sleep study when they were between the ages of 21 and 60 years. Total sleep time was objectively assessed by polysomnography at study entry. Endothelial health, including brachial artery diameter (BAD) and flow-mediated dilation (FMD), was measured 18.9 ± 4.6 years later. Medical health and psychiatric status were assessed at both time points. Approximately half of the sample had a lifetime history of major depressive disorder. Results: In univariate analyses, shorter sleep duration was associated with increased BAD (ß = -0.24, p = .004) and decreased FMD (ß = 0.17, p = .042). BAD, but not FMD, remained significantly associated with sleep duration after adjusting for sex, age, body mass index (BMI), smoking, diabetes, hypertension, and lifetime history of major depressive disorder (MDD) at T2. The association between sleep duration and BAD was stronger than the association between BAD and an aggregate measure of CVD risk including three or more of the following risk factors: male sex, age ≥ 65 years, smoker, BMI ≥ 30, diabetes, hypertension, and MDD. Conclusions: Objectively assessed short sleep duration was prospectively associated with increased BAD over a 12- to 30-year period.
Assuntos
Artéria Braquial/patologia , Artéria Braquial/fisiologia , Endotélio Vascular/patologia , Endotélio Vascular/fisiologia , Sono/fisiologia , Adulto , Índice de Massa Corporal , Artéria Braquial/fisiopatologia , Transtorno Depressivo Maior/complicações , Diabetes Mellitus , Endotélio Vascular/fisiopatologia , Feminino , Voluntários Saudáveis , Humanos , Hipertensão/complicações , Masculino , Pessoa de Meia-Idade , Polissonografia , Estudos Prospectivos , Fatores de Risco , Fatores Sexuais , Fumar , Fatores de Tempo , Adulto JovemRESUMO
STUDY OBJECTIVES: Evaluate whether levels of upsetting life events measured over a 9-y period prospectively predict subjective and objective sleep outcomes in midlife women. DESIGN: Prospective cohort study. SETTING: Four sites across the United States. PARTICIPANTS: 330 women (46-57 y of age) enrolled in the Study of Women's Health Across the Nation (SWAN) Sleep Study. INTERVENTIONS: N/A. MEASUREMENTS AND RESULTS: Upsetting life events were assessed annually for up to 9 y. Trajectory analysis applied to life events data quantitatively identified three distinct chronic stress groups: low stress, moderate stress, and high stress. Sleep was assessed by self-report and in-home polysomnography (PSG) during the ninth year of the study. Multivariate analyses tested the prospective association between chronic stress group and sleep, adjusting for race, baseline sleep complaints, marital status, body mass index, symptoms of depression, and acute life events at the time of the Sleep Study. Women characterized by high chronic stress had lower subjective sleep quality, were more likely to report insomnia, and exhibited increased PSG-assessed wake after sleep onset (WASO) relative to women with low to moderate chronic stress profiles. The effect of chronic stress group on WASO persisted in the subsample of participants without baseline sleep complaints. CONCLUSIONS: Chronic stress is prospectively associated with sleep disturbance in midlife women, even after adjusting for acute stressors at the time of the sleep study and other factors known to disrupt sleep. These results are consistent with current models of stress that emphasize the cumulative effect of stressors on health over time.
Assuntos
Inquéritos Epidemiológicos , Transtornos do Sono-Vigília/epidemiologia , Transtornos do Sono-Vigília/fisiopatologia , Sono/fisiologia , Estresse Psicológico/epidemiologia , Estresse Psicológico/fisiopatologia , Saúde da Mulher , Doença Crônica , Estudos de Coortes , Feminino , Humanos , Pessoa de Meia-Idade , Polissonografia , Estudos Prospectivos , Autorrelato , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Distúrbios do Início e da Manutenção do Sono/fisiopatologia , Distúrbios do Início e da Manutenção do Sono/psicologia , Transtornos do Sono-Vigília/psicologia , Estresse Psicológico/psicologia , Estados Unidos/epidemiologiaRESUMO
A Poisson regression model with an offset assumes a constant baseline rate after accounting for measured covariates, which may lead to biased estimates of coefficients in an inhomogeneous Poisson process. To correctly estimate the effect of time-dependent covariates, we propose a Poisson change-point regression model with an offset that allows a time-varying baseline rate. When the nonconstant pattern of a log baseline rate is modeled with a nonparametric step function, the resulting semi-parametric model involves a model component of varying dimension and thus requires a sophisticated varying-dimensional inference to obtain correct estimates of model parameters of fixed dimension. To fit the proposed varying-dimensional model, we devise a state-of-the-art MCMC-type algorithm based on partial collapse. The proposed model and methods are used to investigate an association between daily homicide rates in Cali, Colombia and policies that restrict the hours during which the legal sale of alcoholic beverages is permitted. While simultaneously identifying the latent changes in the baseline homicide rate which correspond to the incidence of sociopolitical events, we explore the effect of policies governing the sale of alcohol on homicide rates and seek a policy that balances the economic and cultural dependencies on alcohol sales to the health of the public.
RESUMO
BACKGROUND: Cali, Colombia, has a high incidence of interpersonal violence deaths. Various alcohol control policies have been implemented to reduce alcohol-related problems. The objective of this study was to determine whether different alcohol control policies were associated with changes in the incidence rate of homicides. METHODS: Ecologic study conducted during 2004-08 using a time-series design. Policies were implemented with variations in hours of restriction of sales and consumption of alcohol. Most restrictive policies prohibited alcohol between 2 a.m. and 10 a.m. for 446 non-consecutive days. Moderately restrictive policies prohibited alcohol between 3 a.m. and 10 a.m. for 1277 non-consecutive days. Lax policies prohibited alcohol between 4 a.m. and 10 a.m. for 104 non-consecutive days. In conditional autoregressive negative binomial regressions, rates of homicides and unintentional injury deaths (excluding traffic events) were compared between different periods of days when different policies were in effect. RESULTS: There was an increased risk of homicides in periods when the moderately restrictive policies were in effect compared with periods when the most restrictive policies were in effect [incidence rate ratio (IRR) 1.15, 90% confidence interval (CI) 1.05-1.26, P = 0.012], and there was an even higher risk of homicides in periods when the lax policies were in effect compared with periods when the most restrictive policies were in effect (IRR 1.42, 90% CI 1.26-1.61, P < 0.001). Less restrictive policies were not associated with increased risk of unintentional injury deaths. CONCLUSION: Extended hours of sales and consumption of alcohol were associated with increased risk of homicides. Strong restrictions on alcohol availability could reduce the incidence of interpersonal violence events in communities where homicides are high.