RESUMEN
Obstructive sleep apnoea syndrome (OSAS) often coexists in patients with chronic obstructive pulmonary disease (COPD). The present prospective cohort study tested the effect of OSAS treatment with continuous positive airway pressure (CPAP) on the survival of hypoxaemic COPD patients. It was hypothesised that CPAP treatment would be associated with higher survival in patients with moderate-to-severe OSAS and hypoxaemic COPD receiving long-term oxygen therapy (LTOT). Prospective study participants attended two outpatient advanced lung disease LTOT clinics in São Paulo, Brazil, between January 1996 and July 2006. Of 603 hypoxaemic COPD patients receiving LTOT, 95 were diagnosed with moderate-to-severe OSAS. Of this OSAS group, 61 (64%) patients accepted and were adherent to CPAP treatment, and 34 did not accept or were not adherent and were considered not treated. The 5-yr survival estimate was 71% (95% confidence interval 53-83%) and 26% (12-43%) in the CPAP-treated and nontreated groups, respectively (p<0.01). After adjusting for several confounders, patients treated with CPAP showed a significantly lower risk of death (hazard ratio of death versus nontreated 0.19 (0.08-0.48)). The present study found that CPAP treatment was associated with higher survival in patients with moderate-to-severe OSAS and hypoxaemic COPD receiving LTOT.
Asunto(s)
Presión de las Vías Aéreas Positiva Contínua , Hipoxia/mortalidad , Hipoxia/terapia , Terapia por Inhalación de Oxígeno , Enfermedad Pulmonar Obstructiva Crónica/mortalidad , Enfermedad Pulmonar Obstructiva Crónica/terapia , Síndromes de la Apnea del Sueño/mortalidad , Síndromes de la Apnea del Sueño/terapia , Anciano , Femenino , Humanos , Hipoxia/complicaciones , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Enfermedad Pulmonar Obstructiva Crónica/complicaciones , Índice de Severidad de la Enfermedad , Síndromes de la Apnea del Sueño/complicaciones , Tasa de SupervivenciaRESUMEN
Published guidelines recommend spirometry to accurately diagnose chronic obstructive pulmonary disease (COPD). However, even spirometry-based COPD prevalence estimates can vary widely. We compared properties of several spirometry-based COPD definitions using data from the international Burden of Obstructive Lung Disease (BOLD)study. 14 sites recruited population-based samples of adults aged > or =40 yrs. Procedures included standardised questionnaires and post-bronchodilator spirometry. 10,001 individuals provided usable data. Use of the lower limit of normal (LLN) forced expiratory volume in 1 s (FEV(1)) to forced vital capacity (FVC) ratio reduced the age-related increases in COPD prevalence that are seen among healthy never-smokers when using the fixed ratio criterion (FEV(1)/FVC <0.7) recommended by the Global Initiative for Chronic Obstructive Lung Disease. The added requirement of an FEV(1) either <80% predicted or below the LLN further reduced age-related increases and also led to the least site-to-site variability in prevalence estimates after adjusting for potential confounders. Use of the FEV(1)/FEV(6) ratio in place of the FEV(1)/FVC yielded similar prevalence estimates. Use of the FEV(1)/FVCAsunto(s)
Volumen Espiratorio Forzado
, Enfermedad Pulmonar Obstructiva Crónica/diagnóstico
, Enfermedad Pulmonar Obstructiva Crónica/fisiopatología
, Espirometría
, Capacidad Vital
, Adulto
, Anciano
, Estudios de Cohortes
, Femenino
, Humanos
, Masculino
, Persona de Mediana Edad
, Guías de Práctica Clínica como Asunto
, Valor Predictivo de las Pruebas
, Prevalencia
, Enfermedad Pulmonar Obstructiva Crónica/epidemiología
, Reproducibilidad de los Resultados
, Estudios Retrospectivos
, Encuestas y Cuestionarios
RESUMEN
BACKGROUND: The association of tobacco smoke with the prevalence of asthma and rhinitis has not been well-characterized in adolescents. METHODS: As part of the International Study of Asthma and Allergies in Childhood (ISAAC), we conducted a cross-sectional survey of 3000 adolescents aged 13-14 years in northern Argentina. Data included questions about asthma and rhinitis symptoms and about parental and personal smoking. Logistic regression and Pearson chi(2) statistics were used to estimate these associations. RESULTS: Over 13% of respondents described themselves as current smokers, and half indicated that at least one parent smoked at home. Active smoking was associated with both asthma (OR 1.83, 95%CI 1.42-2.35) and rhinitis (OR 1.61, 95%CI 1.33-1.92) in unadjusted analysis. These associations persisted after adjusting for parental smoking status, mother's educational level and sex. Boys were significantly less likely than girls to report current asthma or rhinitis. CONCLUSIONS: Active and passive smoking are both risk factors for asthma and rhinitis in adolescents. Assuming that some children with asthma never started smoking due to symptoms, then the true risk could be higher than reported here. These results reinforce the need to develop better strategies for primary and secondary prevention of tobacco exposure in children.
Asunto(s)
Asma/epidemiología , Rinitis/epidemiología , Fumar/epidemiología , Adolescente , Argentina/epidemiología , Estudios Transversales , Femenino , Humanos , Modelos Logísticos , Masculino , Prevalencia , Prevención Primaria , Factores de Riesgo , Prevención del Hábito de Fumar , Contaminación por Humo de Tabaco/estadística & datos numéricosRESUMEN
BACKGROUND: Chronic obstructive pulmonary disease (COPD) is underdiagnosed. One barrier to diagnosis is the limited availability of spirometry testing, but in adults at risk for COPD, a normal pre-bronchodilator (pre-BD) peak expiratory flow (PEF) may rule out clinically significant COPD. OBJECTIVE: To identify post-BD airway obstruction using data from 13 708 individuals aged >or=40 years from the PLATINO and BOLD studies. METHODS: We evaluated different cut-off points of pre-BD. The PEF was obtained from a diagnostic-quality spirometer (not a mechanical PEF meter). At least one of the following COPD risk factors was present in 77% of the subjects: chronic respiratory symptoms; exposure to tobacco smoke, biomass smoke or dust in the workplace; or a previous diagnosis of asthma, COPD, emphysema or chronic bronchitis. RESULTS: Although the positive predictive value was low as expected, a pre-BD PEF of >or=70% predicted effectively ruled out Stages III and IV COPD of the Global Initiative for Chronic Obstructive Lung Disease. Among those with at least one risk factor, only 12% would require confirmatory spirometry using this criterion. CONCLUSIONS: Adding PEF measurement to a screening questionnaire may rule out severe to very severe COPD without the need for pre- and post-BD spirometry testing. Confirmation is needed from a study using inexpensive PEF meters or pocket spirometers with a staged screening protocol.
Asunto(s)
Ápice del Flujo Espiratorio , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Espirometría , Anciano , Obstrucción de las Vías Aéreas/tratamiento farmacológico , Broncodilatadores/uso terapéutico , Femenino , Volumen Espiratorio Forzado , Humanos , Masculino , Persona de Mediana Edad , Enfermedad Pulmonar Obstructiva Crónica/tratamiento farmacológico , Sensibilidad y Especificidad , Espirometría/estadística & datos numéricosRESUMEN
UNLABELLED: This study used in-depth interviews and focus groups to evaluate osteoporosis care after a fracture. Patients (eligible women aged 67 who sustained a clinical fracture(s)), clinicians, and staff stated that an outreach program facilitated osteoporosis care management, but more-tailored education and support and increased participation of orthopedic specialists appear necessary. INTRODUCTION: Osteoporosis treatment reduces fracture risk, but screening and treatment are underutilized, even after a fracture has occurred. This study evaluated key stakeholder perspectives about the care of osteoporosis after a fracture. METHODS: Participants were from a nonprofit health maintenance organization in the United States: eligible women members aged 67 or older who sustained a clinical fracture(s) (n = 10), quality and other health care managers (n = 20), primary care providers (n = 9), and orthopedic clinicians and staff (n = 28); total n = 67. In-depth interviews and focus groups elicited participant perspectives on an outreach program to patients and clinicians and other facilitators and barriers to care. Interviews and focus group sessions were transcribed and content-analyzed. RESULTS: Patients, clinicians, and staff stated that outreach facilitated osteoporosis care management, but important patient barriers remained. Patient knowledge gaps and fatalism were common. Providers stated that management needed to begin earlier, and longer-term patient support was necessary to address adherence. Orthopedic clinicians and staff expressed lack of confidence in their osteoporosis management but willingness to encourage treatment. CONCLUSIONS: Although an outreach program assisted with the management of osteoporosis after a fracture, more-tailored education and support and increased participation of orthopedic specialists appear necessary to maximize osteoporosis management.
Asunto(s)
Fracturas Óseas/etiología , Osteoporosis Posmenopáusica/tratamiento farmacológico , Calidad de la Atención de Salud , Anciano , Densidad Ósea , Conservadores de la Densidad Ósea/uso terapéutico , Atención a la Salud/normas , Femenino , Grupos Focales , Fracturas Óseas/prevención & control , Conocimientos, Actitudes y Práctica en Salud , Humanos , Entrevistas como Asunto , Osteoporosis Posmenopáusica/complicaciones , Atención Primaria de Salud/normas , Evaluación de Programas y Proyectos de Salud , Estados UnidosRESUMEN
SETTING: Burden of Obstructive Lung Disease (BOLD) Initiative sites worldwide. OBJECTIVE: To measure the prevalence of chronic obstructive pulmonary disease (COPD) and its risk factors, investigate variation in prevalence across countries and develop standardized methods that can be used in industrialized and developing countries. DESIGN: Non-institutionalized adults aged > or =40 years were recruited using population-based sampling plans. Each site targeted a minimum of 600 participants (300 women, 300 men), who filled out questionnaires and performed spirometry before and after administration of 200 mug salbutamol using standardized methods. Random effects meta-analysis models were used to estimate pooled prevalence estimates and risk factor effects and to test for heterogeneity across sites and sex. RESULTS: Data published from 12 sites (n = 8775) showed that the estimated population prevalence of COPD (Global Initiative for Chronic Obstructive Lung Disease [GOLD] Stage II and higher) was 10.1 +/- SE = 4.8% overall (11.8 +/- 7.9% for men and 8.5 +/- 5.8% for women). Prevalence increased with age and pack-years of smoking, but other less understood risk factors, such as biomass heating and cooking exposures, occupational exposures and tuberculosis, also contribute to the location-specific variations in disease prevalence that BOLD is finding. CONCLUSION: BOLD has estimated the social and economic burden of COPD in 12 countries to date. BOLD and the Proyecto Latinoamericano de Investigación en Obstrucción Pulmonar (the PLATINO study) are developing a growing database of COPD prevalence. Cigarette smoking and age are the most important COPD risk factors, but other risk factors should also be explored.
Asunto(s)
Costo de Enfermedad , Países Desarrollados/estadística & datos numéricos , Países en Desarrollo/estadística & datos numéricos , Enfermedad Pulmonar Obstructiva Crónica/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Factores de Riesgo , EspirometríaRESUMEN
Biofilm formation and cell-cell sensing by the pioneer dental plaque colonizer Streptococcus gordonii are dependent upon arginine. This study aimed to identify genetic factors linking arginine-dependent responses and biofilm formation in S. gordonii. Isogenic mutants disrupted in genes required for the biosynthesis or catabolism of arginine, or for arginine-dependent gene regulation, were screened for their ability to form biofilms in a static culture model. Biofilm formation by a knockout mutant of arcR, encoding an arginine-dependent regulator of transcription, was reduced to < 50% that of the wild-type whereas other strains were unaffected. Complementation of S. gordonii ∆arcR with a plasmid-borne copy of arcR restored the ability to develop biofilms. By DNA microarray analysis, 25 genes were differentially regulated in S. gordonii ∆arcR compared with wild-type under arginine-replete conditions including eight genes encoding components of phosphotransferase systems for sugar uptake. By contrast, disruption of argR or ahrC genes, which encode paralogous arginine-dependent regulators, each resulted in significant changes in the expression of more than 100 genes. Disruption of a gene encoding a putative extracellular protein that was strongly regulated in S. gordonii ∆arcR had a minor impact on biofilm formation. We hypothesize that genes regulated by ArcR form a critical pathway linking arginine sensing to biofilm formation in S. gordonii. Further elucidation of this pathway may provide new targets for the control of dental plaque formation by inhibiting biofilm formation by a key pioneer colonizer of tooth surfaces.
Asunto(s)
Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Biopelículas/crecimiento & desarrollo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Placa Dental/microbiología , Streptococcus gordonii/genética , Streptococcus gordonii/metabolismo , Arginina/metabolismo , ADN Bacteriano/genética , Perfilación de la Expresión Génica , Regulación Bacteriana de la Expresión Génica , Técnicas de Inactivación de Genes , Genes Bacterianos/genética , Fosfotransferasas/genética , Fosfotransferasas/metabolismo , Regulón/genética , Proteínas Represoras/genética , Proteínas Represoras/metabolismo , Transactivadores/genéticaRESUMEN
Morphogenesis of the rod-shaped Escherichia coli is determined by controlled growth of an exoskeleton made of murein (peptidoglycan). Recent insights in the growth strategy of the stress-bearing murein sacculus has contributed to our understanding of how the required concerted action of murein polymerizing and hydrolyzing enzymes is achieved. The proteins involved are coordinated by the formation of multienzyme complexes. In this review, we summarize the recent results on murein structure and metabolism. On the basis of these findings, we present a model that explains maintenance of the specific rod shape of E. coli.
Asunto(s)
Escherichia coli/citología , División Celular , Escherichia coli/enzimología , Escherichia coli/crecimiento & desarrollo , Morfogénesis , Peptidoglicano/metabolismoRESUMEN
Ambulatory blood pressure monitoring (ABPM) is commonly used in clinical trials. Yet, its ability to detect blood pressure (BP) change in comparison to multiple office-based measurements has received limited attention. We recorded ambulatory and five daily pairs of random zero (RZ) BPs pre- and post-intervention on 321 adult participants in the multicentre Dietary Approaches to Stop Hypertension trial. Treatment effect estimates measured by ambulatory monitoring were similar to those measured by RZ and did not differ significantly for waking vs 24-h ambulatory measurements. For systolic BP, the standard deviations of change in mean 24-h ambulatory BP (8.0 mmHg among hypertensives and 6.0 mmHg among nonhypertensives) were comparable to or lower than the corresponding standard deviations of change in RZ-BP based on five daily readings (8.9 and 5.9 mmHg). The standard deviations of change for mean waking ambulatory BP (8.7 and 6.7 mmHg) were comparable to those obtained using three to four daily RZ readings. Results for diastolic BP were qualitatively similar. Ambulatory monitoring was more efficient (ie, a smaller sample size could detect a given BP change) than three to four sets of daily RZ readings and required fewer clinic visits. The average of 33 ambulatory BP readings during the waking hours had an efficiency comparable to that from the mean of four daily pairs of RZ-BPs. Participants readily accepted the ABPM devices, and their use requires less staff training. ABPM provides a useful alternative to RZ-BP measurements in clinical trials.
Asunto(s)
Monitoreo Ambulatorio de la Presión Arterial , Hipertensión/fisiopatología , Visita a Consultorio Médico , Adulto , Ritmo Circadiano/fisiología , Protocolos Clínicos , Femenino , Humanos , Hipertensión/dietoterapia , Masculino , Reproducibilidad de los Resultados , Estudios RetrospectivosRESUMEN
Recommendations for control of high blood pressure (BP) emphasize lifestyle modification, including weight loss, reduced sodium intake, increased physical activity, and limited alcohol consumption. The Dietary Approaches to Stop Hypertension (DASH) dietary pattern also lowers BP. The PREMIER randomized trial tested multicomponent lifestyle interventions on BP in demographic and clinical subgroups. Participants with above-optimal BP through stage 1 hypertension were randomized to an Advice Only group or one of two behavioural interventions that implement established recommendations (Est) or established recommendations plus DASH diet (Est plus DASH). The primary outcome was change in systolic BP at 6 months. The study population was 810 individuals with an average age of 50 years, 62% women, 34% African American (AA), 95% overweight/obese, and 38% hypertensive. Participants in all the three groups made lifestyle changes. Mean net reductions in systolic (S) BP in the Est intervention were 1.2 mmHg in AA women, 6.0 in AA men, 4.5 in non-AA women, and 4.2 in non-AA men. The mean effects of the Est Plus DASH intervention were 2.1, 4.6, 4.2, and 5.7 mmHg in the four race-sex subgroups, respectively. BP changes were consistently greater in hypertensives than in nonhypertensives, although interaction tests were nonsignificant. The Est intervention caused statistically significant BP reductions in individuals over and under age 50. The Est Plus DASH intervention lowered BP in both age groups, and significantly more so in older individuals. In conclusion, diverse groups of people can adopt multiple lifestyle changes that can lead to improved BP control and reduced CVD risk.
Asunto(s)
Dieta Hiposódica , Consejo Dirigido , Hipertensión/terapia , Estilo de Vida , Educación del Paciente como Asunto , Adulto , Negro o Afroamericano , Factores de Edad , Femenino , Conductas Relacionadas con la Salud , Humanos , Masculino , Persona de Mediana Edad , Factores Sexuales , Pérdida de PesoRESUMEN
BACKGROUND: Measures of patient satisfaction or dissatisfaction with treatment are increasingly being used as indicators of quality of care. As these measures become more widely used, it is important to know if patient dissatisfaction is associated with important processes or outcomes of medical care. METHODS: Survey of patient-reported asthma management issues using the Asthma Therapy Assessment Questionnaire in a large health maintenance organization in the Pacific Northwest. Associations between patient dissatisfaction with asthma treatment and patient-reported measures of asthma control, patient-provider communication, and belief in asthma medications (self-efficacy) were examined. RESULTS: Of the 5181 adult members with asthma enrolled in the health maintenance organization, 30% indicated dissatisfaction with current treatment. Dissatisfaction was higher among patients with a higher number of asthma control problems, patient-provider communication problems, or belief in medication problems (eg, failure to believe their medications are useful and inability to take asthma medications as directed). The odds of dissatisfaction with treatment were 2.8 (95% confidence interval [CI], 2.4-3.3; P<.001) for asthma control problems, 2.0 (95% CI, 1.6-2.6; P<.001) for communication problems, and 8.0 (95% CI, 6.7-9.5; P<.001) for belief in medication problems compared with patients without these perceived problems. CONCLUSION: Patient dissatisfaction with treatment may be related to important asthma disease management issues.
Asunto(s)
Asma/terapia , Satisfacción del Paciente , Adulto , Anciano , Asma/prevención & control , Femenino , Humanos , Masculino , Persona de Mediana Edad , Relaciones Médico-PacienteRESUMEN
OBJECTIVE: To examine the differences in medical management and quality of life between patients with asthma who receive their primary asthma care from allergists and those who receive their care from generalists in a large health maintenance organization (HMO). METHODS: We conducted a cross-sectional study of patients with asthma in a large HMO (Kaiser Permanente, Northwest Region, Portland, Ore). Participants were 392 individuals aged 15 through 55 years with physician-diagnosed asthma, taking antiasthma medications, reporting current asthma symptoms, and receiving asthma care from an allergist or from a generalist. Primary outcomes include characteristics of asthma, health care utilization, and quality of life. RESULTS: Patients cared for by allergists tended to have more severe asthma than those cared for by generalists (P < .01). The allergists' patients tended to be older (38.6 +/- 9.6 years vs 35.7 +/- 12.6 years, P < .01), more atopic (91% vs 78%, P < .01), and more likely to report perennial (rather than seasonal) asthma (26% vs 36%, P < .04) than the generalists' patients. Patients receiving their primary asthma care from an allergist were considerably more likely than generalists' patients to report using inhaled anti-inflammatory agents (P < .01), oral steroids (P < .01), and regular (daily) breathing medications to control their asthma (P < .01). Allergists' patients were more likely to have asthma exacerbations treated in a clinic setting rather than an emergency department (P < .01). Furthermore, allergists' patients reported significantly improved quality of life as measured by several dimensions of the SF-36 scale (physical functioning, role emotional, bodily pain, and general health; P < .05). CONCLUSIONS: These findings suggest that specialist care of asthma is of benefit for patients with asthma in a large HMO. Specifically, the allergists' patients conformed more closely to national asthma management guidelines and reported better quality of life than did the generalists' patients.
Asunto(s)
Alergia e Inmunología , Asma/tratamiento farmacológico , Medicina Familiar y Comunitaria , Sistemas Prepagos de Salud/estadística & datos numéricos , Pautas de la Práctica en Medicina/estadística & datos numéricos , Calidad de Vida , Adolescente , Adulto , Antiasmáticos/uso terapéutico , Asma/epidemiología , Asma/psicología , Estudios Transversales , Utilización de Medicamentos/estadística & datos numéricos , Femenino , Sistemas Prepagos de Salud/normas , Hospitalización/estadística & datos numéricos , Humanos , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Oregon , Evaluación de Resultado en la Atención de Salud , Guías de Práctica Clínica como AsuntoRESUMEN
OBJECTIVE: To determine the effects of dietary patterns on blood pressure in subgroups. METHODS: Dietary Approaches to Stop Hypertension (DASH) was a randomized controlled feeding study conducted at 4 academic medical centers. Participants were 459 adults with untreated systolic blood pressure less than 160 mm Hg and diastolic blood pressure 80 to 95 mm Hg. For 3 weeks, participants were fed a "control" diet. They were then randomized to 8 weeks of (1) control diet; (2) a diet rich in fruits and vegetables; or (3) a combination diet rich in fruits, vegetables, and low-fat dairy foods, and reduced in saturated fat, total fat, and cholesterol (the DASH combination diet). Weight and salt intake were held constant. Change in diastolic blood pressure was the primary outcome variable, and systolic blood pressure a secondary outcome. Subgroups analyzed included race, sex, age, body mass index, years of education, income, physical activity, alcohol intake, and hypertension status. RESULTS: The combination diet significantly lowered systolic blood pressure in all subgroups (P<.008), and significantly lowered diastolic blood pressure (P<.01) in all but 2 subgroups. The fruits-and-vegetables diet also reduced blood pressure in the same subgroups, but to a lesser extent. The combination diet lowered systolic blood pressure significantly more in African Americans (6.8 mm Hg) than in whites (3.0 mm Hg), and in hypertensive subjects (11.4 mm Hg) than in nonhypertensive subjects (3.4 mm Hg) (P<.05 for both interactions). CONCLUSIONS: The DASH combination diet, without sodium reduction or weight loss, significantly lowered blood pressure in virtually all subgroups examined, and was particularly effective in African Americans and those with hypertension. The DASH combination diet may be an effective strategy for preventing and treating hypertension in a broad cross section of the population, including segments of the population at highest risk for blood pressure-related cardiovascular disease.
Asunto(s)
Hipertensión/dietoterapia , Adulto , Negro o Afroamericano , Población Negra , Femenino , Frutas , Hispánicos o Latinos , Humanos , Hipertensión/etnología , Hipertensión/prevención & control , Masculino , Persona de Mediana Edad , Verduras , Población BlancaRESUMEN
Weight is strongly associated with bone mineral density (BMD), but the mechanism of this effect is not well understood. Weight, height, hip-waist ratio, elbow breadth, adiposity, and BMD were measured in 6705 older women participating in the Study of Osteoporotic Fractures. Adiposity was measured by bioelectric impedance and BMD by single-photon (proximal and distal radius and calcaneus) and dual-energy x-ray absorptiometry (lumbar spine and proximal femur). Age-adjusted associations between weight and BMD were robust at all sites (R2 = 5.9-20.4%), but the addition of other anthropometric variables to the model only marginally improved the association. Adiposity explained a substantial fraction of the effect of weight on BMD, particularly at weight-bearing sites (36-62%). On the other hand, weight explained virtually all the variability of adiposity on BMD at weight-bearing sites (81-100%). At the radial measurement sites, adiposity had more substantial independent contributions. Weight did not seem to influence the relationship between BMD and age. In sum, at weight bearing-sites, the preponderance of the effect of weight on BMD is a direct result of mass effects rather than adiposity, whereas at non-weight-bearing sites, adiposity exerts more important effects, potentially mediated by metabolic factors.
Asunto(s)
Tejido Adiposo/anatomía & histología , Composición Corporal , Estatura , Peso Corporal , Densidad Ósea , Anciano , Constitución Corporal , Índice de Masa Corporal , Estudios de Cohortes , Impedancia Eléctrica , Femenino , Predicción , HumanosRESUMEN
We measured ambulatory blood pressure (ABP) in 354 participants in the Dietary Approaches to Stop Hypertension (DASH) Trial to determine the effect of dietary treatment on ABP (24-hour, day and night) and to assess participants' acceptance of and compliance with the ABP monitoring (ABPM) technique. After a 3-week run-in period on a control "typical" American diet, subjects (diastolic blood pressure [BP], 80 to 95 mm Hg; systolic BP, <160 mm Hg; mean age, 45 years) were randomly assigned to 1 of 3 diets for an 8-week intervention period: a continuation of the control diet; a diet rich in fruits and vegetables; and a "combination" diet that emphasized fruits, vegetables, and low-fat dairy products. We measured ABP at the end of the run-in and intervention periods. Both the fruit/vegetable and combination diets lowered 24-hour ABP significantly compared with the control diet (P<0. 0001 for systolic and diastolic pressures on both diets: control diet, -0.2/+0.1 mm Hg; fruit/vegetable diet, -3.2/-1.9 mm Hg; combination diet, -4.6/-2. 6 mm Hg). The combination diet lowered pressure during both day and night. Hypertensive subjects had a significantly greater response than normotensives to the combination diet (24-hour ABP, -10.1/-5.5 versus -2.3/-1.6 mm Hg, respectively). After correction for the control diet responses, the magnitude of BP lowering was not significantly different whether measured by ABPM or random-zero sphygmomanometry. Participant acceptance of ABPM was excellent: only 1 participant refused to wear the ABP monitor, and 7 subjects (2%) provided incomplete recordings. These results demonstrate that the DASH combination diet provides significant round-the-clock reduction in BP, especially in hypertensive participants.
Asunto(s)
Hipertensión/dietoterapia , Adulto , Presión Sanguínea , Monitoreo Ambulatorio de la Presión Arterial , Ritmo Circadiano , Estudios de Cohortes , Femenino , Humanos , Hipertensión/fisiopatología , Masculino , Persona de Mediana Edad , Cooperación del Paciente , Resultado del TratamientoRESUMEN
Following the 1980 Mount St. Helens volcanic eruption, psychiatric reactions were studied in the disaster area and in a control community. Using the new criterion-based diagnostic method for psychiatric epidemiologic research, the Diagnostic Interview Schedule, the authors found a significant prevalence of disaster-related psychiatric disorders. These Mount St. Helens disorders included depression, generalized anxiety, and posttraumatic stress reaction. There was a progressive "dose-response" relationship in the comparison of control, low-exposure, and high-exposure groups. The dose-response pattern occurred among both the bereaved and the property-loss victims.
Asunto(s)
Desastres , Trastornos Mentales/diagnóstico , Adolescente , Adulto , Anciano , Trastornos de Ansiedad/diagnóstico , Trastornos de Ansiedad/epidemiología , Trastornos de Ansiedad/etiología , Muerte , Trastorno Depresivo/diagnóstico , Trastorno Depresivo/epidemiología , Trastorno Depresivo/etiología , Femenino , Pesar , Estado de Salud , Humanos , Acontecimientos que Cambian la Vida , Masculino , Trastornos Mentales/epidemiología , Trastornos Mentales/etiología , Persona de Mediana Edad , Escalas de Valoración Psiquiátrica , Psicometría , Factores Sexuales , Trastornos por Estrés Postraumático/diagnóstico , Trastornos por Estrés Postraumático/epidemiología , Trastornos por Estrés Postraumático/etiología , WashingtónRESUMEN
BACKGROUND: Effects of diet on blood lipids are best known in white men, and effects of type of carbohydrate on triacylglycerol concentrations are not well defined. OBJECTIVE: Our goal was to determine the effects of diet on plasma lipids, focusing on subgroups by sex, race, and baseline lipid concentrations. DESIGN: This was a randomized controlled outpatient feeding trial conducted in 4 field centers. The subjects were 436 participants of the Dietary Approaches to Stop Hypertension (DASH) Trial [mean age: 44.6 y; 60% African American; baseline total cholesterol: < or = 6.7 mmol/L (< or = 260 mg/dL)]. The intervention consisted of 8 wk of a control diet, a diet increased in fruit and vegetables, or a diet increased in fruit, vegetables, and low-fat dairy products and reduced in saturated fat, total fat, and cholesterol (DASH diet), during which time subjects remained weight stable. The main outcome measures were fasting total cholesterol, LDL cholesterol, HDL cholesterol, and triacylglycerol. RESULTS: Relative to the control diet, the DASH diet resulted in lower total (-0.35 mmol/L, or -13.7 mg/dL), LDL- (-0.28 mmol/L, or -10.7 mg/dL), and HDL- (-0.09 mmol/L, or -3.7 mg/dL) cholesterol concentrations (all P < 0.0001), without significant effects on triacylglycerol. The net reductions in total and LDL cholesterol in men were greater than those in women by 0.27 mmol/L, or 10.3 mg/dL (P = 0.052), and by 0.29 mmol/L, or 11.2 mg/dL (P < 0.02), respectively. Changes in lipids did not differ significantly by race or baseline lipid concentrations, except for HDL, which decreased more in participants with higher baseline HDL-cholesterol concentrations than in those with lower baseline HDL-cholesterol concentrations. The fruit and vegetable diet produced few significant lipid changes. CONCLUSIONS: The DASH diet is likely to reduce coronary heart disease risk. The possible opposing effect on coronary heart disease risk of HDL reduction needs further study.
Asunto(s)
Grasas de la Dieta/administración & dosificación , Hipertensión/sangre , Hipertensión/dietoterapia , Lípidos/sangre , Triglicéridos/sangre , Adulto , Anciano , Estudios de Cohortes , Enfermedad Coronaria/sangre , Enfermedad Coronaria/etiología , Productos Lácteos , Femenino , Frutas , Humanos , Hipertensión/fisiopatología , Masculino , Persona de Mediana Edad , Factores de Riesgo , VerdurasRESUMEN
PURPOSE: To evaluate patterns of lung function in healthy, working Chinese men and women in different geographic areas of the People's Republic of China (PRC). METHODS: We conducted lung function tests on 2926 asymptomatic, never smoking Chinese men and women aged 35-56 years residing in or around Beijing and Guangzhou. Within each of these locations, separate urban and rural samples were recruited. RESULTS: Age and height adjusted lung function was greater in Beijing than in Guangzhou, and within each city for residents of rural vs. urban areas. Among women, estimated rates of lung aging were greater in Beijing than in Guangzhou, and in urban vs. rural areas. Both FEV(1) and FVC exhibited a curvilinear association with body mass index. CONCLUSIONS: Lung function data from this largely working cohort exhibited marked geographic and urban-rural differences in this never smoking, adult Chinese cohort. Such variation is not uncommon and may reflect differences in body size, diet, and environmental and occupational exposures across these different settings. Caution should be used in applying published reference equations to populations from different parts of the PRC.
Asunto(s)
Pulmón/fisiología , Exposición Profesional , Adulto , Factores de Edad , Constitución Corporal , China/epidemiología , Estudios de Cohortes , Dieta , Femenino , Geografía , Humanos , Masculino , Persona de Mediana Edad , Valores de Referencia , Pruebas de Función Respiratoria , Población Rural , Factores Sexuales , Población UrbanaRESUMEN
Epidemiologic studies have found that dietary patterns characterized by high intakes of certain minerals and fiber are associated with low blood pressure. Dietary Approaches to Stop Hypertension (DASH) is a multicenter, randomized, controlled-feeding trial designed to test the effects on blood pressure of two such dietary patterns consumed for 8 weeks. The two experimental diets will be compared with each other and with a control dietary pattern that is relatively low in potassium, magnesium, calcium, and fiber, and has a fat and protein profile mirroring current consumption. The first experimental diet, arguably termed "ideal," is high in fruits, vegetables, whole cereal products, low-fat dairy products, fish, chicken, and lean meats designed to be low in saturated fat and cholesterol; moderately high in protein; and high in minerals and fiber. The second experimental diet tests the effect of fruits and vegetables alone. Its potassium, magnesium, and dietary fiber content will be at the same high levels as the ideal dietary pattern, while its fat, protein, and calcium content will resemble that of the control dietary pattern. The study population will consist of 456 healthy men and women, aged 22 years or older, with systolic blood pressure less than 160 mm Hg and diastolic blood pressure 80 to 95 mm Hg. African-American and other minority groups will comprise 67% of the population. Participants will eat one of the three dietary patterns. The DASH trial has unique features. First, dietary patterns rather than single nutrients are being tested. Second, all food for the experimental diets is provided to the participants using a standardized multicenter protocol. Because the dietary patterns are constructed with commonly consumed food items, the results, if positive, may be conveniently implemented in dietary recommendations to the general public.
Asunto(s)
Presión Sanguínea , Hipertensión/dietoterapia , Hipertensión/prevención & control , Proyectos de Investigación , Adulto , Población Negra , Grasas de la Dieta/administración & dosificación , Fibras de la Dieta/administración & dosificación , Proteínas en la Dieta/administración & dosificación , Femenino , Humanos , Hipertensión/etnología , Masculino , Población BlancaRESUMEN
Adjustment for initial value may yield misleading results when comparing change over time in two populations. This paper presents a methodology for correcting for the effects of regression to the mean when change over time is regressed on standardized initial level. The results are used to examine the bias introduced by failing to correct for the effects of regression to the mean in the two sample problem. We also examine the implications of adjusting for initial value in certain observational studies. When group assignment is known to be related to initial value, we argue that this adjustment procedure is inappropriate. The results are illustrated using data from a longitudinal study of lung function decline.