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1.
J Frailty Aging ; 12(4): 267-276, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38008976

RESUMEN

BACKGROUND: Frailty is a multidimensional state of increased vulnerability. Frail patients are at increased risk for poor surgical outcomes. Prior research demonstrates that rehabilitation strategies deployed after surgery improve outcomes by building strength. OBJECTIVES: Examine the feasibility and impact of a novel, multi-faceted prehabilitation intervention for frail patients before surgery. DESIGN: Single arm clinical trial. SETTING: Veterans Affairs hospital. PARTICIPANTS: Patients preparing for major abdominal, urological, thoracic, or cardiac surgery with frailty identified as a Risk Analysis Index≥30. INTERVENTION: Prehabilitation started in a supervised setting to establish safety and then transitioned to home-based exercise with weekly telephone coaching by exercise physiologists. Prehabilitation included (a)strength and coordination training; (b)respiratory muscle training (IMT); (c)aerobic conditioning; and (d)nutritional coaching and supplementation. Prehabilitation length was tailored to the 4-6 week time lag typically preceding each participant's normally scheduled surgery. MEASUREMENTS: Functional performance and patient surveys were assessed at baseline, every other week during prehabilitation, and then 30 and 90 days after surgery. Within-person changes were estimated using linear mixed models. RESULTS: 43 patients completed baseline assessments; 36(84%) completed a median 5(range 3-10) weeks of prehabilitation before surgery; 32(74%) were retained through 90-day follow-up. Baseline function was relatively low. Exercise logs show participants completed 94% of supervised exercise, 78% of prescribed IMT and 74% of home-based exercise. Between baseline and day of surgery, timed-up-and-go decreased 2.3 seconds, gait speed increased 0.1 meters/second, six-minute walk test increased 41.7 meters, and the time to complete 5 chair rises decreased 1.6 seconds(all P≤0.007). Maximum and mean inspiratory and expiratory pressures increased 4.5, 7.3, 14.1 and 13.5 centimeters of water, respectively(all P≤0.041). CONCLUSIONS: Prehabilitation is feasible before major surgery and achieves clinically meaningful improvements in functional performance that may impact postoperative outcomes and recovery. These data support rationale for a larger trial powered to detect differences in postoperative outcomes.


Asunto(s)
Terapia por Ejercicio , Fragilidad , Humanos , Terapia por Ejercicio/métodos , Rendimiento Físico Funcional , Complicaciones Posoperatorias , Cuidados Preoperatorios/métodos , Ejercicio Preoperatorio
2.
Osteoarthritis Cartilage ; 27(7): 1018-1025, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30716537

RESUMEN

OBJECTIVE: Determine modifiable social and psychological health factors that are associated with use of oral opioid and non-opioid medications for OA. METHODS: Patients were categorized based on use of the following oral medications: opioids (with/without other oral analgesic treatments), non-opioid analgesics, and no oral analgesic treatment. We used multinomial logistic regression models to estimate adjusted relative risk ratios (RRRs) of using an opioid or a non-opioid analgesic (vs. no oral analgesic treatment), comparing patients by levels of social support (Medical Outcomes Study scale), health literacy ("How confident are you filling out medical forms by yourself?"), and depressive symptoms (Patient Health Questionnaire-8). Models were adjusted for demographic and clinical characteristics. RESULTS: In this sample (mean age 64.2 years, 23.6% women), 30.6% (n = 110) reported taking opioid analgesics for OA, 54.2% (n = 195) reported non-opioid use, and 15.3% (n = 55) reported no oral analgesic use. Opioid users had lower mean social support scores (10.0 vs 10.5 vs 11.9, P = 0.007) and were more likely to have moderate-severe depressive symptoms (42.7% vs 24.1% vs 14.5%, P < 0.001). Health literacy did not differ by treatment group type. Having moderate-severe depression was associated with higher risk of opioid analgesic use compared to no oral analgesic use (RRR 2.96, 95%CI 1.08-8.07) when adjusted for sociodemographic and clinical factors. Neither social support nor health literacy was associated with opioid or non-opioid oral analgesic use in fully adjusted models. CONCLUSIONS: Knee OA patients with more severe depression symptoms, compared to those without, were more likely to report using opioid analgesics for OA.


Asunto(s)
Analgésicos no Narcóticos/uso terapéutico , Analgésicos Opioides/uso terapéutico , Osteoartritis de la Rodilla/tratamiento farmacológico , Osteoartritis de la Rodilla/psicología , Manejo del Dolor/métodos , Administración Oral , Anciano , Análisis de Varianza , Antiinflamatorios no Esteroideos/uso terapéutico , Estudios Transversales , Femenino , Estudios de Seguimiento , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Psicología , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
3.
Stat Med ; 36(29): 4677-4691, 2017 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-28833382

RESUMEN

Modeling of correlated biomarkers jointly has been shown to improve the efficiency of parameter estimates, leading to better clinical decisions. In this paper, we employ a joint modeling approach to a unique diabetes dataset, where blood glucose (continuous) and urine glucose (ordinal) measures of disease severity for diabetes are known to be correlated. The postulated joint model assumes that the outcomes are from distributions that are in the exponential family and hence modeled as multivariate generalized linear mixed effects model associated through correlated and/or shared random effects. The Markov chain Monte Carlo Bayesian approach is used to approximate posterior distribution and draw inference on the parameters. This proposed methodology provides a flexible framework to account for the hierarchical structure of the highly unbalanced data as well as the association between the 2 outcomes. The results indicate improved efficiency of parameter estimates when blood glucose and urine glucose are modeled jointly. Moreover, the simulation studies show that estimates obtained from the joint model are consistently less biased and more efficient than those in the separate models.


Asunto(s)
Teorema de Bayes , Modelos Lineales , Análisis Multivariante , Índice de Severidad de la Enfermedad , Adulto , Anciano , Biomarcadores/sangre , Biomarcadores/orina , Glucemia/análisis , Simulación por Computador , Diabetes Mellitus/sangre , Diabetes Mellitus/orina , Femenino , Hospitales , Humanos , Masculino , Cadenas de Markov , Persona de Mediana Edad , Método de Montecarlo , Sistema de Registros , Uganda , Adulto Joven
4.
Regul Toxicol Pharmacol ; 70(1): 203-13, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25010378

RESUMEN

ß-Chloroprene (2-chloro-1,3-butadiene, CD) is used in the manufacture of polychloroprene rubber. Chronic inhalation studies have demonstrated that CD is carcinogenic in B6C3F1 mice and Fischer 344 rats. However, epidemiological studies do not provide compelling evidence for an increased risk of mortality from total cancers of the lung. Differences between the responses observed in animals and humans may be related to differences in toxicokinetics, the metabolism and detoxification of potentially active metabolites, as well as species differences in sensitivity. The purpose of this study was to develop and apply a novel method that combines the results from available physiologically based kinetic (PBK) models for chloroprene with a statistical maximum likelihood approach to test commonality of low-dose risk across species. This method allows for the combined evaluation of human and animal cancer study results to evaluate the difference between predicted risks using both external and internal dose metrics. The method applied to mouse and human CD data supports the hypothesis that a PBK-based metric reconciles the differences in mouse and human low-dose risk estimates and further suggests that, after PBK metric exposure adjustment, humans are equally or less sensitive than mice to low levels of CD exposure.


Asunto(s)
Carcinógenos/toxicidad , Cloropreno/toxicidad , Neoplasias/inducido químicamente , Medición de Riesgo/métodos , Animales , Carcinógenos/administración & dosificación , Carcinógenos/farmacocinética , Cloropreno/administración & dosificación , Cloropreno/farmacocinética , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Funciones de Verosimilitud , Masculino , Ratones , Neoplasias/epidemiología , Ratas , Ratas Endogámicas F344 , Especificidad de la Especie
5.
Psychol Med ; 39(1): 55-64, 2009 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18377672

RESUMEN

BACKGROUND: Little is known about factors that predict first lifetime episodes of major depression in middle-aged women. It is not known whether health-related factors and life stress pose more or less of a risk to the onset of clinical depression than does the menopausal transition. METHOD: The Structured Clinical Interview for DSM-IV Axis I Disorders (SCID) was used to assess diagnoses of lifetime, annual and current major depression in a community-based sample of premenopausal or early perimenopausal African American and White women. Menstrual cycle characteristics, psychosocial and health-related factors, and blood samples for assay of reproductive hormones were obtained annually. Two hundred and sixty-six women without a history of major depression at baseline constituted the cohort for the current analyses. RESULTS: Over 7 years of follow-up, 42 (15.8%) women met criteria for a diagnosis of major depression. Frequent vasomotor symptoms (VMS; hot flashes and/or night sweats) (HR 2.14, p=0.03) were a significant predictor of major depression in univariate analyses. After simultaneous adjustment for multiple predictors in Cox proportional hazards analyses, frequent VMS were no longer significant; lifetime history of an anxiety disorder (HR 2.20, p=0.02) and role limitations due to physical health (HR 1.88, p=0.07) at baseline and a very stressful life event (HR 2.25, p=0.04) prior to depression onset predicted a first episode of major depression. CONCLUSIONS: Both earlier (e.g. history of anxiety disorders) and more proximal factors (e.g. life stress) may be more important than VMS in contributing to a first episode of major depression during midlife.


Asunto(s)
Envejecimiento/psicología , Trastorno Depresivo Mayor/epidemiología , Trastorno Depresivo Mayor/psicología , Adulto , Negro o Afroamericano/psicología , Negro o Afroamericano/estadística & datos numéricos , Trastornos de Ansiedad/epidemiología , Trastornos de Ansiedad/psicología , Índice de Masa Corporal , Estudios de Cohortes , Femenino , Hormona Folículo Estimulante/sangre , Estudios de Seguimiento , Estado de Salud , Humanos , Entrevista Psicológica/métodos , Estudios Longitudinales , Menopausia/sangre , Menopausia/psicología , Persona de Mediana Edad , Pennsylvania/epidemiología , Valor Predictivo de las Pruebas , Factores de Riesgo , Estrés Psicológico/epidemiología , Estrés Psicológico/psicología , Trastornos Relacionados con Sustancias/epidemiología , Trastornos Relacionados con Sustancias/psicología , Población Blanca/psicología , Población Blanca/estadística & datos numéricos , Salud de la Mujer
6.
Int J Obes Relat Metab Disord ; 28(8): 1026-32, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15159768

RESUMEN

OBJECTIVE: To determine whether dietary intake and physical activity contribute to obesity in women with polycystic ovary syndrome (PCOS). DESIGN: Case-control study. SUBJECTS: A total of 84 cases and 79 neighborhood controls of similar age. MEASUREMENTS: Fasting insulin, body mass index (BMI, kg/m2), waist/hip ratio, Block Food Frequency Questionnaire, Paffenbarger Physical Activity Questionnaire. RESULTS: Although women with PCOS had a higher BMI than control women, an overall comparison of women with and without PCOS showed no significant difference in dietary intake. However, stratification by BMI revealed that lean women with PCOS reported significantly lower energy intake than lean women without PCOS. CONCLUSION: Differences in dietary intake and physical activity alone are not sufficient to explain differences in weight between women with and without PCOS. Further research is necessary to determine the relative contributions of lifestyle factors and metabolism to obesity in PCOS.


Asunto(s)
Ingestión de Energía , Ejercicio Físico , Obesidad/complicaciones , Síndrome del Ovario Poliquístico/complicaciones , Adulto , Constitución Corporal , Índice de Masa Corporal , Estudios de Casos y Controles , Femenino , Humanos , Insulina/sangre , Modelos Lineales , Persona de Mediana Edad , Obesidad/metabolismo , Síndrome del Ovario Poliquístico/metabolismo
7.
Occup Environ Med ; 61(3): 270-4, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-14985523

RESUMEN

AIMS: To determine cause specific mortality in a cohort of 2266 chemical workers exposed to benzene in various manufacturing processes after 1935. METHODS: The cohort has accumulated over 80 000 person-years of observation; about 70% of the workers were followed for more than 30 years since first exposure. RESULTS: Mortality from non-malignant diseases of the blood was increased (SMR 2.17, 95% CI 0.87 to 4.48), and correlated with duration of benzene exposure, although risk had decreased from the previous investigation of this cohort. The risk for leukaemia was slightly above background (SMR 1.14, obs 12, 95% CI 0.59 to 1.99) but has also decreased since the earlier study of this cohort. SMRs for acute non-lymphocytic leukaemia (ANLL), chronic lymphatic leukaemia, and non-Hodgkin's lymphoma were 1.11, 0.42, and 1.06 respectively. There was evidence of a weak trend of increasing SMRs for leukaemia and possibly ANLL with increasing low-level cumulative exposure but not with other measures. CONCLUSION: Leukaemia and ANLL results were consistent with the mildly increased risk estimates from lower exposure subgroups of the Pliofilm cohort.


Asunto(s)
Benceno/toxicidad , Leucemia/inducido químicamente , Linfoma/inducido químicamente , Enfermedades Profesionales/inducido químicamente , Exposición Profesional/efectos adversos , Adulto , Anciano , Industria Química , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Leucemia/mortalidad , Linfoma/mortalidad , Masculino , Persona de Mediana Edad , Países Bajos/epidemiología , Enfermedades Profesionales/mortalidad , Factores de Riesgo
8.
J Occup Environ Med ; 43(9): 741-56, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11561358

RESUMEN

This 1986 to 1992 update and expansion of an earlier historical cohort study examined the 1946 to 1992 mortality experience of 32,110 workers employed for 1 year or more during 1945 to 1978 at any of 10 US fiberglass (FG) manufacturing plants. Included are (1) a new historical exposure reconstruction for respirable glass fibers and several co-exposures (arsenic, asbestos, asphalt, epoxy, formaldehyde, polycyclic aromatic hydrocarbons, phenolics, silica, styrene, and urea); and (2) a nested, matched case-control study of 631 respiratory system cancer (RSC) deaths in male workers during 1970 to 1992 with interview data on tobacco smoking history. Our findings to date from external comparisons based on standardized mortality ratios (SMRs) in the cohort study provide no evidence of excess mortality risk from all causes combined, all cancers combined, and non-malignant respiratory disease. Also, excluding RSC, we observed no evidence of excess mortality risk from any of the other cause-of-death categories considered. For RSC among the total cohort, we observed a 6% excess (P = 0.05) based on 874 deaths. Among long-term workers (5 or more years of employment) we observed a not statistically significant 3% excess based on 496 deaths. Among the total cohort, we observed increases in RSC SMRs with calendar time and time since first employment, but these were less pronounced among long-term workers. RSC SMRs were not related to duration of employment among the total cohort or long-term workers. In an externally controlled analysis of male workers at risk between 1970 and 1992, we observed no association between RSC SMRs and increasing exposure to respirable FG. Our findings to date from internal comparisons based on rate ratios in the case-control study of RSC were limited to analyses of categorized study variables with and without adjustment for smoking. On the basis of these analyses, the duration of exposure and cumulative exposure to respirable FG at the levels encountered at the study plants did not appear to be associated with an increased risk of RSC. RSC risk also did not seem to increase with time since first employment. There is some evidence of elevated RSC risk associated with non-baseline levels of average intensity of exposure to respirable glass, but when adjusted for smoking this was not statistically significant, and there was no apparent trend with increasing exposure. This same pattern of findings was observed for duration of exposure, cumulative exposure, and average intensity of exposure to formaldehyde. None of the other individual co-exposures encountered in the study plants appeared to be associated with an increased risk of RSC. The primary focus of ongoing analyses is to determine the extent to which our present findings are robust to alternative characterizations of exposure.


Asunto(s)
Vidrio , Enfermedades Pulmonares/inducido químicamente , Enfermedades Pulmonares/mortalidad , Neoplasias Pulmonares/inducido químicamente , Neoplasias Pulmonares/mortalidad , Exposición Profesional/efectos adversos , Adulto , Estudios de Casos y Controles , Causas de Muerte , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Masculino , Enfermedades Profesionales/inducido químicamente , Enfermedades Profesionales/mortalidad , Valor Predictivo de las Pruebas , Riesgo , Fumar/efectos adversos , Análisis de Supervivencia , Sobrevivientes , Factores de Tiempo , Estados Unidos/epidemiología
9.
J Occup Environ Med ; 43(9): 757-66, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11561359

RESUMEN

As part of our ongoing mortality surveillance program for the US man-made vitreous fiber (MMVF) industry, we examined mortality from malignant mesothelioma using data from our 1989 follow-up of 3478 rock/slag wool workers and our 1992 follow-up of 32,110 fiberglass workers. A manual search of death certificates for 1011 rock/slag wool workers and 9060 fiberglass workers revealed only 10 death certificates with any mention of the word "mesothelioma." A subsequent review of medical records and pathology specimens for 3 of the 10 workers deemed two deaths as definitely not due to mesothelioma and one as having a 50% chance of being caused by mesothelioma. Two other deaths, for which only medical records were available, were given less than a 50% chance of being due to mesothelioma. Eight of the 10 decedents had potential occupational asbestos exposure inside or outside the MMVF industry. We also estimated the mortality risk from malignant mesothelioma in the cohort using two cause-of-death categorizations that included both malignant and benign coding rubrics. Using the more comprehensive scheme, we observed overall deficits in deaths among the total cohort and fiberglass workers and an overall excess among rock/slag wool workers. The excess in respiratory system cancer is largely a reflection of elevated lung cancer risks that we attributed mainly to confounding by smoking, to exposures outside the MMVF industry to agents such as asbestos, or to one or more of the several co-exposures present in many of the study plants (including asbestos). The second scheme, which focused on pleural mesothelioma in time periods when specific malignant mesothelioma coding rubrics were available, classified only one cohort death as being caused by malignant mesothelioma, compared with 2.19 expected deaths (local county comparison). We conclude that the overall mortality risk from malignant mesothelioma does not seem to be elevated in the US MMVF cohort.


Asunto(s)
Vidrio , Mesotelioma/inducido químicamente , Mesotelioma/mortalidad , Exposición Profesional/efectos adversos , Neoplasias del Sistema Respiratorio/inducido químicamente , Neoplasias del Sistema Respiratorio/mortalidad , Adulto , Causas de Muerte , Estudios de Cohortes , Femenino , Estudios de Seguimiento , Humanos , Masculino , Mesotelioma/patología , Persona de Mediana Edad , Enfermedades Profesionales/inducido químicamente , Enfermedades Profesionales/mortalidad , Factores Sexuales , Encuestas y Cuestionarios , Análisis de Supervivencia , Textiles/efectos adversos , Estados Unidos/epidemiología
10.
J Occup Environ Med ; 43(9): 767-78, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11561360

RESUMEN

The most recent findings of our nested case-control study of respiratory system cancer (RSC) among male fiberglass workers showed some evidence of elevated RSC risk associated with non-baseline levels of average intensity of exposure (AIE) to respirable fibers (RFib). When adjusted for smoking, this was not statistically significant, and no trend was apparent with increasing levels of exposure. Similar findings for RSC were noted for both cumulative exposure (Cum) and AIE to formaldehyde (FOR). In this reanalysis of our nested case-control study, we explored a possible exposure-response relationship between RSC and exposure to RFib or FOR using exposure weighting as an alternative characterization of exposure. Because of the uncertainties in selecting an appropriate exposure-weighting scheme, a range of plausible time lags and unlagged/lagged time windows was considered. As in the initial analysis of the nested case-control study, RFib and FOR exposures were categorized at the deciles of the RSC case distribution. For none of the exposure weighting schemes considered did we observe an increasing RSC risk with increasing levels of RFib_Cum or RFib_AIE. The exposure-weighted estimated risk ratios (RR) for both RFib_Cum and RFib_AIE were generally lower than those obtained from an unweighted model. For FOR_Cum, RRs were generally lower for the time-lagged and unlagged time window models than for the unweighted models, although some decile-specific RRs were higher for the lagged time window models. The exposure-weighted RRs for FOR_AIE were generally lower than the unweighted RRs for all of the weighting schemes considered. This reanalysis in terms of categorized exposures reveals no exposure-response relationships that were undetected in the original analysis where unweighted exposure measures were used. In the schemes considered, exposure weighting generally reduced the estimated risk of RSC.


Asunto(s)
Vidrio , Exposición Profesional/efectos adversos , Neoplasias del Sistema Respiratorio/inducido químicamente , Adulto , Estudios de Casos y Controles , Estudios de Cohortes , Estudios de Seguimiento , Formaldehído/efectos adversos , Humanos , Masculino , Enfermedades Profesionales/inducido químicamente , Enfermedades Profesionales/mortalidad , Neoplasias del Sistema Respiratorio/mortalidad , Riesgo , Sensibilidad y Especificidad , Análisis de Supervivencia , Factores de Tiempo , Estados Unidos/epidemiología
11.
J Occup Environ Med ; 43(9): 779-92, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11561361

RESUMEN

As part of the 1992 update of an historical cohort study of 32,110 workers employed for at least 1 year in any of 10 US fiberglass manufacturing plants, a nested case-control study was done in which data on tobacco smoking were obtained for 631 male case subjects with respiratory system cancer (RSC) and 570 control subjects matched on age and year of birth. In this more extensive analysis of the nested case-control data, we provide a detailed assessment of the most prominent findings from the initial report. We expand the scope of the analysis to consider quantitative measures of exposure to respirable fibers (RFib), formaldehyde (FOR), and silica (Sil) and consider these and other exposures together in the same model. We investigate the functional form of possible exposure-response relationships between RSC risk, RFib, and FOR. In addition, we address the statistical issues of collinearity, effect modification, and potential confounding by coexposures. All analyses are adjusted for smoking. Neither measure of exposure to RFib (average intensity of exposure or cumulative exposure) was statistically significantly associated with RSC risk in any of the hundreds of fractional polynomial models considered. This more extensive analysis has substantiated our initial finding of no apparent exposure-response relationship between RSC risk and either cumulative or average intensity of exposure to RFib at the levels experienced by these workers. This study provides some evidence of increased RSC risk among workers at the higher observed levels of average intensity of exposure to FOR and/or Sil. No positive associations were identified between RSC risk and any of the other exposures considered in this case-control study.


Asunto(s)
Vidrio , Minerales/efectos adversos , Exposición Profesional/efectos adversos , Neoplasias del Sistema Respiratorio/inducido químicamente , Adulto , Estudios de Casos y Controles , Estudios de Cohortes , Estudios de Seguimiento , Formaldehído/efectos adversos , Humanos , Masculino , Enfermedades Profesionales/inducido químicamente , Enfermedades Profesionales/mortalidad , Valor Predictivo de las Pruebas , Tiempo de Reacción/fisiología , Neoplasias del Sistema Respiratorio/mortalidad , Factores de Riesgo , Fumar/efectos adversos , Sobrevivientes , Estados Unidos/epidemiología
12.
J Occup Environ Med ; 43(9): 793-802, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11561362

RESUMEN

As part of our ongoing mortality surveillance program for the US man-made vitreous fiber industry, we surveyed a random sample of study members to estimate tobacco-smoking habits for the total cohort. Separate sampling frames were constructed for four study groups: male and female workers within the fiberglass and rock/slag wool subcohorts. The frames included all persons who had worked a year or more between 1945 and 1986 (with some exceptions), and who were alive as adults (18+ years) on January 1, 1980, the year the age distribution of the cohort most resembled the US comparison population. Subjects were randomly selected from the frames, and a structured telephone interview was administered to the subject or a proxy respondent between January 1995 and December 1997. Using survey data, we estimated the point prevalence of ever and current cigarette smoking on January 1, 1980, and made comparisons with other occupational groups and general populations. Overall response rates (interviews/targeted sample) were greater than 78% for each of the four study groups. From our estimates, we infer that male workers from both the fiberglass and rock/slag wool cohorts and female rock/slag wool workers had higher rates of ever smoking than the corresponding general populations of the United States and most of the states where the study plants were located. These findings suggest that at least part of the elevated externally standardized mortality ratios (US and regional rate-based) for respiratory system cancer noted among male subjects and the male-dominated total cohort in our previous cohort analyses were due to uncontrolled positive confounding by smoking.


Asunto(s)
Vidrio , Enfermedades Profesionales/inducido químicamente , Enfermedades Profesionales/mortalidad , Exposición Profesional/efectos adversos , Adolescente , Adulto , Factores de Edad , Anciano , Estudios de Casos y Controles , Estudios de Cohortes , Recolección de Datos , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Sensibilidad y Especificidad , Factores Sexuales , Fumar/efectos adversos , Fumar/epidemiología , Análisis de Supervivencia , Estados Unidos/epidemiología
13.
J Occup Environ Med ; 43(9): 803-8, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11561363

RESUMEN

To date, the US cohort study of man-made vitreous fiber workers has provided no consistent evidence of a relationship between man-made vitreous fiber exposure and mortality from malignant or non-malignant respiratory disease. Nevertheless, there have been small, overall excesses in respiratory system cancer (RSC) among workers from the fiberglass and rock/slag wool production plants included in the study that were unexplained by estimated worker exposures to respirable fiber or other agents present in the plants. The present investigation was designed to provide a quantitative estimate of the extent to which the overall excess in RSC mortality observed at the total cohort level among male fiberglass and rock/slag wool workers is a result of the positive confounding effects of cigarette smoking. Because cigarette-smoking data were neither available nor obtainable at the individual level for all members of the fiberglass and rock/slag wool cohorts, we used the "indirect" method to adjust RSC standardized mortality ratios (SMRs) at the group (cohort and plant) level. Our adjustment suggested that cigarette smoking accounts for all of the 7% and 24% excesses in RSC observed, respectively, for the male fiberglass and rock/slag wool cohorts in the latest mortality updates. The same conclusion was reached regardless of which of several alternative formulations were used to adjust local rate-based RSC SMRs. We found that our smoking adjustments were robust with respect to several alternative characterizations and (with the exception of one fiberglass plant) produced adjusted RSC SMRs that were lower than their unadjusted counterparts. Further, all statistically significantly elevated unadjusted SMRs were reduced to not statistically significant levels. These results reaffirm that RSC SMRs based on US and local rates must take into account the potential confounding effects of cigarette smoking. They also suggest that the use of local county mortality rate-based SMRs may not help to adjust for cigarette smoking to the degree suggested by some investigators.


Asunto(s)
Vidrio , Exposición Profesional/efectos adversos , Neoplasias del Sistema Respiratorio/inducido químicamente , Adolescente , Adulto , Estudios de Casos y Controles , Estudios de Cohortes , Humanos , Masculino , Enfermedades Profesionales/inducido químicamente , Prevalencia , Riesgo , Fumar/efectos adversos , Fumar/epidemiología , Breas/efectos adversos , Estados Unidos/epidemiología
14.
J Occup Environ Med ; 43(9): 809-23, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11561364

RESUMEN

Data and procedures used to reconstruct the history of exposures at each of the 15 plants (19 distinct sites) are presented. The assessment consisted of five steps: (1) develop a Technical History of operations, stable periods, and time points of changes relevant for exposures, and identify the presence of potentially confounding co-exposures; (2) develop a set of unique department-job names with descriptions and a Job Dictionary for all verbatim names in work histories; (3) collect all company and other exposure data (> 1600 observed), and develop quantitative fiber, formaldehyde, and silica exposure estimates; (4) integrate estimates with the Technical History to make Exposure Extrapolation Tables; and (5) use the the Tables with job data to develop an Exposure Matrix for each plant. Nineteen Exposure Matrices were made, with 82 to 621 lines, covering up to 54 years of operations.


Asunto(s)
Vidrio/análisis , Exposición Profesional/análisis , Contaminantes Ocupacionales del Aire/análisis , Estudios de Cohortes , Empleo , Estudios de Seguimiento , Formaldehído/análisis , Humanos , Perfil Laboral , Textiles/análisis , Factores de Tiempo , Estados Unidos/epidemiología , Lugar de Trabajo
15.
J Occup Environ Med ; 43(9): 824-34, 2001 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11561365

RESUMEN

UNLABELLED: All jobs held by a cohort of US man-made vitreous fiber production workers were analyzed for airborne fiber exposure. This exposure-specific job analysis was part of an exposure assessment for an epidemiologic study of mortality patterns, with particular focus on respiratory cancer, among 35,145 workers employed in 10 fiberglass and five rock or slag wool plants. The exposure assessment was conducted from the start-up date of each plant (1917 to 1946) to 1990. For the job analysis, 15,465 crude department names and 47,693 crude job titles were grouped into 1668 unique department and job pairs (UDJobs), which represented a job title linked to a specific department within each plant. Every UDJob was evaluated according to a set of job elements related to airborne fiber exposure. The distribution of the cohort person-years by UDJob and the job-exposure elements was then evaluated. The results show the main departments and jobs that employed the workers for each plant. The distribution of person-years varies across the job-exposure elements. The same job title was used in different departments within and across plants. When job titles not linked to departments were evaluated, the values of the job-exposure elements varied considerably across all plants and within plant. IN CONCLUSION: (1) exposure misclassification could occur if job title alone were used for the exposure assessment; (2) the job-exposure elements analysis provides an efficient way to identify major job determinants of exposure without relying on the more detailed, resource-intensive task-based approach; and (3) the evaluation of the cohort person-years by UDJobs and job-exposure elements is an effective way to identify which plants, departments, and jobs have sufficient information for making precise risk estimates in the broader epidemiologic study.


Asunto(s)
Contaminantes Ocupacionales del Aire/análisis , Vidrio/análisis , Exposición Profesional/análisis , Estudios de Cohortes , Humanos , Sensibilidad y Especificidad , Textiles/análisis , Factores de Tiempo , Estados Unidos/epidemiología , Lugar de Trabajo
16.
Scand J Work Environ Health ; 27(1): 5-13, 2001 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-11266147

RESUMEN

OBJECTIVES: The present study provides additional analyses of data obtained earlier on lung cancer risk among workers with acrylonitrile exposure. METHODS: The original authors provided the data. For total mortality and the cancer sites of a priori interest (lung, stomach, brain, breast, prostate, and the lymphatic and hematopoietic systems), standardized mortality ratios (SMR) and 95% confidence intervals (95% CI) were computed, the total United States and surrounding counties being used as standard populations. Regional rate-based SMR values were also computed between lung cancer and cumulative acrylonitrile exposure. RESULTS: Except for lung cancer, the external comparisons corroborated the earlier internal comparisons (no increased cancer mortality risk). For lung cancer, the external comparisons revealed death deficits for the unexposed workers (SMR 0.68, 95% CI 0.5-0.9) and all categories of acrylonitrile-exposed workers. The SMR obtained using external rates and the most exposed group (SMR 0.92. 95% CI 0.6-1.4) differed from the corresponding relative risk (RR) of the internal rates (RR 1.5, 95% CI 0.9-2.4). CONCLUSIONS: The analysis of the present study provides little evidence that acrylonitrile exposure increases the mortality risk of cancers of a priori interest, including lung cancer. The lung cancer findings of the external comparison differed from the earlier findings of the internal comparisons. Selection bias (as the healthy worker effect) was probably not responsible. Additional follow-up and analyses, especially of the unexposed workers with low lung cancer rates, may help elucidate the internal and external comparison differences. Results from both comparisons should be presented when the relative risks differ markedly, as both have advantages and disadvantages.


Asunto(s)
Acrilonitrilo/efectos adversos , Carcinógenos/efectos adversos , Causas de Muerte , Industria Química , Neoplasias Pulmonares/inducido químicamente , Neoplasias Pulmonares/mortalidad , Exposición Profesional/efectos adversos , Acrilonitrilo/química , Adulto , Neoplasias de la Mama/inducido químicamente , Neoplasias de la Mama/mortalidad , Carcinógenos/química , Neoplasias del Sistema Nervioso Central/inducido químicamente , Neoplasias del Sistema Nervioso Central/mortalidad , Estudios de Cohortes , Intervalos de Confianza , Bases de Datos Factuales/normas , Femenino , Neoplasias Hematológicas/inducido químicamente , Humanos , Incidencia , Masculino , Persona de Mediana Edad , National Institute for Occupational Safety and Health, U.S. , Neoplasias de la Próstata/inducido químicamente , Neoplasias de la Próstata/mortalidad , Sistema de Registros , Factores de Riesgo , Neoplasias Gástricas/inducido químicamente , Neoplasias Gástricas/mortalidad , Análisis de Supervivencia , Estados Unidos/epidemiología
17.
Transplantation ; 70(9): 1335-42, 2000 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-11087149

RESUMEN

BACKGROUND: Liver transplantation (LTx) for alcohol-related liver disease (ALD) is an accepted modality of treatment and is one of the most common indications for LTx in the United States. The present report examines the long-term patient survival, graft survival, rates of recidivism, and development of de novo cancers in this group, and compares these results with a contemporaneous group of patients who were transplanted for non-ALD indications. METHODS: Between August 1989 and December 1992, 185 adults received LTx for ALD (group I). During the same time interval, 649 adults received LTx for non-ALD (group II). The mean follow-up time was 94+/-10.7 months for group I vs. 92+/-11 months for group II. Kaplan-Meier survival estimates and the incidence of cancers using Surveillance Epidemiologic End Result data were compared in both groups. RESULTS: At 5 years after orthotopic LTx, the overall patient survival and graft survival for group I were 72.0% and 66.5% vs. 66.5% and 60.3% for group II, respectively. After 5 years, the patient survival and graft survival for the alcoholic group were significantly lower (P=0.001) compared to the non-alcoholic group. The rate of de novo oropharyngeal cancer and lung cancer was 25.5 times and 3.7 times higher, respectively, in ALD group compared with the general population matched for age, sex, and length of follow-up (P=0.001), whereas this was not higher in the non-ALD group. Prior pretransplant length of sobriety and alcohol rehabilitation was not associated with the rate of post-LTx rate of recidivism, which was 20%. Out of 79 deaths in group I, only 1 was attributed to recidivism and 3 to noncompliance with recidivism. The other deaths occurred from de novo cancer (n=13), posttransplant lymphoproliferative disorder (n=5), age-related complications (n=23), and other infection or miscellaneous causes (n=34). CONCLUSIONS: Patient and graft survival past 5 years after orthotopic LTx is significantly lower for ALD for a variety of reasons (P=0.001). The rate of upper airway malignances was significantly higher in ALD patients than for non-ALD post-LTx patients and the general public. Graft loss/death related to recidivism or chronic rejection was extremely low. More attention is needed for early diagnosis of de novo cancer and prevention of cardiorespiratory and cerebrovascular complications.


Asunto(s)
Inmunosupresores/uso terapéutico , Hepatopatías Alcohólicas/cirugía , Trasplante de Hígado , Tacrolimus/uso terapéutico , Adulto , Anciano , Carcinoma Hepatocelular/etiología , Carcinoma Hepatocelular/cirugía , Femenino , Estudios de Seguimiento , Supervivencia de Injerto/efectos de los fármacos , Humanos , Neoplasias Hepáticas/etiología , Neoplasias Hepáticas/cirugía , Trasplante de Hígado/efectos adversos , Trasplante de Hígado/inmunología , Trasplante de Hígado/mortalidad , Masculino , Persona de Mediana Edad , Tasa de Supervivencia , Factores de Tiempo
18.
Environ Health Perspect ; 108(6): 545-52, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10856029

RESUMEN

The largest U.S. population exposed to low-level radioactivity released by an accident at a nuclear power plant is composed of residents near the Three Mile Island (TMI) Plant on 28 March 1979. This paper (a collaboration of The University of Pittsburgh and the Pennsylvania Department of Health) reports on the mortality experience of the 32,135 members in this cohort for 1979-1992. We analyzed standardized mortality ratios (SMRs) using a local comparison population and performed relative risk regression modeling to assess overall mortality and specific cancer risks by confounding factors and radiation-related exposure variables. Total mortality was significantly elevated for both men and women (SMRs = 109 and 118, respectively). All heart disease accounted for 43.3% of total deaths and demonstrated elevated SMRs for heart disease of 113 and 130 for men and women, respectively; however, when controlling for confounders and natural background radiation, these elevations in heart disease were no longer evident. Overall cancer mortality was similar in this cohort as compared to the local population (male SMR = 100; female SMR = 101). In the relative risk modeling, there was a significant effect for all lymphatic and hematopoietic tissue in males in relation to natural background exposure (p = 0.04). However, no trend was noted. We found a significant linear trend for female breast cancer risk in relation to increasing levels of TMI-related likely [gamma]-exposure (p = 0.02). Although such a relationship has been noted in other investigations, emissions from the TMI incident were significantly lower than in other documented studies. Therefore, it is unlikely that this observed increase is related to radiation exposure on the day of the accident. The mortality surveillance of this cohort does not provide consistent evidence that radioactivity released during the TMI accident has a significant impact on the mortality experience of this cohort to date. However, continued follow-up of these individuals will provide a more comprehensive description of the morbidity and mortality experience of the cohort.


Asunto(s)
Mortalidad/tendencias , Liberación de Radiactividad Peligrosa , Adolescente , Adulto , Anciano , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/etiología , Causas de Muerte , Niño , Preescolar , Estudios de Cohortes , Exposición a Riesgos Ambientales , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Pennsylvania/epidemiología , Medición de Riesgo
19.
Am J Ind Med ; 36(4): 423-36, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10470007

RESUMEN

OBJECTIVES: To examine the association between exposure to acrylonitrile (AN) and cancer mortality by performing an independent and extended historical cohort study of workers from a chemical plant in Lima, Ohio included in a recent NCI-NIOSH study. METHODS: Subjects were 992 white males who were employed for three or more months between 1960 and 1996. We identified 110 deaths and cause of death for 108. Worker exposures were estimated quantitatively for AN and qualitatively for nitrogen products. Statistical analyses included U.S. and local county-based SMRs and internal relative risk regression of internal cohort rates. RESULTS: No statistically significant excess mortality risks were observed among the total cohort for the cancer sites implicated in previous studies: stomach, lung, breast, prostate, brain, and hematopoietic system. We observed a statistically significant bladder cancer excess based on four deaths (SMR=7.01, 95% CI=1.91-17.96) among workers not exposed to AN. Among 518 AN-exposed workers, we observed a not statistically significant excess of lung cancer based on external (SMR=1.32, 95% CI=.60-2.51) and internal (RR=1.98, 95% CI=.60-6.90) comparisons. Although the trends were not statistically significant, exposure-response analyses of internal cohort rates showed monotonically increasing lung cancer rate ratios with increasing AN exposure, with RRs exceeding 2.0 in the highest exposure categories. CONCLUSIONS: With the possible exception of lung cancer, this study provides little evidence that exposure to AN at levels experienced by Lima plant workers is associated with an increased risk of death from any cause including the implicated cancer sites.


Asunto(s)
Acrilonitrilo/efectos adversos , Industria Química , Neoplasias/mortalidad , Compuestos de Nitrógeno/efectos adversos , Exposición Profesional , Adulto , Neoplasias Encefálicas/mortalidad , Neoplasias de la Mama/mortalidad , Estudios de Cohortes , Intervalos de Confianza , Femenino , Neoplasias Hematológicas/mortalidad , Humanos , Neoplasias Pulmonares/mortalidad , Masculino , Persona de Mediana Edad , National Institute for Occupational Safety and Health, U.S. , National Institutes of Health (U.S.) , Ohio/epidemiología , Neoplasias de la Próstata/mortalidad , Análisis de Regresión , Factores de Riesgo , Neoplasias Gástricas/mortalidad , Estados Unidos , Neoplasias de la Vejiga Urinaria/mortalidad
20.
Occup Environ Med ; 56(3): 181-90, 1999 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-10448327

RESUMEN

OBJECTIVE: To update the mortality experience of a cohort of 8508 workers with potential exposure to acrylamide at three plants in the United States from 1984-94. METHODS: Analyses of standardised mortality ratios (SMR) with national and local rates and relative risk (RR) regression modelling were performed to assess site specific cancer risks by demographic and work history factors, and exposure indicators for acrylamide and muriatic acid. RESULTS: For the 1925-94 study period, excess and deficit overall mortality risks were found for cancer sites of interest: brain and other central nervous system (CNS) (SMR 0.65, 95% confidence interval (95% CI) 0.36 to 1.09), thyroid gland (SMR 2.11, 95% CI 0.44 to 6.17), testis and other male genital organs (SMR 0.28, 95% CI 0.01 to 1.59), and cancer of the respiratory system (SMR 1.10, 95% CI 0.99 to 1.22); however, none was significant or associated with exposure to acrylamide. A previously reported excess mortality risk of cancer of the respiratory system at one plant remained increased among workers with potential exposure to muriatic acid (RR 1.50, 95% CI 0.86 to 2.59), but was only slightly increased among workers exposed or unexposed to acrylamide. In an exploratory exposure-response analysis of rectal, oesophageal, pancreatic, and kidney cancer, we found increased SMRs for some categories of exposure to acrylamide, but little evidence of an exposure-response relation. A significant 2.26-fold risk (95% CI 1.03 to 4.29) was found for pancreatic cancer among workers with cumulative exposure to acrylamide > 0.30 mg/m3.years; however, no consistent exposure-response relations were detected with the exposure measures considered when RR regression models were adjusted for time since first exposure to acrylamide. CONCLUSION: The contribution of 1115 additional deaths and nearly 60,000 person-years over the 11 year follow up period corroborate the original cohort study findings of little evidence for a causal relation between exposure to acrylamide and mortality from any cancer sites, including those of initial interest. This is the most definitive study of the human carcinogenic potential of exposure to acrylamide conducted to date.


Asunto(s)
Acrilamida/efectos adversos , Neoplasias/mortalidad , Enfermedades Profesionales/mortalidad , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Estudios de Cohortes , Estudios de Seguimiento , Humanos , Ácido Clorhídrico/efectos adversos , Masculino , Persona de Mediana Edad , Neoplasias/inducido químicamente , Enfermedades Profesionales/inducido químicamente , Exposición Profesional/efectos adversos , Neoplasias del Sistema Respiratorio/inducido químicamente , Neoplasias del Sistema Respiratorio/mortalidad , Estados Unidos/epidemiología
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