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1.
Aesthetic Plast Surg ; 46(3): 1025-1041, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35138423

RESUMEN

BACKGROUND: Gynecomastia is nowadays a very common disease, affecting a large cohort of patients with different ages. The aim of this literature review is to assess the incidence of complications with all proposed techniques and for combined procedures versus single approach procedures in gynecomastia correction. MATERIALS AND METHODS: A systematic review of the literature was performed to identify all reported techniques for gynecomastia correction covering a period from January 1, 1987 to November 1, 2020. For all selected papers, demographic data, proposed technique, and complications' incidence have been recorded. RESULTS: A total number of 3970 results was obtained from database analysis. A final total number of 94 articles was obtained for 7294 patients analyzed. Patients have been divided into three groups: aspiration techniques, consisting in 874 patients (11,98%), surgical excision techniques, consisting in 2764 patients (37,90%), and combined techniques, consisting in 3656 patients (50,12%). Complications have been recorded for all groups, for a total number of 1407, of which 130 among "Aspiration techniques" group (14,87%), 847 among "Surgical excision techniques" group (30,64%), and 430 in "Combined techniques" group (11,76%). CONCLUSIONS: Several techniques have been proposed in the literature to address gynecomastia, with the potential to greatly improve self-confidence and overall appearance of affected patients. The combined use of surgical excision and aspiration techniques seems to reduce the rate of complications compared to surgical excision alone, but the lack of unique classification and the presence of several surgical techniques still represents a bias in the literature review. LEVEL OF EVIDENCE III: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Asunto(s)
Ginecomastia , Estudios de Cohortes , Bases de Datos Factuales , Estética , Ginecomastia/cirugía , Humanos , Incidencia , Masculino , Estudios Retrospectivos , Resultado del Tratamiento
2.
Aesthetic Plast Surg ; 44(5): 1577-1583, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32458041

RESUMEN

BACKGROUND: The aging process affects skin, muscle and fat of the eyes in a different manner. Their individual rejuvenation would require specific surgical treatment according to their particular demands during lower eyelid blepharoplasty. This would require the separate management of the skin and the muscle by separating them into two different flaps. Basing on the anatomy, during sub-ciliary myocutaneous incision in conventional lower eyelid transcutaneous blepharoplasty most of innervations of the lower orbicularis oculi muscle are transected and denervation sequelae at the pretarsal orbicularis oculi muscle would be expected. However, sub/ciliary approach is still popular. The absence of signs or symptom of denervation of in our large case series even though injury to the motor innervation of the orbicularis oculi muscle during the operation led the authors to investigate the discrepancy between the anatomical concept and clinical outcomes. The study aimed to investigate the residual functionality of the orbicularis oculi muscle after lower eyelid transcutaneous blepharoplasty according to Reidy Adamson-s flap. MATERIALS AND METHODS: Ten patients were enrolled in the study. Orbicularis oculi muscle functionality was investigated with electroneurography before and at least 6 months after the surgical procedure. Investigated parameters are: Compound Muscle Action Potential (CMAP) as expressions of quantity of activated muscular fibers by the electrical stimulation of the facial nerve. Pre- and post-op collected data were compared and statistically analyzed. RESULTS: The mean age was 52.9; minimum follow-up 6 months; twenty eyes were investigated; 1 patient was excluded. Postoperative data did not show any significant reduction in the CMAP at all. CONCLUSION: The study suggests that the buccal branch and medial branch of the zygomatic nerve of the facial nerve supplies efficiently to the orbicularis oculi innervation. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Asunto(s)
Blefaroplastia , Preescolar , Párpados/cirugía , Músculos Faciales/cirugía , Humanos , Músculos Oculomotores/cirugía , Trasplante de Piel
3.
J Reconstr Microsurg ; 35(3): 189-193, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30112753

RESUMEN

BACKGROUND: The creation of skin flaps based on small perforator vessels is an increasingly popular procedure nowadays; the optimization of their blood supply enhances surgical success. This study evaluates the effects on the flowmetries of 7 days' negative pressure application on the skin surface overlying the muscle fascia emergence of periumbilical perforators of the deep inferior epigastric artery (DIEA). METHODS: Ten volunteer participants were enrolled. In each subject, one periumbilical perforator of the DIEA was identified on each side of the abdomen using an eco-color-Doppler. One of them was used as the control group, while the other (the study group) underwent 80 mm Hg negative pressure for 7 days. The flowmetries of both perforators were measured before and after the application of negative pressure wound therapy. RESULTS: After the application of negative pressure, randomly applied on the skin surface over one of the two selected periumbilical perforators, an increase in the flowmetries was observed in both groups of perforators (2.74 cm/s; p < 0.0001). The relative flowmetry increase in the control group was 9.55% (2.735 cm/s), while in the study group it was 44.03% (8.748 cm/s). CONCLUSION: The application of negative pressure system on the skin surface over the muscle fascia emergence of the selected periumbilical perforators showed an increase in flowmetry. Although this is a preliminary study, this simple and economical procedure before surgery could be usefully employed to increase the rate of success in microsurgical procedures.


Asunto(s)
Arterias/diagnóstico por imagen , Terapia de Presión Negativa para Heridas , Colgajo Perforante/irrigación sanguínea , Adulto , Arterias/fisiología , Femenino , Voluntarios Sanos , Humanos , Masculino , Ultrasonografía Doppler en Color , Adulto Joven
4.
Popul Space Place ; 25(4): e2237, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-31244559

RESUMEN

This paper documents the expansion of new family patterns in Italy by scrutinising the spatial diffusion of one-parent families across Italian municipalities for the period 1991-2011. We apply a hierarchical Bayesian model to the data of the last three Italian Population Censuses, acknowledging that variation cannot be broken down into temporal and spatial effects because space-time interaction is at the very heart of family changes. Our results illustrate substantial subregional and sub-provincial heterogeneities in the spatial organisation of family systems, patterns that might have gone undetected had larger territorial units of analysis been considered. In addition, we show that especially socio-economic factors were associated to the diffusion of new family forms. This paper challenges international scholarship that caricatures Italy as a monolithic, homogeneous family-oriented country.

5.
Aesthetic Plast Surg ; 41(4): 878-886, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28374301

RESUMEN

BACKGROUND: Pectus excavatum (PE) is one of the most frequent thoracic malformations. Generally, the malformation is not associated with functional disorders and often constitutes an aesthetic alteration with significant psychological distress. OBJECTIVES: To reduce the visibility of the residual scarring produced by corrective surgery and to improve the aesthetic outcome, the authors propose a new prosthetic implant technique through a periareolar access. METHODS: From January 2005 to January 2015, 11 patients affected with PE underwent the surgical procedure with a sternal prosthesis implanted through a periareolar access with the help of a fiberscope. The preoperative evaluation of the perception of the malformation and postoperation results were made using different questionnaires. The data collected in our series were compared with that reported in 4 different papers where other forms of access were used: sternal, inframammary and transumbilical. RESULTS: No major complications or dislocation of the implants were reported. Among the complications, 6 postoperative seromas were reported. The patients' perception of improvement through the use of 2 questionnaires and an evaluation scale showed substantial improvement in all the aesthetic outcomes. CONCLUSIONS: The periareolar technique provides excellent cosmetic results compared to the sternal one. This access causes fewer complications and necessitates a shorter average hospital stay than the sternum access. To conclude, according to what is shown in the literature, periareolar access seems to be a quicker procedure, requiring a shorter stay in hospital, and results in scars that can more easily be hidden and are more accepted by patients. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .


Asunto(s)
Tórax en Embudo/cirugía , Procedimientos de Cirugía Plástica/métodos , Prótesis e Implantes , Implantación de Prótesis/métodos , Geles de Silicona , Adulto , Estudios de Cohortes , Estética , Femenino , Estudios de Seguimiento , Tórax en Embudo/diagnóstico , Humanos , Masculino , Pezones , Pronóstico , Diseño de Prótesis , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Resultado del Tratamiento , Adulto Joven
6.
Stat Med ; 33(27): 4805-24, 2014 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-25042758

RESUMEN

We introduce a semi-parametric approach to ecological regression for disease mapping, based on modelling the regression M-quantiles of a negative binomial variable. The proposed method is robust to outliers in the model covariates, including those due to measurement error, and can account for both spatial heterogeneity and spatial clustering. A simulation experiment based on the well-known Scottish lip cancer data set is used to compare the M-quantile modelling approach with a disease mapping approach based on a random effects model. This suggests that the M-quantile approach leads to predicted relative risks with smaller root mean square error. The paper concludes with an illustrative application of the M-quantile approach, mapping low birth weight incidence data for English Local Authority Districts for the years 2005-2010.


Asunto(s)
Distribución Binomial , Mapeo Geográfico , Análisis de Regresión , Análisis Espacial , Simulación por Computador , Inglaterra , Métodos Epidemiológicos , Humanos , Recién Nacido de Bajo Peso , Recién Nacido , Neoplasias de los Labios/epidemiología , Método de Montecarlo , Factores de Riesgo , Escocia/epidemiología
7.
Biom J ; 56(1): 141-56, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24214421

RESUMEN

Linear-mixed models are frequently used to obtain model-based estimators in small area estimation (SAE) problems. Such models, however, are not suitable when the target variable exhibits a point mass at zero, a highly skewed distribution of the nonzero values and a strong spatial structure. In this paper, a SAE approach for dealing with such variables is suggested. We propose a two-part random effects SAE model that includes a correlation structure on the area random effects that appears in the two parts and incorporates a bivariate smooth function of the geographical coordinates of units. To account for the skewness of the distribution of the positive values of the response variable, a Gamma model is adopted. To fit the model, to get small area estimates and to evaluate their precision, a hierarchical Bayesian approach is used. The study is motivated by a real SAE problem. We focus on estimation of the per-farm average grape wine production in Tuscany, at subregional level, using the Farm Structure Survey data. Results from this real data application and those obtained by a model-based simulation experiment show a satisfactory performance of the suggested SAE approach.


Asunto(s)
Modelos Estadísticos , Análisis Espacial , Vitis/química , Vino/estadística & datos numéricos , Teorema de Bayes , Italia
8.
J Glob Antimicrob Resist ; 28: 274-281, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35092828

RESUMEN

OBJECTIVES: The aim of this study was to evaluate the impact of resistance mutations on efficacy of dolutegravir-based two-drug regimens (2DR). METHODS: Virologically suppressed patients with HIV-1 switching to dolutegravir + lamivudine or rilpivirine or to a dolutegravir-based three-drug regimen (3DR) with pre-baseline genotype were selected. Virological failure (VF) was defined as one HIV-RNA viral load (VL) >200 cps/mL or two consecutive VL >50 cps/mL; treatment failure (TF) was defined as VF or treatment discontinuation (TD). Resistance was defined as at least low-level resistance to at least one drug of the current regimen. Propensity score matching was used to conduct adjusted analyses within a competing risks framework. RESULTS: A total of 971 dolutegravir-based regimens were selected: 339 (34.9%) 2DR and 632 (65.1%) 3DR. The adjusted cumulative 48-week incidence of VF was 4.2% (90% CI 3.1%-5.3%) with 2DR and 4.7% (90% CI 3.5%-5.8%) with 3DR. The cumulative 48-week incidence of TF was 15.8% (90% CI 13.9%-17.9%) with 2DR and 24.5% (90% CI 22.2%-27.0%) with 3DR. For VF, the estimated hazard ratio (HR) for 2DR vs. 3DR was 1.02 (90% CI: 0.78-1.34), with evidence of effect modification by low-level resistance (HR 3.96, 90% CI: 2.10-7.46). The estimated HR of TF for 2DR vs. 3DR was 0.54 (90% CI: 0.48-0.60). The 48-week cumulative incidence of TD was 11.7% (8.7%, 14.6%) in 2DR and 19.6% (16.9%, 22.4%) in 3DR. CONCLUSIONS: Dolutegravir-based 2DR showed high virological efficacy and durability; however, past resistance increased the risk of VF, but not of TD or TF.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Fármacos Anti-VIH/farmacología , Fármacos Anti-VIH/uso terapéutico , Estudios de Cohortes , Infecciones por VIH/tratamiento farmacológico , Compuestos Heterocíclicos con 3 Anillos , Humanos , Lamivudine/uso terapéutico , Mutación , Oxazinas , Piperazinas , Piridonas , Rilpivirina/uso terapéutico
9.
Cancer Manag Res ; 12: 4615-4624, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32606954

RESUMEN

PURPOSE: Lung cancer is considered as a common cause of cancer mortality. The disease represents the second and third causes of deaths from cancer among Iranian women and men, respectively. The present study aimed to evaluate the spatial variations in relative risk of lung cancer mortality in Iran and its relation to common risk factors between men and women and specific risk factors among women. METHODS: In this ecological study, the lung cancer mortality data were analyzed in Iran during 2011-2014. Besag, York, and Mollie's (BYM) model and shared component model (SCM) were used to compare the spatial variations of the relative risk of lung cancer mortality by applying OpenBUGS version 3.2.3 and R version 3.6.1. RESULTS: The median age for death due to lung cancer in Iran is 74 years. During 2011-2014, the age-standardized lung cancer mortality rates among men and women were 12 and 5 per 100,000 individuals, respectively. In addition, almost similar spatial patterns were observed for both men and women. Further, risk factors, which are shared between men and women, were considered as the main cause of variation of lung cancer mortality relative risk in the regions under study for both men and women. The highest impact of the women-specific risk factors was estimated in northeastern and southwestern of the country while the lowest was related to Gilan province in northern part of Iran. CONCLUSION: Based on the spatial pattern, lung cancer risk factors are at relatively high levels in most parts of Iran, especially in the northwest of the country. Regarding the women, the high-risk regions were considerably extended. Further, the highest concentration of the specific risk factors among women was observed in the eastern, central, and southwestern parts. The smoking effect, and the second-smoking effect and environmental pollutions could play more significant roles for men and women, respectively.

10.
Comput Math Methods Med ; 2018: 4964569, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29796059

RESUMEN

Lung cancer mortality in Tuscany (Italy) for males, from 1971 and 2010, is investigated. A hierarchical Bayesian model for space-time disease mapping is introduced. Such a model belongs to the class of shared random effect models and exploits the birth-cohort as the relevant time dimension. It allows for highlighting common and specific patterns of risk for each birth-cohort. The results show that different birth-cohorts exhibit quite different spatial patterns, even if the socioeconomic status is taken into account. In fact, there were different occupational exposures before and after the Second World War. The birth-cohort 1930-35 exhibits high relative risks related to particular areas. This fact could be connected with occupational exposure to risk factors for silicosis, perhaps a prognostic status for lung cancer.


Asunto(s)
Neoplasias Pulmonares/mortalidad , Silicosis/complicaciones , Adulto , Anciano , Anciano de 80 o más Años , Teorema de Bayes , Estudios de Cohortes , Humanos , Italia/epidemiología , Neoplasias Pulmonares/complicaciones , Masculino , Persona de Mediana Edad , Exposición Profesional
11.
Int J Prev Med ; 9: 104, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30622687

RESUMEN

BACKGROUND: According to the last report of Iran cancer registry, stomach, colorectal, and bladder cancers are the most prevalent cancers. The present study focused on separating the latent risk surface into shared and disease-specific components. METHODS: In this study, data consisting of stomach, colorectal, and bladder cancers in 30 provinces of Iran during 2004-2009 are considered. These data are analyzed by polytomous logit model. The incidence of stomach cancer acts as the reference category (the surrogate for smoking). Then, the log odds are decomposed into shared and specific structured spatial and unstructured spatial components. These latent components help to detect spatial patterns of shared and disease-specific risk factors. RESULTS: Central, Southern, Eastern, and Southwestern provinces are supposed as high-risk regions for shared risk factor for colorectal and bladder cancers. This shared risk factor is slightly associated more with bladder than with colorectal cancer. Northern, northwestern, and central regions and also three borderline provinces in southwestern are high-risk regions for colorectal cancer. Central, eastern, southern, and western strip of the country except Ilam are found as the high-risk regions of bladder cancer. CONCLUSIONS: After considering known shared risk factor of the three cancers, it turns out that colorectal and bladder cancers have unknown shared risk factor. The significant difference in their lifestyle and eating habits could be an assumption of the risk factor.

12.
J Plast Reconstr Aesthet Surg ; 70(3): 385-391, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27986527

RESUMEN

BACKGROUND: The aging process affects the skin, muscle, and fat of the eyes in a different manner. Their individual rejuvenation would require specific surgical treatments according to their particular demands. In the present study, we analyzed the effect of an orbicularis oculi muscle flap fixed to the superior orbital rim to prevent lower eyelid dislocation during transcutaneous blepharoplasty. METHODS: The study was conducted retrospectively comparing pre- and postoperative images of two different groups of patients: group A (20 patients) treated with an orbicularis oculi flap and group B (17 patients) treated without the flap. Pre- and postoperative distances between the center of the pupil and upper border of the lower lid at the midpupillary line were measured in each photo and then compared and statistically analyzed. RESULTS: The mean age of the 37 patients was 57 years. From the estimated linear mixed model, we observed a significant effect of the presence of the flap (p-value < 0.0001). All the patients treated with the orbicularis oculi flap (group A) showed a cranial movement of the lower eyelid, although only minimally. All the patients treated without the muscle flap (Group B) showed a caudal movement of the lower eyelid. In total, 47% of the eyes in group B showed a positive variation of >10%. CONCLUSION: The study suggests that the anchorage of the orbicularis muscle flap to the upper orbital rim reinforces the lower eyelid's anterior lamellae. It efficiently stabilizes lower eyelid position after transcutaneous blepharoplasty, thus confirming clinical results and improving surgical outcomes even in patients with minimal or no eyelid laxity.


Asunto(s)
Blefaroplastia/métodos , Párpados/fisiología , Músculos Oculomotores/cirugía , Colgajos Quirúrgicos , Adulto , Anciano , Enfermedades de los Párpados/prevención & control , Humanos , Masculino , Persona de Mediana Edad , Órbita/cirugía , Periostio/cirugía , Fotograbar , Complicaciones Posoperatorias/prevención & control , Estudios Retrospectivos
13.
In Vivo ; 31(1): 111-115, 2017 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-28064228

RESUMEN

AIM: Evaluation of long-term results after aponeurotic blepharoptosis correction with external levator muscle complex advancement. PATIENTS AND METHODS: We carried out a retrospective study with medical record review of 20 patients (40 eyes) affected by bilateral aponeurotic moderate and severe ptosis who underwent primary surgery between January 2010 and December 2013. Criteria for outcome evaluations included 3-year postoperative follow-up of upper margin reflex index (uMRD) and symmetry. RESULTS: 3-Year postoperative follow-up showed 17 (85%) cases of successful correction of ptosis and three cases (15%) showed partial success. Two eyes showed hypocorrection, while one eye was overcorrected. The symmetry was maintained in all patients except for the oldest. CONCLUSION: External superior levator advancement is an effective procedure for moderate and severe aponeurotic blepharoptosis correction, and establishes good long-term eyelid position and symmetry.


Asunto(s)
Blefaroplastia/métodos , Blefaroptosis/cirugía , Interpretación Estadística de Datos , Párpados/cirugía , Músculos Oculomotores/cirugía , Complicaciones Posoperatorias , Índice de Severidad de la Enfermedad , Adulto , Anciano , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento
14.
Stat Methods Med Res ; 15(4): 337-52, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16886735

RESUMEN

Model-based geostatistics and Bayesian approaches are useful in the context of veterinary epidemiology when point data have been collected by appropriate study design. We take advantage of an example of Epidemiological Surveillance on urban settings where a two-stage sampling design with first stage transects is applied to study the risk of dog parasite infection in the city of Naples, 2004-2005. We specified Bayesian Gaussian spatial exponential models and Bayesian kriging were performed to predict the continuous risk surface of parasite infection on the study region. We compared the results with those obtained by the application of hierarchical Bayesian models on areal data (proportion of positive specimens by transect). The models results were consistent with each other and the Bayesian geostatistical approach proved to be more accurate in identifying areas at risk of zoonotic parasitic diseases. In general, larger risk areas were identified at the city border where wild dogs mixed with domestic dogs and human or urban barriers were less present.


Asunto(s)
Enfermedades de los Animales/epidemiología , Teorema de Bayes , Modelos Estadísticos , Análisis de Área Pequeña , Animales , Recolección de Datos/métodos , Enfermedades de los Perros/epidemiología , Perros , Heces/parasitología , Italia/epidemiología , Enfermedades Parasitarias en Animales/epidemiología , Vigilancia de la Población/métodos , Proyectos de Investigación , Riesgo
15.
Stat Methods Med Res ; 24(3): 373-95, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24492792

RESUMEN

A new semiparametric approach to model-based small area prediction for counts is proposed and used for estimating the average number of visits to physicians for Health Districts in Central Italy. The proposed small area predictor can be viewed as an outlier robust alternative to the more commonly used empirical plug-in predictor that is based on a Poisson generalized linear mixed model with Gaussian random effects. Results from the real data application and from a simulation experiment confirm that the proposed small area predictor has good robustness properties and in some cases can be more efficient than alternative small area approaches.


Asunto(s)
Encuestas de Atención de la Salud/métodos , Encuestas Epidemiológicas/métodos , Modelos Estadísticos , Tamaño de la Muestra , Anciano , Atención a la Salud/estadística & datos numéricos , Encuestas de Atención de la Salud/estadística & datos numéricos , Estado de Salud , Encuestas Epidemiológicas/estadística & datos numéricos , Humanos , Italia/epidemiología , Funciones de Verosimilitud , Distribución de Poisson , Análisis de Regresión , Muestreo , Encuestas y Cuestionarios
16.
Stat Methods Med Res ; 23(6): 591-610, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24847899

RESUMEN

Lung cancer incidence over 2005-2010 for 326 Local Authority Districts in England is investigated by ecological regression. Motivated from mis-specification of a Negative Binomial additive model, a semiparametric Negative Binomial M-quantile regression model is introduced. The additive part relates to those univariate or bivariate smoothing components, which are included in the model to capture nonlinearities in the predictor or to account for spatial dependence. All such components are estimated using penalized splines. The results show the capability of the semiparametric Negative Binomial M-quantile regression model to handle data with a strong spatial structure.


Asunto(s)
Neoplasias Pulmonares/epidemiología , Análisis de Regresión , Inglaterra/epidemiología , Humanos , Incidencia
17.
Geospat Health ; 2(2): 263-71, 2008 May.
Artículo en Inglés | MEDLINE | ID: mdl-18686274

RESUMEN

The relation between disease risk and a point source of pollution is usually investigated using distance from the source as a proxy of exposure. The analysis may be based on case-control data or on aggregated data. The definition of the function relating risk of disease and distance is critical, both in a classical and in a Bayesian framework, because the likelihood is usually very flat, even with large amounts of data. In this paper we investigate how the specification of the function relating risk of disease with distance from the source and of the prior distributions on the parameters of the function affects the results when case-control data and Bayesian methods are used. We consider different popular parametric models for the risk distance function in a Bayesian approach, comparing estimates with those derived by maximum likelihood. As an example we have analyzed the relationship between a putative source of environmental pollution (an asbestos cement plant) and the occurrence of pleural malignant mesothelioma in the area of Casale Monferrato (Italy) in 1987-1993. Risk of pleural malignant mesothelioma turns out to be strongly related to distance from the asbestos cement plant. However, as the models appeared to be sensitive to modeling choices, we suggest that any analysis of disease risk around a putative source should be integrated with a careful sensitivity analysis and possibly with prior knowledge. The choice of prior distribution is extremely important and should be based on epidemiological considerations.


Asunto(s)
Análisis por Conglomerados , Contaminación Ambiental/efectos adversos , Geografía , Sensibilidad y Especificidad , Amianto , Teorema de Bayes , Epidemiología , Femenino , Humanos , Industrias , Italia/epidemiología , Masculino
18.
Biom J ; 49(4): 520-9, 2007 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-17634979

RESUMEN

A statistical model for jointly analysing the spatial variation of incidences of three (or more) diseases, with common and uncommon risk factors, is introduced. Deaths for different diseases are described by a logit model for multinomial responses (multinomial logit or polytomous logit model). For each area and confounding strata population (i.e. age-class, sex, race) the probabilities of death for each cause (the response probabilities) are estimated. A specic disease, the one having a common risk factor only, acts as the baseline category. The log odds are decomposed additively into shared (common to diseases different by the reference disease) and specic structured spatial variability terms, unstructured unshared spatial terms and confounders terms (such as age, race and sex) to adjust the crude observed data for their effects. Disease specic spatially structured effects are estimated; these are considered as latent variables denoting disease-specic risk factors. The model is presented with reference to a specic application. We considered the mortality data (from 1990 to 1994) relative to oral cavity, larynx and lung cancers in 13 age groups of males, in the 287 municipalities of Region of Tuscany (Italy). All these pathologies share smoking as a common risk factor; furthermore, two of them (oral cavity and larynx cancer) share alcohol consumption as a risk factor. All studies suggest that smoking and alcohol consumption are the major known risk factors for oral cavity and larynx cancers; nevertheless, in this paper, we investigate the possibility of other different risk factors for these diseases, or even the presence of an interaction effect (between smoking and alcohol risk factors) but with different spatial patterns for oral and larynx cancer. For each municipality and age-class the probabilities of death for each cause (the response probabilities) are estimated. Lung cancer acts as the baseline category. The log odds are decomposed additively into shared (common to oral cavity and larynx diseases) and specic structured spatial variability terms, unstructured unshared spatial terms and an age-group term. It turns out that oral cavity and larynx cancer have different spatial patterns for residual risk factors which are not the typical ones such as smoking habits and alcohol consumption. But, possibly, these patterns are due to different spatial interactions between smoking habits and alcohol consumption for the first and the second disease.


Asunto(s)
Biometría/métodos , Comorbilidad , Interpretación Estadística de Datos , Ambiente , Neoplasias Pulmonares/epidemiología , Neoplasias de la Boca/epidemiología , Medición de Riesgo/métodos , Humanos , Italia/epidemiología , Masculino , Factores de Riesgo
19.
Geospat Health ; 2(1): 97-104, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18686259

RESUMEN

A cross-sectional survey was carried out on 2004-2005 in the Campania region, southern Italy, to study the multivariate geographical distribution of four different sheep helminths, i.e. Fasciola hepatica (liver fluke), Calicophoron (Paramphistomum) daubneyi (rumen fluke), Dicrocoelium dendriticum (lancet fluke), and the gastrointestinal strongyle Haemonchus contortus. A series of multivariate Bayesian hierarchical models based on square root transformation of faecal egg counts were performed. The results were consistent with theoretical knowledge of the biology and epidemiology of the four studied helminths. In particular, the impact of common intermediate hosts (F. hepatica and C. daubneyi share the same intermediate host species) was quantified and evidence of previously unknown ecological components was given. D. dendriticum was correlated to F. hepatica and H. contortus was found not to be spatially associated with the previously mentioned helminths.


Asunto(s)
Heces/parasitología , Geografía , Helmintiasis Animal/epidemiología , Helmintos/aislamiento & purificación , Enfermedades de las Ovejas/parasitología , Animales , Teorema de Bayes , Estudios Transversales , Métodos Epidemiológicos , Heces/microbiología , Italia/epidemiología , Ovinos , Enfermedades de las Ovejas/epidemiología
20.
Stat Med ; 24(12): 1919-32, 2005 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-15724269

RESUMEN

The relationship between socioeconomic factors and mortality for lung cancer is investigated. To identify the proper lag time between socioeconomic factors and lung cancer mortality, a space-time hierarchical Bayesian model with time-dependent covariates is adopted. A real example on lung cancer mortality, males, in Tuscany (Italy) during the period 1971-1999, is provided. Results confirm the presence of an association between mortality for lung cancer and socioeconomic factors with a temporal lag (latency time) of at least 10 years.


Asunto(s)
Neoplasias Pulmonares/mortalidad , Modelos Estadísticos , Factores Socioeconómicos , Agrupamiento Espacio-Temporal , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Humanos , Lactante , Recién Nacido , Italia/epidemiología , Masculino , Persona de Mediana Edad , Mortalidad/tendencias
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