Radon exposure: a major cause of lung cancer.

Introduction: Lung cancer is the most important cause of cancer mortality. It is a multifactorial disease with multiple risk factors, including residential radon exposure. Areas covered: The aim of this paper was to review the epidemiology of residential radon exposure and its impact on lung cancer risk. While tobacco is the main risk factor of lung cancer, residential radon is the first cause in never-smokers and the second in ever-smokers. Moreover, the synergistic effect between tobacco consumption and radon exposure should be considered. However, the biological mechanism by which radon and its decay products induce lung cancer is not entirely known. Expert opinion: Residential radon is usually neglected by clinicians. In fact, no lung cancer risk score (predicting incidence or mortality) includes radon as a variable. Further studies are needed to find out the molecular pathways of radon that cause lung cancer and whether this radioactive gas is also involved in the development of other diseases other than lung cancer. There is a clear need to increase awareness among administrations, health professionals and the general population in order to take the necessary measures to reduce this harmful exposure, particularly in radon-prone areas.

Mortality due to KPC carbapenemase-producing Klebsiella pneumoniae infections: Systematic review and meta-analysis: Mortality due to KPC Klebsiella pneumoniae infections.

INTRODUCTION: KPC carbapenemase-producing Klebsiella pneumoniae (KPC-KP) has become a major public health challenge. Accordingly, this study sought to use a systematic review of the scientific literature to ascertain the mortality of KPC-KP infection, and analyze such mortality by country, year of publication, hospital ward, and type of interpretation used to define carbapenem resistance. METHODOLOGY: A search without language restrictions was made of the MEDLINE, CENTRAL, EBSCO, LILACS and EMBASE databases from 1996 through June 2017, to locate all studies which had determined the existence of KPC-KP infection. We then performed a meta-analysis of all studies that reported KPC-KP infection-related mortality, and analyzed mortality by subgroup in accordance with standard methodology. RESULTS: A total of 51 papers were included in the systematic review. From 2005 through 2017, data on KPC-KP infection were reported in 5124 patients, with an average of 465 patients per year. The most widely studied type of infection was bacteremia (28∙0%). The meta-analysis showed that overall mortality for the 37 studies was 41.0% (95%CI 37.0-44.0), with the highest mortality rates being observed in oncology patients, 56.0% (95%CI 38.1-73.0), and Brazil, 51.3% (95%CI 43.0-60.0). CONCLUSION: KPC-KP infection-related mortality is high, is manifested differently in some countries, and is highest among oncology patients.

Residential radon and lung cancer: a cohort study in Galicia, Spain.

Case-control studies show an association between residential radon and lung cancer. The aim of this paper is to investigate this association through a cohort study. We designed an ambispective cohort study using the Galician radon map, Spain, with controls drawn from a previous case-control study. Subjects were recruited between 2002 and 2009. The data were cross-checked to ascertain lung cancer incidence and then analysed using a Cox regression model. A total of 2,127 subjects participated; 24 lung cancer cases were identified; 76.6% of subjects were drawn from the radon map. The adjusted hazard ratio was 1.2 (95%CI: 0.5-2.8) for the category of subjects exposed to 50Bq/m3 or more. This risk rose when subjects from the case-control study were analyzed separately. In conclusion, we did not observe any statistically significant association between residential radon exposure and lung cancer; however, it appears that with a sample of greater median age (such as participants from the case-control study), the risk of lung cancer would have been higher.

Residential radon and COPD. An ecological study in Galicia, Spain.

PURPOSE: Radon is a human lung carcinogen but it might be linked with other respiratory diseases. We aimed to assess the relationship between residential radon exposure and COPD (chronic obstructive pulmonary disease) prevalence and hospital admissions at a municipal level. MATERIALS AND METHODS: We designed an ecological study where we included those municipalities with at least three radon measurements. Using mixed Poisson regression models, we calculated the relative risk (RR) for COPD for each 100 Bq/m3 of increase in radon concentration and also the relative risk for COPD using a cut-off point of 50 Bq/m3. We did not have individual data on cigarette smoking and therefore we used a proxy (bladder cancer standardized mortality rate) that has proved to account for tobacco consumption. We performed separate analyses for sex and also sensitivity analysis considering age and rurality. RESULTS: A total of 3040 radon measurements and 49,393 COPD cases were included. The relative risk for COPD prevalence was 0.95 (95% CI: 0.92-0.97) while for hospital admissions the RR was 1.04 (95% CI: 1.00-1.10) for each 100 Bq/m3. Relative risks were higher for women compared to men. Using a categorical analysis with a cut-off point of 50 Bq/m3, the RR for COPD prevalence was 1.06 (95% CI: 1.02-1.10) and for hospital admissions it was 1.08 (95% CI: 1.00-1.17) for women living in municipalities with more than 50 Bq/m3. All risks were also higher for women. No relevant differences were observed for age, rurality or other categories for radon exposure. CONCLUSION: While the influence of radon on COPD prevalence is unclear depending on the approach used, it seems that residential radon might increase the risk of hospital admissions in COPD patients. Women have a higher risk than men in all situations. Since this is an ecological study, results should be interpreted cautiously.

[Residential radon and lung cancer. An ecologic study in Galicia, Spain]. / Radón residencial y cáncer de pulmón. Un estudio ecológico en Galicia.

BACKGROUND AND OBJECTIVE: Residential radon is the second cause of lung cancer and the first in never smokers. Galicia is a high radon emission area. The objective of this study is to analyze the relationship between municipal lung cancer mortality and residential radon in Galician municipalities. MATERIAL AND METHOD: We performed an ecologic study including 192 municipalities with at least 3 residential radon measurements. The observed number of lung cancer deaths was obtained from the Galician Mortality Registry. Afterwards, we calculated the standardized mortality ratios (SMRs) of lung cancer for males and females for the period comprising 1980-2009. Median municipal residential radon concentrations were correlated with lung cancer SMRs. RESULTS: Median residential radon concentration for the included municipalities was 75 Bq/m(3), with an interquartile range of 40.7 to 154 Bq/m(3). The correlation between lung cancer SMRs and municipal radon concentration was statistically significant for males (P=.023) whereas it did not reach statistical significance for females (P=.087). CONCLUSION: There exists an association between municipal residential radon and lung cancer mortality in Galicia for males, though for women the association is not statistically significant. These results suggest that residential radon could raise the risk of lung cancer in males, though for females no association is evident.

Residential radon and lung cancer: a cohort study in Galicia, Spain / Radón residencial y cáncer de pulmón: un estudio de cohorte en Galicia, España / Radônio residencial e câncer de pulmão: um estudo de coorte na Galícia, Espanha

Case-control studies show an association between residential radon and lung cancer. The aim of this paper is to investigate this association through a cohort study. We designed an ambispective cohort study using the Galician radon map, Spain, with controls drawn from a previous case-control study. Subjects were recruited between 2002 and 2009. The data were cross-checked to ascertain lung cancer incidence and then analysed using a Cox regression model. A total of 2,127 subjects participated; 24 lung cancer cases were identified; 76.6% of subjects were drawn from the radon map. The adjusted hazard ratio was 1.2 (95%CI: 0.5-2.8) for the category of subjects exposed to 50Bq/m3 or more. This risk rose when subjects from the case-control study were analyzed separately. In conclusion, we did not observe any statistically significant association between residential radon exposure and lung cancer; however, it appears that with a sample of greater median age (such as participants from the case-control study), the risk of lung cancer would have been higher.

Los estudios de casos y controles muestran una asociación entre el radón residencial y el cáncer de pulmón. El objetivo del artículo fue investigar esa asociación a través de un estudio de cohorte. Proyectamos un estudio de cohorte ambispectivo, utilizando el mapa de radón de Galicia, España, con los controles obtenidos de un estudio anterior de casos y controles. Los individuos fueron reclutados entre 2002 y 2009. Los datos fueron verificados para confirmar la incidencia de cáncer de pulmón y después analizados con un modelo de regresión de Cox. Participaron un total de 2.127 individuos; se identificaron 24 casos de cáncer de pulmón; un 76,6% de los individuos fueron obtenidos a través del mapa de radón. El hazard ratio ajustado era 1,2 (IC95%: 0,5-2,8) para la categoría de individuos expuestos a 50Bq/m3 o más. El riesgo aumentó cuando los individuos del estudio de casos y controles fueron analizados separadamente. En conclusión, no se observó una asociación estadísticamente significativa entre exposición al radón residencial y cáncer de pulmón; sin embargo, parece que con una muestra con una media de edad más elevada (tales como los participantes del estudio de casos y controles), el riesgo de cáncer de pulmón habría sido más alto.

Estudos de casos e controles mostram uma associação entre radônio residencial e câncer de pulmão. O artigo teve como objetivo investigar essa associação através de um estudo de coorte. Projetamos um estudo ambispectivo coorte, utilizando o mapa de radônio da Galícia, Espanha, com os controles obtidos de um estudo anterior de casos e controles. Os indivíduos foram recrutados entre 2002 e 2009. Os dados foram verificados para confirmar a incidência de câncer de pulmão e depois analisados com um modelo de regressão de Cox. Participaram um total de 2.127 indivíduos; foram identificados 24 casos de câncer de pulmão; 76,6% dos indivíduos foram obtidos através do mapa de radônio. O hazard ratio ajustado era 1,2 (IC95%: 0,5-2,8) para a categoria de indivíduos expostos a 50Bq/m3 ou mais. O risco aumentou quando os indivíduos do estudo de casos e controles foram analisados separadamente. Em conclusão, não foi observada associação estatisticamente significativa entre exposição ao radônio residencial e câncer de pulmão; entretanto, parece que com uma amostra com mediana de idade mais elevada (tais como os participantes do estudo de casos e controles), o risco de câncer de pulmão teria sido mais alto.