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INTRODUCTION: A twice-daily single inhaler triple therapy consisting of budesonide/glycopyrrolate/formoterol fumarate (BGF) was approved by the US Food and Drug Administration (FDA) in July 2020 as a maintenance treatment for patients with chronic obstructive pulmonary disease (COPD). The objective of this AURA study is to describe patient characteristics, exacerbation and treatment history, and healthcare resource utilization (HCRU) before BGF initiation to better inform treatment decisions for prescribers. METHODS: This retrospective cohort study leveraged data of all payer types from IQVIA's Longitudinal Prescription Data (LRx) linked to Medical Data (Dx). Patients with COPD who had ⩾1 LRx claim for BGF between 1 October 2020 and 30 September 2021 were included. The date of first BGF claim was the index date. Patient demographic and clinical characteristics, history of COPD exacerbation or related event, treatment history, and HCRU were assessed during the 12 months before index (baseline). RESULTS: We identified 30,339 patients with COPD initiating BGF (mean age: 68.2 years; 57.1% female; 67.6% Medicare). Unspecified COPD (J44.9; 74.0%) was the most commonly coded COPD phenotype. The most prevalent respiratory conditions/symptoms were dyspnea (50.8%), lower respiratory tract infection (25.3%), and sleep apnea (19.0%). Uncomplicated hypertension (58.8%), dyslipidemia (43.9%), cardiovascular disease (41.4%), and heart failure (19.9%) were the most prevalent nonrespiratory conditions. During the 12-month baseline, 57.9% of patients had evidence of a COPD exacerbation or related event, and 14.9% had ⩾1 COPD-related emergency department (ED) visit; 21.0% of patients had evidence of prior triple therapy use, while 54.3% had ⩾1 oral corticosteroid (OCS) fill. Among OCS users, 29.9% had cumulative exposures >1000 mg [median [Q1-Q3] exposure: 520 (260-1183) mg]. CONCLUSION: This real-world data analysis indicates that BGF is being initiated in patients with COPD experiencing symptoms and exacerbations despite current therapy, and among patients who have various chronic comorbidities, most often cardiopulmonary-related.
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Broncodilatadores , Doença Pulmonar Obstrutiva Crônica , Idoso , Humanos , Feminino , Estados Unidos , Masculino , Fumarato de Formoterol , Glicopirrolato , Estudos Retrospectivos , Combinação de Medicamentos , Inaladores Dosimetrados , Medicare , Budesonida , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico , Administração por InalaçãoRESUMO
BACKGROUND: Real-world evidence for brigatinib, a next-generation anaplastic lymphoma kinase-tyrosine kinase inhibitor (ALK-TKI) used in ALK-rearranged non-small cell lung cancer, is scarce. This retrospective study evaluated real-world brigatinib utilization in the US post other ALK-TKIs. MATERIALS AND METHODS: Adults with ≥1 brigatinib claim (index date) between 1 April 2017 and 30 September 2020 in the IQVIA longitudinal pharmacy claims database were followed until dose reduction, discontinuation, or end of follow-up. Patients had ≥12 months pre- and ≥1-month post-index observations. RESULTS: A total of 413 patients treated with brigatinib were analyzed. Over 80% received ≥1 prior ALK-TKI; alectinib and crizotinib were the most common (58.8% and 51.3% patients, respectively). The median follow-up was 8.4 months. The median time to treatment discontinuation (TTD) for brigatinib was 10.3 months (95% CI, 8.2-15.0), with 45% remaining on therapy at 12 months. The TTD was shortest (~8 months) in patients receiving both crizotinib and alectinib and longest in patients who received alectinib only prior to brigatinib (11.8 months). Adherence was high, with 92.7% of patients having a medication possession ratio of >80%. The mean dose compliance score was 1.0. Most patients reached the brigatinib dose of 180 mg/day (77%); 13.2% of patients had a dose reduction, with 89.3% and 84.6% continuing 180 mg/day therapy at 3 and 6 months, respectively. CONCLUSIONS: Brigatinib appears to be effective and well-tolerated in the real-world ALK+ NSCLC population in the US, showing benefit in patients after a next-generation ALK-TKI. Notably, dose reduction rates appeared markedly less than those seen in trials when most trial-related dose reductions were for asymptomatic laboratory abnormalities.
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Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Adulto , Quinase do Linfoma Anaplásico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Crizotinibe/uso terapêutico , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/patologia , Compostos Organofosforados , Inibidores de Proteínas Quinases/efeitos adversos , Pirimidinas , Estudos Retrospectivos , Estados UnidosRESUMO
AIMS: Ocular toxicities are common adverse events (AEs) associated with anticancer agents. There is a paucity of data documenting their impact on patient care. This study assessed the clinical and economic burden of corneal AEs and related symptoms (collectively termed corneal AEs) in patients receiving multiple myeloma (MM) treatment. MATERIALS AND METHODS: Adults with a newly diagnosed MM (MM cohort) were identified from PharMetrics Plus, a US insurance claims database. Incidence, outpatient (OP) care, emergency department (ED) visits, hospitalizations, and costs were assessed for corneal AEs of interest: keratopathy/keratitis, blurred vision/decreased acuity, dry eye, eye pain, and photophobia. Incidence of new corneal AEs, healthcare resource utilization (HCRU), corneal AE-related HCRU, and costs were assessed and benchmarked against a hematology cohort of patients. RESULTS: The MM cohort included 2,120 patients with a median follow-up of 734.5 days. Overall, 11.7% of patients in the MM cohort and 7.4% in the hematology cohort had ≥1 corneal AE of interest. In the MM cohort, dry eye (6.1%), blurred vision/decreased acuity (3.4%), and keratopathy/keratitis (2.5%) were the most frequent. The overall median corneal AE-related per-patient-per-month (PPPM) cost was $27, predominantly contributed by OP care (median $19 PPPM). During follow-up, 4.8% of patients visited the ED, 3.6% were hospitalized, and 42.5% of patients visited an ophthalmologist/optometrist (â¼1.69 visits/year). Costs of these visits were negligible (median PPPM $19) compared to total all-cause costs (median PPPM $17,286). LIMITATIONS: The results can only be generalized to commercially insured and Medicare Advantage patients. Claims-based diagnosis of corneal AEs may underestimate true incidences. CONCLUSIONS: Corneal AEs were observed in â¼12% of patients in the MM cohort, the most common were keratopathy/keratitis, dry eye, and blurred vision. Most of them required only OP care. The clinical and economic burden for treating corneal AEs was low when compared with total all-cause or MM-related PPPM costs.
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Mieloma Múltiplo , Adulto , Idoso , Estudos de Coortes , Custos de Cuidados de Saúde , Humanos , Incidência , Medicare , Mieloma Múltiplo/tratamento farmacológico , Estudos Retrospectivos , Estados Unidos/epidemiologiaRESUMO
BACKGROUND/OBJECTIVES: Vaccination against herpes zoster (HZ) is an effective strategy in protecting the population against consequences of varicella zoster virus reactivation. Optimal immunogenicity with recombinant zoster vaccine (RZV) relies on completion of the 2-dose series within 2-6 months from the first dose. The objectives of this study were to estimate RZV completion rates and adherence with the recommended administration schedule in the general United States population aged at least 50 years and to evaluate factors influencing completion rates. METHODS: Longitudinal, open-source pharmacy and medical claims databases were analyzed for adults aged at least 50 years with a first RZV prescription filled between October 2017 and September 2019. The data were linked to Experian Marketing Services Consumer View data to obtain information regarding race. Completion rates and adherence were calculated overall and stratified according to claim source, age class, sex, and payer type. Logistic regression models were built for each subpopulation of interest to identify factors correlating with completion rates. RESULTS: Overall, cumulative completion rates were 70.41% and 81.80% at 6 and 12 months, respectively. Median time to second dose was approximately 4 months (4.08-5.13 months) and adherence 67.62%. Completion rates were lower in the medical claims database compared with the pharmacy claims database (48.98% vs. 73.23% at 6 months). Regression models confirmed that pharmacy claim was an independent factor for higher completion rates, while African American race and Medicaid status were associated with lower completion rates. Most comorbidities, including chronic obstructive pulmonary disease and type 2 diabetes mellitus, were associated with lower completion rates. CONCLUSION: Pharmacists contribute substantially to the overall high RZV completion rates in the United States. However, completion rates can be improved, especially in people receiving their first RZV dose at a physician's office. Future strategies should aim at lowering barriers to completing vaccination series in African Americans, Medicaid beneficiaries, and people with comorbidities.
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Diabetes Mellitus Tipo 2 , Vacina contra Herpes Zoster , Herpes Zoster , Farmácia , Adulto , Herpes Zoster/epidemiologia , Herpes Zoster/prevenção & controle , Humanos , Revisão da Utilização de Seguros , Estudos Retrospectivos , Estados Unidos , Vacinas SintéticasRESUMO
BACKGROUND: The risk for subsequent major cardiovascular (CV) events among patients with very high-risk (VHR) atherosclerotic CV disease (ASCVD) remains to be fully elucidated. HYPOTHESIS: We assessed the characteristics and major CV event rates of patients with VHR versus non-VHR ASCVD in a real-world setting in the United States (US), hypothesizing that patients with VHR ASCVD would have higher CV event rates. METHODS: This was a retrospective cohort study conducted from January 01, 2011, to June 30, 2018, in the US using the Prognos LDL-C database linked to the IQVIA PharMetrics Plus® database supplemented with the IQVIA prescription claims (Dx/LRx) databases. Patients were ≥18 years old and had ≥2 non-ancillary medical claims in the linked databases at least 30 days apart. The study was conducted in 2 stages: (1) identification of patients with ASCVD who met the definition of VHR ASCVD and a matched cohort of non-VHR ASCVD patients using the incidence density sampling (IDS) approach; (2) estimation of the occurrence of major CV events. RESULTS: Among patients with ≥1 major ASCVD event (N=147,679), most qualified as VHR ASCVD (79.5%). There were 115,460 patients each in IDS-matched VHR and non-VHR ASCVD cohorts. The composite myocardial infarction/ischemic stroke event rates in the VHR and non-VHR ASCVD cohorts were 8.04 (95% confidence interval [95% CI]: 7.87-8.22) and 0.82 (95% CI: 0.77-0.88) events per 100 patient-years, respectively, during the 1-year post-index period. CONCLUSIONS: Most patients with ≥1 previous major ASCVD event treated in real-world US clinical practice qualified as VHR ASCVD. Patients with VHR ASCVD had much higher rates of major CV events versus non-VHR ASCVD patients.
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Aterosclerose , Doenças Cardiovasculares , Acidente Vascular Cerebral , Adolescente , Aterosclerose/diagnóstico , Aterosclerose/epidemiologia , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Estudos de Coortes , Humanos , Estudos Retrospectivos , Medição de Risco , Estados Unidos/epidemiologiaRESUMO
OBJECTIVE: We assessed national- and state-level geographic variations among patients with a history of ≥1 major atherosclerotic cardiovascular disease (ASCVD) event in: (1) the proportion of patients with retrospectively identified 2018 American College of Cardiology/American Heart Association guideline very high-risk (VHR) ASCVD criteria; (2) utilization of guideline-directed lipid-lowering therapy (LLT); and (3) the proportion of patients with persistent low-density lipoprotein cholesterol (LDL-C) elevations despite statin and/or ezetimibe use. METHODS: A retrospective cohort study using the Prognos LDL-C database linked to IQVIA longitudinal medical and prescription claims databases. The study period was from January 01, 2011, to November 30, 2019 and the index period was from January 01, 2016, to November 30, 2019; the index date was defined as the most recent LDL-C test during the index period. The study included patients aged ≥18 years at index who had a measured LDL-C level during the index period and had ≥1 inpatient/outpatient claim for ASCVD during the 5-year pre-index period. RESULTS: Of patients with any ASCVD (N=4652,468), 1537,514 (33.1%) patients had ≥1 major ASCVD event. Among patients with ≥1 major ASCVD event, the VHR ASCVD criteria were retrospectively identified in 1139,018 (74.1%) patients; Hawaii had the highest (81.7%) and Colorado the lowest (65.0%) proportion of these patients. Nationally, 48.8% and 50.2% of patients with ≥1 major ASCVD event and retrospectively identified VHR ASCVD criteria, respectively, had current LLT use; Massachusetts and Colorado had the highest and lowest proportions, respectively. After standardizing for age and sex, 57.3% and 58.8% of patients with ≥1 major ASCVD event and retrospectively identified VHR ASCVD criteria, respectively, had LDL-C ≥70 mg/dL (≥1.8 mmol/L) despite statin and/or ezetimibe use, with substantial state-level variations observed. CONCLUSIONS: The study highlights high rates of elevated LDL-C and pervasive underuse of LLT in health-insured patients with a history of major ASCVD events treated in the United States, with state-level geographic variations observed.
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Shingrix (Recombinant zoster vaccine, RZV) was approved in October 2017 in the United States (US) for the prevention of herpes zoster in adults aged 50 years and older. The vaccine is administered in two doses, with the second dose administration recommended between two and six months after the first dose. Examination of uptake and series completion is important to ensure appropriate use, especially at the time of vaccine introduction. This report provides demographic characteristics of patients receiving RZV between October 2017 and September 2019, first- and second-dose uptake, and a cumulative estimation of second-dose completion by month for US adults aged 50 years and older. Monthly uptake increased rapidly since October 2017; overall, 7,097,441 first doses of RZV were administered along with 4,277,636 second doses during the observed timeframe. Among people with an observed first-dose administration, 70% and 80% completed the two-dose series within six and 12 months post initial dose, respectively. This evidence suggests that RZV has rapidly been adopted by a large population in the US and most are following manufacturer or policy recommendations regarding series completion. Further analyses are needed to explore potential patient, provider, and policy-relevant characteristics associated with second-dose completion that could serve as targets for further improvement.
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Vacina contra Herpes Zoster , Herpes Zoster , Adulto , Idoso , Herpes Zoster/prevenção & controle , Herpesvirus Humano 3 , Humanos , Pessoa de Meia-Idade , Estados Unidos , Vacinas SintéticasRESUMO
The temporal variations of the airborne radon decay product dose rate and deposited radon decay product activities, as well as the within-house and house-to-house variations of radon concentrations, were evaluated through repeated field measurements. Long-term average radon and surface-deposited radon decay product concentrations were measured in 76 rooms of 38 houses. Temporal variation of radon, as well as airborne and surface-deposited radon decay products, were measured in 11 of the 38 houses during two different seasons. Environmental factors that have the potential to influence airborne dose rate and deposited radon decay products were also studied. Airborne dose rates were calculated from the unattached and attached potential alpha energy concentrations using two dosimetric models. For one model, the observed dose variations were 103%, 74%, 58%, and 60% for the total, house-to-house, within-house, and within-room temporal variations, respectively. For the other model, the dose variations were 100%, 66%, 61%, and 46%, respectively. Surface-deposited Po showed variations of 79%, 57%, 42%, and 48%, respectively. These substantial radon decay product concentration variations suggest that multiple locations and time-integrated measurements are needed to make an accurate assessment of the chronic radon-related doses in homes. Smoking was the environmental factor that had the largest temporal and spatial effect on airborne radon decay product dose rates.
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Poluentes Radioativos do Ar/análise , Poluição do Ar em Ambientes Fechados/análise , Habitação , Monitoramento de Radiação/métodos , Radônio/análise , Humanos , Doses de Radiação , Análise Espaço-TemporalRESUMO
BACKGROUND: Intra-articular injection of hyaluronic acid (HA) for knee osteoarthritis (OA) effectively reduces pain and delays total knee replacement (TKR) surgery; however, little is known about relative differences in clinical and cost outcomes among different HA products. OBJECTIVE: To compare disease-specific costs and risk of TKR among patients receiving different HA treatments in a commercially insured cohort of patients with knee OA in the USA. METHOD: Retrospective analyses using IMS Health's PharMetrics Plus Health Plan Claims Database were conducted by identifying knee OA patients with claims indicating initiation of HA treatment at an 'index date' during the selection period (2007-2010). Patients were required to be continuously enrolled in the database for 12 months preindex to 36 months postindex. A generalized linear model (GLM) with a gamma distribution and log-link function was used to model aggregate patient-based changes in disease-specific costs. A Cox proportional hazards model (PHM) was used to model the risk of TKR. Both multivariate models included covariates such as age, gender, comorbidities, and preindex healthcare costs. RESULTS: 50,389 patients with HA treatment for knee OA were identified. 18,217 (36.2%) patients were treated with HA products indicated for five injections per treatment course (Supartz and Hyalgan). The remainder were treated with HA products indicated for fewer than five injections per treatment course, with 20,518 patients (40.7%) receiving Synvisc; 6,263 (12.4%), Euflexxa; and 5,391 (10.7%), Orthovisc. Synvisc- and Orthovisc-injected patients had greater disease-specific costs compared to Supartz/Hyalgan (9.0%, p<0.0001 and 6.8%, p=0.0050, respectively). Hazard ratios (HRs) showed a significantly higher risk of TKR for patients receiving Synvisc compared to Supartz/Hyalgan (HR=1.069, p=0.0009). Patients treated with Supartz/Hyalgan, Euflexxa, and Orthovisc had longer delays to TKR than those treated with Synvisc. CONCLUSION: Analysis of administrative claims data provides real-world evidence that meaningful differences exist among some HA products in disease-specific cost and time to knee replacement surgery.
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The introduction of pertussis vaccination in the United States (US) in the 1940s has greatly reduced its burden. However, the incidence of pertussis is difficult to quantify, as many cases are not laboratory-confirmed or reported, particularly in adults. This study estimated pertussis incidence in a commercially insured US population aged <50 years. Data were extracted from IMS' PharMetrics Plus claims database for patients with a diagnosis of pertussis or cough illness using International Classification of Diseases (ICD-9) codes, a commercial outpatient laboratory database for patients with a pertussis laboratory test, and the Centers for Disease Control influenza surveillance database. US national pertussis incidence was projected using 3 methods: (1) diagnosed pertussis, defined as a claim for pertussis (ICD-9 033.0, 033.9, 484.3) during 2008-2013; (2) based on proxy pertussis predictive logistic regression models; (3) using the fraction of cough illness (ICD-9 033.0, 033.9, 484.3, 786.2, 466.0, 466.1, 487.1) attributed to laboratory-confirmed pertussis, estimated by time series linear regression models. Method 1 gave a projected annual incidence of diagnosed pertussis of 9/100,000, which was highest in those aged <1 year. Method 2 gave an average annual projected incidence of 21/100,000. Method 3 gave an overall regression-estimated weighted annual incidence of pertussis of 649/100,000, approximately 58-93 times higher than method 1 depending on the year. These estimations, which are consistent with considerable underreporting of pertussis in people aged <50 years and provide further evidence that the majority of cases go undetected, especially with increasing age, may aid in the development of public health programs to reduce pertussis burden.
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Coqueluche/epidemiologia , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Estados Unidos/epidemiologia , Adulto JovemRESUMO
OBJECTIVE: The goal was to examine the association between the New York State (NYS) upgraded child restraint law (UCRL) implemented in 2005 and the traffic injury rate among 4- to 6-year-old children in New York State. METHODS: A before/after comparison study of population-based, traffic injury rates for 4- to 6-year-old children, using 0- to 3-year-old children as a comparison group, was performed. The effects of UCRL on injury rates among 0- to 3-year-old and 4- to 6-year-old motor vehicle passengers were estimated by using monthly injury count data from the NYS Department of Motor Vehicles Accident Information System. RESULTS: Children 4 to 6 years of age experienced an 18% reduction in traffic injury rate (adjusted rate ratio [aRR]: 0.82 [95% confidence interval [CI]: 0.79-0.85]) after UCRL implementation, whereas the injury rate for children 0 to 3 years of age, who were not directly affected by the UCRL, did not change appreciably (aRR: 0.95 [95% CI: 0.90-0.99]). In Poisson regression analysis, the aRR for injury for 4- to 6-year-old children was 1.06 (95% CI: 0.92-1.22]) with adjustment for monthly child restraint use rates, which reveals that the significant reduction in the injury rate among 4- to 6-year-old children was mainly attributable to the 72% increase in the child restraint use rate after UCRL implementation (from 29% before UCRL implementation to 50% after implementation). CONCLUSIONS: This is the first study comparing traffic injury rates for booster seat-aged children before and after implementation of the booster seat law in a single state.
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Acidentes de Trânsito/legislação & jurisprudência , Acidentes de Trânsito/estatística & dados numéricos , Sistemas de Proteção para Crianças/normas , Ferimentos e Lesões/epidemiologia , Ferimentos e Lesões/prevenção & controle , Acidentes de Trânsito/prevenção & controle , Criança , Pré-Escolar , Humanos , Lactente , New YorkRESUMO
The quantitative relationships between radon gas concentration, the surface-deposited activities of various radon progeny, the airborne radon progeny dose rate, and various residential environmental factors were investigated through a Monte Carlo simulation study based on the extended Jacobi room model. Airborne dose rates were calculated from the unattached and attached potential alpha-energy concentrations (PAECs) using two dosimetric models. Surface-deposited (218)Po and (214)Po were significantly correlated with radon concentration, PAECs, and airborne dose rate (p-values <0.0001) in both non-smoking and smoking environments. However, in non-smoking environments, the deposited radon progeny were not highly correlated to the attached PAEC. In multiple linear regression analysis, natural logarithm transformation was performed for airborne dose rate as a dependent variable, as well as for radon and deposited (218)Po and (214)Po as predictors. In non-smoking environments, after adjusting for the effect of radon, deposited (214)Po was a significant positive predictor for one dose model (RR 1.46, 95% CI 1.27-1.67), while deposited (218)Po was a negative predictor for the other dose model (RR 0.90, 95% CI 0.83-0.98). In smoking environments, after adjusting for radon and room size, deposited (218)Po was a significant positive predictor for one dose model (RR 1.10, 95% CI 1.02-1.19), while a significant negative predictor for the other model (RR 0.90, 95% CI 0.85-0.95). After adjusting for radon and deposited (218)Po, significant increases of 1.14 (95% CI 1.03-1.27) and 1.13 (95% CI 1.05-1.22) in the mean dose rates were found for large room sizes relative to small room sizes in the different dose models.
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Poluentes Radioativos do Ar/análise , Poluição do Ar em Ambientes Fechados/análise , Produtos de Decaimento de Radônio/análise , Poluentes Radioativos do Ar/efeitos adversos , Poluição do Ar em Ambientes Fechados/efeitos adversos , Habitação , Humanos , Iowa , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/etiologia , Modelos Teóricos , Método de Monte Carlo , Neoplasias Induzidas por Radiação/epidemiologia , Neoplasias Induzidas por Radiação/etiologia , Polônio/efeitos adversos , Polônio/análise , Doses de Radiação , Radiometria/estatística & dados numéricos , Produtos de Decaimento de Radônio/efeitos adversos , Análise de Regressão , Propriedades de Superfície , VentilaçãoRESUMO
The quantitative relationships between radon gas concentration, the surface-deposited activities of various radon progeny, the airborne radon progeny dose rate, and various residential environmental factors were investigated through actual field measurements in 38 selected Iowa houses occupied by either smokers or nonsmokers. Airborne dose rate was calculated from unattached and attached potential alpha energy concentrations (PAECs) using two dosimetric models with different activity-size weighting factors. These models are labeled Pdose and Jdose, respectively. Surface-deposited 218Po and 214Po were found significantly correlated to radon, unattached PAEC, and both airborne dose rates (p < 0.0001) in nonsmoking environments. However, deposited 218Po was not significantly correlated to the above parameters in smoking environments. In multiple linear regression analysis, natural logarithm transformation was performed for airborne dose rate as the dependent variable, as well as for radon and deposited 218Po and 214Po as predictors. An interaction effect was found between deposited 214Po and an obstacle in front of the Retrospective Reconstruction Detector (RRD) in predicting dose rate (p = 0.049 and 0.058 for Pdose and Jdose, respectively) for nonsmoking environments. After adjusting for radon and deposited radon progeny effects, the presence of either cooking, usage of a fireplace, or usage of a ceiling fan significantly, or marginally significantly, reduced the Pdose to 0.65 (90% CI 0.42-0.996), 0.54 (90% CI 0.28-1.02), and 0.66 (90% CI 0.45-0.96), respectively. For Jdose, only the usage of a ceiling fan significantly reduced the dose rate to 0.57 (90% CI 0.39-0.85). In smoking environments, deposited 218Po was a significant negative predictor for Pdose (RR 0.68, 90% CI 0.55-0.84) after adjusting for long-term 222Rn and environmental factors. A significant decrease of 0.72 (90% CI 0.64-0.83) in the mean Pdose was noted, after adjusting for the radon and radon progeny effects and other environmental factors, for every 10 additional cigarettes smoked in the room. A significant increase of 1.71 in the mean Pdose was found for large room size relative to small room size (90% CI 1.08-2.79) after adjusting for the radon and radon progeny effects as well as other environmental factors. Fireplace usage was found to significantly increase the mean Pdose to 1.71 (90% CI 1.20-2.45) after adjusting for other factors.
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Poluentes Radioativos do Ar/análise , Poluição do Ar em Ambientes Fechados/análise , Neoplasias Pulmonares/etiologia , Produtos de Decaimento de Radônio , Radônio/análise , Relação Dose-Resposta à Radiação , Habitação , Humanos , Neoplasias Pulmonares/patologia , Doses de Radiação , Monitoramento de RadiaçãoRESUMO
A sample of commercially available, charcoal adsorption type, short-term radon detectors was blind tested under controlled laboratory conditions in order to obtain a "snapshot" of the accuracy and precision of the detectors. The results of the controlled exposures were then compared to a previous field study of the same type of commercially available radon detectors. Radon detectors, purchased from seven different commercial vendors, were exposed to a reference (222)Rn gas concentration at the U.S. Environmental Protection Agency's (EPA) Radon Chamber located at the Radiation and Indoor Environments National Laboratory in Las Vegas, Nevada. EPA Test 1 was performed under a controlled simulated field exposure paralleling, to the extent possible, the previous actual field exposure conditions. A second controlled exposure, EPA Test 2, was performed under a relatively steady state of (222)Rn gas concentration, at the same temperature, but a more moderate relative humidity. In the previous field setting evaluation of detectors, five out of six companies tested did not pass the accuracy guideline (all individual relative errors < or =25%) established during the EPA's former Radon Measurement Proficiency Program (EPA-RMPP). As compared to the field test, the detectors in this study generally exhibited better accuracy and precision. Not surprisingly, it appeared temporal fluctuations in radon concentrations and increased humidity had a negative influence on the accuracy and precision of detectors for some companies. The inability of three out of seven companies to meet former EPA-RMPP guidelines for accuracy, even under ideal exposure conditions (constant temperature, humidity, and radon concentration), highlights the importance of blind testing commercially available radon detectors. Furthermore, the consistent over-reporting or under-reporting trends in the overall results for all three tests suggest a potentially widespread systematic bias for the individual companies that merits further investigation. It is unknown if this one-time "snapshot" represents the overall reliability of commercially available charcoal-based radon detectors. Nonetheless, the findings suggest the need for improved vigilance to assure that the public can rely on commercially available radon detectors to make an informed decision whether or not to perform additional testing or to mitigate.
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Poluentes Radioativos do Ar/análise , Monitoramento de Radiação/instrumentação , Radônio/análise , Adsorção , Poluição do Ar em Ambientes Fechados/análise , Carvão Vegetal , Contagem de CintilaçãoRESUMO
We performed a comparison of commercially available short-term radon detectors in order to determine the accuracy and precision of the detectors under actual field conditions. We exposed fifteen radon detectors, under field conditions, from each of six companies to a reference radon concentration. Five of the six companies tested did not pass the U.S. Environmental Protection Agency's previously established accuracy guideline (all individual relative errors = 25%) and four of the six companies failed the EPA's precision guideline [coefficient of variation = 10% at 150 Bq m (4 pCi L)]. The findings suggest that the performances of commercially available radon detectors exposed under actual field conditions may not be as accurate or precise as those detectors available prior to the close of the EPA's National Radon Proficiency Program in 1998. It is unknown if this one-time "snap shot" represents the overall reliability of the accuracy and precision of commercially available radon detectors. Nonetheless, the findings suggest that additional double-blind testing of commercially available radon detectors under actual field conditions is warranted.
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Poluentes Radioativos do Ar/análise , Monitoramento de Radiação/instrumentação , Radiometria/instrumentação , Radônio/análise , Estados UnidosRESUMO
Radon flux rate from soil is one of the most important factors for the evaluation of environmental radon levels. The objective of our study is to make a rough estimation of the nationwide radon flux rate from soil in China. Considering the applicability to the large area and complex distribution of soil types in China, a simple model was established. To test the model, field measurements on radon flux rate totally in 47 points from different areas were carried out from spring to summer in 2003. Laboratory experiments of each soil sample on related soil properties, such as radium contents, water contents, soil dry bulk density and soil texture were performed simultaneously. Approximately 30% of the samples had very consistent calculated values with their measured values, their relative errors were less than 0.25. In spite of the large uncertainties in the model which is influenced by so many factors, the considerable validation of the model can be shown. Based on the discussion of distribution of the errors as well as the reasons causing the errors, a trial modification of the model was made. A modification function looked necessary when soil water content was <10%.