Clinical Significance of Symptoms in Smokers with Preserved Pulmonary Function

Currently, the diagnosis of chronic obstructive pulmonary disease (COPD) requires a ratio of forced expiratory volume in 1 second (FEV1) to forced vital capacity (FVC) of less than 0.70 as assessed by spirometry after bronchodilator use. However, many smokers who do not meet this definition have respiratory symptoms

Prevalence of Suspected Nonalcoholic Fatty Liver Disease in Hispanic/Latino Individuals Differs by Heritage

Non-alcoholic fatty liver disease (NAFLD) was shown to disproportionally affect Hispanic persons. We examined the prevalence of suspected NAFLD in Hispanic/Latino persons with diverse backgrounds

Consistency and precision of cancer reporting in a multiwave national panel survey

Abstract Background Many epidemiological studies rely on self-reported information, the accuracy of which is critical for unbiased estimates of population health. Previously, accuracy has been analyzed by comparing self-reports to other sources, such as cancer registries. Cancer is believed to be a well-reported condition. This paper uses novel panel data to test the consistency of cancer reports for respondents with repeated self-reports. Methods Data come from 978 adults who reported having been diagnosed with cancer in at least one of four waves of the Panel Study of Income Dynamics, 1999-2005. Consistency of cancer occurrence reports and precision of timing of onset were studied as a function of individual and cancer-related characteristics using logistic and ordered logistic models. Results Almost 30% of respondents gave inconsistent cancer reports, meaning they said they never had cancer after having said they did have cancer in a previous interview; 50% reported the year of diagnosis with a discrepancy of two or more years. More recent cancers were reported with a higher consistency and timing precision; cervical cancer was reported more inaccurately than other cancer types. Demographic and socio-economic factors were only weak predictors of reporting quality. Conclusions Results suggest that retrospective reports of cancer contain significant measurement error. The errors, however, are fairly random across different social groups, meaning that the results based on the data are not systematically biased by socio-economic factors. Even for health events as salient as cancer, researchers should exercise caution about the presumed accuracy of self-reports, especially if the timing of diagnosis is an important covariate.http://deepblue.lib.umich.edu/bitstream/2027.42/112656/1/12963_2010_Article_108.pd

Common Genetic Polymorphisms Influence Blood Biomarker Measurements in COPD

Implementing precision medicine for complex diseases such as chronic obstructive lung disease (COPD) will require extensive use of biomarkers and an in-depth understanding of how genetic, epigenetic, and environmental variations contribute to phenotypic diversity and disease progression. A meta-analysis from two large cohorts of current and former smokers with and without COPD [SPIROMICS (N = 750); COPDGene (N = 590)] was used to identify single nucleotide polymorphisms (SNPs) associated with measurement of 88 blood proteins (protein quantitative trait loci; pQTLs). PQTLs consistently replicated between the two cohorts. Features of pQTLs were compared to previously reported expression QTLs (eQTLs). Inference of causal relations of pQTL genotypes, biomarker measurements, and four clinical COPD phenotypes (airflow obstruction, emphysema, exacerbation history, and chronic bronchitis) were explored using conditional independence tests. We identified 527 highly significant (p 10% of measured variation in 13 protein biomarkers, with a single SNP (rs7041; p = 10−392) explaining 71%-75% of the measured variation in vitamin D binding protein (gene = GC). Some of these pQTLs [e.g., pQTLs for VDBP, sRAGE (gene = AGER), surfactant protein D (gene = SFTPD), and TNFRSF10C] have been previously associated with COPD phenotypes. Most pQTLs were local (cis), but distant (trans) pQTL SNPs in the ABO blood group locus were the top pQTL SNPs for five proteins. The inclusion of pQTL SNPs improved the clinical predictive value for the established association of sRAGE and emphysema, and the explanation of variance (R2) for emphysema improved from 0.3 to 0.4 when the pQTL SNP was included in the model along with clinical covariates. Causal modeling provided insight into specific pQTL-disease relationships for airflow obstruction and emphysema. In conclusion, given the frequency of highly significant local pQTLs, the large amount of variance potentially explained by pQTL, and the differences observed between pQTLs and eQTLs SNPs, we recommend that protein biomarker-disease association studies take into account the potential effect of common local SNPs and that pQTLs be integrated along with eQTLs to uncover disease mechanisms. Large-scale blood biomarker studies would also benefit from close attention to the ABO blood group

Factor structure of the Perceived Stress Scale-10 (PSS) across English and Spanish language responders in the HCHS/SOL Sociocultural Ancillary Study.

Despite widespread use, psychometric investigation of both original English and translated Spanish versions of the 10-item Perceived Stress Scale (PSS; Cohen, Kamarck, & Mermelstein, 1983) has been limited among the U.S. Hispanic/Latino population. The present study examined the factor structure, factorial invariance, and reliability and validity of PSS scores from English and Spanish versions using data from 5,176 Hispanics/Latinos who participated in the Hispanic Community Health Study/Study of Latinos Sociocultural Ancillary Study. Total sample and language multigroup confirmatory factor analyses supported a bi-factor model with all 10 PSS items loading on a general perceived stress factor, and the four reverse worded items also loading on a reverse worded factor. Internal consistency ranged from .68-.78 and it was indicated that reliable variance exists beyond the general perceived stress factor. The model displayed configural, metric, scalar, and residual invariance across language groups. Convergent validity analyses indicated that both the general perceived stress factor and the reverse worded factor were related to scores of depression, anxiety, and anger in the expected directions. The reverse worded factor added to the validity of the PSS beyond the general perceived stress factor. The total computed score of the PSS can be recommended for use with Hispanics/Latinos in the U.S. that complete the measure in English or Spanish and the reverse worded factor can enhance prediction

Poverty in Europe and the USA: Exchanging Official Measurement Methods

Official poverty methodologies differ from other poverty measurement methods in the sense that the official ones are more often used as a benchmark to develop new policies as well as to evaluate the performance of existing programs. Europe has the tradition and the practice to use relative poverty as “official” poverty estimates (Common Laeken indicators); the USA use an objective method to estimate official poverty (Orshansky indicator). Although related, each approach portrays different dimensions of poverty. In this study we compare the official poverty methodologies of the USA and EU by applying them on datasets of both countries. Using the harmonized European Community Household Panel (ECHP) for the EU and the Panel Study on Income Dynamics (PSID) for the USA, we compare poverty trends in the USA and EU in relative and absolute terms on a national level as well as for various subgroups of the populations. Additionally, we use the panel dimension of the data to analyze individual poverty dynamics. We find considerable differences between the estimates based on Laeken indicators and the estimates based on an Orshansky type of technology. It was expected that in general Orshansky generates lower poverty estimates than the Laeken indicators. However, it is puzzling to find that a.) these differences are less systematic than expected and b.) these differences are not constant over time and in some cases even have the reverse sign. These findings point to the desirability of involving both poverty concepts into (official) poverty assessments