Regional Inequalities in Lung Cancer Mortality in Belgium at the Beginning of the 21st Century: The Contribution of Individual and Area-Level Socioeconomic Status and Industrial Exposure

Socio-economic inequalities in lung cancer mortality in Spain: a nation-wide study using area-based deprivation

BACKGROUND

Lung cancer is the main cause of cancer mortality worldwide and in Spain. Several previous studies have documented socio-economic inequalities in lung cancer mortality but these have focused on specific provinces or cities. The goal of this study was to describe lung cancer mortality in Spain by sex as a function of socio-economic deprivation.

METHODS

We analysed all registered deaths from lung cancer during the period 2011-2017 in Spain. Mortality data was obtained from the National Institute of Statistics, and socio-economic level was measured with the small-area deprivation index developed by the Spanish Society of Epidemiology, with the census tract of residence at the time of death as the unit of analysis. We computed crude and age-standardized rates per 100,000 inhabitants by sex, deprivation quintile, and type of municipality (rural, semi-rural, urban) considering the 2013 European standard population (ASR-E). We further calculated ASR-E ratios between the most deprived (Q5) and the least deprived (Q1) areas and mapped census tract smoothed standardized lung cancer mortality ratios by sex.

RESULTS

We observed 148,425 lung cancer deaths (80.7% in men), with 73.5 deaths per 100,000 men and 17.1 deaths per 100,000 women. Deaths from lung cancer in men were five times more frequent than in women (ASR-E ratio = 5.3). Women residing in the least deprived areas had higher mortality from lung cancer (ASR-E = 22.2), compared to women residing in the most deprived areas (ASR-E = 13.2), with a clear gradient among the quintiles of deprivation. For men, this pattern was reversed, with the highest mortality occurring in areas of lower socio-economic level (ASR-E = 99.0 in Q5 vs. ASR-E = 86.6 in Q1). These socio-economic inequalities remained fairly stable over time and across urban and rural areas.

CONCLUSIONS

Socio-economic status is strongly related to lung cancer mortality, showing opposite patterns in men and women, such that mortality is highest in women residing in the least deprived areas and men residing in the most deprived areas. Systematic surveillance of lung cancer mortality by socio-economic status may facilitate the assessment of public health interventions aimed at mitigating cancer inequalities in Spain.

Neighborhood disadvantage is associated with KRAS-mutated non-small cell lung cancer risk

PURPOSE

It remains unclear why individuals living in disadvantaged neighborhoods have shorter non-small cell lung cancer (NSCLC) survival. It is possible that living in these deprived areas is linked with increased risk of developing aggressive NSCLC biology. Here, we explored the association of somatic KRAS mutations, which are associated with shorter survival in NSCLC patients, and 11 definitions of neighborhood disadvantage spanning socioeconomic and structural environmental elements.

METHODS

We analyzed data from 429 NSCLC patients treated at a Comprehensive Cancer Center from 2015 to 2018. Data were abstracted from medical records and each patient's home address was used to assign publicly available indices of neighborhood disadvantage. Prevalence Ratios (PRs) for the presence of somatic KRAS mutations were estimated using modified Poisson regression models adjusted for age, sex, smoking status, race/ethnicity, educational attainment, cancer stage, and histology.

RESULTS

In the NSCLC cohort, 29% had KRAS mutation-positive tumors. We found that five deprivation indices of socioeconomic disadvantage were associated with KRAS mutation. A one decile increase in several of these socioeconomic disadvantage indices was associated with a 1.06 to 1.14 increased risk of KRAS mutation. Measures of built structural environment were not associated with KRAS mutation status.

CONCLUSION

Socioeconomic disadvantage at the neighborhood level is associated with higher risk of KRAS mutation while disadvantage related to built environmental structural measures was inversely associated. Our results indicate not only that neighborhood disadvantage may contribute to aggressive NSCLC biology, but the pathways linking biology to disadvantage are likely operating through socioeconomic-related stress.

Preschool Minority Children's Persian Vocabulary Development: A Language Sample Analysis

This study linked background TV and socioeconomic status (SES) to minority children’s Persian vocabulary development. To this end, 80 Iranian preschool children (aged 5–6 years old) from two minority groups of Arabs and Turks were selected using stratified random sampling. They were simultaneous bilinguals, i.e., their mother tongue was either Arabic or Azari and their first language was Persian. Language sample analysis (LSA) was used to measure vocabulary development through a 15-min interview by language experts (PhD in applied linguistics). The LSA measures included total number of utterances (TNU), total number of words (TNW), total number of new words (NDW), and mean length of utterance (MLU). A series of independent-samples t test, paired-samples t test, and repeated measures MANOVA tests were ran to examine data. Results showed significant improvements in children’s vocabulary scores from pretest to posttest for all children. In addition, high-SES children scored higher on the vocabulary measures in pretest and posttest. Moreover, background TV was associated with higher means in the TNW and the NDW in groups. The researchers concluded that background TV may be related to higher vocabulary scores in low-SES families as it may compensate for some linguistics gaps in these families including lower amount of child-parent interaction, play, and parents’ level of literacy.

MicroRNA-106a-5p promotes the proliferation, autophagy and migration of lung adenocarcinoma cells by targeting LKB1/AMPK

It has previously been reported that lung cancer has the highest morbidity and mortality rate worldwide; however, the pathogenesis underlying lung cancer has not been fully elucidated. The aim of the present was primarily to assess the influence of microRNA (miR)-106a-5p on the biological behaviors of lung cancer cells. In the present study, bioinformatics analysis was used to analyze the expression characteristics of miR-106a-5p and its relationship with the prognosis of patients with lung adenocarcinoma (LUAD) in The Cancer Genome Atlas. A dual luciferase reporter assay was performed to verify the binding of miR-106a-5p and liver kinase B1 (LKB1). The Cell Counting Kit-8, colony formation and Transwell assays were utilized to detect cell viability, proliferation and migration, respectively. Protein and RNA expression levels were examined by western blotting and reverse transcription-quantitative PCR analysis, respectively. It was observed that miR-106a-5p was highly expressed in LUAD and associated with poor prognosis. miR-106a-5p promoted the proliferation and migration of LUAD cells, and inhibited autophagy. By contrast, LKB1 inhibited cell proliferation and migration, promoted autophagy and blocked the cancer-promoting effects of miR-106a-5p. Overexpression of miR-106a-5p inhibited the phosphorylation of AMP-activated protein kinase (AMPK) and tuberin (TSC2), and promoted the phosphorylation of mTOR. By contrast, overexpression of LKB1 blocked the promotion of mTOR phosphorylation, and the inhibition of AMPK and TSC2 phosphorylation caused by miR-106a-5p. In summary, the results of the present study indicated that miR-106a-5p regulated the phosphorylation of the AMPK pathway by targeting LKB1, and was involved in the proliferation, migration and autophagy of LUAD cells.

Health inequality: a longitudinal study on geographic variations in lung cancer incidence and mortality in Taiwan

Background

This study is aimed toward an analysis of the variations in lung cancer incidence and mortality, adjusted by population factors (age, gender, and year), between administrative areas.

Methods

This is a retrospective study, using 2005–2014 data in each administrative area from the Taiwan Cancer Registry database organized by the Health Promotion Administration. The yearly age-standardized (overall) and crude (stratified by gender and age) incidence/mortality (and their growth rates) for each administrative area were collected and calculated. We used a mixed model to analyze the repeated measurements of yearly incidence and mortality rates and used general linear regression to analyze their growth rates.

Results

It was found that male and elderly populations had significantly higher lung cancer incidence and mortality in Taiwan. After adjusting for gender, age, and calendar year, there were no significant variations in incidence among the administrative areas, while the mortality in Yilan County was significantly higher than that in Taipei City (the capital city of Taiwan). On the other hand, the incidence in the female and younger population and mortality growth rates were higher. The incidence growth rate in Keelung City was significantly lower than that in Taipei City, while there were no significant variations in mortality growth rate among administrative areas.

Conclusions

This study found an inequality in the lung cancer burden among cities in Taiwan, which can serve as the basis for future resource allocations for lung cancer prevention and treatment in Taiwan.

Environmental Justice in Industrially Contaminated Sites. A Review of Scientific Evidence in the WHO European Region

In the WHO European Region the topic of contaminated sites is considered a priority among environment and health themes. Communities living in or close to contaminated sites tend to be characterized by a high prevalence of ethnic minorities and by an unfavorable socioeconomic status so rising issues of environmental justice. A structured review was undertaken to describe the contents of original scientific studies analyzing distributive and procedural justice in industrially contaminated sites carried out in the WHO European Region in the period 2010⁻2017. A systematic search of the literature was performed. In total, 14 articles were identified. Wherever assessments on environmental inequalities were carried out, an overburden of socioeconomic deprivation or vulnerability, with very few exemptions, was observed. The combined effects of environmental and socioeconomic pressures on health were rarely addressed. Results show that the studies on environmental and health inequalities and mechanisms of their generation in areas affected by industrially contaminated sites in the WHO European Region are in their early stages, with exemption of UK. Future efforts should be directed to improve study strategies with national and local assessments in order to provide evidence for equity-oriented interventions to reduce environmental exposure and related health risks caused by industrial contamination.

Rural dwellers are less likely to survive cancer - An international review and meta-analysis

BACKGROUND

Existing research from several countries has suggested that rural-dwellers may have poorer cancer survival than urban-dwellers. However, to date, the global literature has not been systematically reviewed to determine whether a rural cancer survival disadvantage is a global phenomenon.

METHODS

Medline, CINAHL, and EMBASE were searched for studies comparing rural and urban cancer survival. At least two authors independently screened and selected studies. We included epidemiological studies comparing cancer survival between urban and rural residents (however defined) that also took socioeconomic status into account. A meta-analysis was conducted using 11 studies with binary rural:urban classifications to determine the magnitude and direction of the association between rurality and differences in cancer survival. The mechanisms for urban-rural cancer survival differences reported were narratively synthesised in all 39 studies.

FINDINGS

39 studies were included in this review. All were retrospective observational studies conducted in developed countries. Rural-dwellers were significantly more likely to die when they developed cancer compared to urban-dwellers (HR 1.05 (95% CI 1.02 - 1.07). Potential mechanisms were aggregated into an ecological model under the following themes: Patient Level Characteristics; Institutions; Community, Culture and Environment; Policy and Service Organization.

INTERPRETATION

Rural residents were 5% less likely to survive cancer. This effect was consistently observed across studies conducted in various geographical regions and using multiple definitions of rurality. High quality mixed-methods research is required to comprehensively evaluate the underlying factors. We have proposed an ecological model to provide a coherent framework for future explanatory research.

FUNDING

None.

Effect of socioeconomic status on stage at diagnosis of lung cancer in a hospital-based multicenter retrospective clinical epidemiological study in China, 2005-2014

There is inconsistent evidence of associations between socioeconomic status (SES) and lung cancer stage in non-Chinese populations up to now. We set out to determine how SES affects stage at diagnosis at both individual and area levels, from a hospital-based multicenter 10-year (2005-2014) retrospective clinical epidemiological study of 7184 primary lung cancer patients in mainland China. Individual-level SES data were measured based on two indicators from case report forms of the study: an individual's education and occupation. Seven census indicator variables were used as surrogates for the area-level SES with principal component analysis (PCA). Multivariate analysis was undertaken using binary logistic regressions and multinomial logit model to describe the association and explore the effect across tertiles on stage after adjusting for demographic variables. There was a significant stepwise gradient of effect across different stages in the highest tertile of area-level SES, comparing with the lowest tertile of area-level SES (ORs, 0.77, 0.67, and 0.29 for stage II, III, and IV). Patients with higher education were less likely to have stage IV lung cancer, comparing with the illiterate group (ORs, 0.52, 0.63, 0.71, 0.64 for primary school, middle school, high school, college degree or above subgroup, respectively). Findings suggest that the most socioeconomically deprived areas may be associated with a higher risk of advanced-stage lung cancer, and increasing educational level may be correlated with a lower risk to be diagnosed at advanced stage in both men and women.

Evolution of educational inequalities in site-specific cancer mortality among Belgian men between the 1990s and 2000s using a "fundamental cause" perspective

BACKGROUND

According to the "fundamental cause" theory, emerging knowledge on health-enhancing behaviours and technologies results in health disparities. This study aims to assess (trends in) educational inequalities in site-specific cancer mortality in Belgian men in the 1990s and the 2000s using this framework.

METHODS

Data were derived from record linkage between the Belgian censuses of 1991 and 2001 and register data on mortality. The study population comprised all Belgian men aged 50-79 years during follow-up. Both absolute and relative inequality measures have been calculated.

RESULTS

Despite an overall downward trend in cancer mortality, educational differences are observed for the majority of cancer sites in the 2000s. Generally, inequalities are largest for mortality from preventable cancers. Trends over time in inequalities are rather stable compared with the 1990s.

CONCLUSIONS

Educational differences in site-specific cancer mortality persist in the 2000s in Belgium, mainly for cancers related to behavioural change and medical interventions. Policy efforts focussing on behavioural change and healthcare utilization remain crucial in order to tackle these increasing inequalities.

Using self-reported data on the social determinants of health in primary care to identify cancer screening disparities: opportunities and challenges

Background

Data on the social determinants of health can help primary care practices target improvement efforts, yet relevant data are rarely available. Our family practice located in Toronto, Ontario routinely collects patient-level sociodemographic data via a pilot-tested survey developed by a multi-organizational steering committee. We sought to use these data to assess the relationship between the social determinants and colorectal, cervical and breast cancer screening, and to describe the opportunities and challenges of using data on social determinants from a self-administered patient survey.

Methods

Patients of the family practice eligible for at least one of the three cancer screening types, based on age and screening guidelines as of June 30, 2015 and who had answered at least one question on a socio-demographic survey were included in the study. We linked self-reported data from the sociodemographic survey conducted in the waiting room with patients’ electronic medical record data and cancer screening records. We created an individual-level income variable (low-income cut-off) that defined a poverty threshold and took household size into account. The sociodemographic characteristics of patients who were overdue for screening were compared to those who were up-to-date for screening for each cancer type using chi-squared tests.

Results

We analysed data for 5766 patients for whom we had survey data. Survey participants had significantly higher screening rates (72.9, 78.7, 74.4% for colorectal, cervical and breast cancer screening respectively) than the 13, 036 patients for whom we did not have survey data (59.2, 65.3, 58.9% respectively). Foreign-born patients were significantly more likely to be up-to-date on colorectal screening than their Canadian-born peers but showed no significant differences in breast or cervical cancer screening. We found a significant association between the low-income cut-off variable and cancer screening; neighbourhood income quintile was not significantly associated with cancer screening. Housing status was also significantly associated with colorectal, cervical and breast cancer screening. There was a large amount of missing data for the low-income cut-off variable, approximately 25% across the three cohorts.

Conclusion

While we were able to show that neighbourhood income might under-estimate income-related disparities in screening, individual-level income was also the most challenging variable to collect. Future work in this area should target the income disparity in cancer screening and simultaneously explore how best to collect measures of poverty.

Electronic supplementary material

The online version of this article (doi:10.1186/s12875-017-0599-z) contains supplementary material, which is available to authorized users.

Carboxamide analog ITR-284 evokes apoptosis and inhibits migration ability in human lung adenocarcinoma A549 cells

Lung adenocarcinoma is the most common type of lung cancer and found in both smokers and non-smokers, but the treatment of lung cancer is limited. ITR-284 has been shown to be a potent carboxamide-derived anticancer agent and to induce apoptosis in leukemia and colon cancer cells. However, little is known whether ITR-284 has anticancer activity in human lung adenocarcinoma cells through induction of apoptosis and suppression of migration in vitro. We showed that ITR-284 inhibited human lung cancer A549 cells using the thiazolyl blue tetrazolium bromide (MTT) assay and evoked apoptosis via the cell cycle distribution at S phase arrest. After treatment with 20 nM ITR-284 for 24 h, apoptotic cells were induced and detected by Annexin V-FITC/PI staining. The production of reactive oxygen species (ROS) was dose-dependently increased in A549 cells caused by ITR-284. The results from immunoblotting analysis showed an elevation of protein levels of p53 and phosphorylation of p53 in A549 cells prior to ITR-284 exposure. Additionally, apoptosis-associated proteins such as Bax, cleaved caspase-3 and cleaved PARP were upregulated after ITR-284 treatment. By wound healing assay, low concentrations (1-5 nM) of ITR-284 exerted a greater effect on inhibition of A549 cell migration. The protein levels of E-cadherin and vimentin, which are the epithelial-mesenchymal transition (EMT) markers, were modulated in ITR-284-treated cells assessed by western blot analysis. Taken together, our data suggest that ITR-284 may be an effective anticancer agent for treating lung adenocarcinoma.

The geographic pattern of Belgian mortality: can socio-economic characteristics explain area differences?

Background

Country averages for health outcomes hide important within-country variations. This paper probes into the geographic Belgian pattern of all-cause mortality and wishes to investigate the contribution of individual and area socio-economic characteristics to geographic mortality differences in men aged 45–64 during the period 2001–2011.

Methods

Data originate from a linkage between the Belgian census of 2001 and register data on mortality and emigration during the period 2001–2011. Mortality rate ratios (MRRs) are estimated for districts and sub-districts compared to the Belgian average mortality level using Poisson regression modelling. Individual socio-economic position (SEP) indicators are added to examine the impact of these characteristics on the observed geographic pattern. In order to scrutinize the contribution of area-level socio-economic characteristics, random intercepts Poisson modelling is performed with predictors at the individual and the sub-district level. Random intercepts and slopes models are fitted to explore variability of individual-level SEP effects.

Results

All-cause MRRs for middle-aged Belgian men are higher in the geographic areas of the Walloon region and the Brussels-Capital Region (BCR) compared to those in the Flemish region. The highest MRRs are observed in the inner city of the BCR and in several Walloon cities. Their disadvantage can partially be explained by the lower individual SEP of men living in these areas. Similarly, the relatively low MRRs observed in the districts of Halle-Vilvoorde, Arlon and Virton can be related to the higher individual SEP. Among the area-level characteristics, both the percentage of men employed and the percentage of labourers in a sub-district have a protective effect on the individual MRR, regardless of individual SEP. Variability in individual-level SEP effects is limited.

Conclusions

Individual SEP partly explains the observed mortality gap in Belgium for some areas. The percentage of men employed and the percentage of labourers in a sub-district have an additional effect on the individual MRR aside from that of individual SEP. However, these socio-economic factors cannot explain all of the observed differences. Other mechanisms such as public health policy, cultural habits and environmental influences contribute to the observed geographic pattern in all-cause mortality among middle-aged men.

Electronic supplementary material

The online version of this article (doi:10.1186/s13690-016-0135-y) contains supplementary material, which is available to authorized users.