Choice of geographic unit influences socioeconomic inequalities in breast cancer survival

What can hospital emergency admissions prior to cancer diagnosis tell us about socio-economic inequalities in cancer diagnosis? Evidence from population-based data in England

BACKGROUND

More deprived cancer patients are at higher risk of Emergency Presentation (EP) with most studies pointing to lower symptom awareness and increased comorbidities to explain those patterns. With the example of colon cancer, we examine patterns of hospital emergency admissions (HEAs) history in the most and least deprived patients as a potential precursor of EP.

METHODS

We analysed the rates of hospital admissions and their admission codes (retrieved from Hospital Episode Statistics) in the two years preceding cancer diagnosis by sex, deprivation and route to diagnosis (EP, non-EP). To select the conditions (grouped admission codes) that best predict emergency admission, we adapted the purposeful variable selection to mixed-effects logistic regression.

RESULTS

Colon cancer patients diagnosed through EP had the highest number of HEAs than all the other routes to diagnosis, especially in the last 7 months before diagnosis. Most deprived patients had an overall higher rate and higher probability of HEA but fewer conditions associated with it.

CONCLUSIONS

Our findings point to higher use of emergency services for non-specific symptoms and conditions in the most deprived patients, preceding colon cancer diagnosis. Health system barriers may be a shared factor of socio-economic inequalities in EP and HEAs.

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.

Association between socioeconomic status and net survival after primary lung cancer surgery: a tertiary university hospital retrospective observational study in Japan

BACKGROUND

Inequalities in opportunities for primary lung cancer surgery due to socioeconomic status exist. We investigated whether socioeconomic inequalities exist in net survival after curative intent surgery at a tertiary university hospital, in Japan.

METHODS

Data from the hospital-based cancer registry on primary lung cancer patients who received lung resection between 2010 and 2018 were linked to the surgical dataset. An area deprivation index, calculated from small area statistics and ranked into tertiles based on Japan-wide distribution, was linked with the patient's address as a proxy measure for individual socioeconomic status. We estimated net survival of up to 5 years by deprivation tertiles. Socioeconomic inequalities in cancer survival were analyzed using an excess hazard model.

RESULTS

Of the 1039 patient-sample, advanced stage (Stage IIIA+) was more prevalent in the most deprived group (28.1%) than the least deprived group (18.0%). The 5-year net survival rates (95% confidence interval) from the least to the most deprived tertiles were 82.1% (76.2-86.6), 77.6% (70.8-83.0) and 71.4% (62.7-78.4), respectively. The sex- and age-adjusted excess hazard ratio of 5-year death was significantly higher in the most deprived group than the least deprived (excess hazard ratio = 1.64, 95% confidence interval: 1.09-2.47). The hazard ratio reduced toward null after additionally accounting for disease stage, suggesting that the advanced stage may explain the poor prognosis among the deprived group.

CONCLUSION

There was socioeconomic inequality in the net survival of patients who received curative intent surgery for primary lung cancer. The lower socioeconomic status group might be less likely to receive early curative surgery.

Effects of socioeconomic status on excess mortality in patients with multiple sclerosis in France: A retrospective observational cohort study

Background

The effects of socio-economic status on mortality in patients with multiple sclerosis is not well known. The objective was to examine mortality due to multiple sclerosis according to socio-economic status.

Methods

A retrospective observational cohort design was used with recruitment from 18 French multiple sclerosis expert centers participating in the Observatoire Français de la Sclérose en Plaques. All patients lived in metropolitan France and had a definite or probable diagnosis of multiple sclerosis according to either Poser or McDonald criteria with an onset of disease between 1960 and 2015. Initial phenotype was either relapsing-onset or primary progressive onset. Vital status was updated on January 1st 2016. Socio-economic status was measured by an ecological index, the European Deprivation Index and was attributed to each patient according to their home address. Excess death rates were studied according to socio-economic status using additive excess hazard models with multidimensional penalised splines. The initial hypothesis was a potential socio-economic gradient in excess mortality.

Findings

A total of 34,169 multiple sclerosis patients were included (88% relapsing onset (n = 30,083), 12% progressive onset (n = 4086)), female/male sex ratio 2.7 for relapsing-onset and 1.3 for progressive-onset). Mean age at disease onset was 31.6 (SD = 9.8) for relapsing-onset and 42.7 (SD = 10.8) for progressive-onset. At the end of follow-up, 1849 patients had died (4.4% for relapsing-onset (n = 1311) and 13.2% for progressive-onset (n = 538)). A socio-economic gradient was found for relapsing-onset patients; more deprived patients had a greater excess death rate. At thirty years of disease duration and a year of onset of symptoms of 1980, survival probability difference (or deprivation gap) between less deprived relapsing-onset patients (EDI = −6) and more deprived relapsing-onset patients (EDI = 12) was 16.6% (95% confidence interval (CI) [10.3%–22.9%]) for men and 12.3% (95%CI [7.6%–17.0%]) for women. No clear socio-economic mortality gradient was found in progressive-onset patients.

Interpretation

Socio-economic status was associated with mortality due to multiple sclerosis in relapsing-onset patients. Improvements in overall care of more socio-economically deprived patients with multiple sclerosis could help reduce these socio-economic inequalities in multiple sclerosis-related mortality.

Funding

This study was funded by the ARSEP foundation “Fondation pour l'aide à la recherche sur la Sclérose en Plaques” (Grant Reference Number 1122). Data collection has been supported by a grant provided by the French State and handled by the “Agence Nationale de la Recherche,” within the framework of the “Investments for the Future” programme, under the reference ANR-10-COHO-002, Observatoire Français de la Sclérose en Plaques (OFSEP).

Are deprivation-specific cancer survival patterns similar according to individual-based and area-based measures? A cohort study of patients diagnosed with five malignancies in England and Wales, 2008-2016

OBJECTIVE

To investigate if measured inequalities in cancer survival differ when using individual-based ('person') compared with area-based ('place') measures of deprivation for three socioeconomic dimensions: income, deprivation and occupation.

DESIGN

Cohort study.

SETTING

Data from the Office for National Statistics Longitudinal Study of England and Wales, UK, linked to the National Cancer Registration Database.

PARTICIPANTS

Patients diagnosed with cancers of the colorectum, breast, prostate, bladder or with non-Hodgkin's lymphoma during the period 2008-2016.

PRIMARY AND SECONDARY OUTCOME MEASURES

Differentials in net survival between groups defined by individual wage, occupation and education compared with those obtained from corresponding area-level metrics using the English and Welsh Indices of Multiple Deprivation.

RESULTS

Survival was negatively associated with area-based deprivation irrespective of the type analysed, although a trend from least to most deprived was not always observed. Socioeconomic differences were present according to individually-measured socioeconomic groups although there was an absence of a consistent 'gradient' in survival. The magnitude of differentials was similar for area-based and individually-derived measures of deprivation, which was unexpected.

CONCLUSION

These unique data suggest that the socioeconomic influence of 'person' is different to that of 'place' with respect to cancer outcomes. This has implications for health policy aimed at reducing inequalities. Further research could consider the separate and additional influence of area-based deprivation over individual-level characteristics (contextual effects) as well as investigate the geographic, socioeconomic and healthcare-related characteristics of areas with poor outcomes in order to inform policy intervention.

Relationship between socioeconomic status and prostate cancer (incidence, aggressiveness, treatment with curative intent, and mortality): a spatial analysis using population-based cancer registry data

BACKGROUND

Morbidity and mortality associated with prostate cancer in a given geographic area might be related to the level of socioeconomic deprivation. The Somme area (a region of northern France) is considered economically disadvantaged, with major territorial disparities. The aim of this study was to assess the impact of the socioeconomic level on prostate cancer, using data from a population-based cancer registry.

METHODS

The source of data on cases of prostate cancer between 2006 and 2010 was the Somme cancer registry (Amiens, France). Socioeconomic status was measured according to the European Deprivation Index (EDI), which was used to classify each geographical "IRIS" unit (the smallest sub-municipal geographical entity for which French census data are available) according to its level of social deprivation. For spatial analysis, we considered a hierarchical generalized linear model.

RESULTS

In the spatial analysis, prostate cancer incidence was higher in the less disadvantaged areas and treatment frequency with curative intent was lower in the most disadvantaged areas. Cancer aggressiveness and mortality were higher in the most disadvantaged areas: relative risk (RR) = 1.36; 95% CI: [1.09; 1.73] and RR=3.09 [1.70; 5.59], respectively.

CONCLUSION

Our results evidenced a significant association between socioeconomic deprivation and prostate cancer, with worse outcomes among men with the lowest socioeconomic status.

Exploring socioeconomic differences in surgery and in time to elective surgery for colon cancer in England: Population-based study

BACKGROUND

A persistent socioeconomic gap in colon cancer survival is observed in England. Provision of cancer care may also vary by socioeconomic status (SES). We investigated population-based data to explore differential surgical care by SES.

METHODS

We analysed a retrospective cohort of patients diagnosed with colon cancer in England (2010-2013). We examined patterns of presentation and surgery by SES, and whether socioeconomic differences exist in the length of time from diagnosis to elective major resection using linear regression.

RESULTS

Among a total of 68 169 patients with colon cancer, 21.0 % (3138/14 917) in the most affluent group had emergency presentation (EP) whereas 27.9 % (2901/10 386) in the most deprived. Among 45 332 (66.5 %) patients who underwent resection, the proportion of patients receiving urgent surgery (surgery before or ≤ 7 days of diagnosis) was higher in the most deprived group (39.9 %, 2685/6733) than the most affluent (35.4 %, 3595/10 146). Days from diagnosis to elective surgery (surgery > 7 days after diagnosis) ranged from 33.9 (95 % CI 33.1-34.8) in stage II to 38.2 (95 % CI 36.8-39.7) in stage I, but no socioeconomic differences in time were seen in all stages.

CONCLUSIONS

Time to elective surgery for colon cancer did not differ by SES, whereas a higher proportion among deprived patients tended to be diagnosed through EP and to receive urgent surgery. These results suggest that the waiting time target may not be an appropriate measure to assess access to cancer care. Reducing both EP and urgent surgery should be a key policy target.

Small-area analysis on socioeconomic inequalities in cancer survival for 25 cancer sites in Germany

Socioeconomic inequalities in cancer survival have been reported in various countries but it is uncertain to what extent they persist in countries with relatively comprehensive health insurance coverage such as Germany. We investigated the association between area-based socioeconomic deprivation on municipality level and cancer survival for 25 cancer sites in Germany. We used data from seven population-based cancer registries (covering 32 million inhabitants). Patients diagnosed in 1998 to 2014 with one of 25 most common cancer sites were included. Area-based socioeconomic deprivation was assessed using the categorized German Index of Multiple Deprivation (GIMD) on municipality level. We estimated 3-month, 1-year, 5-year and 5-year conditional on 1-year age-standardized relative survival using period approach for 2012 to 2014. Trend analyses were conducted for periods between 2003-2005 and 2012-2014. Model-based period analysis was used to calculate relative excess risks (RER) adjusted for age and stage. In total, 2 333 547 cases were included. For all cancers combined, 5-year survival rates by GIMD quintile were 61.6% in Q1 (least deprived), 61.2% in Q2, 60.4% in Q3, 59.9% in Q4 and 59.0% in Q5 (most deprived). For most cancer sites, the most deprived quintile had lower 5-year survival compared to the least deprived quintile even after adjusting for stage (all cancer sites combined, RER 1.16, 95% confidence interval 1.14-1.19). For some cancer sites, this association was stronger during short-term follow-up. Trend analyses showed improved survival from earlier to recent periods but persisting deprivation differences. The underlying reasons for these persisting survival inequalities and strategies to overcome them should be further investigated.

Water and Soil Pollution: Ecological Environmental Study Methodologies Useful for Public Health Projects. A Literature Review

Health risks at population level may be investigated with different types of environmental studies depending on access to data and funds. Options include ecological studies, case-control studies with individual interviews and human sample analysis, risk assessment or cohort studies. Most public health projects use data and methodologies already available due to the cost of ad-hoc data collection. The aim of the article is to perform a literature review of environmental exposure and health outcomes with main focus on methodologies for assessing an association between water and/or soil pollutants and cancer. A systematic literature search was performed in May 2019 using PubMed. Articles were assessed by four independent reviewers. Forty articles were identified and divided into four groups, according to the data and methods they used, i.e.: (1) regression models with data by geographical area; (2) regression models with data at individual level; (3) exposure intensity threshold values for evaluating health outcome trends; (4) analyses of distance between source of pollutant and health outcome clusters. The issue of exposure assessment has been investigated for over 40 years and the most important innovations regard technologies developed to measure pollutants, statistical methodologies to assess exposure, and software development. Thanks to these changes, it has been possible to develop and apply geo-coding and statistical methods to reduce the ecological bias when considering the relationship between humans, geographic areas, pollutants, and health outcomes. The results of the present review may contribute to optimize the use of public health resources.

Educational inequalities and regional variation in colorectal cancer survival in Finland

BACKGROUND

Previous studies have reported lower colorectal cancer (CRC) survival in patients with low compared to high educational levels. We investigated the impact of education on CRC survival by using both individual and area-based information on education.

METHODS

Patients diagnosed with CRC in Finland in 2007-2016 were followed up for death until the end of 2016. Age-standardized relative survival and relative excess risk of death (RER) were estimated by sex using period approach. RERs were adjusted for age, stage at diagnosis, cancer site, urbanity, hospital district and municipality by using Bayesian piecewise constant excess hazard models. Analyses were conducted including individual (basic, secondary, high) and area-based (quartiles Q1-Q4 based on the proportion of population with basic education) education separately as well as both measures in one model.

RESULTS

We analysed in all 24 462 CRC patients. There was a clear gradient in 5-year relative survival across education groups (men: basic 62 %, secondary 64 %, high 69 %; women: basic 61 %, secondary 67 %, high 71 %). Compared to the basic education group, RER in the high education group was significantly lower. This association was still present after including area-based education in the models (men: RER 0.72, 95 % Confidence interval (CI) 0.64-0.81; women: RER 0.76, 95 % CI 0.59-0.96). Area-based education revealed smaller effect estimates than individual education in CRC survival and no association for men.

CONCLUSION

Individual education information should be preferred over area-based when survival differences are studied by education. Educational differences in CRC survival are still present in Finland.

Regional indices of socio-economic and health inequalities: a tool for public health programming

OBJECTIVES

The aim was to provide an affordable method of computing socio-economic (SE) deprivation indices at the regional level, in order to reveal the specific aspects of the relationship between SE inequalities and health outcomes. The Umbria Region Socio-Health Index (USHI) was computed and compared with the Italian National Deprivation Index at the Umbria regional level (NDI-U).

METHODS

The USHI was computed by applying factor analysis to census tract SE variables correlated with general mortality and validated through comparison with the NDI-U.

RESULTS

Overall mortality presented linear positive trends in USHI, while trends in NDI-U proved non-linear or non-significant. Similar results were obtained with regard to specific causes of death according to deprivation groups, gender and age.

CONCLUSIONS

The USHI better describes a local population in terms of health-related SE status. Policy-makers could therefore adopt this method in order to obtain a better picture of SE-associated health conditions in regional populations and to target strategies for reducing health inequalities.

Colorectal cancer incidence among young adults in England: Trends by anatomical sub-site and deprivation

BACKGROUND

Colorectal cancer incidence in the UK and other high-income countries has been increasing rapidly among young adults. This is the first analysis of colorectal cancer incidence trends by sub-site and socioeconomic deprivation in young adults in a European country.

METHODS

We examined age-specific national trends in colorectal cancer incidence among all adults (20-99 years) diagnosed during 1971-2014, using Joinpoint regression to analyse data from the population-based cancer registry for England. We fitted a generalised linear model to the incidence rates, with a maximum of two knots. We present the annual percentage change in incidence rates in up to three successive calendar periods, by sex, age, deprivation and anatomical sub-site.

RESULTS

Annual incidence rates among the youngest adults (20-39 years) fell slightly between 1971 and the early 1990s, but increased rapidly from then onwards. Incidence Rates (IR) among adults 20-29 years rose from 0.8 per 100,000 in 1993 to 2.8 per 100,000 in 2014, an average annual increase of 8%. An annual increase of 8.1% was observed for adults aged 30-39 years during 2005-2014. Among the two youngest age groups (20-39 years), the average annual increase for the right colon was 5.2% between 1991 and 2010, rising to 19.4% per year between 2010 (IR = 1.2) and 2014 (IR = 2.5). The large increase in incidence rates for cancers of the right colon since 2010 were more marked among the most affluent young adults. Smaller but substantial increases were observed for cancers of the left colon and rectum. Incidence rates in those aged 50 years and older remained stable or decreased over the same periods.

CONCLUSIONS

Despite the overall stabilising trend of colorectal cancer incidence in England, incidence rates have increased rapidly among young adults (aged 20-39 years). Changes in the prevalence of obesity and other risk factors may have affected the young population but more research is needed on the cause of the observed birth cohort effect. Extension of mass screening may not be justifiable due to the low number of newly diagnosed cases but clinicians should be alert to this trend.

Social deprivation indexes and anti-influenza vaccination coverage in the elderly in Sardinia, Italy, with a focus on the Sassari municipality

The aim of the present study was to evaluate the relationship between social deprivation indexes and anti-influenza vaccination coverage in the elderly population (over 65 years old) in Sardinia.

This relationship was first observed in a regional context. An already-known deprivation index was used, and its trivial relationship with anti-influenza vaccination coverage was evaluated. Secondly, the same relationship was assessed in the homogeneous area of the Municipality of Sassari. This required the adoption of an ad hoc deprivation index, which allowed us to stratify the population into deprivation groups and to correlate vaccination coverage with socio-economic variables.

The results showed that regional anti-influenza vaccination coverage increased linearly as deprivation decreased. This trend was confirmed in the Municipality of Sassari. Pearson’s analysis highlighted factors that significantly correlate with vaccination coverage.

In Sardinia, the relationship between anti-influenza vaccination coverage and socio-economic status is consistent with the international panorama, and highlights the necessity to implement interventions to promote vaccination coverage among the elderly.

Summarizing and communicating on survival data according to the audience: a tutorial on different measures illustrated with population-based cancer registry data

Survival data analysis results are usually communicated through the overall survival probability. Alternative measures provide additional insights and may help in communicating the results to a wider audience. We describe these alternative measures in two data settings, the overall survival setting and the relative survival setting, the latter corresponding to the particular competing risk setting in which the cause of death is unavailable or unreliable. In the overall survival setting, we describe the overall survival probability, the conditional survival probability and the restricted mean survival time (restricted to a prespecified time window). In the relative survival setting, we describe the net survival probability, the conditional net survival probability, the restricted mean net survival time, the crude probability of death due to each cause and the number of life years lost due to each cause over a prespecified time window. These measures describe survival data either on a probability scale or on a timescale. The clinical or population health purpose of each measure is detailed, and their advantages and drawbacks are discussed. We then illustrate their use analyzing England population-based registry data of men 15-80 years old diagnosed with colon cancer in 2001-2003, aiming to describe the deprivation disparities in survival. We believe that both the provision of a detailed example of the interpretation of each measure and the software implementation will help in generalizing their use.

Assessment of dietary patterns, physical activity and obesity from a national survey: Rural-urban health disparities in older adults

BACKGROUND

Obesity is a critical public health issue, affecting over one-third of all Americans, and is an underlying cause of numerous health issues across the lifespan. For older adults, obesity is linked to premature declines in physical and mental health and cognitive functioning. The occurrence of obesity and related health behaviors and chronic diseases are higher in rural areas than in urban areas. Furthermore, rural areas of the United States have a higher proportion of older adults than urban areas. Few studies, to date, have explored rural-urban differences in the relationships between dietary patterns and obesity among older adults. Therefore, the purpose of this study is to assess rural-urban differences in obesity rates in older adults, and the potential for the associations between obesity and physical activity and dietary patterns to vary by rural-urban status.

METHODS

Data were abstracted from respondents aged 65 and above from the 2012 Behavioral Risk Factor Surveillance System (BRFSS) database linked to Census-based county-level information on rural-urban status and socioeconomic status. Generalized linear models were utilized to assess rural-urban disparities in obesity, and the potential for associations between obesity and known risk factors (fruit consumption, green vegetable consumption and physical activity) to vary by rural-urban status, accounting for complex sampling and confounders.

RESULTS

Obesity rates were highest and fruit consumption was lowest in the most rural areas. However, for older adults in the most urban areas, there was a significant negative association between obesity and fruit and green vegetable consumption. This association was not observed in more rural older adults.

CONCLUSION

These findings underscore the need to take into account place-based factors such as rural-urban status, when designing and implementing policies and interventions designed to reduce obesity through risk factor mitigation in older adults. To reduce rural-urban disparities in older adults, all policies, programs, and interventions should address the unique barriers and needs specific to rural and urban older adults.

The local Socio-Economic Health Deprivation Index: methods and results

INTRODUCTION

A socio-economic (SE) deprivation index is a measure that aims to provide an indication of SE hardship and disadvantage in the population. Our aim was constructing 10 Socio-Economonic and Health Deprivation Indexes (SEHDI) by means of the same method. This particular method enables these indexes to be used to investigate the relationships between SE inequalities and aspects of health and prevention in the population.

MATERIALS AND METHODS

Data on the demographic and SE situation of the populations were taken from the 2011 Census at the Census Tract (CT) level (2001 for Rome municipality). To construct the SEHDIs, variables displaying a statistically significant correlation with the SMRs of overall mortality were subjected to a tolerance test of linearity, in order to eliminate collinear variables. The variables selected underwent PCA factor analysis, in order to obtain the factors to be linearly combined into the SEHDI. The final values were scaled from minimum to maximum deprivation, and the quantitative scale was converted into five ordinal normalized population groups. The SEHDIs were validated at the SE level by comparing them with the trends of the main SE indexes used in the 2011 Census (2001 for Rome municipality), and at the health level by comparing them with the trends of some causes of death. Both comparisons were made by means of ANOVA.

RESULTS

The 10 areas considered were: the municipalities of Cagliari, Ferrara, Florence, Foggia, Genoa, Rome, Palermo, Sassari, Siena, and the ULSS 7 Veneto area. For each one, a specific SEHDI was computed and the different variables comprising each index focused on particular aspects of SE and health deprivation at the area level. The SEHDIs showed good percentages of explained variance (from 72.2% to 49.1%) and a linear distribution of the main statistical SE indices and of overall mortality in each area; these findings were in line with the literature on the relationship between the SE condition and health status of the population. The distribution of cause-specific mortality across the SEHDIs deprivation clusters is analyzed in other articles, which deal with the findings of the study in each area.

CONCLUSIONS

The SEHDIs showed good ability to identify the elements of SE inequalities that impact on the health conditions of populations; to depict the distribution of causes of death that are sensitive to SE differences concerning aspects of the social and family support structure. From a public health perspective, these results are relevant because they enable interventions of health promotion and prevention to be implemented on the basis of the characteristics that define deprivation groups.

Socioeconomic Differences and Lung Cancer Survival-Systematic Review and Meta-Analysis

Background: The impact of socioeconomic differences on cancer survival has been investigated for several cancer types showing lower cancer survival in patients from lower socioeconomic groups. However, little is known about the relation between the strength of association and the level of adjustment and level of aggregation of the socioeconomic status measure. Here, we conduct the first systematic review and meta-analysis on the association of individual and area-based measures of socioeconomic status with lung cancer survival.

Methods: In accordance with PRISMA guidelines, we searched for studies on socioeconomic differences in lung cancer survival in four electronic databases. A study was included if it reported a measure of survival in relation to education, income, occupation, or composite measures (indices). If possible, meta-analyses were conducted for studies reporting on individual and area-based socioeconomic measures.

Results: We included 94 studies in the review, of which 23 measured socioeconomic status on an individual level and 71 on an area-based level. Seventeen studies were eligible to be included in the meta-analyses. The meta-analyses revealed a poorer prognosis for patients with low individual income (pooled hazard ratio: 1.13, 95 % confidence interval: 1.08–1.19, reference: high income), but not for individual education. Group comparisons for hazard ratios of area-based studies indicated a poorer prognosis for lower socioeconomic groups, irrespective of the socioeconomic measure. In most studies, reported 1-, 3-, and 5-year survival rates across socioeconomic status groups showed decreasing rates with decreasing socioeconomic status for both individual and area-based measures. We cannot confirm a consistent relationship between level of aggregation and effect size, however, comparability across studies was hampered by heterogeneous reporting of socioeconomic status and survival measures. Only eight studies considered smoking status in the analysis.

Conclusions: Our findings suggest a weak positive association between individual income and lung cancer survival. Studies reporting on socioeconomic differences in lung cancer survival should consider including smoking status of the patients in their analysis and to stratify by relevant prognostic factors to further explore the reasons for socioeconomic differences. A common definition for socioeconomic status measures is desirable to further enhance comparisons between nations and across different levels of aggregation.

Describing the association between socioeconomic inequalities and cancer survival: methodological guidelines and illustration with population-based data

BACKGROUND

Describing the relationship between socioeconomic inequalities and cancer survival is important but methodologically challenging. We propose guidelines for addressing these challenges and illustrate their implementation on French population-based data.

METHODS

We analyzed 17 cancers. Socioeconomic deprivation was measured by an ecological measure, the European Deprivation Index (EDI). The Excess Mortality Hazard (EMH), ie, the mortality hazard among cancer patients after accounting for other causes of death, was modeled using a flexible parametric model, allowing for nonlinear and/or time-dependent association between the EDI and the EMH. The model included a cluster-specific random effect to deal with the hierarchical structure of the data.

RESULTS

We reported the conventional age-standardized net survival (ASNS) and described the changes of the EMH over the time since diagnosis at different levels of deprivation. We illustrated nonlinear and/or time-dependent associations between the EDI and the EMH by plotting the excess hazard ratio according to EDI values at different times after diagnosis. The median excess hazard ratio quantified the general contextual effect. Lip-oral cavity-pharynx cancer in men showed the widest deprivation gap, with 5-year ASNS at 41% and 29% for deprivation quintiles 1 and 5, respectively, and we found a nonlinear association between the EDI and the EMH. The EDI accounted for a substantial part of the general contextual effect on the EMH. The association between the EDI and the EMH was time dependent in stomach and pancreas cancers in men and in cervix cancer.

CONCLUSION

The methodological guidelines proved efficient in describing the way socioeconomic inequalities influence cancer survival. Their use would allow comparisons between different health care systems.

Socio-economic inequalities in the incidence of four common cancers: a population-based registry study

Objectives

To investigate the relationship between socio-economic circumstances and cancer incidence in Scotland in recent years.

Study design

Population-based study using cancer registry data.

Methods

Data on incident cases of colorectal, lung, female breast, and prostate cancer diagnosed between 2001 and 2012 were obtained from a population-based cancer registry covering a population of approximately 2.5 million people in the West of Scotland. Socio-economic circumstances were assessed based on postcode of residence at diagnosis, using the Scottish Index of Multiple Deprivation (SIMD). For each cancer, crude and age-standardised incidence rates were calculated by quintile of SIMD score, and the number of excess cases associated with socio-economic deprivation was estimated.

Results

93,866 cases met inclusion criteria, comprising 21,114 colorectal, 31,761 lung, 23,757 female breast, and 15,314 prostate cancers. Between 2001 and 2006, there was no consistent association between socio-economic circumstances and colorectal cancer incidence, but 2006–2012 saw an emerging deprivation gradient in both sexes. The incidence rate ratio (IRR) for colorectal cancer between most deprived and least deprived increased from 1.03 (95% confidence interval [CI] 0.91–1.16) to 1.24 (95% CI 1.11–1.39) during the study period. The incidence of lung cancer showed the strongest relationship with socio-economic circumstances, with inequalities widening across the study period among women from IRR 2.66 (95% CI 2.33–3.05) to 2.91 (95% CI 2.54–3.33) in 2001–03 and 2010–12, respectively. Breast and prostate cancer showed an inverse relationship with socio-economic circumstances, with lower incidence among people living in more deprived areas.

Conclusion

Significant socio-economic inequalities remain in cancer incidence in the West of Scotland, and in some cases are increasing. In particular, this study has identified an emerging, previously unreported, socio-economic gradient in colorectal cancer incidence among women as well as men. Actions to prevent, mitigate, and undo health inequalities should be a public health priority.

•

There is an emerging social gradient in colorectal cancer incidence in both sexes.

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Profound socio-economic inequalities in lung cancer persist.

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Breast and prostate cancer remain more common among less deprived populations.

Understanding the effects of socioeconomic status along the breast cancer continuum in Australian women: a systematic review of evidence

Background

Globally, the provision of equitable outcomes for women with breast cancer is a priority for governments. However, there is growing evidence that a socioeconomic status (SES) gradient exists in outcomes across the breast cancer continuum – namely incidence, diagnosis, treatment, survival and mortality. This systematic review describes this evidence and, because of the importance of place in defining SES, findings are limited to the Australian experience.

Methods

An on-line search of PubMed and the Web of Science identified 44 studies published since 1995 which examined the influence of SES along the continuum. The critique of studies included the study design, the types and scales of SES variable measured, and the results in terms of direction and significance of the relationships found. To aid in the interpretation of results, the findings were discussed in the context of a systems dynamic feedback diagram.

Results

We found 67 findings which reported 107 relationships between SES within outcomes along the continuum. Results suggest no differences in the participation in screening by SES. Higher incidence was reported in women with higher SES whereas a negative association was reported between SES and diagnosis. Associations with treatment choice were specific to the treatment choice undertaken. Some evidence was found towards greater survival for women with higher SES, however, the evidence for a SES relationship with mortality was less conclusive.

Conclusions

In a universal health system such as that in Australia, evidence of an SES gradient exists, however, the strength and direction of this relationship varies along the continuum. This is a complex relationship and the heterogeneity in study design, the SES indicator selected and its representative scale further complicates our understanding of its influence. More complex multilevel studies are needed to better understand these relationships, the interactions between predictors and to reduce biases introduced by methodological issues.

Patient navigation to reduce social inequalities in colorectal cancer screening participation: A cluster randomized controlled trial

Despite free colorectal cancer screening in France, participation remains low and low socioeconomic status is associated with a low participation. Our aim was to assess the effect of a screening navigation program on participation and the reduction in social inequalities in a national-level organized mass screening program for colorectal cancer by fecal-occult blood test (FOBT). A multicenter (3 French departments) cluster randomized controlled trial was conducted over two years. The cluster was a small geographical unit stratified according to a deprivation index and the place of residence. A total of 14,556 subjects (72 clusters) were included in the control arm where the FOBT program involved the usual postal reminders, and 14,373 subjects (66 clusters) were included in the intervention arm. Intervention concerned only non-attended subjects with a phone number available defined as the navigable population. A screening navigator was added to the usual screening organization to identify and eliminate barriers to CRC screening with personalized contact. The participation rate by strata increased in the intervention arm. The increase was greater in affluent strata than in deprived ones. Multivariate analyses demonstrated that the intervention mainly with phone navigation increased individual participation (OR=1.19 [1.10, 1.29]) in the navigable population. For such interventions to reduce social inequalities in a country with a national level organized mass screening program, they should first be administered to deprived populations, in accordance with the principle of proportionate universalism. ClinicalTrials.gov Identifier: NCT01555450.

Cancer survival disparities worsening by socio-economic disadvantage over the last 3 decades in new South Wales, Australia

BACKGROUND

Public concerns are commonly expressed about widening health gaps. This cohort study examines variations and trends in cancer survival by socio-economic disadvantage, geographical remoteness and country of birth in an Australian population over a 30-year period.

METHODS

Data for cases diagnosed in New South Wales (NSW) in 1980-2008 (n = 651,245) were extracted from the population-based NSW Cancer Registry. Competing risk regression models, using the Fine & Gray method, were used for comparative analyses to estimate sub-hazard ratios (SHR) with 95% confidence intervals (CI) among people diagnosed with cancer.

RESULTS

Increased risk of cancer death was associated with living in the most socio-economically disadvantaged areas compared with the least disadvantaged areas (SHR 1.15, 95% CI 1.13-1.17), and in outer regional/remote areas compared with major cities (SHR 1.05, 95% CI 1.03-1.06). People born outside Australia had a similar or lower risk of cancer death than Australian-born (SHR 0.99, 95% CI 0.98-1.01 and SHR 0.91, 95% CI 0.90-0.92 for people born in other English and non-English speaking countries, respectively). An increasing comparative risk of cancer death was observed over time when comparing the most with the least socio-economically disadvantaged areas (SHR 1.07, 95% CI 1.04-1.10 for 1980-1989; SHR 1.14, 95% CI 1.12-1.17 for 1990-1999; and SHR 1.24, 95% CI 1.21-1.27 for 2000-2008; p < 0.001 for interaction between disadvantage quintile and year of diagnosis).

CONCLUSIONS

There is a widening gap in comparative risk of cancer death by level of socio-economic disadvantage that warrants a policy response and further examination of reasons behind these disparities.

Is there a socioeconomic variation in survival from renal tumours in children and young people resident in northern England (1968-2012)?

BACKGROUND

Despite strong evidence of a social gradient in cancer survival among UK adults, studies in children and young people remain inconclusive and have not included renal tumours. This study investigated the relationship between socioeconomic status and survival from renal tumours among children and young people.

PROCEDURE

Kaplan-Meier estimation and Cox regression were used to analyse survival for all 209 renal tumours in children and young people (0-24 years) diagnosed 1968-2012 and registered by a specialist population-based registry. Sociodemographic and clinicopathologic variables, including paternal occupation at birth, were also analysed.

RESULTS

No significant disparity in overall renal tumour and Wilms tumour (WT) survival was observed according to paternal social class [p=0.988 and 0.808, respectively]. The strongest predictor of survival was stage, with late stage (III-IV) disease having a 4-fold higher risk of death compared to early stage (I-II) disease [p<0.001]. Similarly, high mortality-risk was seen for late stage WT in children aged 0-14 years (Hazard Ratio=6.37; 95% CI=2.60-15.59).

CONCLUSIONS

This study did not detect a significant social gradient in renal tumour survival. The identification of tumour stage as a strong predictor of survival irrespective of age, necessitates the development of appropriate public health interventions that target early diagnosis and treatment.

Does exclusion of cancers registered only from death-certificate information diminish socio-demographic disparities in recorded survival?

BACKGROUND

Death Certificate Only (DCO) cancer cases are commonly excluded from survival analyses due to unknown survival time. This study examines whether socio-demographic factors are associated with DCO diagnosis, and the potential effects of excluding DCO cases on socio-demographic cancer survival disparities in NSW, Australia.

METHODS

NSW Cancer Registry data for cases diagnosed in 2000-2008 were used in this study. Logistic regression was used to estimate the odds of DCO registration by socio-demographic sub-group (socio-economic disadvantage, residential remoteness, country of birth, age at diagnosis). Cox proportional hazard regression was used to estimate the probability of death from cancer by socio-demographic subgroup when DCO cases were included and excluded from analyses.

RESULTS

DCO cases consisted of 1.5% (n=4336) of all cases (n=299,651). DCO diagnosis was associated with living in socio-economically disadvantaged areas (most disadvantaged compared with least disadvantaged quintile: odds ratio OR 1.25, 95%CI 1.12-1.40), living in inner regional (OR 1.16, 95%CI 1.08-1.25) or remote areas (OR 1.48, 95%CI 1.01-2.19), having an unknown country of birth (OR 1.63, 95%CI 1.47-1.81) and older age. Including or excluding DCO cases had no significant impact on hazard ratios for cancer death by socio-economic disadvantage quintile or remoteness category, and only a minor impact on hazard ratios by age.

CONCLUSION

Socio-demographic factors were associated with DCO diagnosis in NSW. However, socio-demographic cancer survival disparities remained unchanged or varied only slightly irrespective of including/excluding DCO cases. Further research could examine the upper limits of DCO proportions that significantly alter estimated cancer survival differentials if DCOs are excluded.

Assessment of the ecological bias of seven aggregate social deprivation indices

Background

In aggregate studies, ecological indices are used to study the influence of socioeconomic status on health. Their main limitation is ecological bias. This study assesses the misclassification of individual socioeconomic status in seven ecological indices.

Methods

Individual socioeconomic data for a random sample of 10,000 persons came from periodic health examinations conducted in 2006 in 11 French departments. Geographical data came from the 2007 census at the lowest geographical level available in France. The Receiver Operating Characteristics (ROC) curves, the areas under the curves (AUC) for each individual variable, and the distribution of deprived and non-deprived persons in quintiles of each aggregate score were analyzed.

Results

The aggregate indices studied are quite good “proxies” for individual deprivation (AUC close to 0.7), and they have similar performance. The indices are more efficient at measuring individual income than education or occupational category and are suitable for measuring of deprivation but not affluence.

Conclusions

The study inventoried the aggregate indices available in France and evaluated their assessment of individual SES.

The impact of geographic unit of analysis on socioeconomic inequalities in cancer survival and distant summary stage - a population-based study

OBJECTIVE

When using area-level disadvantage measures, size of geographic unit can have major effects on recorded socioeconomic cancer disparities. This study examined the extent of changes in recorded socioeconomic inequalities in cancer survival and distant stage when the measure of socioeconomic disadvantage was based on smaller Census Collection Districts (CDs) instead of Statistical Local Areas (SLAs).

METHODS

Population-based New South Wales Cancer Registry data were used to identify cases diagnosed with primary invasive cancer in 2000-2008 (n=264,236). Logistic regression and competing risk regression modelling were performed to examine socioeconomic differences in odds of distant stage and hazard of cancer death for all sites combined and separately for breast, prostate, colorectal and lung cancers.

RESULTS

For all sites collectively, associations between socioeconomic disadvantage and cancer survival and distant stage were stronger when the CD-based socioeconomic disadvantage measure was used compared with the SLA-based measure. The CD-based measure showed a more consistent socioeconomic gradient with a linear upward trend of risk of cancer death/distant stage with increasing socioeconomic disadvantage. Site-specific analyses provided similar findings for the risk of death but less consistent results for the likelihood of distant stage.

CONCLUSIONS

The use of socioeconomic disadvantage measure based on the smallest available spatial unit should be encouraged in the future. Implications for public health: Disadvantage measures based on small spatial units can more accurately identify socioeconomic cancer disparities to inform priority settings in service planning.

Factors related to the relative survival of patients with diffuse large B-cell lymphoma in a population-based study in France: does socio-economic status have a role?

The survival of patients with diffuse large B-cell lymphoma has increased during the last decade as a result of addition of anti-CD20 to anthracycline-based chemotherapy. Although the trend is encouraging, there are persistent differences in survival within and between the USA and European countries suggesting that non-biological factors play a role. Our aim was to investigate the influence of such factors on relative survival of patients with diffuse large B-cell lymphoma. We conducted a retrospective, multicenter, registry-based study in France on 1165 incident cases of diffuse large B-cell lymphoma between 2002 and 2008. Relative survival analyses were performed and missing data were controlled with the multiple imputation method. In a multivariate analysis, adjusted for age, sex and International Prognostic Index, we confirmed that time period was associated with a better 5-year relative survival. The registry area, the medical specialty of the care department (onco-hematology versus other), the time to travel to the nearest teaching hospital, the place of treatment (teaching versus not-teaching hospital -borderline significance), a comorbidity burden and marital status were independently associated with the 5-year relative survival. Adjusted for first-course treatment, inclusion in a clinical trial and treatment discussion in a multidisciplinary meeting were strongly associated with a better survival outcome. In contrast, socio-economic status (determined using the European Deprivation Index) was not associated with outcome. Despite therapeutic advances, various non-biological factors affected the relative survival of patients with diffuse large B-cell lymphoma. The notion of lymphoma-specific expertise seems to be essential to achieve optimal care management and reopens the debate regarding centralization of these patients’ care in hematology/oncology departments.

No inequalities in survival from colorectal cancer by education and socioeconomic deprivation - a population-based study in the North Region of Portugal, 2000-2002

BACKGROUND

Association between cancer survival and socioeconomic status has been reported in various countries but it has never been studied in Portugal. We aimed here to study the role of education and socioeconomic deprivation level on survival from colorectal cancer in the North Region of Portugal using a population-based cancer registry dataset.

METHODS

We analysed a cohort of patients aged 15-84 years, diagnosed with a colorectal cancer in the North Region of Portugal between 2000 and 2002. Education and socioeconomic deprivation level was assigned to each patient based on their area of residence. We measured socioeconomic deprivation using the recently developed European Deprivation Index. Net survival was estimated using Pohar-Perme estimator and age-adjusted excess hazard ratios were estimated using parametric flexible models. Since no deprivation-specific life tables were available, we performed a sensitivity analysis to test the robustness of the results to life tables adjusted for education and socioeconomic deprivation level.

RESULTS

A total of 4,105 cases were included in the analysis. In male patients (56.3 %), a pattern of worse 5- and 10-year net survival in the less educated (survival gap between extreme education groups: -7 % and -10 % at 5 and 10 years, respectively) and more deprived groups (survival gap between extreme EDI groups: -5 % both at 5 and 10 years) was observed when using general life tables. No such clear pattern was found among female patients. In both sexes, when likely differences in background mortality by education or deprivation were accounted for in the sensitivity analysis, any differences in net survival between education or deprivation groups vanished.

CONCLUSIONS

Our study shows that observed differences in survival by education and EDI level are most likely attributable to inequalities in background survival. Also, it confirms the importance of using the relevant life tables and of performing sensitivity analysis when evaluating socioeconomic inequalities in cancer survival. Comparison studies of different healthcare systems organization should be performed to better understand its influence on cancer survival inequalities.

Impact of geographic area level on measuring socioeconomic disparities in cancer survival in New South Wales, Australia: A period analysis

BACKGROUND

Area-based socioeconomic measures are widely used in health research. In theory, the larger the area used the more individual misclassification is introduced, thus biasing the association between such area level measures and health outcomes. In this study, we examined the socioeconomic disparities in cancer survival using two geographic area-based measures to see if the size of the area matters.

METHODS

We used population-based cancer registry data for patients diagnosed with one of 10 major cancers in New South Wales (NSW), Australia during 2004-2008. Patients were assigned index measures of socioeconomic status (SES) based on two area-level units, census Collection District (CD) and Local Government Area (LGA) of their address at diagnosis. Five-year relative survival was estimated using the period approach for patients alive during 2004-2008, for each socioeconomic quintile at each area-level for each cancer. Poisson-regression modelling was used to adjust for socioeconomic quintile, sex, age-group at diagnosis and disease stage at diagnosis. The relative excess risk of death (RER) by socioeconomic quintile derived from this modelling was compared between area-units.

RESULTS

We found extensive disagreement in SES classification between CD and LGA levels across all socioeconomic quintiles, particularly for more disadvantaged groups. In general, more disadvantaged patients had significantly lower survival than the least disadvantaged group for both CD and LGA classifications. The socioeconomic survival disparities detected by CD classification were larger than those detected by LGA. Adjusted RER estimates by SES were similar for most cancers when measured at both area levels.

CONCLUSIONS

We found that classifying patient SES by the widely used Australian geographic unit LGA results in underestimation of survival disparities for several cancers compared to when SES is classified at the geographically smaller CD level. Despite this, our RER of death estimates derived from these survival estimates were generally similar for both CD and LGA level analyses, suggesting that LGAs remain a valuable spatial unit for use in Australian health and social research, though the potential for misclassification must be considered when interpreting research. While data confidentiality concerns increase with the level of geographical precision, the use of smaller area-level health and census data in the future, with appropriate allowance for confidentiality.

Impact of deprivation on breast cancer survival among women eligible for mammographic screening in the West Midlands (UK) and New South Wales (Australia): Women diagnosed 1997-2006

Women diagnosed with breast cancer in the UK display marked differences in survival between categories defined by socio-economic deprivation. Timeliness of diagnosis is one of the possible explanations for these patterns. Women whose cancer is screen-detected are more likely to be diagnosed at an earlier stage. We examined deprivation and screening-specific survival in order to evaluate the role of early diagnosis upon deprivation-specific survival differences in the West Midlands (UK) and New South Wales (Australia). We estimated net survival for women aged 50-65 years at diagnosis and whom had been continuously eligible for screening from the age of 50. Records for 5,628 women in West Midlands (98.5% of those eligible, mean age at diagnosis 53.7 years) and 6,396 women in New South Wales (99.9% of those eligible, mean age at diagnosis 53.8 years). In New South Wales, survival was similar amongst affluent and deprived women, regardless of whether their cancer was screen-detected or not. In the West Midlands, there were large and persistent differences in survival between affluent and deprived women. Deprivation differences were similar between the screen-detected and non-screen detected groups. These differences are unlikely to be solely explained by artefact, or by patient or tumour factors. Further investigations into the timeliness and appropriateness of the treatments received by women with breast cancer across the social spectrum in the UK are warranted.

Development of a cross-cultural deprivation index in five European countries

BACKGROUND

Despite a concerted policy effort in Europe, social inequalities in health are a persistent problem. Developing a standardised measure of socioeconomic level across Europe will improve the understanding of the underlying mechanisms and causes of inequalities. This will facilitate developing, implementing and assessing new and more effective policies, and will improve the comparability and reproducibility of health inequality studies among countries. This paper presents the extension of the European Deprivation Index (EDI), a standardised measure first developed in France, to four other European countries-Italy, Portugal, Spain and England, using available 2001 and 1999 national census data.

METHODS AND RESULTS

The method previously tested and validated to construct the French EDI was used: first, an individual indicator for relative deprivation was constructed, defined by the minimal number of unmet fundamental needs associated with both objective (income) poverty and subjective poverty. Second, variables available at both individual (European survey) and aggregate (census) levels were identified. Third, an ecological deprivation index was constructed by selecting the set of weighted variables from the second step that best correlated with the individual deprivation indicator.

CONCLUSIONS

For each country, the EDI is a weighted combination of aggregated variables from the national census that are most highly correlated with a country-specific individual deprivation indicator. This tool will improve both the historical and international comparability of studies, our understanding of the mechanisms underlying social inequalities in health and implementation of intervention to tackle social inequalities in health.

Socioeconomic disparities in childhood cancer survival in Switzerland

In this study, we investigated whether childhood cancer survival in Switzerland is influenced by socioeconomic status (SES), and if disparities vary by type of cancer and definition of SES (parental education, living condition, area-based SES). Using Cox proportional hazards models, we analyzed 5-year cumulative mortality in all patients registered in the Swiss Childhood Cancer Registry diagnosed 1991-2006 below 16 years. Information on SES was extracted from the Swiss census by probabilistic record linkage. The study included 1602 children (33% with leukemia, 20% with lymphoma, 22% with central nervous system (CNS) tumors); with an overall 5-year survival of 77% (95%CI 75-79%). Higher SES, particularly parents' education, was associated with a lower 5-year cumulative mortality. Results varied by type of cancer with no association for leukemia and particularly strong effects for CNS tumor patients, where mortality hazard ratios for the different SES indicators, comparing the highest with the lowest group, ranged from 0.48 (95%CI: 0.28-0.81) to 0.71 (95%CI: 0.44-1.15). We conclude that even in Switzerland with a high quality health care system and mandatory health insurance, socioeconomic differences in childhood cancer survival persist. Factors causing these survival differences have to be further explored, to facilitate universal access to optimal treatment and finally eliminate social inequalities in childhood cancer survival.

Cancer survival in New South Wales, Australia: socioeconomic disparities remain despite overall improvements

Background

Disparities in cancer survival by socioeconomic status have been reported previously in Australia. We investigated whether those disparities have changed over time.

Methods

We used population-based cancer registry data for 377,493 patients diagnosed with one of 10 major cancers in New South Wales (NSW), Australia. Patients were assigned to an area-based measure of socioeconomic status. Five-year relative survival was estimated for each socioeconomic quintile in each ‘at risk’ period (1996–2000 and 2004–2008) for the 10 individual cancers. Poisson-regression modelling was used to adjust for several prognostic factors. The relative excess risk of death by socioeconomic quintile derived from this modelling was compared over time.

Results

Although survival increased over time for most individual cancers, Poisson-regression models indicated that socioeconomic disparities continued to exist in the recent period. Significant socioeconomic disparities were observed for stomach, colorectal, liver, lung, breast and prostate cancer in 1996–2000 and remained so for 2004–2008, while significant disparities emerged for cervical and uterus cancer in 2004–2008 (although the interaction between period and socioeconomic status was not significant). About 13.4 % of deaths attributable to a diagnosis of cancer could have been postponed if this socioeconomic disparity was eliminated.

Conclusion

While recent health and social policies in NSW have accompanied an increase in cancer survival overall, they have not been associated with a reduction in socioeconomic inequalities.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-016-2065-z) contains supplementary material, which is available to authorized users.

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

Being a highly industrialized country with one of the highest male lung cancer mortality rates in Europe, Belgium is an interesting study area for lung cancer research. This study investigates geographical patterns in lung cancer mortality in Belgium. More specifically it probes into the contribution of individual as well as area-level characteristics to (sub-district patterns in) lung cancer mortality. Data from the 2001 census linked to register data from 2001-2011 are used, selecting all Belgian inhabitants aged 65+ at time of the census. Individual characteristics include education, housing status and home ownership. Urbanicity, unemployment rate, the percentage employed in mining and the percentage employed in other high-risk industries are included as sub-district characteristics. Regional variation in lung cancer mortality at sub-district level is estimated using directly age-standardized mortality rates. The association between lung cancer mortality and individual and area characteristics, and their impact on the variation of sub-district level is estimated using multilevel Poisson models. Significant sub-district variations in lung cancer mortality are observed. Individual characteristics explain a small share of this variation, while a large share is explained by sub-district characteristics. Individuals with a low socioeconomic status experience a higher lung cancer mortality risk. Among women, an association with lung cancer mortality is found for the sub-district characteristics urbanicity and unemployment rate, while for men lung cancer mortality was associated with the percentage employed in mining. Not just individual characteristics, but also area characteristics are thus important determinants of (regional differences in) lung cancer mortality.

40 years of progress in female cancer death risk: a Bayesian spatio-temporal mapping analysis in Switzerland

BACKGROUND

In the past decades, mortality of female gender related cancers declined in Switzerland and other developed countries. Differences in the decrease and in spatial patterns within Switzerland have been reported according to urbanisation and language region, and remain controversial. We aimed to investigate geographical and temporal trends of breast, ovarian, cervical and uterine cancer mortality, assess whether differential trends exist and to provide updated results until 2011.

METHODS

Breast, ovarian, cervical and uterine cancer mortality and population data for Switzerland in the period 1969-2011 was retrieved from the Swiss Federal Statistical office (FSO). Cases were grouped into <55 year olds, 55-74 year olds and 75+ year olds. The geographical unit of analysis was the municipality. To explore age- specific spatio-temporal patterns we fitted Bayesian hierarchical spatio-temporal models on subgroup-specific death rates indirectly standardized by national references. We used linguistic region and degree of urbanisation as covariates.

RESULTS

Female cancer mortality continuously decreased in terms of rates in all age groups and cancer sites except for ovarian cancer in 75+ year olds, especially since 1990 onwards. Contrary to other reports, we found no systematic difference between language regions. Urbanisation as a proxy for access to and quality of medical services, education and health consciousness seemed to have no influence on cancer mortality with the exception of uterine and ovarian cancer in specific age groups. We observed no obvious spatial pattern of mortality common for all cancer sites. Rate reduction in cervical cancer was even stronger than for other cancer sites.

CONCLUSIONS

Female gender related cancer mortality is continuously decreasing in Switzerland since 1990. Geographical differences are small, present on a regional or canton-overspanning level, and different for each cancer site and age group. No general significant association with cantonal or language region borders could be observed.

Socioeconomic inequalities in prostate cancer survival: A review of the evidence and explanatory factors

Although survival rates after prostate cancer diagnosis have improved in the past two decades, survival analyses regarding the socioeconomic status (SES) suggest inequalities indicating worse prognosis for lower SES groups. An overview of the current literature is lacking and moreover, there is an ongoing discussion about the underlying causes but evidence is comparatively sparse. Several patient, disease and health care related factors are discussed to have an important impact on disparities in survival. Therefore, a systematic review was conducted to sum up the current evidence of survival inequalities and the contribution of different potential explanatory factors among prostate cancer patients. The PubMed database was screened for relevant articles published between January 2005 and September 2014 revealing 330 potentially eligible publications. After systematic review process, 46 papers met the inclusion criteria and were included in the review. About 75% of the studies indicate a significant association between low SES and worse survival among prostate cancer patients in the fully adjusted model. Overall, hazard ratios (low versus high SES) range from 1.02 to 3.57. A decrease of inequalities over the years was not identified. 8 studies examined the impact of explanatory factors on the association between SES and survival by progressive adjustment indicating mediating effects of comorbidity, stage at diagnosis and treatment modalities. Eventually, an apparent majority of the obtained studies indicates lower survival among patients with lower SES. The few studies that intend to explain inequalities found out instructive results regarding different contributing factors but evidence is still insufficient.

Health disparities and cancer: racial disparities in cancer mortality in the United States, 2000-2010

Declining cancer incidence and mortality rates in the United States (U.S.) have continued through the first decade of the twenty-first century. Reductions in tobacco use, greater uptake of prevention measures, adoption of early detection methods, and improved treatments have resulted in improved outcomes for both men and women. However, Black Americans continue to have the higher cancer mortality rates and shorter survival times. This review discusses and compares the cancer mortality rates and mortality trends for Blacks and Whites. The complex relationship between socioeconomic status and race and its contribution to racial cancer disparities is discussed. Based on current trends and the potential and limitations of the patient protection and affordable care act with its mandate to reduce health care inequities, future trends, and challenges in cancer mortality disparities in the U.S. are explored.

A novel ecological methodology for constructing ethnic-majority life tables in the absence of individual ethnicity information

BACKGROUND

Deprivation-specific life tables have been in use for some time, but health outcomes are also known to vary by ethnicity over and above deprivation. The mortality experiences of ethnic groups are little studied in the UK, however, because ethnicity is not captured on death certificates.

METHODS

Population data for all Output Areas (OAs) in England and Wales were stratified by age-group, sex and ethnic proportion, and matched to the deaths counts in that OA from 2000 to 2002. We modelled the relationship between mortality, age, deprivation and ethnic proportion. We predicted mortality rates for an area that contained the maximum proportion of each ethnic group reported in any area in England and Wales, using a generalised linear model with a Poisson distribution adjusted for deprivation.

RESULTS

After adjustment, Asian and White life expectancies between 1 and 80 years were very similar. Black men and women had lower life expectancies: men by 4 years and women by around 1.5 years. The Asian population had the lowest mortality of all groups over age 45 in women and over 50 in men, whereas the Black population had the highest rates throughout, except in girls under 15.

CONCLUSIONS

We adopted a novel ecological method of constructing ethnic-majority life tables, adjusted for deprivation. There is still diversity within these three broad ethnic groups, but our data show important residual differences in mortality for Black men and women. These ethnic life tables can be used to inform public health planning and correctly account for background mortality in ethnic subgroups of the population.

A cross-sectional ecological study of spatial scale and geographic inequality in access to drinking-water and sanitation

Introduction

Measuring inequality in access to safe drinking-water and sanitation is proposed as a component of international monitoring following the expiry of the Millennium Development Goals. This study aims to evaluate the utility of census data in measuring geographic inequality in access to drinking-water and sanitation.

Methods

Spatially referenced census data were acquired for Colombia, South Africa, Egypt, and Uganda, whilst non-spatially referenced census data were acquired for Kenya. Four variants of the dissimilarity index were used to estimate geographic inequality in access to both services using large and small area units in each country through a cross-sectional, ecological study.

Results

Inequality was greatest for piped water in South Africa in 2001 (based on 53 areas (N) with a median population (MP) of 657,015; D = 0.5599) and lowest for access to an improved water source in Uganda in2008 (N = 56; MP = 419,399; D = 0.2801). For sanitation, inequality was greatest for those lacking any facility in Kenya in 2009 (N = 158; MP = 216,992; D = 0.6981), and lowest for access to an improved facility in Uganda in 2002 (N = 56; MP = 341,954; D = 0.3403). Although dissimilarity index values were greater for smaller areal units, when study countries were ranked in terms of inequality, these ranks remained unaffected by the choice of large or small areal units. International comparability was limited due to definitional and temporal differences between censuses.

Conclusions

This five-country study suggests that patterns of inequality for broad regional units do often reflect inequality in service access at a more local scale. This implies household surveys designed to estimate province-level service coverage can provide valuable insights into geographic inequality at lower levels. In comparison with household surveys, censuses facilitate inequality assessment at different spatial scales, but pose challenges in harmonising water and sanitation typologies across countries.

Stage at breast cancer diagnosis and distance from diagnostic hospital in a periurban setting: a South African public hospital case series of over 1,000 women

Advanced stage at diagnosis contributes to low breast cancer survival rates in sub-Saharan Africa. Living far from health services is known to delay presentation, but the effect of residential distance to hospital, the radius at which this effect sets in and the women most affected have not been quantified. In a periurban South African setting, we examined the effect of a geographic information system (GIS)-measured straight-line distance, from a patient's residence to diagnostic hospital, on stage at diagnosis in 1,071 public-sector breast cancer patients diagnosed during 2006-2012. Generalized linear models were used to estimate risk ratios for late stage (stage III/IV vs. stage I/II) associated with distance, adjusting for year of diagnosis, age, race and socioeconomic indicators. Mean age of patients was 55 years, 90% were black African and diagnoses were at stages I (5%), II (41%), III (46%) and IV (8%). Sixty-two percent of patients with distances >20 km (n = 338) had a late stage at diagnosis compared to 50% with distances <20 km (n = 713, p = 0.02). Risk of late stage at diagnosis was 1.25-fold higher (95% CI: 1.09, 1.42) per 30 km. Effects were pronounced in an underrepresented group of patients over age 70. This positive stage-distance association held to 40 km, and plateaued or slightly reversed in patients (9%) living beyond this distance. Studies of woman and the societal and healthcare-level influences on these delays and on the late stage at diagnosis distribution are needed to inform interventions to improve diagnostic stage and breast cancer survival in this and similar settings.

Socioeconomic inequalities in cancer survival: a population-based study of adult patients diagnosed in Osaka, Japan, during the period 1993-2004

BACKGROUND

Long-term recession of the Japanese economy during the 1990s led to growing social inequalities whilst health inequalities also appeared. The 2007 National Cancer Control Program of Japan targeted "equalisation of cancer medical services", but the system to monitor health inequalities was still inadequate. We aimed to measure socioeconomic inequalities in cancer survival in Japan.

MATERIAL AND METHODS

We analysed 13 common invasive, primary, malignant tumours diagnosed from 1993 to 2004 and registered by the population-based Cancer Registry of Osaka Prefecture. An ecological socioeconomic deprivation index based on small area statistics, divided into quintile groups, was linked to patients according to their area of residence at the time of diagnosis. We estimated one-, five-year and conditional five-year net survival by sex, period of diagnosis (1993-1996/1997-2000/2001-2004) and deprivation group. Changes in survival over time, deprivation gap in survival, and change in deprivation gap were estimated at one and five years after diagnosis using variance-weighted least square regression.

RESULTS

The deprivation gap in one-year net survival was narrower than in five-year net survival and conditional five-year survival. During the study period, there was no change in deprivation gap, except for reductions for pancreas (men) and stomach (women), and an increase for lung (men) in one-year survival. We observed a linear association between level of survival and deprivation gap at five years and conditional five years, but no association at one-year survival.

CONCLUSION

A wide deprivation gap in survival was observed in most of the adult, solid, malignant tumours, within the universal healthcare system in Japan. Overall, cancer survival improved in Osaka without any widening of inequalities in cancer survival in 1993-2004, shortly after the long-term economic recession and deep modifications in the social and work environments in Japan. The longer term impact of the recession on inequalities in cancer survival needs to be monitored using population-based cancer registry data.

Temporal changes in breast cancer incidence in South Asian women

BACKGROUND

Breast cancer in the UK resident population of South Asian ethnicity has been lower than that in indigenous women. Leicester has a large South Asian population and a breast cancer unit with comprehensive data on diagnosed cancers. This study analysed the annual incidence of new breast cancer diagnoses in females from 1998 to 2009 to determine any changes in recent years.

METHODS

Ethnicity was known in over 98% of cases. Population denominators were based on published figures for 2001 and 2011, projected back to 1998. Age-adjusted directly standardised incidence rates were determined by ethnicity and broken down by invasive status and screening classification. Incidence rates were analysed using logistic regression in order to identify statistically significant effects of age, ethnicity, deprivation and year of diagnosis. Interactions with invasive status and screening classification were also investigated.

RESULTS

At the start of the study period South Asian incidence was estimated to be 45% of that of the white population (p<0.001); by the end of the period the difference was still significant (p=0.022) but smaller, at 17%.

CONCLUSION

South Asians should no longer be considered at low risk of breast cancer.

No socioeconomic inequalities in ovarian cancer survival within two randomised clinical trials

BACKGROUND

Ovarian cancer is the leading cause of death among cancers of the female genital tract, with poor outcomes despite chemotherapy. There was a persistent socioeconomic gradient in 1-year survival in England and Wales for more than 3 decades (1971-2001). Inequalities in 5-year survival persisted for more than 20 years but have been smaller for women diagnosed around 2000. We explored one possible explanation.

METHODS

We analysed data on 1406 women diagnosed with ovarian cancer during 1991-1998 and recruited to one of two randomised clinical trials. In the second International Collaborative Ovarian Neoplasm (ICON2) trial, women diagnosed between 1991 and 1996 were randomised to receive either the three-drug combination cyclophosphamide, doxorubicin and cisplatin (CAP) or single-agent carboplatin given at optimal dose. In the ICON3 trial, women diagnosed during 1995-1998 were randomised to receive either the same treatments as ICON2, or paclitaxel plus carboplatin.Relative survival at 1, 5 and 10 years was estimated for women in five categories of socioeconomic deprivation. The excess hazard of death over and above background mortality was estimated by fitting multivariable regression models with Poisson error structure and a dedicated link function in a generalised linear model framework, adjusting for the duration of follow-up and the confounding effects of age, Federation of Gynecology and Obstetrics (FIGO) stage and calendar period.

RESULTS

Unlike women with ovarian cancer in the general population, no statistically significant socioeconomic gradient was seen for women with ovarian cancer treated in the two randomised controlled trials. The deprivation gap in 1-year relative survival in the general population was statistically significant at -6.7% (95% CI (-8.1, -5.3)), compared with -3.6% (95% CI (-10.4, +3.2)) in the trial population.

CONCLUSIONS

Although ovarian cancer survival is significantly lower among poor women than rich women in England and Wales, there was no evidence of an association between socioeconomic deprivation and survival among women with ovarian cancer who were treated and followed up consistently in two well-conducted randomised controlled trials. We conclude that the persistent socioeconomic gradient in survival among women with ovarian cancer, at least for 1-year survival, may be due to differences in access to treatment and standards of care.