Socioeconomic inequalities in breast cancer incidence and mortality in Europe-a systematic review and meta-analysis

Socioeconomic inequality in prostate cancer diagnostics, primary treatment, rehabilitation, and mortality in Sweden

We designed a nationwide study to investigate the association between socioeconomic factors (household income and education) and different aspects of prostate cancer care, considering both individual- and neighbourhood-level variables. Data were obtained from Prostate Cancer data Base Sweden (PCBaSe), a research database with data from several national health care registers including clinical characteristics and treatments for nearly all men diagnosed with prostate cancer in Sweden. Four outcomes were analysed: use of pre-biopsy magnetic resonance imaging (MRI) in 2018-2020 (n = 11,843), primary treatment of high-risk non-metastatic disease in 2016-2020 (n = 6633), rehabilitation (≥2 dispensed prescriptions for erectile dysfunction within 1 year from surgery in 2016-2020, n = 6505), and prostate cancer death in 7770 men with high-risk non-metastatic disease diagnosed in 2010-2016. Unadjusted and adjusted odds and hazard ratios (OR/HRs) with 95% confidence intervals (CIs) were calculated. Adjusted odds ratio (ORs) comparing low versus high individual education were 0.74 (95% CI 0.66-0.83) for pre-biopsy MRI, 0.66 (0.54-0.81) for primary treatment, and 0.82 (0.69-0.97) for rehabilitation. HR gradients for prostate cancer death were significant on unadjusted analysis only (low vs. high individual education HR 1.41, 95% CI 1.17-1.70); co-variate adjustments markedly attenuated the gradients (low vs. high individual education HR 1.10, 95% CI 0.90-1.35). Generally, neighbourhood-level analyses showed weaker gradients over the socioeconomic strata, except for pre-biopsy MRI. Socioeconomic factors influenced how men were diagnosed with prostate cancer in Sweden but had less influence on subsequent specialist care. Neighbourhood-level socioeconomic data are more useful for evaluating inequality in diagnostics than in later specialist care.

[Impact of precariousness on breast cancer care in the Île-de-France region: Results of the DESSEIN study]

INTRODUCTION

Precariousness has been associated with an increase in breast cancer mortality, but the links between precariousness, stage at diagnosis and care pathways are little explored. The objective of the DESSEIN study was to assess the impact of precariousness on disease and care pathways.

METHODS

Prospective observational study in Île-de-France comparing precarious and non-precarious patients consulting for breast cancer and followed for 1 year.

RESULTS

In total, 875 patients were included between 2016 and 2019 in 19 institutions: 543 non-precarious patients and 332 precarious patients. Precarious patients had a more advanced stage at diagnosis (55% T1 vs. 63%, 30% N+ vs 19%, P=0.0006), had a higher risk of not receiving initially planned treatment (4 vs. 1%, P=0.004), and participated less in clinical trials (5 vs. 9%, P=0.03). Non-use of supportive oncology care was 2 times more frequent among patients in precarious situations (P<0.001). During treatment, 33% of deprived patients reported a loss of income, compared with 24% of non-deprived patients (P<0.001). At 12 months from diagnosis, lay-offs were 2 times more frequent in precarious patients (P=0.0001).

DISCUSSION

Precariousness affects all stages of the cancer history and care pathway. Particular attention needs to be paid to vulnerable populations, considering issues of accessibility and affordability of care, health literacy and possible implicit bias from the care providers.

Social Characteristics and Adherence to Adjuvant Endocrine Therapy in Premenopausal Women With Breast Cancer

PURPOSE

Social characteristics, including cohabitation/marital status and socioeconomic position (SEP)-education level, employment status, and income-influence breast cancer prognosis. We investigated the impact of these social characteristics on adherence to adjuvant endocrine therapy (AET) from treatment initiation to 5 years after diagnosis.

METHODS

We assembled a nationwide, population-based cohort of premenopausal women diagnosed in Denmark with stage I-III, estrogen receptor-positive breast cancer during 2002-2011. We ascertained prediagnostic social characteristics from national registries. AET adherence was based on information from the Danish Breast Cancer Group and operationalized as (1) adherence trajectories (from group-based trajectory modeling) and (2) early discontinuation. We computed odds ratios (ORs) and associated 95% CI to estimate the association of cohabitation and SEP with AET adherence using multinomial and logistic regression models adjusted according to directed acyclic graphs.

RESULTS

Among 4,353 patients, we identified three adherence trajectories-high adherence (57%), slow decline (36%), and rapid decline (6.9%). Compared with cohabiting women, those living alone had higher ORs of slow (1.26 [95% CI, 1.08 to 1.46]) or rapid decline (1.66 [95% CI, 1.27 to 2.18]) versus high adherence. The corresponding ORs for women not working versus employed women were 1.22 (95% CI, 1.02 to 1.45) and 1.76 (95% CI, 1.30 to 2.38). For early discontinuation (17%), the ORs were 1.48 (95% CI, 1.23 to 1.78) for living alone and 1.44 (95% CI, 1.17 to 1.78) for women not working.

CONCLUSION

Adherence to AET was lower among women living alone or unemployed than cohabiting or employed women, respectively. These women may benefit from support programs to enhance AET adherence.

EBCC-14 manifesto: Addressing disparities in access to innovation for patients with metastatic breast cancer across Europe

The European Breast Cancer Council (EBCC) traditionally identifies controversies or major deficiencies in the management of patients with breast cancer and selects a multidisciplinary expert team to collaborate in setting crucial principles and recommendations to improve breast cancer care. The 2024 EBCC manifesto focuses on disparities in the care of patients with metastatic breast cancer. There are several reasons for existing disparities both between and within countries. Our recommendations aim to address the stigma of metastatic disease, which has led to significant disparities in access to innovative care regardless of the gross national income of a country. These recommendations are for different stakeholders to promote the care of patients with metastatic breast cancer across Europe and worldwide.

Familial adversity: association with discontinuation of adjuvant hormone therapy and breast cancer prognosis

BACKGROUND

Many studies have examined patient-related factors affecting adjuvant hormone therapy adherence in patients with breast cancer. Our study aimed to examine associations of family-related factors with adjuvant hormone therapy discontinuation and breast cancer-specific mortality.

METHODS

By cross-linking 7 Swedish health registers, we performed a cohort study that included all patients with breast cancer who initiated adjuvant hormone therapy during 2006-2019 in Sweden (N = 10 701). A group-based multitrajectory model was used to identify familial adversity groups based on 3 dimensions: material deprivation, negative family dynamics, and loss or threat of loss. Cox proportional hazard models were used to investigate associations of familial adversity with hormone therapy discontinuation and breast cancer-specific mortality.

RESULTS

We identified 5 distinctive familial adversity groups among the cohort participants. Compared with women who had low familial adversity, higher risks to discontinue adjuvant hormone therapy were observed among women with material deprivation (hazard ratio [HR] = 1.31, 95% confidence interval [CI] = 1.20 to 1.43), negative family dynamics (HR = 1.16, 95% CI = 1.06 to 1.28), loss or threat of loss (HR = 1.15, 95% CI = 1.00 to 1.32), or high familial adversity (HR = 1.53, 95% CI = 1.40 to 1.68). Furthermore, women with material deprivation (HR = 1.37, 95% CI = 1.05 to 1.79), negative family dynamics (HR = 1.41, 95% CI = 1.01 to 1.97), or high adversity (HR = 1.67, 95% CI = 1.26 to 2.23) were at higher risk of dying from breast cancer.

CONCLUSION

Familial adversity is associated with a higher risk of adjuvant hormone therapy discontinuation and breast cancer-specific mortality. Family-related factors identified in our study may help identify high-risk patients for interventions to prevent treatment discontinuation and subsequently improve breast cancer outcomes.

Trends in socioeconomic inequalities in breast cancer mortality in Canada: 1992-2019

PURPOSE

Breast cancer is the second leading cause of death from cancer among Canadian females. This study aimed to quantify and assess trends in education and income inequalities in the mortality rate of breast cancer in Canada from 1992 to 2019.

METHODS

We constructed a census division-level dataset pooled from the Canadian Vital Death Statistics Database (CVSD), the Canadian Census of the Population (CCP), and the National Household Survey (NHS) to examine trends in education and income inequalities in the mortality rate of breast cancer in Canada over the study period. The age-standardized Concentration index (C) was used to quantify income and education inequalities in breast cancer mortality over time.

RESULTS

The national crude mortality rate of breast cancer has decreased in Canada from 1992 to 2019, with Alberta, British Columbia, Manitoba, Ontario, Prince Edward Island, and Quebec having the greatest decreases in mortality rate. The age-standardized C for education and income inequalities were always negative for all the study years, meaning that the mortality rate of breast cancer was higher among less-educated and poorer females. Moreover, the results indicate a growing trend in the concentration of breast cancer mortality among females with lower income and education from 1992 to 2019.

CONCLUSION

The increasing concentration of breast cancer mortality among low socioeconomic status females remains a challenge in Canada. Continuous efforts are needed within Canadian healthcare system to improve the prevention and treatment of breast cancer for this population.

Prognostic Factors Associated with Breast Cancer-Specific Survival from 1995 to 2022: A Systematic Review and Meta-Analysis of 1,386,663 Cases from 30 Countries

Breast cancer is the fifth-ranked cancer globally. Despite early diagnosis and advances in treatment, breast cancer mortality is increasing. This meta-analysis aims to examine all possible prognostic factors that improve/deteriorate breast cancer-specific survival. MEDLINE, PubMed, ScienceDirect, Ovid, and Google Scholar were systematically searched until September 16, 2023. The retrieved studies from 1995 to 2022 accumulated 1,386,663 cases from 30 countries. A total of 13 out of 22 prognostic factors were significantly associated with breast cancer-specific survival. A random-effects model provided a pooled estimate of the top five poorest prognostic factors, including Stage 4 (HR = 12.12; 95% CI: 5.70, 25.76), followed by Stage 3 (HR = 3.42, 95% CI: 2.51, 4.67), a comorbidity index ≥ 3 (HR = 3.29; 95% CI: 4.52, 7.35), the poor differentiation of cancer cell histology (HR = 2.43; 95% CI: 1.79, 3.30), and undifferentiated cancer cell histology (HR = 2.24; 95% CI: 1.66, 3.01). Other survival-reducing factors include positive nodes, age, race, HER2-receptor positivity, and overweight/obesity. The top five best prognostic factors include different types of mastectomies and breast-conserving therapies (HR = 0.56; 95% CI: 0.44, 0.70), medullary histology (HR = 0.62; 95% CI: 0.53, 0.72), higher education (HR = 0.72; 95% CI: 0.68, 0.77), and a positive estrogen receptor status (HR = 0.78; 95% CI: 0.65, 0.94). Heterogeneity was observed in most studies. Data from developing countries are still scarce.

Impact of neoadjuvant compared to adjuvant chemotherapy on prognosis in patients with hormone-receptor positive / HER2-negative breast cancer: A propensity score matching population-based study

BACKGROUND

The aim of this population-based cohort study was to investigate the impact of neoadjuvant chemotherapy (NACT) compared to adjuvant chemotherapy in prognosis among patients with HR+/HER2 negative breast cancer.

METHOD

This population-based study utilized data from the research database BCBaSe 3.0, based on the Swedish National Quality breast cancer register, including all patients with breast cancer diagnosis in Sweden between 2008 and 2019. Propensity score matching approach was applied. The outcomes of interest consisted of distant-disease free (DDFS), breast-cancer specific (BCSS), and overall survival (OS).

RESULTS

In total, 14 459 patients were included in the study cohort of whom 2086 received NACT. After 1:1 propensity score matching (PSM), 1539 patients in each study group were available for analyses. No statistically significant difference in survival outcomes were observed between patients treated with NACT compared to those treated with adjuvant chemotherapy (Hazard Ratio (HR) for DDFS: 1.20; 95 % CI: 0.80-1.79; HR for BCSS: 1.16; 95 % CI: 0.54-2.49; HR for OS: 1.14; 95 % CI: 0.64-2.05).

CONCLUSION

In this population-based cohort study of patients with HR+/HER2-breast cancer, the use of NACT seems to be comparable to adjuvant chemotherapy in terms of prognosis, although non-inferiority cannot be proven by this study design. Until further evidence suggesting a survival benefit in favor of either treatment is available, NACT can be pursued when surgical-de-escalation is intended.

Social Representativeness and Intervention Adherence-A Systematic Review of Clinical Physical Activity Trials in Breast Cancer Patients

Objectives

Representativeness in physical activity randomised controlled trials (RCT) in breast cancer patients is essential to analyses of feasibility and validity considering privileged- social groups. A step-by-step exclusion of less privileged groups through the trial process could reinforce health inequality. This study aimed at examining representativeness in breast cancer (BC) physical activity trials, investigate associations between socio-economic status (SES) and intervention adherence, and explore associations between representativeness and the relationship between SES and intervention adherence.

Methods

Systematic, computerised searches were performed in PubMed, CINAHL, AMED, EMBASE and PsycINFO. Additional citation-based searches retrieved 37 articles. Distributions of education level, ethnicity, and marital status in study samples were compared to national populations data to estimate representativeness in less privileged groups.

Results

A preponderance of studies favoured educated, married and white patients. Only six studies reported SES-adherence associations, hampering conclusions on this relationship and possible associations between representativeness and an SES-adherence relationship.

Conclusion

Less educated, unmarried and non-white individuals may be underrepresented in BC physical activity RCTs, while SES-adherence associations in such trials are inconclusive. Unintentional social misrepresentations may indicate that disguised inequity warrants revived attention.

Socioeconomic Deprivation and Invasive Breast Cancer Incidence by Stage at Diagnosis: A Possible Explanation to the Breast Cancer Social Paradox

In this study, we assessed the influence of area-based socioeconomic deprivation on the incidence of invasive breast cancer (BC) in France, according to stage at diagnosis. All women from six mainland French departments, aged 15+ years, and diagnosed with a primary invasive breast carcinoma between 2008 and 2015 were included (n = 33,298). Area-based socioeconomic deprivation was determined using the French version of the European Deprivation Index. Age-standardized incidence rates (ASIR) by socioeconomic deprivation and stage at diagnosis were compared estimating incidence rate ratios (IRRs) adjusted for age at diagnosis and rurality of residence. Compared to the most affluent areas, significantly lower IRRs were found in the most deprived areas for all-stages (0.85, 95% CI 0.81-0.89), stage I (0.77, 95% CI 0.72-0.82), and stage II (0.84, 95% CI 0.78-0.90). On the contrary, for stages III-IV, significantly higher IRRs (1.18, 95% CI 1.08-1.29) were found in the most deprived areas. These findings provide a possible explanation to similar or higher mortality rates, despite overall lower incidence rates, observed in women living in more deprived areas when compared to their affluent counterparts. Socioeconomic inequalities in access to healthcare services, including screening, could be plausible explanations for this phenomenon, underlying the need for further research.

Breast cancer insights from Northern Israel: a comprehensive analysis of survival rates among Jewish and Arab women

This study investigates breast cancer survival rates between 2000 and 2022 in northern Israel, focusing on ethnicity, socioeconomic status, age at diagnosis, and the Charlson Comorbidity Index. Analyzing data from Clalit Health Services, we studied 8,431 breast cancer patients (6,395 Jewish, 2,036 Arab). We compared five- and ten-year survival rates across different demographics. Ethnicity showed a minor impact on survival (OR 1.12, 95% CI: 0.93 - 1.35). Socioeconomic status had a significant effect, with a higher level of improving survival (OR 2.50, 95% CI: 2.04 - 3.08). Age was crucial; women 18-39 had better survival than 60-100, but no significant difference was found between the 18-39 and 40-59 age groups [OR (CI 0.90 - 1.53, p = 0.231)]. For the Charlson Comorbidity Index, women with scores of 3-10 showed lower survival compared to scores of 0 and 1-2. There was a notable improvement in five-year survival rates among patients aged 18-59 diagnosed from 2009-2018 (90.7%) compared to 2000-2008 (86.9%) (p = 0.0046), but not in patients aged 60-100. The study highlights that socioeconomic status, age, and comorbidity scores are significant in determining survival rates for breast cancer. The improvement in survival rates for younger patients diagnosed more recently reflects advancements in treatment and care. This research provides valuable insights into the factors affecting breast cancer survival rates, underscoring the role of socioeconomic status, age, and comorbidities while also highlighting the progress in breast cancer treatment over recent years.

Causes and Risk Factors of Breast Cancer, What Do We Know for Sure? An Evidence Synthesis of Systematic Reviews and Meta-Analyses

Breast cancer affected more than 2.3 million women in 2022 and is the most diagnosed cancer among women worldwide. The incidence rates are greater in developed regions and are significantly higher among women with higher education and socioeconomic status. Therefore, it is reasonable to assume that the way women live their lives may impact their risk of being diagnosed with breast cancer. This systematic review aimed to identify what is known about the causes and risk factors of breast cancer, excluding genetic causes. A comprehensive systematic search identified 2387 systematic reviews, 122 were included and six overall themes identified. In our "top list" with the 36 most important findings, a study of breast density had the highest effect size for increasing the risk of breast cancer, and a high sex-hormone-binding globulin level was the most protective factor. Many of the included studies investigating the same topics had conflicting results. The conclusion from this evidence synthesis reveals a lack of consensus of factors associated with the causes and risk of breast cancer. These findings suggest that recommendations about lifestyle and breast cancer should be made with caution.

Cancer incidence trends in New York State and associations with common population-level exposures 2010-2018: an ecological study

The impact of common environmental exposures in combinations with socioeconomic and lifestyle factors on cancer development, particularly for young adults, remains understudied. Here, we leveraged environmental and cancer incidence data collected in New York State at the county level to examine the association between 31 exposures and 10 common cancers (i.e., lung and bronchus, thyroid, colorectal, kidney and renal pelvis, melanoma, non-Hodgkin lymphoma, and leukemia for both sexes; corpus uteri and female breast cancer; prostate cancer), for three age groups (25-49, 50-69, and 70-84 year-olds). For each cancer, we stratified by age group and sex, and applied regression models to examine the associations with multiple exposures simultaneously. The models included 642,013 incident cancer cases during 2010-2018 and found risk factors consistent with previous reports (e.g., smoking and physical inactivity). Models also found positive associations between ambient air pollutants (ozone and PM2.5) and prostate cancer, female breast cancer, and melanoma of the skin across multiple population strata. Additionally, the models were able to better explain the variation in cancer incidence data among 25-49 year-olds than the two older age groups. These findings support the impact of common environmental exposures on cancer development, particularly for younger age groups.

[Trend in breast cancer mortality rate among women aged 20 years or older in Brazil, 2005-2019]

The aim is to analyze the trend in breast cancer mortality rates and its correlation with the socioeconomic development status in Brazil. It involved an ecological time series study carried out in the 26 units of the federation, Federal District and regions of Brazil. Data sources included the Mortality Information System (number of deaths), the Brazilian Institute of Geography and Statistics (resident population) and the study of the Global Burden of Disease (Socio-demographic Index - SDI). Data from 2005 to 2019 were used. The trend was analyzed using Prais-Winsten regression models. The relationship between the mortality rate and the SDI was analyzed using Spearman's correlation coefficient. During the study period, 207,683 deaths from breast cancer occurred. The average standardized mortality rate was 19.95 deaths per 100,000 women in Brazil. All the regions of Brazil showed an increasing trend in mortality. Of the total federative units, 22 showed an increasing trend. There was a positive relationship between the mortality rate and the SDI. The standardized mortality rate for breast cancer showed an increasing trend in Brazil, in all regions and in most states. There was a direct association between mortality and SDI, indicating a greater magnitude in more developed regions.

Survival Outcomes in Older Women with Oestrogen-Receptor-Positive Early-Stage Breast Cancer: Primary Endocrine Therapy vs. Surgery by Comorbidity and Frailty Levels

Primary endocrine therapy (PET) offers non-surgical treatment for older women with early-stage breast cancer who are unsuitable for surgery due to frailty or comorbidity. This research assessed all-cause and breast cancer-specific mortality of PET vs. surgery in older women (≥70 years) with oestrogen-receptor-positive early-stage breast cancer by frailty and comorbidity levels. This study used UK secondary data to analyse older female patients from 2000 to 2016. Patients were censored until 31 May 2019 and grouped by the Charlson comorbidity index (CCI) and hospital frailty risk score (HFRS). Cox regression models compared all-cause and breast cancer-specific mortality between PET and surgery within each group, adjusting for patient preferences and covariates. Sensitivity analyses accounted for competing risks. There were 23,109 patients included. The hazard ratio (HR) comparing PET to surgery for overall survival decreased significantly from 2.1 (95%CI: 2.0, 2.2) to 1.2 (95%CI: 1.1, 1.5) with increasing HFRS and from 2.1 (95%CI: 2.0, 2.2) to 1.4 (95%CI 1.2, 1.7) with rising CCI. However, there was no difference in BCSM for frail older women (HR: 1.2; 0.9, 1.9). There were no differences in competing risk profiles between other causes of death and breast cancer-specific mortality with PET versus surgery, with a subdistribution hazard ratio of 1.1 (0.9, 1.4) for high-level HFRS (p = 0.261) and CCI (p = 0.093). Given limited survival gains from surgery for older patients, PET shows potential as an effective option for frail older women with early-stage breast cancer. Despite surgery outperforming PET, surgery loses its edge as frailty increases, with negligible differences in the very frail.

Decline in the Incidence of Distant Recurrence of Breast Cancer: A Population-Based Health Record Linkage Study, Australia 2001-2016

BACKGROUND

We investigated differences in cumulative incidence of first distant recurrence (DR) following non-metastatic breast cancer over a time period when new adjuvant therapies became available in Australia.

METHODS

We conducted a health record linkage study of females with localized (T1-3N0) or regional (T4 or N+) breast cancer in the New South Wales Cancer Registry in 2001 to 2002 and 2006 to 2007. We linked cancer registry records with administrative records from hospitals, dispensed medicines, radiotherapy services, and death registrations to estimate the 9-year cumulative incidence of DR and describe use of adjuvant treatment.

RESULTS

The study included 13,170 women (2001-2002 n = 6,338, 2006-2007 n = 6,832). The 9-year cumulative incidence of DR was 3.6% [95% confidence interval (CI), 2.3%-4.9%] lower for 2006-2007 diagnoses (15.0%) than 2001-2002 (18.6%). Differences in the annual hazard of DR between cohorts were largest in year two. DR incidence declined for localized and regional disease. Decline was largest for ages <40 years (absolute difference, 14.4%; 95% CI, 8.3%-20.6%), whereas their use of adjuvant chemotherapy (2001-2002 49%, 2006-2007 75%) and HER2-targeted therapy (2001-2002 0%, 2006-2007 16%) increased. DR did not decline for ages ≥70 years (absolute difference, 0.9%; 95% CI, -3.6%-1.8%) who had low use of adjuvant chemotherapy and HER2-targeted therapy.

CONCLUSIONS

This whole-of-population study suggests that DR incidence declined over time. Decline was largest for younger ages, coinciding with changes to adjuvant breast cancer therapy.

IMPACT

Study findings support the need for trials addressing questions relevant to older people and cancer registry surveillance of DR to inform cancer control programs.

Socioeconomic and geographic disparities of breast cancer incidence according to stage at diagnosis in France

PURPOSE

Low socioeconomic background (SB) has been associated with lower breast cancer (BC) incidence and higher BC mortality. One explanation of this paradox is the higher frequency of advanced BC observed in deprived women. However, it is still unclear if SB affects similarly BC incidence. This study investigated the link between SB and early/advanced BC incidence from Loire-Atlantique/Vendee Cancer registry data (France).

MATERIALS AND METHODS

Fourteen thousand three hundred fifty three women living in the geographic area covered by the registry and diagnosed with a primary BC in 2008-2015 were included. SB was approached by a combination of two ecological indexes (French European Deprivation Index and urban/rural residence place). Mixed effects logistic and Poisson regressions were used, respectively, to estimate the odds of advanced (stage ≥ II) BC and the ratio of incidence rates of early (stage 0-I) and advanced BC according to SB, overall and by age group (< 50, 50-74, ≥ 75).

RESULTS

Compared to women living in affluent-urban areas, women living in deprived-urban and deprived-rural areas had a higher proportion of advanced BC [respectively, OR = 1.11 (1.01-1.22), OR = 1.60 (1.25-2.06)] and lower overall (from - 6 to - 15%) and early (from - 9 to - 31%) BC incidences rates Advanced BC incidence rates were not influenced by SB. These patterns were similar in women under 75 years, especially in women living in deprived-rural areas. In the elderly, no association between SB and BC frequency/incidence rates by stage was found.

CONCLUSION

Although advanced BC was more frequent in women living in deprived and rural areas, SB did not influence advanced BC incidence. Therefore, differences observed in overall BC incidence according to SB were only due to higher incidence of early BC in affluent and urban areas. Future research should confirm these results in other French areas.

Overadjustment bias in systematic reviews and meta-analyses of socio-economic inequalities in health: a meta-research scoping review

BACKGROUND

Overadjustment bias occurs when researchers adjust for an explanatory variable on the causal pathway from exposure to outcome, which leads to biased estimates of the causal effect of the exposure. This meta-research review aimed to examine how previous systematic reviews and meta-analyses of socio-economic inequalities in health have managed overadjustment bias.

METHODS

We searched Medline and Embase until 16 April 2021 for systematic reviews and meta-analyses of observational studies on associations between individual-level socio-economic position and health outcomes in any population. A set of criteria were developed to examine methodological approaches to overadjustment bias adopted by included reviews (rated Yes/No/Somewhat/Unclear).

RESULTS

Eighty-four reviews were eligible (47 systematic reviews, 37 meta-analyses). Regarding approaches to overadjustment, whereas 73% of the 84 reviews were rated as Yes for clearly defining exposures and outcomes, all other approaches were rated as Yes for <55% of reviews; for instance, 5% clearly defined confounders and mediators, 2% constructed causal diagrams and 35% reported adjusted variables for included studies. Whereas only 2% included overadjustment in risk of bias assessment, 54% included confounding. Of the 37 meta-analyses, 16% conducted sensitivity analyses related to overadjustment.

CONCLUSIONS

Our findings suggest that overadjustment bias has received insufficient consideration in systematic reviews and meta-analyses of socio-economic inequalities in health. This is a critical issue given that overadjustment bias is likely to result in biased estimates of health inequalities and accurate estimates are needed to inform public health interventions. There is a need to highlight overadjustment bias in review guidelines.

Isolating the effect of confounding from the observed survival benefit of screening participants - a methodological approach illustrated by data from the German mammography screening programme

BACKGROUND

Mammography screening programmes (MSP) aim to reduce breast cancer mortality by shifting diagnoses to earlier stages. However, it is difficult to evaluate the effectiveness of current MSP because analyses can only rely on observational data, comparing women who participate in screening with women who do not. These comparisons are subject to several biases: one of the most important is self-selection into the MSP, which introduces confounding and is difficult to control for. Here, we propose an approach to quantify confounding based on breast cancer survival analyses using readily available routine data sources.

METHODS

Using data from the Cancer Registry of North Rhine-Westphalia, Germany, we estimate the relative contribution of confounding to the observed survival benefit of participants of the German MSP. This is accomplished by comparing non-participants, participants with screen-detected and participants with interval breast cancers for the endpoints "death from breast cancer" and "death from all causes other than breast cancer" - the latter being assumed to be unrelated to any MSP effect. By using different contrasts, we eliminate the effects of stage shift, lead and length time bias. The association of breast cancer detection mode with survival is analysed using Cox models in 68,230 women, aged 50-69 years, with breast cancer diagnosed in 2006-2014 and followed up until 2018.

RESULTS

The hazard of dying from breast cancer was lower in participants with screen-detected cancer than in non-participants (HR = 0.21, 95% CI: 0.20-0.22), but biased by lead and length time bias, and confounding. When comparing participants with interval cancers and non-participants, the survival advantage was considerably smaller (HR = 0.62, 95% CI: 0.58-0.66), due to the elimination of stage shift and lead time bias. Finally, considering only mortality from causes other than breast cancer in the latter comparison, length time bias was minimised, but a survival advantage was still present (HR = 0.63, 95% CI: 0.56-0.70), which we attribute to confounding.

CONCLUSIONS

This study shows that, in addition to stage shift, lead and length time bias, confounding is an essential component when comparing the survival of MSP participants and non-participants. We further show that the confounding effect can be quantified without explicit knowledge of potential confounders by using a negative control outcome.

Development and quality appraisal of a new English breast screening linked data set as part of the age, test threshold, and frequency of mammography screening (ATHENA-M) study

OBJECTIVES

To build a data set capturing the whole breast cancer screening journey from individual breast cancer screening records to outcomes and assess data quality.

METHODS

Routine screening records (invitation, attendance, test results) from all 79 English NHS breast screening centres between January 1, 1988 and March 31, 2018 were linked to cancer registry (cancer characteristics and treatment) and national mortality data. Data quality was assessed using comparability, validity, timeliness, and completeness.

RESULTS

Screening records were extracted from 76/79 English breast screening centres, 3/79 were not possible due to software issues. Data linkage was successful from 1997 after introduction of a universal identifier for women (NHS number). Prior to 1997 outcome data are incomplete due to linkage issues, reducing validity. Between January 1, 1997 and March 31, 2018, a total of 11 262 730 women were offered screening of whom 9 371 973 attended at least one appointment, with 139 million person-years of follow-up (a median of 12.4 person years for each woman included) with 73 810 breast cancer deaths and 1 111 139 any-cause deaths. Comparability to reference data sets and internal validity were demonstrated. Data completeness was high for core screening variables (>99%) and main cancer outcomes (>95%).

CONCLUSIONS

The ATHENA-M project has created a large high-quality and representative data set of individual women's screening trajectories and outcomes in England from 1997 to 2018, data before 1997 are lower quality.

ADVANCES IN KNOWLEDGE

This is the most complete data set of English breast screening records and outcomes constructed to date, which can be used to evaluate and optimize screening.

Machine learning prediction of pathological complete response and overall survival of breast cancer patients in an underserved inner-city population

BACKGROUND

Generalizability of predictive models for pathological complete response (pCR) and overall survival (OS) in breast cancer patients requires diverse datasets. This study employed four machine learning models to predict pCR and OS up to 7.5 years using data from a diverse and underserved inner-city population.

METHODS

Demographics, staging, tumor subtypes, income, insurance status, and data from radiology reports were obtained from 475 breast cancer patients on neoadjuvant chemotherapy in an inner-city health system (01/01/2012 to 12/31/2021). Logistic regression, Neural Network, Random Forest, and Gradient Boosted Regression models were used to predict outcomes (pCR and OS) with fivefold cross validation.

RESULTS

pCR was not associated with age, race, ethnicity, tumor staging, Nottingham grade, income, and insurance status (p > 0.05). ER-/HER2+ showed the highest pCR rate, followed by triple negative, ER+/HER2+, and ER+/HER2- (all p < 0.05), tumor size (p < 0.003) and background parenchymal enhancement (BPE) (p < 0.01). Machine learning models ranked ER+/HER2-, ER-/HER2+, tumor size, and BPE as top predictors of pCR (AUC = 0.74-0.76). OS was associated with race, pCR status, tumor subtype, and insurance status (p < 0.05), but not ethnicity and incomes (p > 0.05). Machine learning models ranked tumor stage, pCR, nodal stage, and triple-negative subtype as top predictors of OS (AUC = 0.83-0.85). When grouping race and ethnicity by tumor subtypes, neither OS nor pCR were different due to race and ethnicity for each tumor subtype (p > 0.05).

CONCLUSION

Tumor subtypes and imaging characteristics were top predictors of pCR in our inner-city population. Insurance status, race, tumor subtypes and pCR were associated with OS. Machine learning models accurately predicted pCR and OS.

Disparities in Cancer Incidence across Income Levels in South Korea

BACKGROUND

Recent nationwide studies of disparities in cancer incidence by income are scarce in Korea. This study investigated such disparities in cancer incidence and the stage at cancer diagnosis across income groups in Korea.

METHODS

This study utilized data from a national cancer database, specifically focusing on cases recorded in the year 2018. Income levels were categorized into quintiles according to the insurance premium paid in addition to the Medicaid benefit. The slope index of inequality (SII) and relative index of inequality (RII) were used to measure absolute and relative differences in cancer incidence by income. A multivariable logistic regression was performed to estimate the risk of a distant stage at cancer diagnosis.

RESULTS

The total number of cases of incident cancer was 223,371 (men: 116,320, women: 107,051) with shares of the total of 29.5% (5Q), 20.4% (4Q), 16.0% (3Q), 13.5% (2Q), 15.6% (1Q), and 5% (Medicaid). The most common cancer type was thyroid cancer, followed by gastric and colorectal cancers. The age-standardized incidence rate for all cancers was lowest in the highest income group, but the SII was not statistically significant (SII: -35.7), and the RII was -0.07. Colorectal and cervical cancers had lower incidence rates for higher income groups, while thyroid and prostate cancers had higher incidence rates for higher income groups. The odds ratio for a distant stage at diagnosis for all cancers increased for lower income groups relative to 5Q.

CONCLUSIONS

Disparities in cancer incidence in a Korean population differed by cancer type, and lower income was a significant predictor of a distant stage at diagnosis for cancers overall. These results emphasize the need for further study of the underlying causes of disparities in cancer incidence and the stage at diagnosis, as well as the need for interventions to mitigate these disparities.

Exploring the geospatial epidemiology of breast cancer in Iran: identifying significant risk factors and spatial patterns for evidence-based prevention strategies

BACKGROUND

Breast Cancer (BC) is a formidable global health challenge, and Iran is no exception, with BC accounting for a significant proportion of women's malignancies. To gain deeper insights into the epidemiological characteristics of BC in Iran, this study employs advanced geospatial techniques and feature selection methods to identify significant risk factors and spatial patterns associated with BC incidence.

METHODS

Using rigorous statistical methods, geospatial data from Iran, including cancer-related, sociodemographic, healthcare infrastructure, environmental, and air quality data at the provincial level, were meticulously analyzed. Age-standardized incidence rates (ASR) are calculated, and different regression models are used to identify significant variables associated with BC incidence. Spatial analysis techniques, including global and local Moran's index, geographically weighted regression, and Emerging hotspot analysis, were utilized to examine geospatial patterns, identify clustering and hotspots, and assess spatiotemporal distribution of BC incidence.

RESULTS

The findings reveal that BC predominantly affects women (98.03%), with higher incidence rates among those aged 50 to 79. Isfahan (ASR = 26.1) and Yazd (ASR = 25.7) exhibit the highest rates. Significant predictors of BC incidence, such as marriage, tertiary education attainment rate, physician-to-population ratio, and PM2.5 air pollution, are identified through regression models.

CONCLUSION

The study's results provide valuable information for the development of evidence-based prevention strategies to reduce the burden of BC in Iran. The findings underscore the importance of early detection, health education campaigns, and targeted interventions in high-risk clusters and adjacent regions. The geospatial insights generated by this study have implications for policy-makers, researchers, and public health practitioners, facilitating the formulation of effective BC prevention strategies tailored to the unique epidemiological patterns in Iran.

Effects of organized screening programs on breast cancer screening, incidence, and mortality in Europe

We link data on regional Organized Screening Programs (OSPs) throughout Europe with survey data and population-based cancer registries to estimate effects of OSPs on breast cancer screening (mammography), incidence, and mortality. Identification is from regional variation in the existence and timing of OSPs, and in their age-eligibility criteria. We estimate that OSPs, on average, increase mammography by 25 percentage points, increase breast cancer incidence by 16% five years after the OSPs implementation, and reduce breast cancer mortality by about 10% ten years after.

Trends in cancer incidence by socioeconomic deprivation in Germany in 2007 to 2018: An ecological registry-based study

Age-standardized cancer incidence has decreased over the last years for many cancer sites in developed countries. Whether these trends led to narrowing or widening socioeconomic inequalities in cancer incidence is unknown. Using cancer registry data covering 48 million inhabitants in Germany, the ecological association between age-standardized total and site specific (colorectal, lung, prostate and breast) cancer incidence in 2007 to 2018 and a deprivation index on district level (aggregated to quintiles) was investigated. Incidence in the most and least deprived districts were compared using Poisson models. Average annual percentage changes (AAPCs) and differences in AAPCs between deprivation quintiles were assessed using Joinpoint regression analyses. Age-standardized incidence decreased strongly between 2007 and 2018 for total cancer and all cancer sites (except female lung cancer), irrespective of the level of deprivation. However, differences in the magnitude of trends across deprivation quintiles resulted in increasing inequalities over time for total cancer, colorectal and lung cancer. For total cancer, the incidence rate ratio between the most and least deprived quintile increased from 1.07 (95% confidence interval: 1.01-1.12) to 1.23 (1.12-1.32) in men and from 1.07 (1.01-1.13) to 1.20 (1.14-1.26) in women. Largest inequalities were observed for lung cancer with 82% (men) and 88% (women) higher incidence in the most vs the least deprived regions in 2018. The observed increase in inequalities in cancer incidence is in alignment with trends in inequalities in risk factor prevalence and partly utilization of screening. Intervention programs targeted at socioeconomically deprived and urban regions are highly needed.

Survival in patients diagnosed with melanoma in situ compared to the general population. A Swedish population-based matched cohort study

Background

The incidence of melanoma in situ (MIS) is increasing even more rapidly than the incidence of cutaneous malignant melanoma (CMM). No previous studies have in detail investigated the survival in individuals diagnosed with MIS compared to the general population.

Methods

This population-based study included individuals with MIS diagnosed in Sweden between 2001 and 2010 and randomly selected MIS-free comparators matched on age, sex and county of residence. Exclusion criterion was a previous CMM. Data on socioeconomic status (SES) including educational level, income and marital status, comorbidity and cause of death were obtained from population-based registers. Overall survival (OS) was estimated by the Kaplan-Meier method. The mortality risk adjusted for SES and comorbidity was assessed by multivariable Cox regression analyses.

Findings

The survival analyses included 7963 cases and 39,662 comparators. Median age at MIS diagnosis were 63 (IQR 50-75) and 67 (IQR 57-76) years in women and men respectively. Median follow-up time was 120 months (IQR 102-152 months). In individuals with MIS, the ten-year OS was 77% (95% CI 0.76-0.78) compared to 72% (95% CI 0.72-0.73) in comparators. The MIS patients had a higher SES and lower comorbidity burden than the comparators. In a fully adjusted multivariable analysis, including 7772 cases and 38,103 comparators, the mortality was significantly lower in women with MIS (HR 0.88, 95% CI 0.82-0.94) compared to the background population. The corresponding estimate in men was HR 0.94 (95% CI 0.88-1.0). The risk of melanoma-related deaths during the study period was ten-fold higher in MIS patients.

Interpretation

Despite being at increased risk of developing CMM, MIS patients had a better OS compared to their matched comparators from the background population, findings which could not fully be explained by differences in SES and comorbidity. Our results are reassuring and should be communicated to patients who have been diagnosed with MIS.

Funding

Stiftelsen Onkologiska Klinikens i Uppsala Forskningsfond, Mats and Stefan Paulsson Trust, Medicon Village, Lund and Uppsala University Hospital (ALF).

Association of Socioeconomic Status Assessed by Areal Deprivation With Cancer Incidence and Detection by Screening in Miyagi, Japan Between 2005 and 2010

BACKGROUND

Previous studies have shown that socioeconomic factors are associated with cancer incidence and stage at diagnosis; however, relevant findings in Japan are limited. We examined the association between socioeconomic status and cancer incidence, stage at diagnosis, and detection status by screening, as assessed using the areal deprivation index (ADI), in population-based cancer registry data.

METHODS

A total of 79,816 cases, including stomach, colorectal, lung, female breast, and cervical cancer diagnosed in Miyagi Prefecture between 2005 and 2010, were analyzed. After calculating the ADI at the place of residence in each case, we examined the association between quintiles of ADI and age-adjusted incidence rates of all stages and advanced stages by sex and site using Poisson regression analysis. The association between the ADI and the proportion of screen-detected cancers was also examined using logistic regression analysis.

RESULTS

The age-adjusted incidence rates of all sites and lung cancer in men and lung cancer and cervical cancer in women tended to increase significantly in areas with a higher ADI. The age-adjusted incidence rates of advanced-stage cancers were significantly higher for all sites and lung cancer in both sexes, and for stomach and colorectal cancer in men. The proportion of screen-detected cancer tended to be significantly lower in areas with a higher ADI for stomach and colorectal cancer in men.

CONCLUSION

Our results indicate that socioeconomic disparities may affect cancer incidence and early diagnosis in Japan. These results suggest the importance of cancer control measures targeting people with low socioeconomic status in Japan.

Area Deprivation Index in Patients with Invasive Lobular Carcinoma of the Breast: Associations with Tumor Characteristics and Outcomes

BACKGROUND

Although investigators have shown associations between socioeconomic status (SES) and outcomes in breast cancer, there is a paucity of such data for invasive lobular carcinoma (ILC), the second most common type of breast cancer. Herein we evaluated the relationship between SES with tumor features and outcomes in stage I to III patients with ILC.

METHODS

We analyzed a prospectively maintained institutional ILC database and utilized the area deprivation index (ADI) to determine neighborhood adversity, an indicator of SES. We used Cox proportional hazards models in Stata 17.0 to evaluate relationships between ADI quintile (Q), race, body mass index (BMI), clinicopathologic features, treatment type, and event-free survival (EFS).

RESULTS

Of 804 patients with ILC, 21.4% lived in neighborhoods classified as ADI Q1 (least resource-deprived) and 19.7% in Q5 (most resource-deprived). Higher deprivation was significantly associated with larger tumor size (3.6 cm in Q5 vs. 3.1 cm in Q1), increased presence of lymphovascular invasion (8.9% in Q5 vs. 6.7% in Q1), and decreased use of adjuvant endocrine therapy (67.1% in Q5 vs. 73.6% in Q1). On multivariable analysis, tumor size, receptor subtypes, and omission of adjuvant endocrine therapy were associated with reduced EFS.

CONCLUSIONS

These data show that patients with ILC and higher ADI experience more aggressive tumors and differences in treatment. More data evaluating the complex relationships between these factors is needed to optimize outcomes for patients with ILC, regardless of SES.

IMPACT

ADI is associated with differences in patients with ILC.

The roles of chaplains in dispelling cancer myths in Nigeria: A narrative review

Background and Aims

The epidemiological burden of cancer in Africa, and Nigeria in particular, has been increasing significantly over the past few decades due to exposure to numerous risk factors as well as belief in various myths and misconceptions. Chaplains can play crucial roles in dispelling these myths and misconceptions about cancer among people. Therefore, this study seeks to review the epidemiological burden, risk factors, and myths relating to cancer and the roles of chaplains in dispelling cancer myths in Nigeria.

Methods

This paper is a narrative review that relied on secondary sources obtained through a thorough literature search of relevant articles on multiple electronic databases including PubMed, Google Scholar, and Web of Science. Published books, journal articles, and other published materials that were written in English were consulted in line with the objectives of this study. Both theoretical and empirical papers were used for this review.

Results

Cancers are associated with risk factors including exposure to chemicals, ultraviolet radiation, harmful tobacco and alcohol use, exposure to human papillomavirus (HPV), and these factors may vary with age, cultural beliefs (myths and misconceptions), and socioeconomic factors among others. Chaplains, however, have crucial roles to play in dispelling cancer myths in Nigeria. These roles include counseling, advocacy, education, and psycho-social support which may be limited by challenges such as spiritual ambiguity, inadequate training of healthcare providers and limited time/resources. These challenges can be addressed by training healthcare providers and incorporating chaplain practice in Nigerian healthcare.

Conclusion

The role of chaplains in dispelling cancer myths in Nigeria is crucial despite the numerous challenges. Hence, an urgent address of these challenges will be instrumental in ensuring effective chaplain practice in Nigeria.

Cancer inequalities in incidence and mortality in the State of São Paulo, Brazil 2001-17

BACKGROUND

Cancer disparities exist between and within countries; we sought to compare cancer-specific incidence and mortality according to area-level socioeconomic status (SES) in the State of São Paulo, Brazil.

METHODS

Cancer cases diagnosed 2003-2017 in the Barretos region and 2001-2015 in the municipality of São Paulo were obtained from the respective cancer registries. Corresponding cancer deaths were obtained from a Brazilian public government database. Age-standardized rates for all cancer combined and the six most common cancers were calculated by SES quartiles.

RESULTS

There were 14,628 cancer cases and 7513 cancer deaths in Barretos, and 472,712 corresponding cases and 194,705 deaths in São Paulo. A clear SES-cancer gradient was seen in São Paulo, with rates varying from 188.4 to 333.1 in low to high SES areas, respectively. There was a lesser social gradient for mortality, with rates in low to high SES areas ranging from 86.4 to 98.0 in Barretos, and from 99.2 to 100.1 in São Paulo. The magnitude of the incidence rates rose markedly with increasing SES in São Paulo city for colorectal, lung, female breast, and prostate cancer. Conversely, both cervical cancer incidence and mortality rose with lower levels of SES in both regions.

CONCLUSIONS

A clear SES association was seen for cancers of the prostate, female breast, colorectum, and lung for São Paulo. This study offers a better understanding of the cancer incidence and mortality profile according to SES within a highly populated Brazilian state.

Spatial Clusters of Cancer Mortality in Brazil: A Machine Learning Modeling Approach

Objectives: Our aim was to test if machine learning algorithms can predict cancer mortality (CM) at an ecological level and use these results to identify statistically significant spatial clusters of excess cancer mortality (eCM). Methods: Age-standardized CM was extracted from the official databases of Brazil. Predictive features included sociodemographic and health coverage variables. Machine learning algorithms were selected and trained with 70% of the data, and the performance was tested with the remaining 30%. Clusters of eCM were identified using SatScan. Additionally, separate analyses were performed for the 10 most frequent cancer types. Results: The gradient boosting trees algorithm presented the highest coefficient of determination (R 2 = 0.66). For total cancer, all algorithms overlapped in the region of Bagé (27% eCM). For esophageal cancer, all algorithms overlapped in west Rio Grande do Sul (48%-96% eCM). The most significant cluster for stomach cancer was in Macapá (82% eCM). The most important variables were the percentage of the white population and residents with computers. Conclusion: We found consistent and well-defined geographic regions in Brazil with significantly higher than expected cancer mortality.

Association Between Socioeconomic Status and Outcomes in Critical Care: A Systematic Review and Meta-Analysis

OBJECTIVES

Socioeconomic status is well established as a key determinant of inequalities in health outcomes. Existing literature examining the impact of socioeconomic status on outcomes in critical care has produced inconsistent findings. Our objective was to synthesize the available evidence on the association between socioeconomic status and outcomes in critical care.

DATA SOURCES

A systematic search of CINAHL, Ovid MEDLINE, and EMBASE was undertaken on September 13, 2022.

STUDY SELECTION

Observational cohort studies of adults assessing the association between socioeconomic status and critical care outcomes including mortality, length of stay, and functional outcomes were included. Two independent reviewers assessed titles, abstracts, and full texts against eligibility and quality criteria.

DATA EXTRACTION

Details of study methodology, population, exposure measures, and outcomes were extracted.

DATA SYNTHESIS

Thirty-eight studies met eligibility criteria for systematic review. Twenty-three studies reporting mortality to less than or equal to 30 days following critical care admission, and eight reporting length of stay, were included in meta-analysis. Random-effects pooled analysis showed that lower socioeconomic status was associated with higher mortality at less than or equal to 30 days following critical care admission, with pooled odds ratio of 1.13 (95% CIs, 1.05-1.22). Meta-analysis of ICU length of stay demonstrated no significant difference between socioeconomic groups. Socioeconomic status may also be associated with functional status and discharge destination following ICU admission.

CONCLUSIONS

Lower socioeconomic status was associated with higher mortality following admission to critical care.

Barriers to Implementation of Breast Cancer Risk Assessment: The Health Care Team Perspective

PURPOSE

To assess health care professionals' perceptions of barriers to the utilization of breast cancer risk assessment tools in the public health setting through a series of one-on-one interviews with health care team members.

METHODS

We conducted a cross-sectional qualitative study consisting of one-on-one semistructured telephone interviews with health care team members in the public health setting in the state of Tennessee between May 2020 and October 2020. An iterative inductive-deductive approach was used for qualitative analysis of interview data, resulting in the development of a conceptual framework to depict influences of provider behavior in the utilization of breast cancer risk assessment.

RESULTS

A total of 24 interviews were completed, and a framework of influences of provider behavior in the utilization of breast cancer risk assessment was developed. Participants identified barriers to the utilization of breast cancer risk assessment (knowledge and understanding of risk assessment tools, workflow challenges, and availability of personnel); patient-level barriers as perceived by health care team members (psychological, economic, educational, and environmental); and strategies to increase the utilization of breast cancer risk assessment at the provider level (leadership buy-in, training, supportive policies, and incentives) and patient level (improved communication and better understanding of patients' perceived cancer risk and severity of cancer).

CONCLUSIONS

Understanding barriers to implementation of breast cancer risk assessment and strategies to overcome these barriers as perceived by health care team members offers an opportunity to improve implementation of risk assessment and to identify a racially, geographically, and socioeconomically diverse population of young women at high risk for breast cancer.

Black Women's Perspectives on Breast Cancer Risk Assessment

PURPOSE

The aim of this study was to gather the perspectives of Black women on breast cancer risk assessment through a series of one-on-one interviews.

METHODS

The authors conducted a cross-sectional qualitative study consisting of one-on-one semistructured telephone interviews with Black women in Tennessee between September 2020 and November 2020. Guided by the Health Belief Model, qualitative analysis of interview data was performed in an iterative inductive and deductive approach and resulted in the development of a conceptual framework to depict influences on a woman's decision to engage with breast cancer risk assessment.

RESULTS

A total of 37 interviews were completed, and a framework of influences on a woman's decision to engage in breast cancer risk assessment was developed. Study participants identified several emerging themes regarding women's perspectives on breast cancer risk assessment and potential influences on women's decisions to engage with risk assessment. Much of women's decision context was based on risk appraisal (perceived severity of cancer and susceptibility of cancer), emotions (fear and trust), and perceived risks and benefits of having risk assessment. The decision was further influenced by modifiers such as communication, the risk assessment protocol, access to health care, knowledge, and health status. Perceived challenges to follow-up if identified as high risk also influenced women's decisions to pursue risk assessment.

CONCLUSIONS

Black women in this study identified several barriers to engagement with breast cancer risk assessment. Efforts to overcome these barriers and increase the use of breast cancer risk assessment can potentially serve as a catalyst to address existing breast cancer disparities. Continued work is needed to develop patient-centric strategies to overcome identified barriers.

Severity and risk factors of interval breast cancer in Queensland, Australia: a population-based study

BACKGROUND

Interval breast cancers (BC) are those diagnosed within 24 months of a negative mammogram. This study estimates the odds of being diagnosed with high-severity BC among screen-detected, interval, and other symptom-detected BC (no screening history within 2 years); and explores factors associated with being diagnosed with interval BC.

METHODS

Telephone interviews and self-administered questionnaires were conducted among women (n = 3,326) diagnosed with BC in 2010-2013 in Queensland. Respondents were categorised into screen-detected, interval, and other symptom-detected BCs. Data were analysed using logistic regressions with multiple imputation.

RESULTS

Compared with screen-detected BC, interval BC had higher odds of late-stage (OR = 3.50, 2.9-4.3), high-grade (OR = 2.36, 1.9-2.9) and triple-negative cancers (OR = 2.55, 1.9-3.5). Compared with other symptom-detected BC, interval BC had lower odds of late stage (OR = 0.75, 0.6-0.9), but higher odds of triple-negative cancers (OR = 1.68, 1.2-2.3). Among women who had a negative mammogram (n = 2,145), 69.8% were diagnosed at their next mammogram, while 30.2% were diagnosed with an interval cancer. Those with an interval cancer were more likely to have healthy weight (OR = 1.37, 1.1-1.7), received hormone replacement therapy (2-10 years: OR = 1.33, 1.0-1.7; > 10 years: OR = 1.55, 1.1-2.2), conducted monthly breast self-examinations (BSE) (OR = 1.66, 1.2-2.3) and had previous mammogram in a public facility (OR = 1.52, 1.2-2.0).

CONCLUSION

These results highlight the benefits of screening even among those with an interval cancer. Women-conducted BSE were more likely to have interval BC which may reflect their increased ability to notice symptoms between screening intervals.

Clusters of high-risk, low-risk, and temporal trends of breast and cervical cancer-related mortality in São Paulo, Brazil, during 2000-2016

PURPOSE

Studying breast and cervical cancers in space and time and verifying divergences of different territorially established socioeconomic profiles.

METHODS

Ecological study using spatial scanning (with socioeconomic characterization), space-time, and spatial variation of temporal trends, in order to identify significant clusters of high- and low-risk or temporal trends, of deaths from breast cancer and cervical cancer, in the city of São Paulo, Brazil, during 2000-2016.

RESULTS

High-risk spatial clusters were identified in the central areas, and low-risk clusters were identified in the peripheral areas, which were associated with better and worse socioeconomic conditions, respectively. As for cervical cancer, the pattern was the opposite. High-risk space-time clusters occurred in the early years of the study, whereas low-risk clusters occurred in the most recent years. For breast cancer, the central areas showed a temporal trend of decreasing mortality and the peripheral areas showed an increasing trend. While for cervical cancer, in general, the temporal trend was for the identified clusters to fall.

CONCLUSIONS

It is expected that this study will provide insights for the formulation of public policies to implement prevention and control measures, in order to reduce mortality and inequalities related to breast and cervical cancers.

Global Epidemiological Patterns in the Burden of Main Non-Communicable Diseases, 1990-2019: Relationships With Socio-Demographic Index

Objectives: This study aimed to analyze spatio-temporal patterns of the global burden caused by main NCDs along the socio-economic development. Methods: We extracted relevant data from GBD 2019. The estimated annual percentage changes, quantile regression and limited cubic splines were adopted to estimate temporal trends and relationships with socio-demographic index. Results: NCDs accounted for 74.36% of global all-cause deaths in 2019. The main NCDs diseases were estimated for cardiovascular diseases, neoplasms, and chronic respiratory diseases, with deaths of 18.56 (17.08-19.72) million, 10.08 (9.41-10.66) million and 3.97 (3.58-4.30) million, respectively. The death burden of three diseases gradually decreased globally over time. Regional and sex variations existed worldwide. Besides, the death burden of CVD showed the inverted U-shaped associations with SDI, while neoplasms were positively correlated with SDI, and CRD showed the negative association. Conclusion: NCDs remain a crucial public health issue worldwide, though several favorable trends of CVD, neoplasms and CRD were observed. Regional and sex disparities still existed. Public health managers should execute more targeted programs to lessen NCDs burden, predominantly among lower SDI countries.

Mortality trends of breast and cervical cancer in Passo Fundo, Rio Grande do Sul: an analysis by age and schooling, 1999-2019

OBJECTIVE

to analyze the temporal trend of mortality due to malignant neoplasms of the breast and cervix from 1999 to 2019 in Passo Fundo, Rio Grande do Sul, Brazil.

METHODS

this was a time-series study based on data from the Mortality Information System; standardized rates were calculated according to age and schooling, and the temporal trend was assessed using Prais-Winsten regression.

RESULTS

the overall mortality coefficients for cervical cancer (β = -0.03; 95%CI -0.08;0.02) and for breast cancer (β = -0.006; 95%CI -0.02;0.01) were stable over the time series; in both types of neoplasms, a rising trend was identified in women with up to 7 years of schooling; on the other hand, a stationary trend was found in the majority of the age strata analyzed.

CONCLUSION

older women and those with low levels of schooling had the worst prognosis.

Trends in Socioeconomic Inequalities in Breast Cancer Incidence Among Women in Canada

INTRODUCTION

Breast cancer is the most common cancer among females in Canada. This study examines trends in socioeconomic inequalities in the incidence of breast cancer in Canada over time from 1992 to 2010.

METHODS

A census division level dataset was constructed using the Canadian Cancer Registry, Canadian Census of the Population and National Household Survey. A summary measure of the Concentration index (C), which captures inequality across socioeconomic groups, was used to measure income and education inequalities in breast cancer incidence over the 19-year period.

RESULTS

The crude breast cancer incidence increased in Canada between 1992 and 2010. Age-standardized C values indicated no income or education inequalities in breast cancer incidence in the years from 1992 to 2004. However, the incidence was significantly concentrated among females in high income and highly educated neighbourhoods almost half the time in the 6 most recent years (2005-2010). The trend analysis indicated an increase in breast cancer incidence among females living in high income and highly educated neighbourhoods.

CONCLUSION

Breast cancer incidence in Canada was associated with increased socioeconomic status in some more recent years. Our study findings provide previously unavailable empirical evidence to inform discussions on socioeconomic inequalities in breast incidence.

Breast Cancer and Spirituality Among Women in Poland: A Case-Control Study

In this case-control study, we assessed differences in daily spiritual experiences between patients with breast cancer diagnoses and healthy controls in relation to other breast cancer risk factors. The participants were 201 newly diagnosed Polish patients with breast cancer (58 ± 6 years) and 201 age-matched healthy controls. Spiritual experiences were assessed using the Daily Spiritual Experiences Scale (DSES). Adjusted odds ratios (OR) and 95% confidence intervals (CI) of the DSES score for breast cancer diagnosis were calculated with logistic regression. The DSES score was significantly higher in the healthy controls than in the cases. After controlling for alcohol use, education, BMI, and rural residence, higher spirituality was associated with a lower risk of breast cancer (OR 0.98, 95% CI 0.97-1.00). Two DSES item scores differed significantly between cases and controls, being lower in breast cancer cases: "I am spiritually touched by the beauty of creation" (p = 0.01) and "I feel selfless caring for others" (p = 0.049). After controlling for other variables (i.e., hormone replacement therapy, family history, breastfeeding, and diet quality), the DSES score was statistically non-significant (OR 0.99, 95% CI 0.97-1.006). Therefore, the original relationship DSES score and breast cancer was quite weak. Although the study found little relationship between the analyzed variables, presented differences in spirituality may differentiate the patterns of spiritual well-being among breast cancer patients; however, more data are needed from longitudinal study designs to establish causal inferences.

Disparities in Breast Cancer Mortality Rates in Israel among Urban and Rural Women

Breast cancer is a leading cause of death. There are a number of risk factors for breast cancer mortality including parity, age, ethnicity, genetic history, and place of residence. This study examined the disparities in breast cancer-related mortality rates among women from urban areas compared to rural areas in Israel. This was a retrospective, follow-up study on mortality from breast cancer among 894,608 Israeli women born between the years of 1940 and 1960. Data was collected from the Israeli Central Bureau of Statistics, the Population Authority, the Education Ministry, and the Health Ministry. Over 80% of women lived in urban areas. A higher incidence of mortality from breast cancer in Israel was found among urban women compared to rural women (1047.8/100,000 compared to 837/100,000, respectively). Even after adjusting for sociodemographic variables, higher mortality rates were found among women from urban areas in Israel compared to women from rural areas in Israel. It is believed that environmental factors can partially explain the geographic variation of breast cancer incidence, and that breast cancer incidence is likely a complex interaction between genetic, environmental, and health factors.

Educational inequalities and premature mortality: the Cuba Prospective Study

BACKGROUND

Although socioeconomic status is a major determinant of premature mortality in many populations, the impact of social inequalities on premature mortality in Cuba, a country with universal education and health care, remains unclear. We aimed to assess the association between educational level and premature adult mortality in Cuba.

METHODS

The Cuba Prospective Study (a cohort study) enrolled 146 556 adults aged 30 years and older from the general population in five provinces from Jan 1, 1996, to Nov 24, 2002. Participants were followed up until Jan 1, 2017, for cause-specific mortality. Deaths were identified through linkage to the Cuban Public Health Ministry's national mortality records. Cox regression models yielded rate ratios (RRs) for the effect of educational level (a commonly used measure for social status) on mortality at ages 35-74 years, with assessment for the mediating effects of smoking, alcohol consumption, and BMI.

FINDINGS

A total of 127 273 participants aged 35-74 years were included in the analyses. There was a strong inverse association between educational level and premature mortality. Compared with a university education, men who did not complete primary education had an approximately 60% higher risk of premature mortality (RR 1·55, 95% CI 1·40-1·72), while the risk was approximately doubled in women (1·96, 1·81-2·13). Overall, 28% of premature deaths could be attributed to lower education levels. Excess mortality in women was primarily due to vascular disease, while vascular disease and cancer were equally important in men. 31% of the association with education in men and 18% in women could be explained by common modifiable risk factors, with smoking having the largest effect.

INTERPRETATION

This study highlights the value of understanding the determinants of health inequalities in different populations. Although many major determinants lie outside the health system in Cuba, this study has identified the diseases and risk factors that require targeted public health interventions, particularly smoking.

FUNDING

UK Medical Research Council, British Heart Foundation, Cancer Research UK, CDC Foundation (with support from Amgen).

Adherence to adjuvant endocrine therapy among White British and ethnic minority breast cancer survivors in the United Kingdom

OBJECTIVE

Around half of women do not take adjuvant endocrine therapy (AET) as prescribed. Research suggests that adherence rates vary across ethnic groups. This study compared AET adherences rates in White British women and women from minority ethnic groups in the United Kingdom.

METHODS

This is an observational study with 2001 breast cancer survivors recruited from outpatient clinics. Eligible women were diagnosed with primary breast cancer and prescribed AET within the last 3 years. Adherence was measured using the Medication Adherence Rating Scale. Eligible women were asked to complete a questionnaire pack that collected sociodemographic data such as age, relationship status and ethnicity. Independent samples t tests and χ² tests were used to compare White British women and women from minority ethnic groups on self-reported adherence to AET.

RESULTS

Of White British women, 27.8% were classed as non-adherent, compared to 44.4% of women from minority ethnic groups. A logistic regression controlling for relevant demographics indicated that women from minority ethnic groups had a significantly higher risk of non-adherence than women who were White British (odds ratio = 1.50, p = 0.03) CONCLUSION: Rates of non-adherence to AET are higher in women from minority ethnic groups, which may contribute towards racial disparities in breast cancer outcomes. Research with larger and more diverse samples is needed to explore this further and to investigate the psychosocial factors driving differences in adherence.

Socioeconomic inequalities in breast cancer survival in Reunion Island: The contribution of stage at diagnosis as a mediator

INTRODUCTION

Although breast cancer survival has improved in France, it appears that women living in deprived areas are more likely to die from breast cancer. However, no study has yet examined socioeconomic inequalities in breast cancer survival in La Réunion. Our objective was to examine whether socioeconomic inequalities in breast cancer survival exist in Reunion Island and whether stage at diagnosis could partly explain these differences.

METHODS

A population-based cohort study of all women on Reunion Island with primary breast cancer diagnosed between 2008 and 2016 was conducted. Each woman was assigned a deprivation index based on her area of residence at diagnosis. Net survival by deprivation group and stage at diagnosis was estimated by the non parametric Pohar Perme method. The role of stage (indirect effect) was assessed using a mediation analysis extended to the relative survival framework.

RESULTS

At five years, net survival was significantly lower in women living in the most deprived areas than in women living in the least deprived areas (81 % (95 % CI 77-86) and 91 % (95 % CI 89-94), respectively, p < 0.0001), and mediation analysis showed that the contribution of stage at diagnosis to these survival differences was 43 %.

DISCUSSION

Our result shows that although measures to promote earlier diagnosis are important, they would only reduce socioeconomic inequalities in breast cancer survival by 43 %. To further investigate these inequalities, future research should explore the role of unmeasured mediators, such as comorbidities and treatment received, as well as the impact of specific interventions that might address the differences in mediator distribution.

Socio-economic deprivation and cancer incidence in England: Quantifying the role of smoking

BACKGROUND

More deprived populations typically experience higher cancer incidence rates and smoking prevalence compared to less deprived populations. We calculated the proportion of cancer cases attributable to smoking by socio-economic deprivation in England and estimated the impact smoking has on the deprivation gap for cancer incidence.

METHODS

Data for cancer incidence (2013-2017), smoking prevalence (2003-2007) and population estimates (2013-2017) were split by sex, age-group and deprivation quintile. Relative risk estimates from meta-analyses were used to estimate the population attributable fraction (PAF) for 15 cancer types associated with smoking. The deprivation gap was calculated using age-specific incidence rates by deprivation quintile.

RESULTS

Smoking-related cancer PAFs in England are 2.2 times larger in the most deprived quintile compared to the least deprived quintile (from 9.7% to 21.1%). If everyone had the same smoking prevalence as the least deprived quintile, 20% of the deprivation gap in cancer incidence could have been prevented. If nobody smoked, 61% of the deprivation gap could have been prevented.

CONCLUSIONS

The majority of the deprivation gap in cancer incidence could have been prevented in England between 2013-2017 if nobody had smoked. Policy makers should ensure that tobacco control policies reduce overall smoking prevalence by tackling smoking inequalities.

Evolution of socioeconomic inequalities in cancer incidence between 2006 and 2016 in France: a population-based study

OBJECTIVE

The existence of socioeconomic inequalities in cancer incidence is now well established and their reduction is a priority in many countries. This study aimed to measure the evolution of socioeconomic inequalities in the incidence of the most common cancers in France, over an 11-year period.

METHODS

The study focused on 19 cancer entities (16 solid tumors and 3 hematological malignancies). Data are obtained from the French Network of Cancer Registries, representing 604 205 cancer cases. Each patient address was geolocalized and assigned to an IRIS, the smallest geographic unit in France. The French version of the European Deprivation Index was used to measure the level of deprivation in each IRIS. A generalized linear mixed model was used to account for the longitudinal nature of the data and to assess the evolution of socioeconomic inequalities.

RESULTS

A significant evolution of the social gradient of incidence over time was highlighted for five cancer entities and all entities combined. For lung cancer for both sexes and bladder cancer in men, more frequent in deprived areas, the social gradient in incidence tended to decrease over time. For breast cancer in women and lymphocytic leukemia in men, more frequent in affluent areas, the gap continues to widen.

CONCLUSION

Cancer entities with large disparities continued to present social inequalities in incidence without exacerbation with time. The few temporal evolutions observed do not show a worsening of the social gradient of incidence to the disadvantage of the most deprived areas, but rather an increase in incidence that is greater in the most affluent areas.

Breast Cancer in Asia: Incidence, Mortality, Early Detection, Mammography Programs, and Risk-Based Screening Initiatives

Simple Summary

Nearly all breast cancer patients survive for more than five years when the tumor is found early and in the localized stage. Regular clinical breast examinations, mammograms, and monthly self-exams of the breasts all contribute to early detection. However, late-stage breast cancers are common in many Asian countries. Low-income countries suffer from a lack of resources for breast cancer screening. High-income countries, on the other hand, are not benefiting fully from national breast screening programs due to an underutilization of the preventive healthcare services available. Existing reviews on Asian breast cancers are heavily focused on risk factors. The question of whether we should adopt or adapt the knowledge generated from non-Asian breast cancers would benefit from an extension into screening guidelines. In addition, several Asian countries are piloting studies that move away from the age-based screening paradigm.

Abstract

Close to half (45.4%) of the 2.3 million breast cancers (BC) diagnosed in 2020 were from Asia. While the burden of breast cancer has been examined at the level of broad geographic regions, literature on more in-depth coverage of the individual countries and subregions of the Asian continent is lacking. This narrative review examines the breast cancer burden in 47 Asian countries. Breast cancer screening guidelines and risk-based screening initiatives are discussed.

Comparing spatial patterns of 11 common cancers in Mainland China

Background

A stronger spatial clustering of cancer burden indicates stronger environmental and human behavioral effects. However, which common cancers in China have stronger spatial clustering and knowledge gaps regarding the environmental and human behavioral effects have yet to be investigated. This study aimed to compare the spatial clustering degree and hotspot patterns of 11 common cancers in mainland China and discuss the potential environmental and behavioral risks underlying the patterns.

Methods

Cancer incidence data recorded at 339 registries in 2014 was obtained from the “China Cancer Registry Annual Report 2017”. We calculated the spatial clustering degree of the common cancers using the global Moran’s Index and identified the hotspot patterns using the hotspot analysis.

Results

We found that esophagus, stomach and liver cancer have a significantly higher spatial clustering degree (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$p<0.05$$\end{document}p<0.05) than others. When by sex, female esophagus, male stomach, male esophagus, male liver and female lung cancer had significantly higher spatial clustering degree (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$p<0.001$$\end{document}p<0.001). The spatial clustering degree of male liver was significantly higher than that of female liver cancer (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$p<0.001$$\end{document}p<0.001), whereas the spatial clustering degree of female lung was significantly higher than that of male lung cancer (\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$p<0.001$$\end{document}p<0.001). The high-risk areas of esophagus and stomach cancer were mainly in North China, Huai River Basin, Yangtze River Delta and Shaanxi Province. The hotspots for liver and male liver cancer were mainly in Southeast China and south Hunan. Hotspots of female lung cancer were mainly located in the Pearl River Delta, Shandong, North and Northeast China. The Yangtze River Delta and the Pearl River Delta were high-risk areas for multiple cancers.

Conclusions

The top highly clustered cancer types in mainland China included esophagus, stomach and liver cancer and, by sex, female esophagus, male stomach, male esophagus, male liver and female lung cancer. Among them, knowledge of their spatial patterns and environmental and behavioral risk factors is generally limited. Potential factors such as unhealthy diets, water pollution and climate factors have been suggested, and further investigation and validation are urgently needed, particularly for male liver cancer. This study identified the knowledge gap in understanding the spatial pattern of cancer burdens in China and offered insights into targeted cancer monitoring and control.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-022-13926-y.

Occupational Factors and Socioeconomic Differences in Breast Cancer Risk and Stage at Diagnosis in Swiss Working Women

Socioeconomic differences in breast cancer (BC) incidence are driven by differences in lifestyle, healthcare use and occupational exposure. Women of high socioeconomic status (SES) have a higher risk of BC, which is diagnosed at an earlier stage, than in low SES women. As the respective effects of occupation and SES remain unclear, we examined the relationships between occupation-related variables and BC incidence and stage when considering SES. Female residents of western Switzerland aged 18−65 years in the 1990 or 2000 census, with known occupation, were linked with records of five cancer registries to identify all primary invasive BC diagnosed between 1990 and 2014 in this region. Standardized incidence ratios (SIRs) were computed by occupation using general female population incidence rates, with correction for multiple comparisons. Associations between occupation factors and BC incidence and stage at diagnosis were analysed by negative binomial and multinomial logistic regression models, respectively. The cohort included 381,873 women-years and 8818 malignant BC, with a mean follow-up of 14.7 years. Compared with reference, three occupational groups predominantly associated with a high socioprofessional status had SIRs > 1: legal professionals (SIR = 1.68, 95%CI: 1.27−2.23), social science workers (SIR = 1.29; 95%CI: 1.12−1.49) and some office workers (SIR = 1.14; 95%CI: 1.09−1.20). Conversely, building caretakers and cleaners had a reduced incidence of BC (SIR = 0.69, 95%CI: 0.59−0.81). Gradients in BC risk with skill and socioprofessional levels persisted when accounting for SES. A higher incidence was generally associated with a higher probability of an early-stage BC. Occupation and SES may both contribute to differences in risk and stage at diagnosis of BC.