Differences in mortality and incidence for major sites of cancer by education level in a Japanese population

Education level and breast cancer incidence: a meta-analysis of cohort studies

OBJECTIVE

We aimed to examine the association between education level and breast cancer incidence by a meta-analysis of cohort studies.

METHODS

Relevant studies were identified by searching PubMed, Web of Science, and Scopus databases on June 10, 2018. Reference lists from the obtained articles were also reviewed. We included cohort studies reporting relative risks with 95% CIs for the association between education level and breast cancer incidence. Either a fixed- or random-effects model was used to calculate the pooled risk estimates.

RESULTS

We identified 18 cohort studies with more than 10 million women. Compared with women with a lower education level, women with a higher education level had a significantly higher risk of developing breast cancer (pooled relative risk 1.22 [95% CI, 1.14-1.30]). The results did not differ by study area or reference group. The association remained in studies that adjusted for age at first birth and parity, but was attenuated and no longer significant when the analysis was restricted to studies that adjusted for alcohol use, to studies that adjusted for age at menopause, or to studies that adjusted for hormone therapy.

CONCLUSIONS

A higher education level may be associated with an increased risk of developing breast cancer, in which alcohol use, age at menopause, and hormone therapy may, at least partially, play a mediating role.

Long-term Trends in Prostate Cancer Incidence by Stage at Diagnosis in Japan Using the Multiple Imputation Approach, 1993-2014

BACKGROUND

This study aimed to assess long-term trends in the incidence of prostate cancer by stage at diagnosis before and after the introduction of population-based PSA screening.

METHODS

We used data from three population-based cancer registries in Japan. A total of 29,458 malignant prostate cancer cases diagnosed between 1993 and 2014 were used for the analysis. Multiple imputation with chained equations was used to impute a specific stage at diagnosis for cases with "unknown" and missing status. We estimated the age-standardized incidence rates by stage at diagnosis from 1993 to 2014, and used joinpoint linear regression models to assess changes in trend.

RESULTS

Joinpoint analyses after imputation showed that localized cancer was stable from 1993 to 2000, followed by a pronounced but insignificant increase through 2003 (from 12.1 per 100,000 in 2001 to 34.1 per 100,000 in 2003), and a significant increase thereafter [annual percentage change (APC), 4.1%]. For regional cancer, the imputed data showed that the increasing trend lasted from 1993 to 2006 (APC, 12.5%), then leveled off through 2014. For distant prostate cancer, the imputed data showed the increasing trend continued from 1993 to 2004 (APC, 2.4%), and started to marginally decline thereafter (APC, -2.2%).

CONCLUSIONS

Our study confirmed a significantly rapid increase in localized prostate cancer after the spread of PSA screening in Japan, with a marginal decrease in distant prostate cancer after 2004.

IMPACT

Evaluation of the effectiveness of PSA screening would require a comprehensive analysis of changes in mortality, survival, and treatment practices over time.

Education Level Is a Strong Prognosticator in the Subgroup Aged More Than 50 Years Regardless of the Molecular Subtype of Breast Cancer: A Study Based on the Nationwide Korean Breast Cancer Registry Database

Purpose

This study investigated the role of the education level (EL) as a prognostic factor for breast cancer and analyzed the relationship between the EL and various confounding factors.

Materials and Methods

The data for 64,129 primary breast cancer patients from the Korean Breast Cancer Registry were analyzed. The EL was classified into two groups according to the education period; the high EL group (≥ 12 years) and low EL group (< 12 years). Survival analyses were performed with respect to the overall survival between the two groups.

Results

A high EL conferred a superior prognosis compared to a low EL in the subgroup aged > 50 years (hazard ratio, 0.626; 95% confidence interval [CI], 0.577 to 0.678) but not in the subgroup aged ≤ 50 years (hazard ratio, 0.941; 95% CI, 0.865 to 1.024). The EL was a significant independent factor in the subgroup aged > 50 years according to multivariate analyses. The high EL group showed more favorable clinicopathologic features and a higher proportion of patients in this group received lumpectomy, radiation therapy, and endocrine therapy. In the high EL group, a higher proportion of patients received chemotherapy in the subgroups with unfavorable clinicopathologic features. The EL was a significant prognosticator across all molecular subtypes of breast cancer.

Conclusion

The EL is a strong independent prognostic factor for breast cancer in the subgroup aged > 50 years regardless of the molecular subtype, but not in the subgroup aged ≤ 50 years. Favorable clinicopathologic features and active treatments can explain the main causality of the superior prognosis in the high EL group.

Initial Report for the Radiation Effects Research Foundation F1 Mail Survey

To study the full health effects of parental radiation exposure on the children of the atomic bomb survivors, the Radiation Effects Research Foundation developed a cohort of 76,814 children born to atomic bomb survivors (F1 generation) to assess cancer incidence and mortality from common adult diseases. In analyzing radiationassociated health information, it is important to be able to adjust for sociodemographic and lifestyle variations that may affect health. In order to gain this and other background information on the F1 cohort and to determine willingness to participate in a related clinical study, the F1 Mail Survey Questionnaire was designed with questions corresponding to relevant health, sociodemographic, and lifestyle indicators. Between the years 2000 and 2006, the survey was sent to a subset of the F1 Mortality Cohort. A total of 16,183 surveys were completed and returned: 10,980 surveys from Hiroshima residents and 5,203 from Nagasaki residents. The response rate was 65.6%, varying somewhat across parental exposure category, city, gender, and year of birth. Differences in health and lifestyle were noted in several variables on comparison across city and gender. No major differences in health, lifestyle, sociodemographics, or disease were seen across parental exposure categories, though statistically significant tests for heterogeneity and linear trend revealed some possible changes with dose. The data described herein provide a foundation for studies in the future.

Time trends in liver cancer mortality, incidence, and risk factors by unemployment level and race/ethnicity, United States, 1969-2011

This study examined unemployment and racial/ethnic disparities in liver cancer mortality, incidence, survival, and risk factors in the United States between 1969 and 2011. Census-based unemployment rates were linked to 1969-2009 county-level mortality and incidence data, whereas 2006-2011 National Health Interview Surveys were used to examine variations in hepatitis infection and alcohol consumption. Age-adjusted mortality rates, risk-ratios, and rate-differences were calculated by year, sex, race, and county-unemployment level. Log-linear, Poisson, and logistic regression and disparity indices were used to model trends and differentials. Although liver-cancer mortality rose markedly for all groups during 1969-2011, higher unemployment levels were associated with increased mortality and incidence rates in each time period. Both absolute and relative inequalities in liver cancer mortality according to unemployment level increased over time for both males and females and for those aged 25-64 years. Compared to the lowest-unemployment group, those aged 25-64 in the highest-unemployment group had 56 and 115 % higher liver-cancer mortality in 1969-1971 and 2005-2009, respectively. Regardless of unemployment levels, Asian/Pacific Islanders and Hispanics had the highest mortality and incidence rates. The adjusted odds of hepatitis infection and heavy drinking were 38-39 % higher among the unemployed than employed. Liver-cancer mortality and incidence have risen steadily among all racial/ethnic, sex, and socioeconomic groups. Faster increases in mortality among the highest-unemployment group have led to a widening gap in mortality over time. Disparities in mortality and incidence are consistent with similar inequalities in hepatitis infection and alcohol consumption.

Education level is associated with mortality in male patients undergoing maintenance hemodialysis

BACKGROUND

Studies of the correlation between education levels and mortality in hemodialysis (HD) patients are rare. The aim of this multi-center study was to investigate the relationship between education levels and 3-year mortality rates in HD patients.

METHODS

A total of 935 HD patients from 3 HD centers participated in this 3-year prospective observational study. Education levels were categorized as either less than senior high school and above or equal to senior high school. The causes of death and mortality rates were also analyzed for each subgroup.

RESULTS

At the end of the 3-year follow-up period, 164 patients had died. In the male group, forward stepwise Cox regression analysis revealed that age, HD duration, hypertension, creatinine level, serum albumin level ≥3.6 g/dl, anuria, Kt/Vurea, and high education level were significant predictive factors for 3-year mortality rates.

CONCLUSION

This prospective observational study demonstrated that education level was associated with mortality in men undergoing HD.

Impact of educational differences as measure of socioeconomic status on survival for breast cancer patients

Aim of the study

Breast cancer is the most frequent malignancy affecting women. Some reports suggest the influence of socioeconomic status, including education, on survival rates for cancer patients. This report analyzes the effect of patients’ education level on their survival.

Material and methods

A retrospective analysis of the group of 810 breast cancer patients treated in single center in Poland was performed. The analyzed group included women with elementary education (24%), vocational training (19%), secondary (38%) or higher education (16%). Overall, recurrence-free and metastasis free survival times were analyzed.

Results

The actuarial 5-year overall survival was 72% (median 4.7 years), 5-year local recurrence-free survival was 84%, whereas metastasis-free survival 76%. Multivariate Cox model has shown that lower education had independent significantly negative influence on local recurrence-free survival time (p = 0.024). The highest risk of recurrence was found for patients with elementary education (p = 0.009). The same was confirmed for distant metastasis-free survival (p = 0.001), with the highest risk of metastases in patients with vocational education and stage IIIB breast cancer (p < 0.001). Education level had significant impact on overall survival. The patients with higher-level education lived longer (p = 0.042).

Conclusions

Shorter recurrence-free survival time among women attaining lowest education level and longer overall survival time for women with higher education level suggest the necessity for intensified cancer awareness educational effort and screening among less-educated healthy Polish women.

Ionizing radiation and kidney cancer among Japanese atomic bomb survivors

Understanding of the role of radiation as a cause of kidney cancer remains limited. The most common types of kidney cancer are renal cell carcinoma and renal pelvis carcinoma. It has been posited that these entities differ in their degree of radiogenicity. Recent analyses of cancer incidence and mortality in the Life Span Study (LSS) of Japanese atomic bomb survivors have examined associations between ionizing radiation and renal cell carcinoma, but these analyses have not reported results for cancer of the renal pelvis and ureters. This paper reports the results of analyses of kidney cancer incidence during the period 1958-1998 among 105,427 atomic bomb survivors. Poisson regression methods were used to derive estimates of associations between radiation dose (in sievert, Sv) and cancer of the renal parenchyma (n = 167), and cancer of the renal pelvis and ureter (n = 80). Heterogeneity by cancer site was tested by joint modeling of cancer risks. Radiation dose was positively associated with cancers of the renal pelvis and ureter [excess relative rate (ERR)/Sv = 1.65; 90% confidence interval (CI): 0.37, 3.78]. The magnitude of this association was larger than the estimated association between radiation dose and cancer of the renal parenchyma (ERR/Sv = 0.27; 90% CI = -0.19, 0.98). While the association between radiation and cancer of the renal parenchyma was of greater magnitude at ages <55 years (ERR/Sv = 2.82; 90% CI = 0.45, 8.89) than at older attained ages (ERR/Sv = -0.11; 90% CI = nd, 0.53), the association between radiation and cancers of the renal pelvis and ureter varied minimally across these categories of attained age. A test of heterogeneity of type-specific risks provides modest support for the conclusion that risks vary by kidney cancer site (LRT = 2.34, 1 d.f., P = 0.13). Since some studies of radiation-exposed populations examine these sites in aggregate, results were also derived for the combined category of cancer of the renal parenchyma, renal pelvis and ureters. Overall, there was a positive association between radiation and the combined category of cancer of the renal parenchyma, renal pelvis and ureters (ERR/Sv = 0.60, 90% CI: 0.09, 1.30). Updated follow-up of the LSS cohort provides substantial additional information on the association between radiation and cancer of the renal pelvis and ureter, a site not examined in recent reports on analyses of these data. The results are suggestive of differences between the different regions of the kidney in sensitivity to the carcinogenic effects of ionizing radiation.

Socioeconomic status and changing inequalities in colorectal cancer? A review of the associations with risk, treatment and outcome

BACKGROUND

Upcoming mass screening for colorectal cancer (CRC) makes a review of recent literature on the association with socioeconomic status (SES) relevant, because of marked and contradictory associations with risk, treatment and outcome.

METHODS

The Pubmed database using the MeSH terms 'Neoplasms' or 'Colorectal Neoplasms' and 'Socioeconomic Factors' for articles added between 1995 and 1st October 2009 led to 62 articles.

RESULTS

Low SES groups exhibited a higher incidence compared with high SES groups in the US and Canada (range risk ratio (RR) 1.0-1.5), but mostly lower in Europe (RR 0.3-0.9). Treatment, survival and mortality all showed less favourable results for people with a lower socioeconomic status: Patients with a low SES received less often (neo)adjuvant therapy (RR ranging from 0.4 to 0.99), had worse survival rates (hazard ratio (HR) 1.3-1.8) and exhibited generally the highest mortality rates up to 1.6 for colon cancer in Europe and up to 3.1 for rectal cancer.

CONCLUSIONS

A quite consistent trend was observed favouring individuals with a high SES compared to those with a low SES that still remains in terms of treatment, survival and thus also mortality. We did not find evidence that the low/high SES gradients for treatment chosen and outcome are decreasing. To meet increasing inequalities in mortality from CRC in Europe for people with a low SES and to make mass screening successful, a high participation rate needs to be realised of low SES people in the soon starting screening program.

Ionizing radiation and leukemia mortality among Japanese Atomic Bomb Survivors, 1950-2000

This paper provides the first comprehensive report on mortality by type of leukemia among the Japanese atomic bomb survivors in the Life Span Study (LSS). Analyses include 310 deaths due to leukemia during the period 1950-2000 among 86,611 people in the LSS. Poisson regression methods were used to evaluate associations between estimated bone marrow dose and leukemia mortality. Attention was given to variation in the radiation dose-leukemia mortality association by time since exposure, age at exposure, city and sex. The excess relative rate per gray of acute myeloid leukemia was best described by a quadratic dose-response function that peaked approximately 10 years after exposure. Acute lymphatic leukemia and chronic myeloid leukemia mortality were best described by a linear dose-response function that did not vary with time since exposure. Adult T-cell leukemia was not associated with estimated bone marrow dose. Overall, 103 of the 310 observed leukemia deaths were estimated to be excess deaths due to radiation exposure. In the most recent decade of observation (1991-2000), the estimated attributable fraction of leukemia deaths among those survivors exposed to >0.005 Gy was 0.34, suggesting that the effect of the atomic bombings on leukemia mortality has persisted in this cohort for more than five decades.