Impact of socioeconomic status on cancer incidence and stage at diagnosis: selected findings from the surveillance, epidemiology, and end results: National Longitudinal Mortality Study

Abstract

BackgroundPopulation-based cancer registry data from the Surveillance, Epidemiology, and End Results (SEER) Program at the National Cancer Institute (NCI) are mainly based on medical records and administrative information. Individual-level socioeconomic data are not routinely reported by cancer registries in the United States because they are not available in patient hospital records. The U.S. representative National Longitudinal Mortality Study (NLMS) data provide self-reported, detailed demographic and socioeconomic data from the Social and Economic Supplement to the Census Bureau's Current Population Survey (CPS). In 1999, the NCI initiated the SEER-NLMS study, linking the population-based SEER cancer registry data to NLMS data. The SEER-NLMS data provide a new unique research resource that is valuable for health disparity research on cancer burden. We describe the design, methods, and limitations of this data set. We also present findings on cancer-related health disparities according to individual-level socioeconomic status (SES) and demographic characteristics for all cancers combined and for cancers of the lung, breast, prostate, cervix, and melanoma.MethodsRecords of cancer patients diagnosed in 1973–2001 when residing 1 of 11 SEER registries were linked with 26 NLMS cohorts. The total number of SEER matched cancer patients that were also members of an NLMS cohort was 26,844. Of these 26,844 matched patients, 11,464 were included in the incidence analyses and 15,357 in the late-stage diagnosis analyses. Matched patients (used in the incidence analyses) and unmatched patients were compared by age group, sex, race, ethnicity, residence area, year of diagnosis, and cancer anatomic site. Cohort-based age-adjusted cancer incidence rates were computed. The impact of socioeconomic status on cancer incidence and stage of diagnosis was evaluated.ResultsMen and women with less than a high school education had elevated lung cancer rate ratios of 3.01 and 2.02, respectively, relative to their college educated counterparts. Those with family annual incomes less than $12,500 had incidence rates that were more than 1.7 times the lung cancer incidence rate of those with incomes $50,000 or higher. Lower income was also associated with a statistically significantly increased risk of distant-stage breast cancer among women and distant-stage prostate cancer among men.ConclusionsSocioeconomic patterns in incidence varied for specific cancers, while such patterns for stage were generally consistent across cancers, with late-stage diagnoses being associated with lower SES. These findings illustrate the potential for analyzing disparities in cancer outcomes according to a variety of individual-level socioeconomic, demographic, and health care characteristics, as well as by area measures available in the linked database.

Access to treatment and educational inequalities in cancer survival

“…This indicates that patients with a university level education tend to be less in need of specialized care at national hospitals. This is consistent with previous studies that have documented that people with higher education are more likely to be diagnosed at an earlier stage (Clegg et al 2009). The e ect of education on survival, on the other hand, decreases when disease controls are added.…”

“…Today, multimodal treatment regimens, i.e., various combinations of surgery, radiation, and chemotherapy, predominate. 9 Searches in newspaper archives indicate that doctors from the Northern health region received training in Oslo prior to the opening of the regional wards. The Cancer Registry contains detailed information about the date of diagnosis, the patient's age at diagnosis, gender, tumor location (International Classi cation of Diseases, 10th revision (ICD-10)), stage at diagnosis (local, regional, distant or unknown), residential municipality on the date of diagnosis, and the health region the patient was treated and/or examined in.…”

Impact of socioeconomic status on prostate cancer diagnosis, treatment, and prognosis

“…7,8,16 Indeed, in our study, approximately 63% of prostate cancers diagnosed among men of high SES are detected through screening compared with 48% for men of low SES. The results of the current study are consistent with previous studies reporting that men from higher social classes are more likely to be diagnosed with localized disease 8,10,13,27 and that lower SES is associated with a lower likelihood of undergoing PSA testing. 7 Although evidence that prostate cancer deaths are reduced by PSA screening is insufficient, its use may still serve as a marker of delivery of care.…”

Socioeconomic status and diagnosis, treatment, and mortality in men with prostate cancer. Nationwide population‐based study

“…In many countries, cancer outcomes are better in women and men with high compared to low socioeconomic status (SES) 1, 2. This association has also been observed in Sweden, a country with a tax‐financed national health care system aiming to provide care on equal terms to all residents 3, 4, 5…”