Lauren E Wilson

Health care access domains and treatment as mediators of ovarian cancer racial disparities in survival: a structural equation modeling analysis in SEER-Medicare

Abstract Racial differences in health care access (HCA) may contribute to disparities in ovarian cancer (OC) survival. We used structural equation models (SEMs) to examine associations between race and HCA domains (affordability, availability, accessibility) in relation to overall and OC-specific mortality. Non-Hispanic (NH)–Black and non-Black (Hispanic, NH-White) women diagnosed with OC in 2008-2015 were identified from Surveillance, Epidemiology, and End Results–Medicare. Cox proportional hazards regression was used to conduct mediation analysis for associations between race and HCA domains with overall and OC-specific mortality. SEM models adjusting for demographic and clinical covariates were used to estimate hazard ratios (HRs) and 95% CIs. A total of 4629 eligible patients with OC were identified, including 255 (5.5%) patients who were NH-Black. In SEM adjusting for demographic, clinical, and HCA latent variables, there was a total effect of NH-Black race on overall (HR, 1.11, 95% CI, 1.03-1.19) and OC-specific mortality (HR, 1.16; 95% CI, 1.08, 1.24), which was primarily driven by a direct effect. There was a modest indirect association between NH-Black race and mortality through decreased treatment receipt, though not through HCA. There is a need for studies investigating additional social and biological mechanisms that contribute to worse cancer survival among NH-Black patients. This article is part of a Special Collection on Gynecological Cancer.

Ovarian Cancer Epidemiology, Healthcare Access and Disparities (ORCHiD): methodology for a population-based study of black, Hispanic and white patients with ovarian cancer

IntroductionLess than 40% of patients with ovarian cancer (OC) in the USA receive stage-appropriate guideline-adherent surgery and chemotherapy. Black patients with cancer report greater depression, pain and fatigue than white patients. Lack of access to healthcare likely contributes to low treatment rates and racial differences in outcomes. The Ovarian Cancer Epidemiology, Healthcare Access and Disparities study aims to characterise healthcare access (HCA) across five specific dimensions—Availability, Affordability, Accessibility, Accommodation and Acceptability—among black, Hispanic and white patients with OC, evaluate the impact of HCA on quality of treatment, supportive care and survival, and explore biological mechanisms that may contribute to OC disparities.Methods and analysisWe will use the Surveillance Epidemiology and Ends Results dataset linked with Medicare claims data from 9744 patients with OC ages 65 years and older. We will recruit 1641 patients with OC (413 black, 299 Hispanic and 929 white) from cancer registries in nine US states. We will examine HCA dimensions in relation to three main outcomes: (1) receipt of quality, guideline adherent initial treatment and supportive care, (2) quality of life based on patient-reported outcomes and (3) survival. We will obtain saliva and vaginal microbiome samples to examine prognostic biomarkers. We will use hierarchical regression models to estimate the impact of HCA dimensions across patient, neighbourhood, provider and hospital levels, with random effects to account for clustering. Multilevel structural equation models will estimate the total, direct and indirect effects of race on treatment mediated through HCA dimensions.Ethics and disseminationResult dissemination will occur through presentations at national meetings and in collaboration with collaborators, community partners and colleagues across othercancer centres. We will disclose findings to key stakeholders, including scientists, providers and community members. This study has been approved by the Duke Institutional Review Board (Pro00101872). Safety considerations include protection of patient privacy. All disseminated data will be deidentified and summarised.

Associations of Healthcare Affordability, Availability, and Accessibility with Quality Treatment Metrics in Patients with Ovarian Cancer

Abstract Background: Differential access to quality care is associated with racial disparities in ovarian cancer survival. Few studies have examined the association of multiple healthcare access (HCA) dimensions with racial disparities in quality treatment metrics, that is, primary debulking surgery performed by a gynecologic oncologist and initiation of guideline-recommended systemic therapy. Methods: We analyzed data for patients with ovarian cancer diagnosed from 2008 to 2015 in the Surveillance, Epidemiology, and End Results–Medicare database. We defined HCA dimensions as affordability, availability, and accessibility. Modified Poisson regressions with sandwich error estimation were used to estimate the relative risk (RR) for quality treatment. Results: The study cohort was 7% NH-Black, 6% Hispanic, and 87% NH-White. Overall, 29% of patients received surgery and 68% initiated systemic therapy. After adjusting for clinical variables, NH-Black patients were less likely to receive surgery [RR, 0.83; 95% confidence interval (CI), 0.70–0.98]; the observed association was attenuated after adjusting for healthcare affordability, accessibility, and availability (RR, 0.91; 95% CI, 0.77–1.08). Dual enrollment in Medicaid and Medicare compared with Medicare only was associated with lower likelihood of receiving surgery (RR, 0.86; 95% CI, 0.76–0.97) and systemic therapy (RR, 0.94; 95% CI, 0.92–0.97). Receiving treatment at a facility in the highest quartile of ovarian cancer surgical volume was associated with higher likelihood of surgery (RR, 1.12; 95% CI, 1.04–1.21). Conclusions: Racial differences were observed in ovarian cancer treatment quality and were partly explained by multiple HCA dimensions. Impact: Strategies to mitigate racial disparities in ovarian cancer treatment quality must focus on multiple HCA dimensions. Additional dimensions, acceptability and accommodation, may also be key to addressing disparities.

Health Care Access Dimensions and Racial Disparities in End-of-Life Care Quality among Patients with Ovarian Cancer

Abstract This study investigated the association between health care access (HCA) dimensions and racial disparities in end-of-life (EOL) care quality among non-Hispanic Black (NHB), non-Hispanic White (NHW), and Hispanic patients with ovarian cancer. This retrospective cohort study used the Surveillance, Epidemiology, and End Results–linked Medicare data for women diagnosed with ovarian cancer from 2008 to 2015, ages 65 years and older. Health care affordability, accessibility, and availability measures were assessed at the census tract or regional levels, and associations between these measures and quality of EOL care were examined using multivariable-adjusted regression models, as appropriate. The final sample included 4,646 women [mean age (SD), 77.5 (7.0) years]; 87.4% NHW, 6.9% NHB, and 5.7% Hispanic. In the multivariable-adjusted models, affordability was associated with a decreased risk of intensive care unit stay [adjusted relative risk (aRR) 0.90, 95% confidence interval (CI): 0.83–0.98] and in-hospital death (aRR 0.91, 95% CI: 0.84–0.98). After adjustment for HCA dimensions, NHB patients had lower-quality EOL care compared with NHW patients, defined as: increased risk of hospitalization in the last 30 days of life (aRR 1.16, 95% CI: 1.03–1.30), no hospice care (aRR 1.23, 95% CI: 1.04–1.44), in-hospital death (aRR 1.27, 95% CI: 1.03–1.57), and higher counts of poor-quality EOL care outcomes (count ratio:1.19, 95% CI: 1.04–1.36). HCA dimensions were strong predictors of EOL care quality; however, racial disparities persisted, suggesting that additional drivers of these disparities remain to be identified. Significance: Among patients with ovarian cancer, Black patients had lower-quality EOL care, even after adjusting for three structural barriers to HCA, namely affordability, availability, and accessibility. This suggests an important need to investigate the roles of yet unexplored barriers to HCA such as accommodation and acceptability, as drivers of poor-quality EOL care among Black patients with ovarian cancer.