Association of distance to gynecologic oncologist and survival in a rural midwestern state (414)

Abstract

Objectives: Rural ovarian cancer patients experience worse survival outcomes compared to urban patients. We hypothesized that those living farther from gynecologic oncology would have greater mortality because they may be more likely to seek care locally from less specialized providers. Our objective was to assess whether distance to gynecologic oncology providers affects mortality among ovarian cancer patients living in a largely rural midwestern state. Methods: Demographic, tumor, and treatment characteristics were extracted from the Iowa Cancer Registry for patients residing in Iowa diagnosed with malignant primary ovarian cancer from 1990-2018. County-level data from the 2018-19 Area Health Resource File included a number of primary care physicians, surgeons, OB/GYN’s, and hospital beds per 10,000 population. Rurality was categorized using 2013 Rural-Urban Continuum Codes for the patient’s county of residence at the time of diagnosis. Distance to the nearest gynecologic oncologist was calculated from the centroid of the patient’s county of residence to the centroid of the nearest county in Iowa or surrounding states containing a hospital with at least one gynecologic oncologist (n=7). Survival was assessed via Cox proportional hazards models. Results: There were 1,588 patients included, with a mean distance to gynecologic oncology of 45.8 miles and a mean survival of 31 months. Unadjusted models showed those who lived farther from gynecologic oncology had progressively significantly greater risk of death compared to those who lived 0-9 miles: 10-29 (HR: 1.07, 95% CI:1.03-1.12), 30-49 (HR: 1.15, 95% CI:1.05-1.25), 50-69 (HR: 1.23, 95% CI:1.08-1.40), 70+ (HR:1.32, 95% CI:1.11-1.57). In multivariate models that included age, marital status, stage, county-level poverty, and rate of surgeons per 10,000 population, the distance was no longer associated with a higher risk of mortality. Stage II (HR: 3.10, 95% CI: 2.13-4.50), stage III (HR: 7.09, 95% CI: 5.40-9.31), stage IV (HR: 11.59, 95% CI: 8.73-15.38) versus stage I, age 60-69 (HR: 1.47, 95% CI:1.13- 1.90), age 70-79 (HR: 2.08, 95% CI: 1.59-2.71), age 80+ (HR: 4.96, 95% CI: 3.76-6.53) versus <50, unmarried versus married (HR: 1.35, 95% CI: 1.09-1.67) were the strongest predictors for risk of death. Conclusions: Those living farthest from gynecologic oncology care had an increased risk of mortality, but this increase was diminished after controlling for patient/tumor characteristics. Further studies are needed to elucidate reasons contributing to worsened survival for rural women, which could include referral practices of local providers, rates of surgery performed by general OB/GYN’s, and other unknown factors. Objectives: Rural ovarian cancer patients experience worse survival outcomes compared to urban patients. We hypothesized that those living farther from gynecologic oncology would have greater mortality because they may be more likely to seek care locally from less specialized providers. Our objective was to assess whether distance to gynecologic oncology providers affects mortality among ovarian cancer patients living in a largely rural midwestern state. Methods: Demographic, tumor, and treatment characteristics were extracted from the Iowa Cancer Registry for patients residing in Iowa diagnosed with malignant primary ovarian cancer from 1990-2018. County-level data from the 2018-19 Area Health Resource File included a number of primary care physicians, surgeons, OB/GYN’s, and hospital beds per 10,000 population. Rurality was categorized using 2013 Rural-Urban Continuum Codes for the patient’s county of residence at the time of diagnosis. Distance to the nearest gynecologic oncologist was calculated from the centroid of the patient’s county of residence to the centroid of the nearest county in Iowa or surrounding states containing a hospital with at least one gynecologic oncologist (n=7). Survival was assessed via Cox proportional hazards models. Results: There were 1,588 patients included, with a mean distance to gynecologic oncology of 45.8 miles and a mean survival of 31 months. Unadjusted models showed those who lived farther from gynecologic oncology had progressively significantly greater risk of death compared to those who lived 0-9 miles: 10-29 (HR: 1.07, 95% CI:1.03-1.12), 30-49 (HR: 1.15, 95% CI:1.05-1.25), 50-69 (HR: 1.23, 95% CI:1.08-1.40), 70+ (HR:1.32, 95% CI:1.11-1.57). In multivariate models that included age, marital status, stage, county-level poverty, and rate of surgeons per 10,000 population, the distance was no longer associated with a higher risk of mortality. Stage II (HR: 3.10, 95% CI: 2.13-4.50), stage III (HR: 7.09, 95% CI: 5.40-9.31), stage IV (HR: 11.59, 95% CI: 8.73-15.38) versus stage I, age 60-69 (HR: 1.47, 95% CI:1.13- 1.90), age 70-79 (HR: 2.08, 95% CI: 1.59-2.71), age 80+ (HR: 4.96, 95% CI: 3.76-6.53) versus <50, unmarried versus married (HR: 1.35, 95% CI: 1.09-1.67) were the strongest predictors for risk of death. Conclusions: Those living farthest from gynecologic oncology care had an increased risk of mortality, but this increase was diminished after controlling for patient/tumor characteristics. Further studies are needed to elucidate reasons contributing to worsened survival for rural women, which could include referral practices of local providers, rates of surgery performed by general OB/GYN’s, and other unknown factors.