Spatial access to primary care providers and colorectal cancer‐specific survival in Cook County, Illinois

• Published in: Cancer medicine (Malden, MA) MA), 2020-05, Vol.9 (9), p.3211-3223
• Main Authors: Freeman, Vincent L., Naylor, Keith B., Boylan, Emma E., Booth, Benjamin J., Pugach, Oksana, Barrett, Richard E., Campbell, Richard T., McLafferty, Sara L.
• Format: Article
• Language: English
• Subjects: Adolescent; Adult; Aged; Breast cancer; Cancer Prevention; Catchment areas; Census of Population; Child; Child, Preschool; Colorectal cancer; Colorectal carcinoma; Colorectal Neoplasms - epidemiology; Colorectal Neoplasms - mortality; Colorectal Neoplasms - pathology; Death; Demography; Diagnosis; Female; Follow-Up Studies; Health care; Health Personnel - statistics & numerical data; Health Services Accessibility - trends; Humans; Illinois - epidemiology; Male; Middle Aged; Original Research; Physicians; Population studies; Primary care; Primary Health Care - statistics & numerical data; Prognosis; residence characteristics; Socioeconomic Factors; Spatial Analysis; Survival; Survival Rate; Tumors; Young Adult
• ISSN: 2045-7634; 2045-7634
• DOI: 10.1002/cam4.2957

Background Spatial access to primary care has been associated with late‐stage and fatal breast cancer, but less is known about its relation to outcomes of other screening‐preventable cancers such as colorectal cancer. This population‐based retrospective cohort study examined whether spatial access to primary care providers associates with colorectal cancer‐specific survival. Methods Approximately 26 600 incident colorectal cancers diagnosed between 2000 and 2008 in adults residing in Cook County, Illinois were identified through the state cancer registry and georeferenced to the census tract of residence at diagnosis. An enhanced two‐step floating catchment area method measured tract‐level access to primary care physicians (PCPs) in the year of diagnosis using practice locations obtained from the American Medical Association. Vital status and underlying cause of death were determined using the National Death Index. Fine‐Gray proportional subdistribution hazard models analyzed the association between tract‐level PCP access scores and colorectal cancer‐specific survival after accounting for tract‐level socioeconomic status, case demographics, tumor characteristics, and other factors. Results Increased tract‐level access to PCPs was associated with a lower risk of death from colorectal cancer (hazard ratio [HR], 95% confidence interval [CI]) = 0.87 [0.79, 0.96], P = .008, highest vs lowest quintile), especially among persons diagnosed with regional‐stage tumors (HR, 95% CI = 0.80 [0.69, 0.93], P = .004, highest vs lowest quintile). Conclusions Spatial access to primary care providers is a predictor of colorectal cancer‐specific survival in Cook County, Illinois. Future research is needed to determine which areas within the cancer care continuum are most affected by spatial accessibility to primary care such as referral for screening, accessibility of screening and diagnostic testing, referral for treatment, and access to appropriate survivorship‐related care. In this population‐based retrospective cohort study of approximately 26 600 incident colorectal cancers diagnosed in Cook County, IL between 2000 and 2008, spatial access to primary care was associated with colorectal cancer‐specific survival independent of neighborhood socioeconomic status, tumor stage, and other factors. To elucidate the underlying mechanisms, future research is needed to determine which areas within the cancer care continuum are most affected by spatial accessibility to primary care.