Freeman Vincent L, Naylor Keith B, Boylan Emma E, Booth Benjamin J, Pugach Oksana, Barrett Richard E, Campbell Richard T, McLafferty Sara L
Division of Epidemiology and Biostatistics, School of Public Health, University of Illinois at Chicago, Chicago, IL, USA.
University of Illinois Cancer Center, University of Illinois Hospital and Health Sciences System, Chicago, IL, USA.
Cancer Med. 2020 May;9(9):3211-3223. doi: 10.1002/cam4.2957. Epub 2020 Mar 4.
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.
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.
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).
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.
获得初级医疗服务的空间便利性与晚期及致命性乳腺癌有关，但对于其与其他可通过筛查预防的癌症（如结直肠癌）结局之间的关系，人们了解较少。这项基于人群的回顾性队列研究探讨了获得初级医疗服务提供者的空间便利性是否与结直肠癌特异性生存率相关。
通过该州癌症登记处，在伊利诺伊州库克县居住的成年人中，识别出2000年至2008年间诊断出的约26600例新发结直肠癌病例，并将其地理定位到诊断时居住的普查区。采用改进的两步浮动集水区方法，利用从美国医学协会获取的执业地点，在诊断当年测量普查区层面获得初级保健医生（PCP）服务的便利性。使用国家死亡指数确定生命状态和潜在死因。在考虑普查区层面的社会经济地位、病例人口统计学、肿瘤特征和其他因素后，采用Fine-Gray比例子分布风险模型分析普查区层面PCP服务便利性得分与结直肠癌特异性生存率之间的关联。
普查区层面获得PCP服务的便利性增加与结直肠癌死亡风险降低相关（风险比[HR]，95%置信区间[CI]）=0.87[0.79,0.96]，P = 0.008，最高五分位数与最低五分位数相比），尤其是在诊断为区域阶段肿瘤的人群中（HR，95%CI = 0.80[0.69,0.93]，P = 0.004，最高五分位数与最低五分位数相比）。
在伊利诺伊州库克县，获得初级医疗服务提供者的空间便利性是结直肠癌特异性生存率的一个预测因素。未来需要开展研究，以确定癌症治疗连续过程中的哪些领域受获得初级医疗服务的空间便利性影响最大，如筛查转诊、筛查和诊断检测的可及性、治疗转诊以及获得适当的生存相关护理。
