Association Between Primary Care Use Prior to Cancer Diagnosis and Subsequent Cancer Mortality in the Veterans Affairs Health System

Abstract

ImportancePrimary care physicians (PCPs) are significant contributors of early cancer detection, yet few studies have investigated whether consistent primary care translates to improved downstream outcomes.ObjectiveTo evaluate the association of prediagnostic primary care use with metastatic disease at diagnosis and cancer-specific mortality (CSM).Design, Setting, and ParticipantsThis cohort study used databases with primary care and referral linkage from multiple Veterans’ Affairs centers from 2004 to 2017 and had a 68-month median follow-up. Analysis was completed between July 2021 and September 2022. Participants included veterans older than 39 years who had been diagnosed with 1 of 12 cancers. Inclusion criteria included known clinical staging, survival follow-up, cause of death, and receiving care at the Veterans Affairs health system (VA).ExposuresPrediagnostic PCP use, measured in the 5 years prior to diagnosis. PCP visits were binned into none (0 visits), some (1-4 visits), and annual (5 visits).Main Outcomes and MeasuresMetastatic disease at diagnosis, cancer-specific mortality (CSM) for entire cohort and stratified by tumor subtype.ResultsAmong 245 425 patients representing 12 tumor subtypes, mean age was 65.8 (9.3) years, and the cohort skewed male (97.6%), and White (76.1%), with higher levels of comorbidity (58.6% with Charlson Comorbidity Index scores ≥2). Compared with no prior visit, some PCP use was associated with 26% decreased odds of metastatic disease at diagnosis (odds ratio [OR], 0.74; 95% CI, 0.71-0.76; P < .001) and 12% reduced risk of CSM (subdistribution hazard ratio [SHR], 0.88; 95% CI, 0.86-0.89; P < .001). Annual PCP use was associated with 39% decreased odds of metastatic disease (OR, 0.61; 95% CI, 0.59-0.63; P < .001) and 21% reduced risk of CSM (SHR, 0.79; 95% CI, 0.77-0.81; P < .001). Among tumor subtypes, prostate cancer had the largest effect size for prior PCP use on metastatic disease at diagnosis (OR for annual use, 0.32; 95% CI, 0.30-0.35; P < .001) and CSM (SHRfor annual use, 0.51; 95% CI, 0.48-0.55; P < .001).Conclusions and RelevanceIn this cohort study, increased primary care use before cancer diagnosis was associated with significant decreases in metastatic disease at diagnosis and cancer-related death, with potentially the greatest difference from annual use. PCPs play a vital role in cancer prevention, and additional resources should be allocated to assist these physicians.

Understanding the role of access in Hispanic cancer screening disparities

“…Additionally, there are important disparities in screening completion, with many historically marginalized groups such as those who are racially minoritized, have a low income, or living in rural areas less likely to be up to date with recommended screening 4,7,8 . Prior studies demonstrate the importance of access to care as a predictor of timely screening, as measured by both health insurance coverage and having a primary care provider or other regular source of care 9,10 …”

“…4,7,8 Prior studies demonstrate the importance of access to care as a predictor of timely screening, as measured by both health insurance coverage and having a primary care provider or other regular source of care. 9,10 Hispanic and Latinx individuals in the United States experience structural racism across numerous determinants of well-being and health, including education, housing, employment, and health care. 11,12 This results systematic differences in care access and quality, including for cancer screening.…”

Considering context in area-level socioeconomic status, cancer treatment initiation, and survival

“…More recent studies suggest an artifact or persisting inclination: rural non-Hispanic Black individuals travel longer distances to hospitals than rural White individuals ( 26 ). Thus, the geographic location of care facilities potentially deprives historically disenfranchised populations of primary care—an enterprise favorably affecting cancer prevention and decreased mortality ( 27 ). These previous observations support Guadamuz et al’s ( 1 ) admonition to encourage federal interventions addressing persistent under-investment in healthcare systems serving historically marginalized areas.…”