Beyond the traditional prognostic indicators: the impact of primary care utilization on cancer survival

To our knowledge to date, the effect of primary care utilization on health outcomes in cancer patients has not been described. The objective of this study was to investigate the impact of primary care utilization within 6 months of cancer diagnosis on survival in patients with lung cancer.

We used electronic medical record data (1997 to 2005) to identify male veterans with incident lung cancers (N = 323). Primary care utilization was assessed in the 6 months after cancer diagnosis. Patients were observed from cancer diagnosis to death or to last date of health care utilization (ie, censoring date). Univariate and multivariate Cox proportional hazards models tested whether primary care utilization was associated with improved survival. Multivariate analyses adjusted for demographic and clinical characteristics.

During an average follow-up of 16.6 months, 259 patients died. In multivariate analysis, the risk of death was 36% (hazard ratio [HR], 0.64; 95% CI, 0.45 to 0.90), 56% (HR, 0.44; 95% CI, 0.29 to 0.65), and 57% (HR, 0.43; 05% CI, 0.29 to 0.64) lower for patients who had one, two, or at least three primary care visits, respectively, in the first 6 months after cancer diagnosis as compared with those without primary care utilization. The median survival duration (P < .0001, log-rank test) was 3.68, 7.52, 13.88, and 13.75 months for patients with no, one, two, or at least three primary care visits, respectively.

Primary care utilization in the early phase of cancer treatment has a marked effect that results in a reduced mortality risk in patients with incident lung cancer. Additional research is required to determine how and why primary care utilization is an important prognostic indicator of prolonged survival in patients with lung cancer.