Differences in survival among rural and urban lung cancer patients in Florida, 1996-2007

Introduction: Evidence on whether lung cancer survival is affected by place of residence is mixed. Using a large dataset with clinical and sociodemographic data, we explored the differences in survival between rural and urban patients in the state of Florida.

Methods: Florida Cancer Data System Registry (1996-2007), Agency for Health Care Administration, and US Census data were linked (n=165,465). Place of residence was defined using the Rural-Urban Community Area Codes. Descriptive demographic statistics for rural vs. urban cancer patients, and Cox regression models exploring the association of place of residence with survival were performed.

Results: Overall, 93% of patients were urban and 7% rural residents. The distribution of ethnicity differed between urban (non-Hispanic 93.6%, Hispanic 6.4%) and rural (non-Hispanic 98.4%, Hispanic 1.6%); as did the distribution of socioeconomic status (SES) – from lowest to highest quartiles in urban (12.4, 30.3, 38.9, 18.4%) and rural (19.7, 61.9, 17.2, 1.2%) areas. More rural (75.4%) than urban (63.5%) patients were seen at low-volume hospitals and more had small cell lung cancer (13.4 vs. 12.4% respectively). Median survival time was shorter (6.9 months) in rural than urban (8.2 months) patients. In the multivariate model, adjusting for comorbidities, sociodemographic, clinical, and treatment characteristics, there was no difference in survival between rural and urban residents (Hazard ratio:1.00; 95%CI: 0.94-1.06]).

Conclusion: Unadjusted median survival is shorter in rural vs. urban lung cancer patients. However, this survival difference appears to be due to differences in case-mix and sociodemographic status.