Gastric cancer survival and affiliation to health insurance in a middle-income setting

Objective: To investigate whether health insurance affiliation and socioeconomic deprivation is associated with overall cause survival from gastric cancer in a middle-income country. Methods: All patients resident in the Bucaramanga metropolitan area (Colombia) diagnosed with gastric cancer between 2003 and 2009 (n = 1039), identified in the population-based cancer registry, were followed for vital status until 31/12/2013. Kaplan-Meier models provided crude survival estimates by health insurance regime (HIR) and social stratum (SS). Multivariate Cox-proportional hazard models adjusting HIR and SS for sex, age and tumor grade, were performed. Results: Overall 1 and 5 year survival proportions were 32.4% and 11.0%, respectively, varying from 49.3% and 15.8% for patients affiliated to the most generous HIR to 12.9% and 5.3% for unaffiliated patients, and from 41.4% and 20.7% for patients in the highest SS, versus 27.1% and 7.4% for the lowest SS. The multivariate analyses showed type of HIR as well as SS to remain independently associated with survival, with an 11% improvement in survival for each increase in SS subgroup (HR 0.89 (95% CI 0.83; 0.96), and with worse survival in the subsidized (least generous) HIR and unaffiliated patients compared to the contributory HIR (HR subsidized 1.20 (95% CI 1.00; 1.43) and HR not affiliated 2.03 (95% CI 1.48; 2.78)). Of the non-affiliated patients, 60% had died at the time of diagnosis, versus 4-14% of affiliated patients (p < 0.0005). Conclusions: Despite the 'universal' health insurance system, large socioeconomic differences in gastric cancer survival exist in Colombia. Both social stratum and access to effective diagnostic and curative care strongly influence survival. (C) 2014 Elsevier Ltd. All rights reserved.