Household disposable income and long-term survival after pulmonary resections for lung cancer

Introduction: Socioeconomic disparities have been linked to survival differences in patients with lung cancer. Swedish healthcare is tax-funded and provides equal access to care, therefore, survival following lung cancer surgery should be unrelated to household income. The aim of this study was to investigate the association between household disposable income and survival following surgery for lung cancer in Sweden.

Methods: We conducted a nationwide population-based cohort study including all patients who underwent pulmonary resections for lung cancer in Sweden 2008-2017. Individual-level record linkages between national quality and health-data registers were performed to acquire information regarding socioeconomic status and medical history. Cox regression by quintiles of household disposable income was used to estimate the adjusted risk for all-cause mortality.

Results: We included 5500 patients and the age-adjusted and sex-adjusted incidence rate of death per 100 person-years was 15 and 9.4 in the lowest and highest income quintile, respectively (mean follow-up time 3.2 years). Deprived patients were older, had more comorbidities and were less likely to have preoperative positron emission tomography or minimally invasive surgery, compared with patients with higher income. The adjusted HR for death was 0.77 (95% CI: 0.62 to 0.96) for the highest income quintile compared with the lowest.

Conclusions: We found an association between household disposable income and survival in patients who underwent surgery for lung cancer in Sweden, despite tax-funded universal health coverage. The association remained after adjustment for differences in baseline characteristics.