Lung cancer affects many Ontarians, and there are large differences in the cancer rates across the province. We evaluated small area disparities in incidence and 5-year relative survival over time to help inform cancer control.
This study explored how socioeconomic status, urban-rural-remoteness, and, for incidence, risk factor prevalence can influence inequalities the burden of lung cancer among Ontarians, 1999-2018. Full Bayesian space-time hierarchical models with conditionally autoregressive smoothing across space and time dimensions were used. Poisson linear mixed models were employed to estimate incidence rate ratios. Excess mortality proportional odds models with restricted cubic splines for the baseline hazard functions were employed for relative survival.
Overall, lung cancer incidence rates declined, and 5-year survival improved in Ontario. Poorer outcomes were associated with lower socioeconomic status and residing outside large urban areas. Residual disparities were evident and may be related to other factors such as access to primary care.