Global Disparities in Healthcare Resources and Cancer Burden: A Population-based Systematic Analysis of 171 Countries in 2022

Background: Global disparities in healthcare resources impact diagnosis, treatment, and ongoing supportive care for cancer. As these resource levels can be considered modifiable factors of health inequality on a global scale, we aimed to explore their association with the global cancer burden and quantify the extent of these inequalities. Methods: Healthcare resource capacity was measured using the universal health coverage (UHC) index and current health expenditure as a percentage of gross domestic product (CHE/GDP (%)). Cancer data were sourced from the GLOBOCAN database. Variables such as age-standardized incidence rate (ASIR), age-standardized mortality rate (ASMR), and a proxy of 5-year survival [1- mortality to incidence ratio (1-M/I)] were calculated. Absolute and relative inequalities in cancer burden were assessed using the slope index of inequality (SII) and concentration index (CCI). The association between healthcare resources and cancer burden was further explored by negative binomial regression. Counterfactual simulations quantify inequalities based on healthcare resource levels. Results: Marked absolute and relative inequalities were found in the burden of most cancer types related to the UHC index and the CHE/GDP (%) gradient. Both the absolute and relative burdens of cancer were concentrated in areas with high UHC index and CHE/GDP (%) levels. A significant positive association was found between the ASIR (IRR: 1.77, 95%CI: 1.57 to 2.00) and survival (IRR: 1.60, 95%CI: 1.48 to 1.73) with the UHC index. A weaker positive association was found for CHE/GDP (%) with ASIR (IRR: 1.37, 95%CI: 1.20 to 1.56) and survival (IRR: 1.23, 95%CI: 1.13 to 1.35). No significant association was found between ASMR and either the UHC index or CHE/GDP (%). An estimated 21% of cancer deaths were associated with the potential to be prevented with survival rates matching the most advanced nations in each region, and over 31% of cancer deaths were associated with the potential to be prevented with survival rates matching the most advanced nations worldwide. Conclusions: Substantial inequalities in the cancer burden related to healthcare resources are apparent worldwide. Allocating healthcare resources at optimal levels can improve survival and reduce cancer-related deaths. These findings emphasize the need for targeted interventions and policies to address inequalities in healthcare resource allocation and ensure equitable access to cancer treatment.