Comorbidities and Cancer Survival: A Comparison between Indigenous and Non-Indigenous Australians (#127)
We investigated the associations between comorbidities, cancer treatment and survival in Indigenous and non-Indigenous people in Queensland.
Methods: A study of 956 Indigenous and 869 non-Indigenous people diagnosed with cancer during 1998-2004, frequency-matched on age, sex, remoteness of residence and cancer type, and treated in public hospitals. Survival after cancer diagnosis, and effect of stage, treatment, and comorbidities on survival were examined (Cox Regression).
Results: Overall Indigenous people had more advanced cancer stage (p=0.03), received less cancer treatment (p=0.001), and were more likely to have comorbidities than non-Indigenous (p<0.001). They were less likely to have a zero comorbidity score and more likely to have a score of 2+ (p<0.001). HbA1c, a measure of diabetes control, was recorded in the medical records of 40% of Indigenous and 21% of non-Indigenous patients with diabetes, with no difference in the proportion of HbA1c over 6.5%. Being Indigenous decreased the likelihood of any cancer treatment or curative chemotherapy. Among cases without comorbidity, being Indigenous decreased the likelihood of receiving any cancer treatment or curative surgery; that was also true among cases with a comorbidity score of one. Notably, Indigenous people without comorbidity and not socially disadvantaged, were still less likely to receive treatment than others. Adjusted non-cancer survival (HR=1.95, 95%CI 1.17-3.24) was lower in the Indigenous relative to non-Indigenous patients. There was no difference in cancer-specific survival between the groups (HR=1.10, 95%CI 0.96-1.27).
0>Conclusion: Indigenous Australians with cancer have more advanced stage at diagnosis, more comorbidities, and are less likely to receive treatment, factors which contribute to poorer cancer survival. Moreover, for patients with a more favourable distribution of such prognostic factors, Indigenous still patients received lesser treatment than others. Personalised cancer care, which addresses the social and overall health requirements of Indigenous patients, may improve their cancer outcomes.