Rural/Regional Place of Residence Impacts Post Allogeneic Bone Marrow Transplant Overall Survival of Australian Patients with Acute Myeloid Leukaemia: An Anztct Registry Study
Authors: Khan Zulekha , Kennedy Glen A , Scott Ashleigh P , Curley Cameron , Kwan John , Melville Kate , Booth Rebecca , Bajel Ashish , Ritchie David S. , Cummins Katherine , Moore John , Bardy Peter , Shanmuganathan Naranie , Fleming Shaun , Cirone Bianca , Cooney Julian , Jackson William , Kliman David , Sipavicius Julija , Abadir Edward , Getta Bartlomiej , Irving Ian Michael , Lai Hock Choong , Wong Eric , Wilcox Leonie , Tran Steven , Hamad Nada 
Published: December 2024

Title

Rural/regional place of residence impacts post allogeneic bone marrow transplant overall survival of Australian patients with acute myeloid leukaemia: an ANZTCT Registry study

Background

Research indicates that individuals residing in rural/remote areas may experience poorer clinical outcomes in comparison to those residing in urban settings. Using data submitted to the Australia and New Zealand Transplant and Cellular Therapies Registry (ANZTCT, formerly Australasian Bone Marrow Transplant Recipient Registry), our paper examined the relationship between recipient residence location and mortality in Australian BMT patients. We looked at whether place of residence (metropolitan, regional or rural/remote) is associated with poorer overall survival (OS) in patients with Acute-Myeloid-Leukaemia-(AML) who received an allogeneic stem cell transplant (alloSCT).

Aims

To examine the relationship between-rurality-based-on a recipient's nominated residential postcode and mortality in patients with acute myeloid leukaemia who received an allogeneic bone marrow transplant (alloHCT).

Methods

Using data submitted to the ANZTCT Registry, a retrospective analysis was used to assess the outcomes of alloHCT recipients by postcode as classified in the Modified Monash Model (MMM) of remoteness. Data was obtained for the 20090-2019 period, for adult patients undergoing an alloHCT at Australian transplant centres. The primary outcomes were overall survival (OS) defined as death from any cause and non-relapse mortality (NRM) defined as death from any cause other than relapse. Association between MMM category, and other pre transplant patient criteria, on the endpoints were analysed using multivariable Cox Regression. Patient, disease, and alloHCT related characteristics, were compared according to postcode classification.

Results

Initial analyses of the 1729 patients included in the study (1201 metropolitan, 151 regional and 377 residing in remote areas) showed that patient age at alloHCT, donor type and disease response status at transplant were associated with patient OS in addition to the MMM area of residence. Cumulative incidence of NRM was not significantly different between the groups with p=0.2. However cumulative incidence of relapse death showed a difference between groups with an overall p value of 0.04. After adjusting for age, donor type and disease response status in multivariate analyses, our study showed that there was a difference in OS between areas of remoteness with HR 1.36 (CI:1.08-1.70) p=0.008 for regional patients and HR: 1.27 (CI:1.08-1.49) p=0.003 for rural/remote.

Conclusion

Our study demonstrated a statistically significant difference in OS based on nominated residential postcode for those undergoing alloHCT. This study represents the first registry based study demonstrating disparity in alloHCT outcomes of Australian patients based on their primary residence. One potential explanation for this finding could be ease of access to specialist care based at metropolitan transplant centres. Differences in social determinants of health between MMM groups could not be addressed in this retrospective analysis.