Polynesians with multiple myeloma living in New Zealand are diagnosed at a younger age and have poorer outcomes compared to non-Polynesians a study has found.
Dr Hilary Blacklock, a haematologist at Middlemore Hospital, Auckland told Blood 2019 delegates that it was well established that Pacific Islanders in New Zealand had poorer health and outcomes compared to other ethnicities.
“There is an enormous effort in New Zealand to try and raise the standard of healthcare for Polynesians but I think it is going to take a long time to improve outcomes,” noted Dr Blacklock who is also an Associate Professor in the Department of Molecular Medicine at the School of Medicine and Medical Director of the NZ bone marrow donor registry.
To explore whether the health inequalities seen in Pacific Islanders extended to multiple myeloma, the research team, which included Joy Ho, Peter Mollee, Hang Quach and Andrew Spencer, looked at data from the Myeloma Related Disease registry which included 442 New Zealand patients with multiple myeloma.
Data was available for 90 Polynesians who were compared with a control group of 268 non-Polynesians of mostly European Heritage.
According to Dr Blacklock, the most interesting and striking finding of the study was that the Polynesian cohort were diagnosed at a significantly younger age compared to non-Polynesians.
“Their median age at diagnosis was 63 compared to 70 for the non-Polynesian population…we need to look at the reasons behind this,” she told the conference.
Trial results also showed that the Polynesian cohort had poorer outcomes. After adjustment for age and not receiving chemotherapy the hazard ratio for overall survival in the Polynesian population was 1.94 [CI 1.24 -3.04; P<0.001] and 1.64 [CI 1.04-2.58; p=0.03] respectively.
The Polynesian cohort also tended to have a higher ECOG score and a higher incidence of renal insufficiency, higher BMI and were more likely to have diabetes.
Polynesians were also more likely to have karotype abnormalities at diagnosis (40% vs 22%), including del (13q) (10% vs 3%) and were less likely to receive anti-myeloma drug therapy (86% vs 93%, p=0.024).
“We’ve talked about are there any modifiable factors that can be changed to improve the outcomes for Polynesians… we have started to have conversations at a registry level to see what sort of investigations can have possibly at the genomic level to see why they have an increased risk of multiple myeloma,” Dr Blacklock concluded.