Ethnic Differences in Response Rate and Patient‐Reported Outcomes at Baseline and 12 Months Post‐Treatment Among New Zealand Men With Prostate Cancer

Background Patient‐reported outcomes (PRO) can be influenced by patient‐ and health system‐related factors. This study examined the effect of contemporary prostate cancer (PCa) treatments (watchful waiting/active surveillance, surgery, external beam radiotherapy and androgen deprivation therapy) on PRO among Māori and non‐Māori in New Zealand (NZ). Methods A total of 13 893 men (1155 Māori; 12 828 non‐Māori) with PCa were recruited from the NZ Prostate Cancer Outcome Registry, a national registry for PCa care and PRO. The Expanded Prostate Cancer Index Composite‐26 was used as the patient‐reported outcomes measure (PROM) to assess five disease‐specific functions (urinary incontinence, urinary obstructive/irritative, bowel, sexual and hormonal function) at baseline and 12 months post‐treatment. Multivariable regression analyses were performed to assess between‐group differences and post‐treatment PRO changes with adjustments for confounders. Results The PROM response rate in Māori was 1.87 to 2.04 times lower than non‐Māori at baseline and 12 months post‐treatment. Māori reported significantly worse ( p ≤ 0.002) PRO than non‐Māori in urinary incontinence, sexual and hormonal function at baseline but not sexual function ( p = 0.9) at 12 months post‐treatment after adjustments. Both groups demonstrated a similar magnitude of PRO changes 12 months post‐treatment after adjustments, except for surgery and androgen deprivation therapy, where Māori had a significantly lesser decline in hormonal function ( p = 0.003) and sexual function ( p = 0.046) post‐treatment respectively. Conclusion Findings from this study can better inform clinicians and patients in choosing a more patient‐tailored PCa treatment in NZ. More work is needed to understand the possible causes for response rate and PRO differences at baseline and 12 months post‐treatment between Māori and non‐Māori.