Ethnic variation in the trends of new implantable cardioverter defibrillator implants in New Zealand 2005-2019 (ANZACS-QI 63)

Ethnic variation in implantable cardioverter defibrillator (ICD) implant rates have been reported internationally but have not previously been examined in New Zealand. This study examined trends in new ICD implants by ethnicity over an extended period.All patients who received a new ICD implant between 2005 and 2019 were identified using the National Minimum Dataset, which collects information on all public hospital admissions in New Zealand. Ethnicity was classified using the following standard prioritisation: Māori, Pacific, Asian and European/Other. New ICD implant rates were analysed by ethnicity and age groups.A total of 5,514 new ICDs were implanted. New ICD implant rates increased from 41.4/million in 2005 to 98.2/million in 2019, an average increase of 5.4%/year (p0.01). The highest age-standardised implant rates were among Māori, followed by Pacific, European/Other and Asian ethnicities. The largest increase was seen in Pacific people at 8.9%/year (p0.01), followed by Māori and Asian people at 4.7%/year and 4.3%/year respectively (both p0.01). In European/Other patients, ICD implant rates increased by 10.3%/year (p0.01) between 2005 to 2012, then plateaued at -0.4%/year (p=0.71) between 2012 to 2019. By 2019, the age-standardised implant rates in Māori and Pacific people were two-fold higher than European/Others.There is marked ethnic variation in ICD implant rates in New Zealand. The higher implant rates in Māori and Pacific parallel known ethnic differences in rates of underlying cardiac disease. The more rapid increase in implant rates in these ethnic groups may represent more equitable treatment over time.