Variation in publicly funded bariatric surgery in New Zealand by ethnicity: Prospective cohort study of 328,739 patients

Abstract Aim To determine whether receipt of publicly funded bariatric surgery varies by ethnicity, after adjustment for comorbidities. Methods A cohort study of New Zealanders aged 30-79 years who had cardiovascular risk assessment in primary care between January 1, 2010 and June 30, 2018 was performed. Data were collated and analyzed using an encrypted unique identifier with regional and national datasets. Cox proportional hazard modeling was performed to determine the likelihood of receipt of a primary publicly funded bariatric procedure up to December 31, 2018, after adjustment for sex, age, ethnicity, locality, socioeconomic deprivation, body mass index, diabetes status, smoking status and comorbidities. Results A total of 328,739 participants (44% female, median age 54 years [interquartile range, IQR, 46-62], 54% European, 13% Māori, 13% Pacific, 20% Asian) were included in the study and followed up for a median of 5.6 years (IQR 4.1-6.9). The likelihood of receipt of bariatric surgery was lower for Māori and Pacific compared with Europeans (adjusted hazard ratio 0.82 [95% CI 0.69-0.96] and 0.24 [0.20-0.29], respectively). The likelihood of receiving bariatric surgery was also inversely related with increasing socioeconomic deprivation and rurality. Discussion Consistent with data worldwide, there is evidence of unequal access to publicly funded bariatric surgery by ethnicity, locality as well as socioeconomic deprivation among New Zealanders who were cardiovascular risk assessed in primary care.