Mortality and hospitalisation costs of rheumatic fever and rheumatic heart disease in New Zealand

Aims: To estimate the annual mortality and the cost of hospital admissions for acute rheumatic fever (ARF) and rheumatic heart disease (RHD) for New Zealand residents. Methods: Hospital admissions in 2000–2009 with a principal diagnosis of ARF or RHD (ICD9_AM 390‐398; ICD10‐AM I00‐I099) and deaths in 2000–2007 with RHD as the underlying cause were obtained from routine statistics. The cost of each admission was estimated by multiplying its diagnosis‐related group (DRG) cost weight by the national price for financial year 2009/2010. Results: There were on average 159 RHD deaths each year with a mean annual mortality rate of 4.4 per 100 000 (95% confidence limit 4.2, 4.7). Age‐adjusted mortality was five‐ to 10‐fold higher for Māori and Pacific peoples than for non‐Māori/Pacific. The mean age at RHD death (male/female) was 56.4/58.4 for Māori, 50.9/59.8 for Pacific and 78.2/80.6 for non‐Māori, non‐Pacific men and women. The average annual DRG‐based cost of hospital admissions in 2000–2009 for ARF and RHD across all age groups was $12.0 million (95% confidence limit $11.1 million, $12.8 million). Heart valve surgery accounted for 28% of admissions and 71% of the cost. For children 5–14 years of age, valve surgery accounted for 7% of admissions and 27% of the cost. Two‐thirds of the cost occurs after the age of 30. Conclusions: ARF and RHD comprise a burden of mortality and hospital cost concentrated largely in middle age. Māori and Pacific RHD mortality rates are substantially higher than those of non‐Māori/Pacific.