Intussusception in Australia: epidemiology prior to the introduction of rotavirus vaccine

Objectives: To describe the incidence rate and clinical outcomes of intussusception in Australia in children aged <24 months prior to the use of rotavirus vaccines in Australia, and to explore associations between patient characteristics and outcomes in children with intussusception. Methods: This study used Australian national hospital discharge data on intussusception from July 2000 to June 2006 for children aged <24 months and data from the Australian Bureau of Statistics (ABS) as a proxy for population numbers to estimate incidence. Logistic regression was used to examine associations between patient characteristics (age, sex, ethnicity) and outcomes (length of hospital stay >2 days and the need for surgical intervention). Results: The overall incidence rate of intussusception was 5.4 per 10,000 child-years in children under 24 months (95%CI 5.17-5.70). There was a declining rate over the study period (p<0.001). Age at time of intussusception was strongly associated with length of hospital stay and surgery. Conclusions: This study provides an estimate of the pre-rotavirus vaccine incidence of intussusception across Australia, which is important for monitoring the occurrence of intussusceptions post the introduction of rotavirus vaccine.