Recurrent gastroenteritis among infants in Western Australia: a seven-year hospital-based cohort study.

Purpose: To investigate factors that affect the frequency of recurrent gastroenteritis among infants in Western Australia (WA).

Methods: A 7-year retrospective cohort study was undertaken on all infants born in 1995 who were admitted for gastroenteritis during their first year of life (n=514). Linked hospitalization records of the cohort were retrieved to derive the number of readmissions, microbiologic diagnoses, patient demographics, and co-morbidities at the index episode. A negative binomial regression model adjusting for inter-hospital variations was used to determine the prognostic factors influencing recurrent gastroenteritis.

Results: Diarrhea with no specific etiology accounted for 54.7% of the cases presented at index admission and 55.8% of the total 676 admissions for the cohort. Of the 514 infants, 119 (23%) experienced repeated episodes of gastroenteritis. The lowest proportion of recurrences was 15.4% for patients initially admitted for bacterial or viral diarrhea. Over 85% of the recurrences from either bacterial and viral diarrhea or etiology unspecified were readmitted under the same category. Aboriginality and dehydration were significantly associated with the recurrence frequency, the adjusted incidence rate ratio being 2.86 (95% CI, 1.92-4.26) and 0.66 (95% CI, 0.49-0.88), respectively. Aboriginal infants contributed to 58% of those patients in the cohort who sustained repeated episodes of gastroenteritis. The proportion of patients with the recurrent disease was also significantly higher for Aboriginals (39%) than for non-Aboriginals (15%). The effect of dehydration was evident after accounting for within hospital correlations.

Conclusions: Hospitalizations for recurrent gastroenteritis were more frequent among Aboriginal children than non-Aboriginal children in WA. Readmissions were also related to the presence of dehydration at the index episode. These findings have implications for preventive strategies to reduce the burden of gastroenteritis.