Seasonal variation in acute hospital admissions and emergency room presentations among children in the Australian Capital Territory

Aim: To examine seasonal variation in hospital use for five paediatric conditions of the Australian Capital Territory residents. Methods: Hospital admissions (1993-2004) and emergency room (ER) presentations (1999-2004) for asthma, croup, bronchiolitis, other respiratory conditions and diarrhoea of children aged <5 years were compared by month and season. Results: The five conditions comprised 14% of admissions and 24% of ER presentations of children aged <5 years. Bronchiolitis (both admissions and ER presentations) were the highest in the 0-1 year age group (>80%) and the other four conditions peaked at 1-2 years. Children aged 0-2 years contributed 66% of diarrhoea, 62% of croup and 44% of other respiratory admissions whereas ER presentations were higher for other respiratory conditions (57%) and lower for croup (47%). Boys showed higher rates of admissions and ER presentations for all conditions except diarrhoea. Strong seasonal associations were apparent. Incident rate ratios of admissions were significantly higher in autumn compared with summer for asthma and croup whereas bronchiolitis and other respiratory conditions admissions were the highest in winter. Diarrhoea admissions were the highest in spring. ER presentations of the five conditions also showed similar associations with season. Conclusion: Hospital admissions and ER presentations of these five conditions showed strong seasonal patterns, knowledge of which could contribute to improved resource planning (staffing) to meet expected increases in demand for services and scheduling of elective admissions. These findings could be extended to develop a model for forecasting hospital use and to explore the causes of these diseases to ameliorate seasonal effects.