Use of hospital-based health care services among children aged 1 through 9 years who were born very preterm - a population-based study

Background: Very preterm (VPT) children, with a birth weight below 1500 g or delivered before 32 weeks of gestational age, are at increased risk of poorer long-term health outcomes and higher rates of hospitalization in childhood. However, considerable variation exists in the need for in-hospital care within this population. We assessed the utilization and distribution of hospital-based care from ages 1 through 9 years for a nationwide population. Methods: This was a population-based cohort of VPT children born in the period 2001-2009. We evaluated their utilization of hospital care in 2008-2010, when aged 1-9 years old. Outcomes were the incidence of hospital admissions and outpatient visits. We used Poisson regression models with multiple imputation of missing data. Results: Children born VPT had more hospital admissions compared with the general population of children aged 1-9 years. The rates of hospital admissions and outpatient visits were strongly related to clinical characteristics of the child at birth and age at admission/outpatient visit but to only a variable and minor degree to characteristics pertaining to maternal health, the sociodemographic factors, and geographical proximity to hospital services. Conclusions: Prior to this study, hospital utilization during the period 5-9 years old has been poorly documented. We found that excess utilization of hospital resources on average declines with increasing age. We also noted substantial differences in the use of hospital care across age groups and clinical factors for VPT children. The added information from the health status of mothers, social background, and geographic measures of access was limited.