Immigrant background and hospital care because of dental caries among preschool children in Sweden: A longitudinal, register-based study in a national cohort.

Abstract: Introduction: Dental caries among preschool children is a global problem, a burden on children’s well-being, and an economic burden on healthcare systems. In Sweden, preschool children with an immigrant background have a higher prevalence of caries. Extensive treatment need and long-standing poor oral health may require dental treatment within hospital care. This study aimed to investigate whether an immigrant background among preschool children in Sweden increased the risk for hospital care because of dental caries. Methods: This was a longitudinal, register-based study using a cohort of 1 621 038 children. The children were 1-6 years old Swedish-born residents between 2001-2013. Data was retrieved from national registers like the Medical Birth Register, LISA, the Multi-Generation Register and the Patient Discharge Register. The registers were accessed via the National Board of Health and Welfare, and Statistics Sweden. The two exposure variables of interest were parents’ region of birth and duration of residence in Sweden, while the outcome was treatment within hospital care. Incidence of hospital care per 10,000 person-years was calculated using person-time data. The risk of hospital care was expressed as hazard ratios obtained by Cox regression, with 95% confidence intervals. Results: Incidence of dental treatment within hospital care was higher among children that were male, had single parents, had parents with low education, belonged to the lowest income quintile, and of Eastern European origin. Two separate regression analyses were done for region of birth, and duration of residence. In the adjusted model, Eastern European origin presented the highest risk for hospital care (HR=5.2, 95% CI=4.2-6.5), Western Europeans and NonEuropeans had almost equal risks (HR= 2.0, 95% CI=1.4-2.7 and HR=1.9, 95% CI= 1.5-2.3 respectively), and a mixed origin entailed the least risk (HR=1.4, 95% CI=1.1-1.8). ). A 0-5 years’ residence in Sweden increased the risk of hospital care (HR=1.5,95% CI=1.1-2.0) compared to more than 11 years’ residence. Conclusion: An immigrant background, and specifically Eastern European origin increased the risk of hospital care due to dental caries among preschool children in Sweden.