Early Childhood Caries Experience Associated with Upper Respiratory Infection in US Children: Findings from a Retrospective Cohort Study.

Abstract

Both Early Childhood Caries (ECC) and Upper Respiratory Infection (URI) are infectious diseases. The oral cavity is considered a potential reservoir of respiratory pathogens due to the anatomical proximity between the oral cavity and respiratory system, which implies a potential association between ECC and URI. Hence, this study aimed to evaluate the association between ECC experience and URI incidence in preschool children. This retrospective cohort study collected data via electronic health records. The exposure was ECC before 3 years of age. The dependent variable was the incidence of URI between 4-6 years of age. To analyze the factors associated with the time-to-event of URI, we used log-rank tests and Cox regression models to compare the survival of URI between the ECC and Caries-Free (CF) groups, adjusting factors including demographic-socioeconomic characteristics and medical conditions. To analyze factors associated with the number of URI episodes, we used negative binomial regression models adjusting for factors mentioned above. A total of 497 US preschool children were included, with 117 ECC and 380 CF children. More children with ECC (58.1%) developed URI than the CF group (47.6%) during the follow-up period (4-6 years of age) (p=0.04). The ECC children were at 1.6 times higher risk to develop URI than the CF children even after accounting for other URI risk factors (Hazard Ratio 1.57 (1.13, 2.10), p=0.007). Our study suggests a potential association between ECC and URI, with an inference that early life ECC experience could be used as a predictor for developing URI in preschool age. The causal relationship between ECC and URI incidence in young children needs to be investigated through future studies.