Does dental caries lead to stunting and wasting in children?

Design This was a systematic review of the evidence on the impact of dental caries severity and prevalence on undernutrition (wasting and stunting) in children.Study selection The systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and registered with PROSPERO (registration number CRD42018091581). A database search of Medline and Embase was conducted in March 2018 with an updated search in July 2019. Participants were children aged 0-18 years from countries of different income groups. The exposure variable was dental caries reported as prevalence, incidence and/or severity, or changes in those variables. The outcome variable was undernutrition; specifically, wasting (low weight-for-height) and stunting (low height-for-age) in children.Data analysis Evidence was grouped into caries of the permanent dentition, primary dentition, early childhood caries and severe early childhood caries as a risk factor for undernutrition. A best-available-evidence approach was applied to narrative synthesis. Evidence synthesis by vote counting was depicted using harvest plots. The heterogeneous nature of the data prevented a meta-analysis from being appropriate.Results Of the 2,690 studies identified, 117 underwent quality assessment, resulting in 46 studies for narrative synthesis and 38 pertaining to wasting or stunting included in vote counting. The majority of studies were cross-sectional (33 studies).For the permanent dentition, the balance of evidence showed generally no association between caries prevalence or severity with wasting. For the primary dentition, positive associations between dental caries prevalence and severity with wasting, as well as between dental caries prevalence and severity with stunting, were reported. Conclusions Overall, the authors concluded that the balance of evidence favoured an association between dental caries in the primary dentition and undernutrition in children but highlighted the complexity of synthesising dental and nutritional data along with dentition type, age of child participants and income status of countries.