The association between halitosis and oral-health-related quality of life: A systematic review and meta-analysis

Aim To investigate whether halitosis is associated with impaired oral-health-related quality of life (OHRQoL). Materials and Methods This is a systematic review of the literature. Electronic searches were performed in PubMed via Medline, Web of Science, Scopus, and EMBASE up to and including June 2021. Observational studies that assessed halitosis in association with OHRQoL were included. The pooled standardized mean difference (SMD) was estimated by meta-analysis. Results Thirteen studies were included in the review; however, the meta-analysis included only 10 studies, all cross-sectional, comprising 2692 individuals. The overall meta-analysis showed an association between halitosis and impaired OHRQoL (SMD 0.51; 95% confidence interval 0.27-0.75). Subgroup analyses, however, indicated that this association remained only among adults. Neither the OHRQoL instrument nor the halitosis assessment method, or the cultural background, influenced the pooled estimates. Meta-regression analyses revealed that the OHRQoL instrument, the halitosis assessment method, and the sample composition did not explain the between-study heterogeneity. Methodological quality appeared to explain 20% of the overall heterogeneity, as studies with high risk of bias overestimated the magnitude of the association. Conclusion Our findings suggest that halitosis is associated with impaired OHRQoL.