Methods: A cross sectional survey was conducted on a convenience sample of homeless people, gathered at homeless health clinics, hostels and day centres in 7 NHS Board areas in Scotland. All consenting participants were invited to complete a questionnaire to assess their physical and mental health, dental anxiety and oral health-related quality of life. Participants received an oral examination, which assessed their obvious decay experience, periodontal health and oral pathology. Analysis was conducted using AMOSv17 to test for direct and indirect effects with the aid of intensive resampling methods.
Results: 456 homeless people consented to take part, of which 265 (58%) yielded complete data sets. 67% were male. 57% were aged between 16 and 34 years. Three latent variables, decayed and missing teeth, dental anxiety (MDAS: 5 items), and depression (CESD: 3 factors), and a single variable for oral health-related quality of life (OHIP total scale) were used in a hybrid structural equation model. Decayed and missing teeth affected depression through indirect pathways (total standardised indirect effects = 0.45, p< .001), via oral health-related quality of life and dental anxiety (X² = 70.38; df = 40; CFI = 0.98; RMSEA = 0.054 [90% CI: 0.03, 0.07]).
Conclusions: Depression in Scottish homeless people is affected by oral health-related factors. Decayed and missing teeth influence depression primarily through the psychological constructs of oral health-related quality of life and, to a lesser extent, dental anxiety.