LAUSR

BACKGROUND AND AIMS Oral health related quality of life (OHRQoL) is known to be reduced in disadvantaged populations, including people who inject drugs. Mental health issues, such as depression are also commonly reported. In this study we examined the association between depression and OHRQoL. METHODS Cross-sectional analysis survey data was collected from the Melbourne Injecting Drug User Cohort Study (SuperMIX) of people who inject drugs (N = 982). Three measures derived from the Oral Health Impact Profile (OHIP-14) were used to assess OHRQoL: Prevalence (reporting one or more dental issue "Very often" or "Fairly often" in the previous year), Extent (number of items reported either "Very often" or "Fairly often") and Severity (summary score of all ordinal responses). Regression analyses assessed the association between depression, indexed as scoring above 10 on the Patient Health Questionnaire (PHQ-9), and OHIP-14 measures, adjusted for sociodemographic, drug use and dental service utilisation variables. RESULTS Overall, participants had low levels of OHRQoL, indexed through OHIP-14 scores (46% exhibiting prevalence, mean extent of 2.35 and mean severity of 12.72). Depression was associated with increases in all OHIP-14 measures, after adjustment for potential confounders. CONCLUSIONS We found a significant association between depression and poor OHRQoL in this sample of people who inject drugs. Further research using a longitudinal frame is needed to determine the direction of this relationship. Interventions to improve oral health of people who inject drugs are urgently needed, and these may benefit mental health outcomes for people who inject drugs.