Associations between depression and gingivitis among adolescents resident in semi-urban South-West Nigeria

OBJECTIVE: None of the past studies that had showed a linked between oral and mental health among adolescents was conducted in Nigeria. The objective of this study was to determine the association between gingivitis and depression among adolescents in Ile-Ife, South-West Nigeria. METHODS: This cross-sectional study collected data through a household survey conducted between December 2018 and January 2019. Adolescents aged 10 to 19 years old were identified using multistage sampling. The study outcome measure was gingivitis, measured by the Löe and Silness gingival index. The explanatory variable was depression, measured by the Patient Health Questionnair. Confounders considered were age, sex, socioeconomic status, frequency of daily tooth brushing, oral hygiene status (measured by the plaque index), consumption of refined carbohydrates in-between meals, use of dental floss, and history of dental service utilization in the past 12 months. A logistic regression model was constructed to determine risk indicators for moderate/severe gingivitis. Additionally, modification of associations between dependent variables and the significant risk indicators of depression was assessed. RESULTS: Mean plaque index for the 1,087 adolescent participants enrolled in the study was 0.80. We found a prevalence of 8.5% for moderate/severe gingivitis and 7.9% for depression. In adjusted regression, there were significant associations between the presence of moderate/severe gingivitis and consumption of refined carbohydrates in-between meals (OR 1.94, 95% CI 1.14, 3.28) and plaque index (OR 16.56, 95% CI 10.03, 27.33). Depression also significantly modified the association between plaque index and the presence of moderate/severe gingivitis (P < 0.0001), with a stronger association observed with mild depression (OR 24.75, 95% CI 3.33, 184.00) compared with no depression (OR 15.47, 95% CI 9.31, 25.69), with no significant modification for the association with frequent consumption of refined carbohydrates (P = 0.06). CONCLUSION: Although there was no significant association between gingivitis and depression among our adolescent Nigerian cohort, depression significantly modified the association between plaque index score and moderate/severe gingivitis.