Halitosis and Its Association with Sleep Quality and Psychological Factors Among University Students: A Cross-Sectional Study

Introduction: Halitosis is a common oral condition that may negatively affect social interactions, psychological well-being, and quality of life. However, evidence regarding its association with mental health and sleep quality remains inconsistent, particularly among university students. Aim: This cross-sectional study investigated the prevalence of objectively measured halitosis and its association with tongue coating, sleep quality, and symptoms of anxiety, depression, and stress among university students from the metropolitan region of Santos, Brazil. Methods: Sixty-two Brazilian university students enrolled in health-related undergraduate programs participated in the study; most were in the first academic year (61.3%) and resided in the municipality of Santos (59.7%). Halitosis was assessed using a portable breath detector, tongue coating was evaluated using the Coated Tongue Index, sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI), and symptoms of depression, anxiety, and stress were measured using the Depression, Anxiety and Stress Scale (DASS-21). Results: Objectively measured halitosis was identified in 25 participants (40.3%; 95% CI: 29.0–52.7%). The analyses did not provide statistically significant evidence of associations between objectively measured halitosis and tongue coating, sleep quality, or symptoms of anxiety, depression, and stress. Significant positive correlations were identified between stress and sleep disturbance, anxiety and sleep disturbance, and depression and sleep latency, daytime dysfunction, and overall sleep quality. Tongue-cleaning habits were significantly associated with the presence of halitosis, whereas oral mucosal desquamation was less frequent among participants with halitosis. Conclusion: The study did not provide statistically significant evidence of associations between objectively measured halitosis and tongue coating, sleep quality, or psychological symptoms in this population. Significant positive correlations were identified between stress and sleep disturbance, anxiety and sleep disturbance, and depression and sleep latency, daytime dysfunction, and overall sleep quality. These findings highlight the importance of objectively assessing oral malodor in epidemiological studies.