Personality and Psychological Distress: Statistical Mediation Through Constructive and Destructive Coping in Oncological Patients

Background: Personality traits are established correlates of psychological adjustment to cancer, but their relationships with coping styles, anxiety, and depression require further examination. Constructive coping (fighting spirit, positive reappraisal) and destructive coping (helplessness–hopelessness, anxious preoccupation) are hypothesised intermediates in these relationships. This cross-sectional study examined direct and indirect statistical associations in a structural equation model linking the five NEO-FFI personality traits, both coping styles, and anxiety and depression symptoms in patients with cancer. Methods: This multicentre cross-sectional study was conducted between January 2024 to May 2025 in the Department of Clinical Oncology and Radiotherapy and the Department of Oncological Surgery of the Siedlce Oncology Centre, University Hospital No. 4 in Lublin, and University Hospital No. 1 in Lublin, Poland. Statistical analysis was performed on 185 participants. Personality was assessed with the NEO Five-Factor Inventory (NEO-FFI), coping style with the Mini-Mental Adjustment to Cancer (Mini-MAC) scale, and anxiety and depression with the Hospital Anxiety and Depression Scale (HADS). A saturated structural equation model (four multiple regression equations) was estimated, with standardised path coefficients, non-parametric bootstrap (5000 resamples), and 95% bootstrap confidence intervals for direct and indirect effects. All analyses were conducted in R (version 4.2.2) via RStudio (version 2022.12.0), α = 0.05. Personality traits, coping styles, anxiety, and depression were measured concurrently; the specified mediation pathways therefore represent statistical associations rather than evidence of temporal or causal mechanisms. Results: The model explained 52% of the variance in depression, 52% in anxiety, 10% in constructive coping, and 9% in destructive coping. Agreeableness was the strongest positive predictor of constructive coping (β = 0.334, p = 0.001) and a negative predictor of destructive coping (β = −0.199, p = 0.019). Neuroticism and conscientiousness positively predicted destructive coping (β = 0.213, p = 0.011; β = 0.218, p = 0.028). Constructive coping was negatively associated with both depression (β = −0.247, p < 0.001) and anxiety (β = −0.124, p = 0.037), while destructive coping was positively associated with both (β = 0.218, p = 0.002; β = 0.383, p < 0.001). Nominal 95% bootstrap confidence intervals excluded zero for specific indirect associations involving agreeableness and both distress outcomes through both coping styles, and for neuroticism and conscientiousness through destructive coping. Conclusions: Constructive and destructive coping were involved in model-specified indirect associations between personality and psychological distress in cancer patients. Agreeableness was associated with lower distress through both coping styles, while neuroticism and conscientiousness showed positive indirect associations through destructive coping. Concurrent measurement, possible construct overlap, unadjusted demographic and clinical factors, and multiple comparisons limit interpretation. These exploratory findings may inform hypotheses for longitudinal studies; they do not establish causal mediation or the effectiveness of coping-focused interventions.