Adherence To Prophylactic Swallowing Exercises in Head and Neck Cancer Patients (PRESTO-TRIAL) - the ROLE of Personality Characteristics

Prophylactic swallowing exercises (PSE) can mitigate (the consequences of) radiation associated dysphagia (RAD) in head and neck cancer (HNC) patients, provided patients adhere to a high-intensity program. However, patient adherence, a multifactorial concept influenced by several confounders, has been found to vary considerably between studies and individuals. PSE-related adherence confounders such as gender, smoking at baseline, baseline depression and high baseline fatigue levels have already been postulated. The influence of personality on adherence to PSE has not yet been investigated. Therefore, the aim of this secondary analysis of the Presto-trial is to examine the influence of personality traits on overall adherence rates to a PSE-program. One hundred fifty patients with a stage III or IVA-B (TNM7) newly diagnosed squamous cell carcinoma of the oropharynx -treated with (chemo)radiotherapy (C)RT - were included in the PRESTO-trial. One hundred sixteen out of the 150 participants completed the NEO Five Factor Inventory (NEO-FFI) personality questionnaire prior to starting RT. The NEO-FFI is a validated 60 item self-report questionnaire with 12 items per personality trait (neuroticism, extraversion, altruïsm, conscientiousness and openness). Statistical analysis was performed using simple and multiple regression models for the 5 personality traits. This study shows that the personality trait openness significantly influences overall adherence rates to PSE in HNC (p = 0.047). Higher scores on the personality trait openness increase overall adherence rates (β = 0.058, SE = 0.0290). Although, this singular statistical result has a very small effect size (OR 1.06), meaning that it is not likely a meaningful difference to consider any practice change. The personality traits extraversion, neuroticism, conscientiousness and altruism are not significantly related to overall adherence during PSE. This study is the first to explore the relationship between personality traits and adherence to PSE in HNC. While openness showed a statistically significant association with overall adherence, the effect size was very small and is unlikely to be of clinical relevance. No other personality traits demonstrated a significant relationship with adherence.