Prevalence and determinants of anxiety in amyotrophic lateral sclerosis

Background Clinically relevant anxiety can be detected in patients with amyotrophic lateral sclerosis (ALS), but its prevalence and determinants have not yet been fully assessed. Aims This study aimed at assessing the prevalence and clinical underpinnings of anxiety in ALS. Method Non-demented ALS patients (N = 433) and healthy controls (N = 313) were administered the State- and Trait-Anxiety Inventory - Form Y (STAI-Y1 for state-anxiety and STAI-Y2 for trait-anxiety) and the Beck Depression Inventory (BDI). Patients were further assessed for cognition (Edinburgh Cognitive and Behavioural ALS Screen), behaviour (Frontal Behavioural Inventory) and motor status (disease duration, ALS Functional Rating Scale-Revised and progression rate). The prevalence of clinically significant state- and trait-anxiety were estimated by applying age-stratified cut-offs to STAI-Y1/-Y2 t-scores. Linear and logistic regressions were run to test the determinants of STAI-Y1/-Y2 scores. Results STAI-Y1 and -Y2 scores above cut-off were detected in 18.2 and 13.9% of patients, respectively - with proportions being higher in cases versus controls (ps < 0.001). BDI, but neither cognitive/behavioural nor motor variables, was identified as a significant predictor of STAI-Y1/-Y2 scores (ps < 0.003). The cognitive-affective subscale of BDI was the sole predictor of scores above cut-off on both STAI-Y1 and STAI-Y2 (ps < 0.001). Conclusions Clinically significant levels of state- and trait-anxiety occur in ∼18 and ∼14% of non-demented ALS patients, respectively, mostly driven by cognitive and affective facets of depression, and are independent of motor and cognitive/behavioural features.