Prevalence of psychomorbidity among patients with chronic cough

Chronic cough may cause significant emotional distress and although patients are not routinely assessed for co-existent psychomorbidity, a cough that is refractory to any treatment is sometimes suspected to be functional in origin. It is not known if patients with chronic cough referred for specialist evaluation have emotional impairment but failure to recognise this may influence treatment outcomes. In this cross-sectional study, levels of psychomorbidity were measured in patients referred to a specialist cough clinic.

Fifty-seven patients (40 female), mean age 47.5 (14.3) years referred for specialist evaluation of chronic cough (mean cough duration 69.2 (78.5) months) completed the Hospital Anxiety and Depression (HAD) scale, State Trait Anxiety Inventory (STAI) and the Crown Crisp Experiential Index (CCEI) at initial clinic presentation. Subjects then underwent a comprehensive diagnostic evaluation, after which they were classified as either treated cough (TC) or idiopathic cough (IC). Questionnaire scores were compared between TC (n = 42) and IC (n = 15).

Using the HAD scale, 33% of all cough patients were identified as anxious, while 16% experienced depression. The STAI scores suggested moderate or high trait anxiety in 48% of all coughers. Trait anxiety was significantly higher among TC (p < 0.001) and IC patients (p = 0.004) compared to a healthy adult population. On the CCEI, mean scores on the phobic anxiety, somatisation, depression, and obsession subscales were significantly higher among all cough patients than the published mean scores for healthy controls. Only state anxiety was significantly higher in IC patients compared with TC patients (p < 0.05).

Patients with chronic cough appear to have increased levels of emotional upset although psychological questionnaires do not readily distinguish between idiopathic coughers and those successfully treated.