Results from a randomised controlled trial (RCT) of cognitive behavioural therapy (CBT) with respiratory nurses in patients with chronic obstructive pulmonary disease (COPD). Comparison of responders compared to non-responders at primary outcome.

<bold>Background:</bold> Symptoms of anxiety & depression are important comorbidities in COPD. The under diagnosis and treatment can adversely affect patient outcomes (physical functioning, breathlessness, exacerbation rates, physical activity, quality of life, use of health care resources and mortality). <bold>Aims:</bold> To assess factors to predict who would improve at the primary endoint of a RCT of a nurse led CBT intervention for symptoms of anxiety. <bold>Methods:</bold> Data was collected for 236 patients completing the primary endpoint (3 months following randomisation). Logistic regression analysis was performed on all patients completing the primary outcome and compared responders (improving >1.5 on the Hospital Anxiety & Depression (HADS) Anxiety subscale) and those who did not (non responders). Baseline continuous variables were assessed including age, HADS-Anxiety & Depression scores, CAT Questionnaire and EQ-5D utility scores at baseline. <bold>Results:</bold> 132 (56%) patients reached the primary outcome of >1.5 on HADS-Anxiety scale. The strongest predictor of responding, was a HADS-Anxiety score at baseline, with an odds ratio of 1.20 (p=0.001 95% CI 1.07 – 1.34). The second was age, with an odds ratio of 1.04 (p=0.005 95% CI 1.01 – 1.08). <bold>Conclusion:</bold> Those with higher HADS-anxiety scores and older patients were most likely to attain a minimally clinical important difference in anxiety symptoms. Future trials should include patients with higher HADS scores, as these are the most likely to respond.