S42 THE ASSESSMENT OF COUGH SEVERITY WITH A NOVEL COUGH MONITOR

¹A Savani, ¹C Wood, ¹D Cox, ¹T Fleming, ¹S Matos, ²ID Pavord, ¹SS Birring. ¹King’s College Hospital, London, UK, ²Glenfield Hospital, Leiceseter, UK

The assessment of cough has been hampered by the lack of objective tools. The Leicester cough monitor (LCM) is a validated cough monitor that records 24-h cough frequency. The LCM is a lightweight, ambulatory and automated system that consists of a recorder and a microphone. The aim of this study was to use this novel tool to evaluate cough frequency in an outpatient setting.

We recruited 84 patients with chronic cough from our specialist cough clinic (50 women, mean age 55 years) and recorded their 24-h cough frequency. This was compared with subjective parameters of cough severity (visual analogue score (VAS) and quality of life scores (Leicester cough questionnaire, LCQ)). The responsiveness of the LCM was assessed in 21 patients who underwent a 2-week trial of oral prednisolone.

Patients with chronic cough had a mean (SEM) cough frequency of 16 (2) coughs/h. All patients had diurnal variation in cough frequency (21 daytime vs 10 nighttime coughs/h; 95% CI for difference 7 to 15; p<0.001). There was no relationship between cough frequency and age, gender, duration of cough, atopy, meal times or cause of cough. There was a significant correlation between cough frequency and both cough symptoms (VAS; r  =  0.37; p<0.001) and quality of life (LCQ; r  =  −0.41; p<0.001). A reduction in cough frequency was seen in 17 (81%) patients undergoing a trial of prednisolone. The responsiveness of the LCM was good; the effect size for change in cough frequency (difference in mean cough frequency/standard deviation of baseline cough frequency) was 0.6.

This is the first study to report cough frequency using an automated cough monitor in …