PURPOSE: The Leicester Cough Questionnaire (LCQ)is used to determine health status in patients with chronic cough. Recently, the Dutch language version of the LCQ has been validated. The next step is to determine what change in LCQ scores is significant (i.e. what is the minimal clinically important difference (MCID)). This study aimed to identify the MCID of the LCQ after 6 months in terms of patient referencing. Moreover, we were interested which baseline factors were predictive of reaching the MCID after six months.
METHODS: 335 patients visiting the outpatient cough clinic were asked to complete the LCQ on the first visit and after 6 months. A Global Rating of Change (GRC) assessment was taken to establish the MCID by patient referencing. Univariate and logistic regression analyses were preformed to assess potential predicting baseline values (sex, productive cough, smoking, hay-fever, nose complaints??, gastric complaints, use of ACE inhibitors, use of gastric acid inhibitors, use of inhaled medication, age, clinical signs of anxiety or depression).
RESULTS: 308 of the 335 patients (mean age 60±11; 101 men (30%) completed both LCQ's and the GRC. LCQ total, physical, psychological and social scores, as indicated by patient referencing in terms of the GRC (-3 or -2 or +2, or +3; n=55), were respectively 2.81, 0.84, 0.96,1.28. The use of gastric acid inhibitors was predictive of reaching the MCID in LCQ total, physical and social scores (OR's (95% confidence interval) were respectively 2.1 (1.2; 3.7); 2.4 (1.4; 4.3); 2.0 (1.1; 3.6). Depression was predictive of reaching the MCID in psychological and social domain (OR's respectively 2.2 (1.0; 4.7); 2.8 (1.2; 6.2).
CONCLUSION: Rounded, the MCID of the LCQ total is 3 points (1 point/domain). Patients with clinical signs of depression or using gastric acid inhibitors were more likely to reach the MCID than patients without clinical signs of depression or not using gastric acid inhibitors.
CLINICAL IMPLICATIONS: Patients with either signs of depression or on gastric acid inhibitors were most likely to benefit from our cough clinic.
DISCLOSURE: Lenny Brokkaar, No Financial Disclosure Information; No Product/Research Disclosure Information