Sensitivity of the COPD assessment test (CAT questionnaire) investigated in a population of 681 consecutive patients referring to a lung clinic: the first Italian specific study

BACKGROUND Chronic Obstructive Pulmonary Disease (COPD) is a major cause of morbidity and mortality at global level even if still underestimated. The insufficient use of specific tools for an objective definition and staging, the inadequate awareness of COPD, but also a difficult patient-to-doctor communication, can contribute to the poor management of COPD. A very simple, short and sensitive questionnaire (the "COPD Assessment Test" - CAT questionnaire) is now available for assessing the impact of COPD on the patient's health. The present study was designed to provide such evidence using data generated throughout Italy. METHODS The Italian validated version of the CAT questionnaire was distributed to 681 consecutive COPD patients of different severity (males = 480), well matched for age, gender, smoking habit, geographical distribution, BMI, dyspnoea score and educational level. The CAT score variability was investigated vs all anagraphic, and clinical variables, and spirometric indices of lung function (regression). No Italian data are available to our knowledge on the CAT use, neither in General Medicine, nor in the specialist setting. RESULTS Data of this study confirmed that the CAT questionnaire is a sensitive, simple, and quick tool for assessing the respiratory status of COPD patients. The CAT score proved not conditioned by the patient's age, gender, body size, geographical origin, and educational level. It was inversely correlated with the spirometric values, even if not uniquely linked to them. CONCLUSIONS The CAT score does not represent a surrogate measurement of lung function: it is an instrument which focuses on different areas of respiratory health in COPD patients, thus providing an useful and objective tool for the long-term clinical and therapeutic monitoring of COPD patients in the specialist outpatient setting.