What is the Chronic Obstructive Pulmonary Disease (COPD) assessment test?

From the Guidelines

The COPD Assessment Test (CAT) is a recommended tool for assessing the impact of Chronic Obstructive Pulmonary Disease (COPD) on a patient's health status, as it provides a comprehensive evaluation of symptoms beyond just breathlessness 1. The CAT is an 8-item questionnaire that measures the effect of COPD on daily life, with scores ranging from 0-40, where higher scores indicate more severe impact.

• The test evaluates symptoms such as cough, phlegm, chest tightness, breathlessness during activities, activity limitations, confidence leaving home, sleep quality, and energy levels.
• The CAT is suitable for initial assessment and ongoing monitoring of COPD patients, with scores above 10 generally indicating medium to high impact of the disease.
• Healthcare providers should administer this test at diagnosis and periodically (typically every 3-6 months) to track disease progression and treatment effectiveness, as recommended by the global strategy for the diagnosis, management, and prevention of chronic obstructive lung disease 1. The CAT complements other assessments like spirometry and exacerbation history in the comprehensive management of COPD, helping clinicians make more informed treatment decisions and adjust management plans accordingly.
• Its value lies in quantifying subjective symptoms that significantly affect quality of life but might not be captured by objective measurements alone.
• The use of the CAT is supported by the American Journal of Respiratory and Critical Care Medicine, which emphasizes the importance of a comprehensive assessment of symptoms in COPD patients 1.

From the FDA Drug Label

The FDA drug label does not answer the question.

From the Research

Overview of the COPD Assessment Test

• The COPD Assessment Test (CAT) is an eight-item questionnaire designed to assess and quantify the impact of COPD symptoms on health status 2.
• The CAT score provides a reliable measure of exacerbation severity, with higher scores indicating more severe symptoms 2.
• Baseline CAT scores are elevated in frequent exacerbators, and CAT scores increase at exacerbation, reflecting severity as determined by lung function and exacerbation duration 2.

Clinical Outcomes Prediction and Classification

• The CAT score can indicate risk of exacerbation, depression, acute deterioration in health status, and mortality 3.
• The CAT may be used as a complementary tool in a patient's clinical assessment to predict COPD exacerbation, health status deterioration, depression, and mortality 3.
• However, the interpretation of the meta-analysis does not support the use of the recommended cutoff points of ≥10 for CAT and ≥2 for mMRC as equivalents for the purpose of assessing patient symptoms 3.

Response to Pulmonary Rehabilitation

• The CAT score improves in response to pulmonary rehabilitation, with a mean change of 2.9 points, and can distinguish categories of response 4.
• The CAT score is simple to implement as an outcome measure and can be used to assess the effectiveness of pulmonary rehabilitation programs 4.
• The CAT score is immediately responsive to pulmonary rehabilitation and remains improved at 6 months, with no significant difference in the short and medium term changes in the CAT and CRQ-SR following PR 5.

Psychometric Properties

• The CAT has good internal consistency, test-retest reliability, and convergent validity, with scores differing with GOLD stages, exacerbation, and mMRC grades 6.
• The CAT is responsive to interventions, although the minimum clinically important difference (MCID) remains debatable, with one study reporting an MCID of 2 units using the anchor-based approach 6.