|Assessment of Severity|
Assessing the severity of COPD can be performed in several ways. COPD was historically assessed using FEV1 percentage predicted but recently it has been recognised that there is a wide disparity between lung function and patient symptoms.
Symptom scores such as the MRC (Medical Research Council) dyspnoea score have been found to be more useful as well as functional tests such as the 6-minute walk test. In the academic setting we often use a scoring system know as the St Georges Respiratory Questionnaire (SGRQ).
The SGRQ however takes time to complete (at least 10 minutes) and requires analysis of data (another 20 minutes), however it is useful in assessing the impact of the disease in the patient’s life.
The authors of the SGRQ have developed a new scoring system known as the COPD Assessment Tool (CAT). It is rapid enough in its completion and assessment to be useful in the clinical setting. To help predict life expectancy the BODE index is often used which combines the score of FEV1, 6MW test, BMI and the modified MRC (MMRC).
COPD severity is now graded into mild, moderate, severe and very severe according to the post bronchodilator FEV1 of the patient. This is standardised for age, sex and height. See spirometry section for more details.
CAT (The COPD Assessment Test)
The CAT is a validated, short and simple patient completed questionnaire which has been developed for use in routine clinical practice to measure the health status of patients with COPD. Despite the small number of component items, it covers a broad range of effects of COPD on patients' health. To download the test or find out more information please go to http://www.catestonline.org/
This scoring system was developed to help predict life expectancy in patients with COPD. The BODE index was constructed by broadening existing prognostic indicators and adding independent predictors of mortality to the FEV1. It is much more accurate and precise across the spectrum of COPD than any single prognostic factor. For more details see: