Starting with the GOLD chronic bronchitis staging system, this method uses the FEV1 metric for its staging. FEV stands for forced expiratory volume, and FEV1 refers to the amount of air exhaled during the first forced breath. Stage I is mild and life expectancy is normal. Sufferers in this stage will experience a somewhat limited airflow and a mucus-producing cough every once in a while, but it does not interfere with daily life. Stage II is moderate and life expectancy is 5 or more years with treatment. Sufferers in this stage will experience a worsening airflow and become short of breath after any sort of physical activity. This is when most people seek treatment.
Stage III is severe and life expectancy is 5 or more years with treatment. Sufferers in this stage will experience an even greater worsening of airflow and shortness of breath. Normal exercise is no longer possible and symptoms flare up often. This worsening or flare-up of symptoms is called an exacerbation of COPD. Stage IV is very severe and limited life expectancy is common, even with treatment. Sufferers in this stage will experience very limited airflow as well as more intense and regular flare-ups. Moreover, individuals are usually on supplemental oxygen, and quality of life is generally poor.
Moving onto the BODE chronic bronchitis staging system, this is a more complex method that uses various metrics to determine one’s quality of life with COPD. Due to this system’s comprehensive collection of information, it is generally the preferred method. Body mass determines whether an individual is underweight, overweight, or obese. This is important because nutrition and weight management are both things that sufferers of COPD are known to struggle with. Airflow obstruction uses the FEV1 metric as well as other pulmonary function tests to see how well the lungs are working.
Dyspnea is a medical term that refers to shortness of breath. As such, this metric indicates the degree to which shortness of breath is affecting an individual’s life. Exercise capacity is measured using a 6-minute walk test, which evaluates how far one can walk on a flat, hard surface at a quick pace. It’s a reflection of a person’s exercise tolerance and ability to perform everyday physical tasks. Together, the measurements of the BODE system make up the BODE index, which is a helpful tool for survival prediction as well as estimated life expectancy.