Chronic bronchitis

VA rates chronic bronchitis under Diagnostic Code 6600 based on how much your lungs can move and exchange air, measured by breathing tests. There are four possible ratings: 10%, 30%, 60%, and 100%.

The tests that drive the rating are FEV-1 (the amount of air you can force out in one second, expressed as a percentage of the predicted normal value for someone your age and size), the ratio of FEV-1 to FVC (Forced Vital Capacity), and DLCO (SB) (how well your lungs transfer carbon monoxide into the blood, also expressed as a percentage of predicted). At the 60% and 100% levels, maximum oxygen consumption during exercise can also be used.

A 10% rating applies when FEV-1 is 71–80% predicted, FEV-1/FVC is 71–80%, or DLCO (SB) is 66–80% predicted. A 30% rating applies at FEV-1 56–70%, FEV-1/FVC 56–70%, or DLCO (SB) 56–65%. A 60% rating applies at FEV-1 40–55%, FEV-1/FVC 40–55%, DLCO (SB) 40–55%, or maximum oxygen consumption of 15–20 ml/kg/min with a cardiorespiratory limit. A 100% rating applies when FEV-1 or FEV-1/FVC falls below 40%, DLCO (SB) is below 40%, maximum oxygen consumption is below 15 ml/kg/min, or you have cor pulmonale, right ventricular hypertrophy, pulmonary hypertension, an episode of acute respiratory failure, or a requirement for outpatient oxygen therapy.