Researchers found that there was “no significant difference in lung function decline rates” when evaluating lung functions according to the GOLD system, which classifies COPD patients.
There were a total of 175 patients included in this study, with 33.1% being classified in group A, 25.7% group B, 8,6% group C, and 32.6% in group D. The researchers did not find any significant difference in lung function decline between the four groups. Groups A and B are considered low risk groups, whereas C and D are high risk groups.
Although it may seem that lung function decline would be worse among those patients in the high risk groups C and D, the researchers offer several possible explanations for the similarity in decline across all four groups. For example, exacerbation history may play a role in lung function decline and there is no evidence that worse symptoms lead to a faster decline.
Despite some limitations, such as the fact that all of the participants were Korean and male, the researchers concluded that the GOLD group classification system could not predict lung function decline. They suggest that the older method of using postbronchodilator forced expiratory volume in one second is a better predictor of lung function decline.