The risk of developing COPD could be 50% greater for women as it is for men, according to a new diagnostic method utilized by researchers from Lund University Sweden. Researchers noted the finding means gender may be an independent risk factor for developing the disease.

“We see a clear increased risk for women contracting COPD compared with the risk for men. And it applies even when other risk factors, such as smoking and age, are taken into consideration,” said Johannes Luoto, a researcher at Lund University and a doctor at the geriatric clinic of Skåne University Hospital.

It was previously not certain whether there was a gender difference for the risk of developing COPD, and that is partly due to the fact that there are few studies that examine who is at risk for the disease. Another factor is that there has been a recent change in the way that COPD is diagnosed.

“The few studies that have been done use methods to interpret pulmonary function involving spirometry test criteria which the European and American lung research organizations ERS and ATS now consider outdated and unable to produce reliable results,” said Luoto. “These older methods do not consider the age or sex of the examined subject when interpreting the lung function even though we know that normal aging effects lungfunction and suspect that there may be differences between sexes.”

Besides the effects of advanced age and smoking, researchers using the more modern method LLN (Lower Limit of Normal) in their study have seen clear differences between the genders for the risk of developing COPD. There was previous evidence that women’s airways could be more sensitive than men’s, but the older diagnostic methods have not shown with any certainty that there is a difference between the genders regarding the risk for contracting COPD.

“Our study is one of the first that uses more advanced diagnostic criteria, which take into consideration factors such as gender and age before interpretation of the spirometry results and deciding whether you have COPD or not,” Luoto added.