Former smokers retain lasting lung damage despite quitting

· News-Medical

A new study by a team of McGill researchers could help explain why people who have quit smoking remain at elevated risk of lung disease long after their last cigarette.

"Our findings show that while some damage appears reversible, other changes persist long after people stop smoking," she said.

Mapping recovery after smoking

Using publicly available data, the researchers analyzed more than 100,000 lung cells from 21 people: nine who had never smoked, five current smokers and seven former smokers. The data captured molecular activity across more than 40 lung cell types, offering a highly detailed picture of how the lungs respond to smoking and of recovery after quitting.

Some lung cells recovered after smoking ended, while others showed lasting changes in genes linked to tissue structure, immune function and blood vessel health. In some cases, former smokers displayed molecular patterns not seen in either current smokers or people who had never smoked, suggesting quitting leaves its own biological signature on the lung.

Could inform treatment

"These findings are an important step toward understanding what damage caused by smoking can heal and what may be permanent," said first author Nicole Heimbach, a doctoral student at McGill. "By knowing what damage remains after quitting, we can better understand how smoking-related diseases develop and how to treat them."

About the study

Source:

McGill University

Journal reference: