“Healthy” Smokers’ Lungs: Mystery Solved!

It makes sense to assume that all smokers have unhealthy and blackened lungs, so you might be interested to know that some smokers actually have surprisingly healthy lungs, despite a lifetime of smoking. Of course, this is something that has puzzled scientists for quite some time... Until now! This ongoing mystery has finally been explained by researchers in the UK, funded by the Medical Research Council. And what's more, the findings could eventually lead to new medicines for improving lung function and health in the future. Led by the University of Nottingham's Professor Ian Hall and the Univerity of Leicester's Professor Martin Tobin, the study was published in The Lancet Respiratory Medicine and presented to the European Respiratory Society (ERS). ASH (Action on Smoking and Health) says that there are around 10 million adult smokers in the UK, which is about a sixth of the population. Many of these will develop lung disease at some point in their life - but not all of them. And there will be plenty of people who will develop it who haven't smoked a single cigarette in their life. This latest study saw researchers analysing the health of more than 50,000 people who are all part of the UK Biobank, a major national health resource and charity in its own right. The UK Biobank aims to improve the prevention, diagnosis, and treatment of various serious and life-threatening illnesses. It has recruited around half a million volunteers who have all agreed to have their health indepthly analysed, and the results of which used for research. As you can imagine, this project provides a huge amount of health and genetic data. Using this information, the researchers specifically looked into COPD, which stands for Chronic Obstructive Pulmonary Disease. This condition covers a range of problems, including repeat chest infections, breathlessness, coughing, bronchitis, and emphysema. We should also note that although smoking is known to increase the risk of heart disease and some cancers, the focus was on COPD and so these illnesses were not considered in the study. The analysis of both smokers and nonsmokers, as well as those with COPD and without, showed that some people had favourable mutations in their DNA that enhanced lung function and reduced the risk of COPD. Professor Tobin said that these mutated genes seem to affect the way the lungs grow and respond to injury, such as that sustained during smoking. He explained that the biggest lifestyle risk factor for developing the condition is smoking, and "good" genetics play a big part in those few smokers who don't get it. And now, thanks to the research, he is finally able to explain why this is. The team also uncovered parts of the genetic code that were more common in smokers than in nonsmokers. They seemed to subtlely alter the brain's function and therefore how easily a person can become addicted to nicotine. However, these findings still need to be confirmed. "[The findings offer] fantastic new clues about how the body works that we really had little idea about before," Professor Tobin said. "It is those things that are likely to lead to some really exciting breakthroughs for drug development." While this is all very well, the professor does add that the best thing a person can do to avoid COPD or any other smoking-related diseases is to quit smoking altogether. Professor Hall, the other lead in the study, explained that our genes influence the production of the proteins that are targeted by the drugs used to prevent or target diseases in our bodies. "Understanding how genes are involved... can help us design and develop better and more targeted treatments that are more likely to be effective and have fewer side effects," he said. Commenting on the study, the British Lung Foundation's Head of Research Ian Jarrold said that the findings represent a significant step forward in achieving a clearer picture of lung health. He added that understanding genetic predisposition would help them to develop new treatments for lung disease, as well as teach "otherwise healthy people how to better take care of their lungs".