Among patients diagnosed with non-small cell lung cancer, the most common form of lung cancer, a study by scientists at the Harvard School of Public Health. never smoked, but also those who quit on time smoking.

While most studies have compared mortality between current smokers and non-smokers, the new study focused on former smokers to examine the effects of quitting.

The study included 5594 Massachusetts General Hospital patients between 1992 and 2022 with non-small cell lung cancer. it accounts for 85% of all lung cancer cases.. Of these, 795 were never smokers, 3308 were ex-smokers and 1491 were current smokers. During the study period, 79.3% of current smokers, 66.8% of former smokers and 59.6% of non-smokers died.

Although not smoking was associated with a higher chance of survival after a lung cancer diagnosis, the results showed a significant association between lower mortality and not smoking prior to diagnosis. Current smokers had a 68% higher mortality rate, and ex-smokers had a 26% higher mortality rate than non-smokers.

The longer the patient does not smoke, the greater the health benefits. For ex-smokers, doubling the number of years of quitting before diagnosis was significantly associated with increased life expectancy. Conversely, a doubling of years of smoking was associated with shorter survival among current and former smokers diagnosed with lung cancer.

However, the researchers note that the relationship between survival and history of smoking may vary depending on the clinical stage at which lung cancer was diagnosed, and that the study did not take into account the different types of treatment participants received.

Source: RES-IPE