Smoking cessation, not reduction reduces risk of cardiovascular disease: Study

Republic of Korea: A population study by Su-Min Jeong and the team revealed that smoking cessation, but not reduction, reduces the risk of cardiovascular disease (CVD). Also, a sustained cessation of smoking reduced stroke and mortality chances. The findings of the study are published in the European Heart Journal.

According to the Centers for Disease Control and Prevention (CDC), smoking cigarettes increases the risk of cardiovascular diseases (CVD), stroke, respiratory problems, etc. Tobacco use is the most common preventable cause of death however reduction doesn't help its risk factors. Su-Min Jeong and the team, therefore, aimed to assess the association of smoking cessation and reduction with the risk of cardiovascular disease.

The study included a total of 8,97,975 current smokers aged ≥40 years who had undergone two consecutive national health examinations (in 2009 and 2011) were included. Participants were classified as quitters (20.6%), reducers I (≥50% reduction, 7.3%), reducers II (20–50% reduction, 11.6%), sustainers (45.7%), and increasers (≥20% increase, 14.5%). During 55,75,556 person-years (PY) of follow-up, 17748 stroke (3.2/1000 PY) and 11,271 myocardial infarction (MI) (2.0/1000 PY) events were identified.

The results of the study were

• Quitters had significantly decreased risk of stroke [adjusted hazard ratio (aHR) 0.77; absolute risk reduction (ARR) −0.37, and MI (aHR 0.74; ARR) compared to sustainers after adjustment for demographic factors, comorbidities, and smoking status

• The risk of stroke and MI incidence in reducers I (aHR 1.02 and aHR 0.99 respectively) and reducers II (aHR 1.00 and aHR 0.97, respectively) was not significantly different from the risk in sustainers.

• Further analysis with a subgroup who underwent a third examination (in 2013) showed that those who quit at the second examination but had started smoking again by the third examination had a 42–69% increased risk of CVD compared to sustained quitters.

Jeong and the team concluded that "Smoking cessation, but not reduction, was associated with reduced CVD risk. Our study emphasizes the importance of sustained quitting in terms of CVD risk reduction."

Reference: 

Su-Min Jeong, Keun Hye Jeon, Dong Wook Shin, Kyungdo Han, Dahye Kim, Sang Hyun Park, Mi Hee Cho, Cheol Min Lee, Ki-Woong Nam, Seung Pyo Lee, Smoking cessation, but not reduction, reduces cardiovascular disease incidence, European Heart Journal, Volume 42, Issue 40, 21 October 2021, Pages 4141–4153, https://doi.org/10.1093/eurheartj/ehab578