Smoking Is Even More Damaging to the Heart Than Thought

New research finds that smokers have weaker hearts than non-smokers

By EUROPEAN SOCIETY OF CARDIOLOGY 

According to a new study presented at the European Society of Cardiology’s ESC Congress 2022, smokers have weaker hearts than non-smokers.^[1] The research found that the more people smoked, the worse their heart function became. Fortunately, some function was restored when people kicked the habit.

“It is well known that smoking causes blocked arteries, leading to coronary heart disease and stroke,” said study author Dr. Eva Holt of Herlev and Gentofte Hospital, Copenhagen, Denmark. 

“Our study shows that smoking also leads to thicker, weaker hearts. It means that smokers have a smaller volume of blood in the left heart chamber and less power to pump it out to the rest of the body. The more you smoke, the worse your heart function becomes. The heart can recuperate to some degree with smoking cessation, so it is never too late to quit.”

Tobacco kills more than eight million people each year, according to the World Health Organization (WHO).^[2] Cigarette smoking is responsible for 50% of all avoidable deaths in smokers, with half of these due to atherosclerotic cardiovascular diseases such as heart attack and stroke.^[3] The detrimental effects of smoking on the arteries and arterial diseases such as heart attack and stroke are well established.^[4]

Additionally, studies have shown that smoking is associated with a higher risk of heart failure, where the heart muscle does not pump blood around the body as well as it should, usually because it is too weak or stiff. This means that the body does not receive the oxygen and nutrients it needs to function normally. The link between smoking and heart structure and function has not been fully investigated. Therefore, this study explored whether smoking was related to changes in the structure and function of the heart in people without cardiovascular disease, and the effect of changing smoking habits.

The 5^th Copenhagen City Heart Study, which investigated cardiovascular risk factors and diseases in the general population, provided data for the study. A total of 3,874 participants aged 20 to 99 years without heart disease were enrolled. A self-administered questionnaire was utilized to obtain information on smoking history and to estimate pack-years, or the total amount of cigarettes smoked throughout the course of a person’s lifetime. 20 cigarettes smoked per day for a year constitutes one pack-year.

Study participants had an ultrasound of the heart, called echocardiography, which provides information about its structure and how well it is working. The scientists compared the echocardiography measures of current smokers versus never smokers after adjusting for age, sex, body mass index, high cholesterol, hypertension, diabetes, and lung function.

The average age of participants was 56 years old and 43% were women. Nearly one in five participants were current smokers (18.6%), while 40.9% were former smokers and 40.5% had never smoked. Compared to never smokers, current smokers had weaker, thicker, and heavier hearts. Increasing pack-years were associated with pumping less blood. Dr. Holt explained: “We found that current smoking and accumulated pack-years were associated with worsening of the structure and function of the left heart chamber – the most important part of the heart. Furthermore, we found that over a 10-year period, those who continued smoking developed thicker, heavier, and weaker hearts that were less able to pump blood compared to never smokers and those who quit during that time.”

She concluded: “Our study indicates that smoking not only damages the blood vessels but also directly harms the heart. The good news is that some of the damage is reversible by giving up.”

References and notes:

The abstract “The effects of smoking on cardiac structure and function in a general population” was presented during the session Risk stratification with echocardiographic parameters on Friday, August 26.

World Health Organization tobacco fact sheet: https://www.who.int/news-room/fact-sheets/detail/tobacco.

“2021 ESC Guidelines on cardiovascular disease prevention in clinical practice: Developed by the Task Force for cardiovascular disease prevention in clinical practice with representatives of the European Society of Cardiology and 12 medical societies With the special contribution of the European Association of Preventive Cardiology (EAPC)” by Frank L J Visseren, François Mach, Yvo M Smulders, David Carballo, Konstantinos C Koskinas, Maria Bäck, Athanase Benetos, Alessandro Biffi, José-Manuel Boavida, Davide Capodanno, Bernard Cosyns, Carolyn Crawford, Constantinos H Davos, Ileana Desormais, Emanuele Di Angelantonio, Oscar H Franco, Sigrun Halvorsen, F D Richard Hobbs, Monika Hollander, Ewa A Jankowska, Matthias Michal, Simona Sacco, Naveed Sattar, Lale Tokgozoglu, Serena Tonstad, Konstantinos P Tsioufis, Ineke van Dis, Isabelle C van Gelder, Christoph Wanner, Bryan Williams and ESC Scientific Document Group, 30 August 2021, European Heart Journal.
DOI: 10.1093/eurheartj/ehab484

Centers for Disease Control and Prevention smoking and cardiovascular disease fact sheet: https://www.cdc.gov/tobacco/data_statistics/sgr/50th-anniversary/pdfs/fs_smoking_CVD_508.pdf.

Funding: The Copenhagen City Heart Study is funded by The Danish Heart Foundation and The Metropolitan Region of Denmark.