Smoking not only damages the blood vessels, but also directly harms the heart, a new study found. Photo by Myriams-Fotos/Pixabay
Smoking causes worse damage to the heart than experts previously thought, affecting its structure and function and making it thicker, heavier and weaker over time, a new study warns.
The bottom line is that smokers have weaker hearts than nonsmokers, and the more people smoke, the worse their heart function becomes. But kicking the habit can restore some heart function.
That’s according to a Danish study whose poster was released Thursday. Its presentation is scheduled for Friday at the European Society of Cardiology’s Congress 2022 in Barcelona, Spain.
“It is well known that smoking causes blocked arteries, leading to coronary heart disease and stroke,” the study’s author, Dr. Eva Holt of Herlev, and Gentofte Hospital in Copenhagen, Denmark, said in a news release.
“Our study indicates that smoking not only damages the blood vessels, but also directly harms the heart,” she said.
The new research, by showing that smoking also leads to thicker, weaker hearts, “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,” Herlev said.
In the United States, tobacco use is the leading preventable cause of death, and cigarette smoking causes about one of every five deaths annually, much of it related to cardiovascular disease, according to the Centers for Disease Control and Prevention.
The researchers noted that 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.
They said the detrimental effects of smoking on the arteries and arterial diseases, such as heart attack and stroke, are well-established. And studies also have linked smoking to a higher risk of heart failure.
But the investigators said the link between smoking and heart structure and function has not been fully examined.
So they set off to investigate whether smoking was related to changes in the heart’s structure and function in people without cardiovascular disease, and they also explored the effects of changing smoking habits.
The researchers used data from the Fifth Copenhagen City Heart Study that looked at cardiovascular risk factors and diseases in the general population, enrolling 3,874 participants 20 to 99 years old without heart disease into the study.
Participants filled out a questionnaire on their smoking history to estimate “pack-years” — one pack-year being defined as 20 cigarettes smoked every day for one year.
Participants averaged 56 years old, and about six in 10 were men. They had an ultrasound of the heart, called echocardiography, to obtain information about its structure and its level of functioning.
The researchers compared the echocardiography measures of current smokers against people who had never smoked, adjusting for age, sex, body mass index, hypertension, high cholesterol, diabetes and lung function.
Nearly 20% of the participants were current smokers, while roughly 40% were former smokers and 40% had never smoked.
Compared to people who had never smoked, the study found that current smokers had thicker, weaker and heavier hearts, and more pack-years were associated with the heart pumping less blood.
The researchers also found that current smoking and accumulated pack-years were associated with worsening of the structure and function of the left heart chamber, described as the most important part of the heart.
And they discovered that over a 10-year period, individuals 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.