Smoking E-Cigarette Increased Risk of Heart Attacks and Strokes

Swedish scientists speaking at the European Respiratory Society International Congress in Milan, Italy, say that they have demonstrated for the first time that e-cigarettes with nicotine cause arteries in humans to stiffen, thus increasing the risk of heart attacks and strokes in later life.

“The number of e-cigarette users has increased dramatically in the last few years. E-cigarettes are regarded by the general public as almost harmless,” said Magnus Lundbäck, M.D., Ph.D., who is a research leader and clinical registrar at the Danderyd University Hospital, Karolinska Institute, in Stockholm, Sweden. “The e-cigarette industry markets their product as a way to reduce harm and to help people to stop smoking tobacco cigarettes. However, the safety of e-cigarettes is debated, and a growing body of evidence is suggesting several adverse health effects.

“The results are preliminary, but in this study we found there was a significant increase in heart rate and blood pressure in the volunteers who were exposed to e-cigarettes containing nicotine. Arterial stiffness increased around three-fold in those who were exposed to nicotine containing e-cigarettes compared to the nicotine-free group.”

Dr. Lundbäck and his colleagues recruited 15 young, healthy volunteers to take part in the study last year. The volunteers were infrequent smokers (a maximum of ten cigarettes a month) and they had not used e-cigarettes before the study. The average age was 26, and 59% were female, 41% male. They were randomized to use e-cigarettes with nicotine for 30 minutes on one of the study days and e-cigarettes without nicotine on the other day. The researchers measured blood pressure, heart rate, and arterial stiffness immediately after smoking the e-cigarettes and then two and four hours later.

In the first 30 minutes after smoking e-cigarettes, there was a significant increase in blood pressure, heart rate, and arterial stiffness. No such effect was seen on heart rate or arterial stiffness in the volunteers who had smoked e-cigarettes without nicotine.

“The immediate increase in arterial stiffness that we saw is most likely attributed to nicotine,” noted Dr. Lundbäck. “The increase was temporary. However, the same temporary effects on arterial stiffness have also been demonstrated following use of conventional cigarettes. Chronic exposure to both active and passive cigarette smoking causes a permanent increase in arterial stiffness. Therefore, we speculate that chronic exposure to e-cigarettes with nicotine may cause permanent effects on arterial stiffness in the long term. As of today, there are no studies on the long-term effects of arterial stiffness following chronic e-cigarette exposure.

“It is very important that the results of this and other studies reach the general public and the healthcare professionals working in preventive healthcare, for example in smoking cessation. Our results underline the necessity of maintaining a critical and cautious attitude towards e-cigarettes, especially for healthcare professionals. E-cigarette users should be aware of the potential dangers of this product, so that they can decide whether to continue or quit based on scientific facts.”