Study IDs Patients Most Likely to Quit Smoking After ASCVD Event

Fewer than one in five patients quit smoking after an atherosclerotic cardiovascular disease (ASCVD) event, but more serious events tended to track with an increased rate of cessation, according to a large registry study.

Both the negative effects of smoking and the profound benefits of smoking cessation are widely recognized by cardiologists and patients alike, yet event rates remain high for those who don’t stop.

“Smoking is such an addictive process that's just hard to get people to quit smoking,” lead author Vittal Hejjaji, MD, MSc (Saint Luke’s Mid America Heart Institute, Kansas City, MO), told TCTMD. “If they have gotten to the point where they have gotten some form of cardiac event, that probably means that they have been smoking for many, many years. And our efforts to get them to quit smoking have been so futile for so many years that I think the healthcare community in general, including myself, have just been so frustrated. So we oftentimes kind of gloss over that.”

To optimally focus cessation efforts and resources, Hejjaji told TCTMD, his team set out to conduct research “to find the sweet spot of when patients have an inclination toward quitting,” he said.

Their study, published online last week in Circulation: Cardiovascular Quality and Outcomes, included 1,933,283 patients (mean age 62 years; 54.4% men) from the National Cardiovascular Data Registry Practice Innovation and Clinical Excellence outpatient cardiac registry who identified as current smokers between 2013 and 2018.

Over the study period, 322,743 patients had an interim ASCVD event and were still smoking, but only 12.8% had quit by their first subsequent clinic visit. This rate was higher among the 49.8% of patients with baseline ASCVD compared with those without (13.4% vs 11.5%).

The seriousness of the event was directly linked to an increased likelihood of reporting smoking cessation. For example, patients who were most likely to quit included those who had an MI, underwent CABG, or had a stroke or TIA. Those least likely to quit underwent elective PCI or had a new diagnosis of peripheral artery disease.

Association Between ASCVD Event and Smoking Cessation

Hejjaji guessed that increased rates of cessation were observed following CABG compared with a procedure like PCI because the latter is “less intense for the patient.” Since quitting smoking can really be a mental game for people, it makes sense that the impact of the medical intervention would play a role, he said.

He also acknowledged the potential for errors in the study, especially given that the smoking cessation rates were self-reported. “It could be that they may have quit, but if the doctor just did not ask if they quit smoking or if they did not mark it in the EMR, we don't see it,” Hejjaji said. Even so, he guessed, it’s not likely that the quit rate is much higher than 20%, as identified in other similar studies.

Ultimately, these findings are mostly “exploratory,” according to Hejjaji. “For example, if I see a patient who just had a bypass surgery, our data shows that this person is way more likely to quit smoking,” he said. “If I had something like a smoking cessation clinic that can bring down all the resources that are available to help [patients] quit smoking and they can take only five patients, I would send my post-CABG patients as compared to [others]. Of course, I would want all my patients to go there, but if I had to focus resources in one area, our study shows that at least start with the people who are more likely to quit.”