30- YEAR STUDY OF PCI PATIENTS SHOW THOSE THAT QUIT SMOKING LIVE LONGER THAN THOSE WHO CONTINUE TO SMOKE AND LONG-TERM ALL-CAUSE MORTALITY RATES OF QUITTERS ARE SIMILAR IN THE END TO THOSE OF NONSMOKERS

A 30-year study of patients who underwent successful percutaneous coronary intervention (PCI) shows that those who quit smoking appear to live longer than those who continue to smoke, according to a study published online July 29, 2013, ahead of print in the American Journal of Cardiology. Furthermore, long-term all-cause mortality rates of quitters are similar in the end to those of nonsmokers.

Investigators led by Ron T. van Domburg, PhD, of Erasmus Medical Center (Rotterdam, The Netherlands), analyzed life expectancy for 856 consecutive patients who underwent PCI between 1980 and 1985 and for whom 30-year follow-up data, including self-reported smoking status at 1 year, were available. Patients were divided into 3 groups:

• Nonsmokers
• Quitters
• Persistent smokers

Quitters Win in the End:

Overall, there were 14,977 patient-years of follow-up (median 19.5 years). The self-reported smoking rate fell from 61% prior to PCI to 36% at 1 year.

The cumulative 30-year survival rate was higher among those who quit smoking, as was life expectancy, which showed a 2-year advantage for quitters (table 1).

Table 1. Survival and Life Expectancy:

	Persistent Smokers (n = 287)	Quitters (n = 210)	P Value
30-Year Survival	14%	29%	0.005
Life Expectancy, years	16.4	18.5	< 0.0001

Quitters had similar all-cause mortality rates compared with nonsmokers, and both of these groups had lower mortality than persistent smokers (adjusted HR 0.57; 95% CI 0.46-0.71 and adjusted HR 0.42; 95% CI 0.34-0.52, respectively).

Other independent predictors of long-term all-cause mortality were:

• Multivessel disease (adjusted HR 1.45; 95% CI 1.19-1.75)
• Previous MI (adjusted HR 1.27; 95% CI 1.06-1.53)
• Hypertension (adjusted HR 1.37; 95% CI 1.14-1.64)

Dated Yet Relevant:

According to the study authors, although all the PCI procedures were performed in the pre-stent era, the findings are in agreement with prior research showing substantial reductions in all-cause mortality and nonfatal myocardial reinfarctions with smoking cessation in patients with coronary heart disease.

“Although it remains to be seen to what extent smoking cessation will benefit current patients, there are no indications that the unfavorable effect of smoking can be made undone using novel treatment methods,” they write. “In addition, it has been shown that stent placement compared with balloon angioplasty benefits only on target vessel revascularization, not mortality.”

The authors acknowledge, however, that complete information was not obtained in all patients. Additional limitations include the reliance on self-reported smoking data and the capturing of information at only 1 year post-PCI and no further, they note.

Importance of Natural History:

In a telephone interview with TCTMD, Ajay J. Kirtane, MD, SM, of Columbia University Medical Center (New York, NY), said longitudinal studies such as this one are important because “so much of what we do is based upon 30-day, and 1-year outcomes. Even the COURAGE trial was only 4.6 years of follow up, so it’s really important to look at longer data . . . because in some respect they represent actuarial tables that show us the natural history of these patients.”

Additionally, he said it reaffirms that patients can reverse some of the smoking-related damage by quitting.

“So many times you talk with patients and they think that because they’ve been smoking so long there is nothing they can do,” Dr. Kirtane said. “But data like these reiterate the fact that probably for all but the heaviest of smokers, stopping can drop you back down to a baseline risk equivalent with people who never smoked. That gives patients hope and it’s important.”

He said the data are “one more thing in my toolbox to convince patients they should stop smoking.”

Quoting Old Data Not Justifiable:

But Morton J. Kern, MD, of the University of California, Irvine (Irvine, CA), told TCTMD in a telephone interview that while hard data showing survival advantages of quitting are helpful, getting patients to make a life change is far more complicated.

“The more ammunition you have, the better. But honestly, most people are not swayed by these kind of data,” he commented. “You can tell them [smoking] is one of the highest risk factors for stent thrombosis, restenosis, etcetera. After they have had a heart attack, it’s a little easier to convince them because they’re scared and sometimes they do need that wake-up call. But if they are not hurting enough or sick enough, it’s tough.”

Dr. Kern said he typically speaks with the family about the importance of quitting as a way of invoking “peer pressure.”

He dismissed the importance of the study data, however, saying it is “ludicrous” to try to generalize pre-stent PCI outcomes to a modern population. “Stents changed the landscape of PCI and in the pre-stent era, all of the outcomes are totally different from what we see today,” Dr. Kern said. “I don’t see how you can justify quoting from data that are this old.”

Study Details:

All PCI procedures were performed with balloon angioplasty only. The mean age of the patients was 56.2 years, and most (80%) were men.

POSTED BY:  Steven Almany M.D.