Why Heart Transplant Patients Resume Smoking Revealed in University of Pittsburgh Study Presented at International Heart and Lung Transplant Meeting
PITTSBURGH, April 11, 2002 — Nearly half of ex-smokers who receive heart transplants resume smoking at some point after their life-saving operation, and now researchers have good evidence to suggest who is at risk of relapse. Results of a University of Pittsburgh study presented at the 22nd Annual Meeting and Scientific Sessions of the International Society for Heart and Lung Transplantation outline for the first time the strongest predictors for smoking relapse in heart transplant patients.
Leading the list: a short abstinence period before transplantation, bouts of depression or anxiety within a few months of the transplant and a caregiver who smokes.
"Understanding which patients go back to smoking should help us design more effective intervention strategies to aggressively target high risk patients as well as their caregivers," reported Carol Stilley, Ph.D., assistant professor of nursing and psychiatry, University of Pittsburgh schools of Nursing and Medicine.
"Among the general population, about 90 percent of those who try to quit will relapse within a year, so in many ways our transplant patients are showing much greater willpower. Yet the detrimental effects of smoking depend on how much and for how long someone smoked, and in an immunosuppressed patient, these detrimental effects are likely to be much greater," added Mary Amanda Dew, Ph.D., professor of psychiatry, psychology and epidemiology, and the study director.
Drugs that transplant patients take to prevent organ rejection suppress their immune systems, making these patients more susceptible to infections and cancers. A smoking history and relapse to smoking could very well compound cancer risks for transplant patients. Indeed, in recent years, transplant teams have seen more of their heart transplant patients develop inoperable lung tumors -- all previous smokers -- four to five years after their transplants. Smoking reduces survival; studies conducted in Europe have indicated a 37 percent five-year survival rate for heart transplant patients who smoke, compared to an 80 percent survival for their nonsmoking counterparts.
The Pitt researchers studied 202 heart transplant recipients for up to three years. Of these, 144 (71 percent) had a history of smoking, from two to more than 95 pack years, a calculation based on the number of packs per day times the number of years smoked. As part of a longitudinal study about health habits following transplantation, the researchers conducted in-depth interviews with the patients, their family caregivers, and the patients' transplant nurse coordinators at two, seven, 12 and 36 months after transplantation.
Fifty-five recipients (27 percent of the sample of 202 participants) started smoking at some point after their transplant, and of these recipients, 45 (82 percent) started smoking within the first year, including 26 (58 percent) who started within two months. One patient who had not previously been a smoker took up smoking an occasional cigar. Throughout the three-year period, 25 smoked 10 or fewer cigarettes a day, nine smoked between 11 and 19 a day, and four smoked a pack or more daily. Amount was unknown for the remaining 11 who were mostly cigar smokers.
Based on the series of interviews, researchers were also able to perform statistical analyses indicating the strongest predictors to smoking relapse. Patients who quit smoking for a period of less than six months before their transplant (as opposed to those who quit for longer periods of time) were much more likely to start smoking earlier and more often. Depression and anxiety within two months after the transplant also made it more likely that relapse would occur early, and these patients reported smoking the most -- more than a half a pack a day.
Having a caregiver who smokes was less significant but remained a strong predictor, say the researchers. Of 194 caregivers who took part in the study, 50 were smokers. Of the 55 recipients who smoked, 21 had a smoking caregiver.