Smoking and longevity: an incompatible binomial?

Abstract

In Western countries data from clinical and epidemiological studies have induced the public health offices to promote a great deal of advertising and informative campaigning for smoking reduction. Cigarette smoking has been clearly linked to the most common causes of death in the elderly and contributes to the higher death rate and disability rate associated with many chronic illnesses that are common in this age group. The combination of smoking along with other risk factors like hypertension and diabetes increase high frequency diseases, disability as well as adding to an increase in mortality rate. In order to verify if a healthy lifestyle really favors longevity and how much smoking is incompatible with extreme longevity we investigated the prevalence of smokers and the total smoking exposure of a sample of centenarians in relation with residual survival and health conditions. Our sample consists of 157 centenarians living in Rome, 39 males and 118 females (ratio m/f =1:3),mean age being 101.59 +/- 1.8 years (+/-SD), 83.8% of the centenarians have never smoked,13.5 % are former smokers, and 2.7% are active smokers. The average starting age of smoking is 21.2 years, while the average age of quitting is 65.7 years with an average of 44.7 +/- 17.1 smoking years. The average number of smoked cigarettes per day is quite low,less than 10 cigarettes, so that the total average number of smoked cigarettes is 158,045,well under 280,000 which is considered the cut-off point in many studies of when tumors are noticed. There seemed to be a significant difference (p < 0.001) in gender results in smokers: among male centenarians smokers reached 46%, while female smoker centenarians reached only 8.1%. Statistically significant chronic illnesses were noted among centenarian smokers over the age of 65 (p < 0.02). Moreover, Cox's regression has shown in centenarians a lower survival rate (p < 0.05) in smokers (20.7 +/- 11.2 months) than in non-smokers (27.0 +/- 19.0 months). In conclusion, our study evidences that smoking is for all but some exceptional subjects, incompatible with successful aging and compromises life expectancy even in extreme longevity.