[Smoking and survival in centenarians]

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 disease, and disability as well as adding to an increase in mortality rate. In order to verify if a healthy lifestyle really favours 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 as regards residual survival and health conditions. Our sample consists of 157 centenarians selected among the registered residents of Rome: 39 males and 118 females (ratio = 1:3), mean age being 101.59 years (sd = 1.8). 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 was 21.2 years while the average age of quitting in former smokers was 65.7 years with an average of 44.7 smoking years (sd = 17.1). The average number of smoked cigarettes per day is quite low, less than 10 cigarettes. There seemed to be a significant difference (p < 0.001) in gender results in smokers: male centenarians were 46%, while female reached only 8.1%. Statistically significant higher prevalence of diseases 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 than in non-smokers. In conclusion, our study is evidence that smoking is for all, but some exceptional subjects, incompatible with successful aging and compromises life expectancy even in extreme longevity.