Impact of Smoking on Mortality in 80-Year-Old Japanese from the General Population

Abstract

Background: It is well known that cigarette smoking is the main health hazard in middle-aged people.However, data regarding smoking and health in old-aged people are limited, especially in the Japanese population. Objective: The present study aimed to investigate the influence of smoking on mortality in the elderly Japanese population. Methods: A cohort of 690 individuals of 80 years of age were categorized into 3 groups: non-smokers, ex-smokers and current smokers. The adjusted mortality after 4 years was compared among the 3 groups. The possible influence of smoking status on the cause of death was also investigated. Results: The overall mortality was significantly higher in males [relative risk (RR): 2.3, 95% confidence interval (CI): 1.0–5.2] and females (RR: 4.2, 95% CI: 1.9–9.5) in the current-smoker group than in the non-smoker group. The risk of any-cause mortality in the ex-smoker group was not statistically different from that in the non-smoker group. In males, current smokers died of cancer more frequently than non-smokers (RR: 10.7, 95% CI: 1.3–90.8). Cardiovascular disease was a significant cause of death in female current smokers (RR: 5.2, 95% CI: 1.6–16.9). This difference in mortality was not observed between groups of non-smokers and ex-smokers of both genders. In male smokers, there was a positive relationship between the daily amount of consumed cigarettes and overall mortality. Conclusion: Smokers should be encouraged to stop smoking, since habitual smoking increases the risk of mortality even in old age.

Smoking and mortality among persons aged 75–94

“…Our findings corroborate previous research (Doll et al, 2004; Fujisawa et al, 2008), generally associating increased mortality risk with higher daily smoking levels (Gellert et al, 2012). Investigating the role of current smoking levels, the cutoff point for increased mortality was 10 cigarettes.…”

“…Investigating the role of current smoking levels, the cutoff point for increased mortality was 10 cigarettes. This, in contrast to a cutoff of 5 found in a 25-year mortality follow-up of men aged 65–84 (Jacobs Jr et al, 1999), and of 20 found in a 4-year follow-up of Japanese persons aged 80 at baseline (Fujisawa et al, 2008). …”

The hazards and benefits associated with smoking and smoking cessation in Asia: a meta-analysis of prospective studies

“…In all, this gave 77 individual studies for inclusion in the meta-analysis: 73 cohort studies and four nested case-control studies. The characteristics of these studies are summarised in table 1, according to country and initial year of baseline survey 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74. Of the 77 studies, 42 studies were from Japan; 16 from China, five from Singapore, five from Taiwan, four from Korea, three from Hong Kong, one from India and one from Thailand.…”

Smoking After Age 65 Years and Mortality: The Kangwha Cohort Study

“…A study conducted in Hong Kong showed that current and former smokers are at increased risk of all-cause death, including both elderly male and female Chinese smokers 8 . Another recent study reported that habitual smoking contributes to higher mortality, even in an elderly Japanese population 16 . Several other studies that were conducted in Western countries also reported that smoking, even in elderly patients, is associated with all-cause mortality 9,10 .…”

“…It has been reported that habitual smoking is the single biggest risk factor associated with the development of CVD in females 7,16,17 . A Japanese study also reported that smoking in 80-year-old Japanese patients is more strongly associated with the risk of developing CVD in females than males 16 . Pope et al also suggested that the toxic effects of smoking on the coronary artery may be more evident in females than in males 18 .…”