Abstract
BACKGROUND: Whether smoking is associated with worse quality of life (QoL) or not is relatively controversial. The current study is to investigate the relationship between smoking and subjective QoL in a long cohort study. METHODS: The NIPPON DATA 90 project collected 8,383 community residents in 300 randomly selected areas as baseline data in 1990, administered four follow-up QoL surveys, and evaluated mortality statistics. We conducted multinomial logistic regression analysis to compare past smokers and current smokers to never smokers, with impaired QoL and mortality as outcomes. RESULTS: In four follow-ups, QoL data was collected from 2,035, 2,252, 2,522, and 3,280 participants in 1995, 2000, 2005, and 2012, respectively. In the 1995 follow-up, current smoking at baseline was not associated with worse QoL. In 2000 and 2005 follow-ups, smoking was significantly associated with worse QoL (odds ratio [OR] 2.1; 95% confidence interval [CI], 1.33-3.36 and OR 2.29; 95% CI, 1.38-3.80, respectively). In the 2012 follow-up, smoking was not associated with QoL. Sensitivity analysis did not change the result significantly. CONCLUSION: In this study we found that baseline smoking was associated with worse QoL in long-follow-up.