目標：本研究應用失能形成進程模式，探討中老年人不同吸、戒菸行為對失能情形之影響，以進一步了解生活型態中的風險因子-吸菸與身體活動功能間的關聯。方法：採縱貫性研究設計，使用『台灣地區中老年身心社會生活狀況長期追蹤調查』1989~2007年共計6波之調查資料，以50歲以上且調查基期時未失能之中老年人為研究對象；並以邏輯斯迴歸及Cox's比例風險模式分析校正人口學特質及健康狀況等背景變項後，吸、戒菸行為對中老年人失能之影響。結果：控制相關影響因素後，吸菸者之失能風險顯著較未吸菸者高，但已戒菸者之失能風險則與未吸菸者無顯著差異；吸菸年數亦與失能有關；而戒菸部分，在60歲前戒菸與戒菸年數大於15年者，其失能風險皆與未吸菸者無顯著差異。結論：中老年人不同之吸、戒菸行為對失能情形有不同之影響，故菸害防制相關政策除勸導大眾勿吸菸外，亦應鼓勵吸菸者儘早戒菸。

Objectives: To determine whether or not different smoking behavior would have different effects on the elderly, we used the disablement process model to examine the associations between smoking, smoking cessation, and physical functional disability among middle-aged and elderly persons. Methods: This study was based on a longitudinal study design, applying data obtained from the ＂Survey of Health and Living Status of Middle Aged and Elders in Taiwan,＂ which had been conducted in 1989, 1993, 1996, 1999, 2003, and 2007 by the Health Promotion Administration of the Ministry of Health and Welfare. The study populations were middle-aged and elderly persons ＞ 50 years of age, and physically functional independent in Taiwan. Logistic regression and Cox's proportional hazards model were performed to examine the relationship between the independent and dependent variables after controlling for confounding factors. Results: There was a positive association between smoking, smoking cessation, and physical functional disability among middle-aged and elderly persons. Smokers had higher risks of physical functional disability than never-smokers after controlling for other factors. There were no significant differences on physical functional disability between former smokers and neversmokers. Whether former smokers or smokers, a longer duration of smoking was associated with poorer physical performance. No significant differences existed between former smokers who had quit smoking ＞ 15 years, former smokers who had quit smoking under 60 years of age, and neversmokers. Conclusions: Different smoking status and different smoking cessation behavior leads to different effects on physical performance. Based on the results of this study we suggest that the Health Promotion Administration of the Ministry of Health and Welfare should recommend people not to smoke, encourage smokers to quit smoking as soon as possible, and be committed to promoting a smoke-free environment.