Division of Clinical Epidemiology and Aging Research, German Cancer Research Center (DKFZ), Im Neuenheimer Feld 581, 69120, Heidelberg, Germany,
Eur J Epidemiol. 2013 Oct;28(10):823-31. doi: 10.1007/s10654-013-9840-9. Epub 2013 Aug 30.
To examine potential associations of the history of lifetime smoking and smoking cessation with cognitive function in the elderly. In a population-based cohort study of older adults in Saarland, Germany, a detailed lifetime history of smoking was obtained using standardised questionnaires. Cognitive function was assessed with a validated telephone-based instrument (COGTEL) at the five-year follow-up in a subsample of n = 1,697 participants with a baseline age >65 years. Multiple linear regression models were employed to predict cognitive performance, adjusting for potential confounding factors. Ever-smokers with a higher cumulative dose of smoking in pack-years scored lower in the cognitive assessment than never-smokers, with the association being more pronounced in current smokers than in former smokers. In fully adjusted models, current smokers with 21-40 pack-years scored 4.06 points lower (95 % CI -7.18 to -0.94) than never-smokers. In former smokers, a longer time since smoking cessation was associated with higher scores in the cognitive test with reference to current smokers, even after adjustment for pack-years. Former smokers who had quit for more than 30 years scored 4.23 points higher (95 % CI 1.75 to 6.71) than current smokers. Dose-response-relationships of cognitive function with cumulative dose of smoking as well as with time since smoking cessation were substantiated by restricted cubic splines regression. Our results support suggestions that smokers are at an increased risk for cognitive impairment in older age; that the risk increases with duration and intensity of smoking, and subsides with time after smoking cessation.
为了研究终生吸烟史和戒烟与老年人认知功能之间的潜在关联。在德国萨尔州一项基于人群的老年人大队列研究中，使用标准化问卷获得了详细的终生吸烟史。在 n=1697 名基线年龄大于 65 岁的参与者的亚组中，使用经过验证的基于电话的认知测试（COGTEL）在五年随访时评估认知功能。采用多元线性回归模型，根据潜在的混杂因素调整，预测认知表现。与从不吸烟者相比，有更高累计吸烟包年数的现吸烟者和曾经吸烟者在认知评估中得分较低，而当前吸烟者的相关性比曾经吸烟者更为显著。在完全调整的模型中，有 21-40 包年吸烟史的当前吸烟者比从不吸烟者的认知测试得分低 4.06 分（95%CI -7.18 至 -0.94）。对于曾经吸烟者，与当前吸烟者相比，戒烟时间越长，认知测试得分越高，即使调整了吸烟包年数。与当前吸烟者相比，戒烟超过 30 年的曾经吸烟者的认知测试得分高 4.23 分（95%CI 1.75 至 6.71）。使用限制性立方样条回归证实了认知功能与累积吸烟剂量以及戒烟后时间之间的剂量反应关系。我们的研究结果支持这样的观点，即吸烟者在老年时认知障碍的风险增加；风险随着吸烟时间和强度的增加而增加，并随着戒烟后时间的推移而减少。
