Li Rulin, Luo Lanjun, Yuan Changwan, Zhu Qi
Key Laboratory of Digital-Intelligent Disease Surveillance and Health Governance, North Sichuan Medical College, Nanchong, China.
School of Management, North Sichuan Medical College, Nanchong, China.
J Glob Health. 2025 May 5;15:04150. doi: 10.7189/jogh.15.04150.
The prevalence of cognitive impairment among middle-aged and older adults remains high. While it has been proven that cigarette smoke exposure is associated with cognitive impairment, limited research has examined its relationship with the cognitive function trajectories of middle-aged and older adults.
We included data on 5084 middle-aged and older adults from the China Health and Retirement Longitudinal Study (CHARLS), version D, which covers the latest surveys from 2011 to 2018. In the CHARLS, cognitive function was measured by the Chinese version of the Mini-Mental State Examination (MMSE). Individuals exposed to cigarette smoke were categorised into four levels: non-smokers, second-hand smokers, former smokers, and current smokers. We used the latent growth mixture model (LGMM) to identify the potential heterogeneity of cognitive trajectories, and an unordered multilevel logistic regression to explore the relationship between baseline cigarette smoke exposure and cognitive function trajectories.
We identified three cognitive trajectory groups: slow decline group (6.2%), stable group (84.6%), and rapid decline group (9.1%). After controlling for other variables, we found that current smokers were 1.429 times more likely to develop into the rapid decline group than non-smokers (odds ratio (OR) = 1.429; 95% confidence interval (CI) = 1.086-1.881). As we continued to include demographic factors as covariates, currents smokers were 1.454 times more likely to develop into the rapid decline group than non-smokers (OR = 1.454; 95% CI = 1.052-2.01). After we included social activities, drinking and health factors as covariates, current smokers were 1.414 times more likely to develop into the rapid decline group than non-smokers (OR = 1.414; 95% CI = 1.015-1.97). This meant that current smoking remained an independent risk factor for decline trajectories, even after accounting for demographics, social activities, and health factors, suggesting that smoking has a robust association with functional or health decline.
The developmental trajectories of cognitive function among middle-aged and older adults are heterogeneous. We found that not smoking was a protective factor for cognitive function. This warrants further attention to the risk of cigarette smoking, which is a modifiable risk factor, and the subsequent adoption of interventions for smokers in order to slow down cognitive impairment and reduce its social and economic burden in the future.
中老年人群中认知障碍的患病率仍然很高。虽然已经证明接触香烟烟雾与认知障碍有关，但针对其与中老年人群认知功能轨迹之间关系的研究有限。
我们纳入了中国健康与养老追踪调查（CHARLS）D版中5084名中老年人群的数据，该版本涵盖了2011年至2018年的最新调查。在CHARLS中，认知功能通过中文版简易精神状态检查表（MMSE）进行测量。接触香烟烟雾的个体被分为四个级别：不吸烟者、二手吸烟者、既往吸烟者和当前吸烟者。我们使用潜在增长混合模型（LGMM）来识别认知轨迹的潜在异质性，并使用无序多水平逻辑回归来探讨基线香烟烟雾暴露与认知功能轨迹之间的关系。
我们识别出三个认知轨迹组：缓慢衰退组（6.2%）、稳定组（84.6%）和快速衰退组（9.1%）。在控制其他变量后，我们发现当前吸烟者发展为快速衰退组的可能性是非吸烟者的1.429倍（优势比（OR）=1.429；95%置信区间（CI）=1.086 - 1.881）。当我们继续将人口统计学因素作为协变量纳入时，当前吸烟者发展为快速衰退组的可能性是非吸烟者的1.454倍（OR = 1.454；95% CI = 1.052 - 2.01）。在我们将社交活动、饮酒和健康因素作为协变量纳入后，当前吸烟者发展为快速衰退组的可能性是非吸烟者的1.414倍（OR = 1.414；95% CI = 1.015 - 1.97）。这意味着即使在考虑了人口统计学、社交活动和健康因素之后，当前吸烟仍然是衰退轨迹的一个独立危险因素，表明吸烟与功能或健康衰退存在密切关联。
中老年人群认知功能的发展轨迹是异质性的。我们发现不吸烟是认知功能的一个保护因素。这值得进一步关注吸烟这一可改变的危险因素的风险，并随后对吸烟者采取干预措施，以便在未来减缓认知障碍并减轻其社会和经济负担。
