School of Public Health and Management, Chongqing Medical University, Chongqing, China.
Research Center for Medicine and Social Development, Chongqing Medical University, Chongqing, China.
Front Public Health. 2023 May 3;11:1165753. doi: 10.3389/fpubh.2023.1165753. eCollection 2023.
The association between the instrumental activities of daily living (IADL) score and the risk of initial cognitive function impairment is inconclusive. We aimed to identify distinctive IADL trajectories and examine their relationship with the onset of mild cognitive impairment (MCI) among Chinese older people.
The study used six-wave longitudinal data from the Chinese Longitudinal Healthy Longevity Survey conducted between 2002 and 2018. It included a total of 11,044 Chinese people aged 65 years or older. A group-based trajectory model was used to identify distinctive trajectories of the IADL score, and the Cox proportional hazards model was used to explore the hazard ratio of various trajectories at the onset of MCI. Interaction analysis was used to analyze individual modification between the IADL trajectories and the onset of MCI. Finally, we adopted four types of sensitivity analysis to verify the robustness of the results.
During a median follow-up of 16 years, the incidence of MCI was 6.29 cases per 1,000 person-years (95% confidence interval [CI] 5.92-6.68). Three distinct IADL trajectory groups were identified: a low-risk IADL group (41.4%), an IADL group with increasing risk (28.5%), and a high-risk IADL group (30.4%). Using the Cox proportional hazards model after adjusting for covariates, we found that compared with the low risk IADL group, the hazard ratio of the IADL group with increasing risk was 4.49 (95% CI = 3.82-5.28), whereas that of the high-risk IADL group was 2.52 (95% CI 2.08-3.05). Treating the IADL group with increasing risk as the reference, the hazard ratio for the high-risk IADL group was 0.56 (95% CI 0.48-0.66). Interaction analyses showed that age and residence were significant moderators ( for interaction <0.05).
A group-based trajectory model was developed to classify older people into three distinct trajectory groups of the IADL score. The IADL group with increasing risk had a greater risk of MCI than the high-risk IADL group. In the IADL group with increasing risk, city residents of ≥80 years were the most likely to develop MCI.
工具性日常生活活动（IADL）评分与初始认知功能障碍风险之间的关联尚无定论。我们旨在确定独特的 IADL 轨迹，并研究它们与中国老年人轻度认知障碍（MCI）发病的关系。
本研究使用了 2002 年至 2018 年期间进行的中国长寿纵向研究的六波纵向数据。它包括 11044 名 65 岁或以上的中国人。采用基于群组的轨迹模型来识别 IADL 评分的独特轨迹，并采用 Cox 比例风险模型来探讨各种轨迹在 MCI 发病时的风险比。采用交互分析来分析 IADL 轨迹与 MCI 发病之间的个体修饰作用。最后，我们采用了四种类型的敏感性分析来验证结果的稳健性。
在中位数为 16 年的随访期间，MCI 的发病率为每 1000 人年 6.29 例（95%置信区间 [CI] 5.92-6.68）。确定了三个不同的 IADL 轨迹组：低风险 IADL 组（41.4%）、IADL 风险增加组（28.5%）和高风险 IADL 组（30.4%）。在调整了协变量后，使用 Cox 比例风险模型，我们发现与低风险 IADL 组相比，IADL 风险增加组的风险比为 4.49（95%CI=3.82-5.28），而高风险 IADL 组的风险比为 2.52（95%CI 2.08-3.05）。以 IADL 风险增加组为参照，高风险 IADL 组的风险比为 0.56（95%CI 0.48-0.66）。交互分析表明，年龄和居住地是显著的调节因素（<0.05）。
采用基于群组的轨迹模型将老年人分为三个不同的 IADL 评分轨迹组。IADL 风险增加组发生 MCI 的风险高于高风险 IADL 组。在 IADL 风险增加组中，≥80 岁的城市居民最有可能发生 MCI。
