Yang Yong, Jiang Yu
School of Public Health, University of Memphis, Memphis, Tennessee, USA.
Innov Aging. 2024 Oct 3;8(10):igae093. doi: 10.1093/geroni/igae093. eCollection 2024.
Older adults are vulnerable to social isolation, making it crucial to understand its impact on dementia risk. Yet, existing evidence lacks consistency, with studies using varied measures of social isolation and overlooking potential confounders. We aim to investigate the associations between social isolation and dementia risk among older adults, hypothesizing that this association may diminish after adjusting for confounding factors.
We used 2 977 community-dwelling older adults who had no dementia in 2015 from National Health and Aging Trends. Group-based trajectory modeling was used to analyze the trajectories of social isolation, depression, and anxiety from 2011 to 2015. Cox proportional hazards regression models were then employed to estimate the association between social isolation trajectories and incident dementia from 2015 to 2022, adjusting for demographic variables, depression, anxiety, self-rated health, smoking status, and cardiovascular disease-related variables.
Three social isolation trajectories were identified: minimal, moderate, and high levels of social isolation. During a mean follow-up of 3.6 years, 19.0% of participants were diagnosed with dementia. When only demographics were adjusted, individuals in the moderate social isolation group were 22% less likely to develop dementia compared to those with high social isolation. This association between social isolation and incident dementia became nonsignificant after further adjustment for depression, anxiety, and health indicators.
The association between social isolation and dementia risk may be mediated by factors such as depression and other health indicators.
老年人易受社会隔离影响，因此了解其对痴呆风险的影响至关重要。然而，现有证据缺乏一致性，各研究对社会隔离的衡量方法各异，且忽视了潜在的混杂因素。我们旨在调查老年人中社会隔离与痴呆风险之间的关联，假设在调整混杂因素后这种关联可能会减弱。
我们使用了来自《国家健康与老龄化趋势》的2977名2015年时无痴呆的社区居住老年人。基于群组的轨迹模型用于分析2011年至2015年期间社会隔离、抑郁和焦虑的轨迹。然后采用Cox比例风险回归模型来估计2015年至2022年期间社会隔离轨迹与新发痴呆之间的关联，并对人口统计学变量、抑郁、焦虑、自评健康、吸烟状况和心血管疾病相关变量进行了调整。
确定了三种社会隔离轨迹：低水平、中等水平和高水平社会隔离。在平均3.6年的随访期间，19.0%的参与者被诊断患有痴呆。仅调整人口统计学因素时，与高水平社会隔离者相比，中等社会隔离组的个体患痴呆的可能性低22%。在进一步调整抑郁、焦虑和健康指标后，社会隔离与新发痴呆之间的这种关联变得不显著。
社会隔离与痴呆风险之间的关联可能由抑郁和其他健康指标等因素介导。
