Department of Neurology, Beth Israel Deaconess Medical Center (BIDMC), Harvard Medical School Boston (HMS), Boston, Massachusetts, United States of America.
Translational Research Center for TBI and Stress Disorders (TRACTS) and Geriatric Research Educational and Clinical Research Center (GRECC) VA Boston Healthcare System, Boston, Massachusetts, United States of America.
PLoS One. 2022 Nov 29;17(11):e0278319. doi: 10.1371/journal.pone.0278319. eCollection 2022.
Maintaining independence in older age is an important aspect of quality of life. We investigated depressive symptoms as an important modifiable risk factor that may mediate the effects of physical and cognitive decline on disability.
We prospectively analyzed data from 223 adults (age 50-85; 117 controls and 106 with type-2 diabetes) over 48 weeks who were participating in a clinical trial "Memory Advancement by Intranasal Insulin in Type 2 Diabetes." Data from self-reported disability (World Health Organization Disability Assessment Schedule) and depressive symptoms (Geriatric Depression Scale) were obtained from baseline, week 25, and week 48 visits. Cognition (Mini-mental status examination) and medical comorbidities (Charlson Comorbidity Index) were assessed at baseline. Longitudinal analysis assessed the extent to which change in depressive symptoms predicted worsening disability. Mediation analyses were performed to determine the extent to which depressive symptoms accounted for disability associated with worse cognition, walking speed, and comorbidities.
At baseline, depressive symptoms, cognition, and walking speed were within normal limits, but participants had a high 10-year risk of cardiovascular mortality. Depressive symptoms were related to disability at baseline (p<0.001), and longitudinally (p<0.001). Cognition, walking speed, and comorbidities were associated with disability at baseline (p-values = 0.027-0.001). Depressive symptoms had a large mediating effect on disability longitudinally: the indirect effect on disability via depression accounts for 51% of the effect of cognition, 34% of the effect of mobility, and 24% of the effect of comorbidities.
Depressive symptoms substantially exacerbated the effects of worsening cognition, gait speed, and comorbidities on disability. In our sample, most individuals scored within the "normal" range of the Geriatric Depression Scale, suggesting that even subclinical symptoms can lead to disability. Treating subclinical depression, which may be under-recognized in older adults, should be a public health priority to help preserve independence with aging.
在老年时保持独立是生活质量的一个重要方面。我们研究了抑郁症状，作为一个重要的可改变的风险因素，它可能会调节身体和认知能力下降对残疾的影响。
我们对参加一项名为“2 型糖尿病患者经鼻内胰岛素促进记忆”的临床试验的 223 名成年人（年龄 50-85 岁；117 名对照组和 106 名 2 型糖尿病患者）进行了前瞻性分析，随访时间为 48 周。从基线、第 25 周和第 48 周的就诊中获得自我报告的残疾（世界卫生组织残疾评估量表）和抑郁症状（老年抑郁量表）的数据。在基线时评估认知（简易精神状态检查）和医疗合并症（Charlson 合并症指数）。纵向分析评估了抑郁症状变化在多大程度上预测残疾恶化。进行中介分析以确定抑郁症状在多大程度上解释了与认知能力下降、行走速度和合并症相关的残疾。
在基线时，抑郁症状、认知和行走速度均在正常范围内，但参与者的心血管死亡率在 10 年内的风险较高。抑郁症状与基线时的残疾有关（p<0.001），且具有纵向相关性（p<0.001）。认知、行走速度和合并症与基线时的残疾有关（p 值=0.027-0.001）。抑郁症状对残疾的纵向影响具有较大的中介作用：抑郁对残疾的间接影响占认知影响的 51%，占移动性影响的 34%，占合并症影响的 24%。
抑郁症状大大加剧了认知能力下降、步态速度和合并症对残疾的影响。在我们的样本中，大多数人在老年抑郁量表的“正常”范围内评分，这表明即使是亚临床症状也会导致残疾。治疗亚临床抑郁症，这在老年人中可能被低估，应该是公共卫生的一个优先事项，以帮助保持随着年龄增长的独立性。
