Meng Xiangfei, D'Arcy Carl
Department of Psychiatry, College of Medicine, University of Saskatchewan, Saskatoon, Canada.
Asia Pac Psychiatry. 2013 Sep;5(3):175-82. doi: 10.1111/j.1758-5872.2012.00222.x. Epub 2012 Aug 6.
Although cognitive impairment is widely accepted as a leading indicator of dementia, influences of cognitive status on incident dementia and mortality remain unclear. The present study investigated the morbidity hazard associated with cognitive impairment and the mortality hazard associated with dementia in comparison to cognitively intact seniors.
A population-based sample of 2914 seniors with clinically diagnosed cognitive status at Wave I (1991-1992) of the Canadian Study of Health and Aging (CSHA) were followed-up 5 years later (1996-1997). At Wave I, there were 921 cognitively intact, 861 cognitively impaired but not demented (CIND), and 1132 seniors with dementia, respectively. The primary outcome measures 5 years later were being cognitively intact, CIND, dementia and death. Kaplan-Meier estimates, log-rank tests, and Cox's proportional models were used in the analyses.
Respondents with CIND at Wave I were 2.191 times (95%CI 1.706-2.814) more likely to have dementia 5 years later than cognitively intact seniors. After adjusting for confounding socio-demographic and health status factors, the odds ratio was reduced to 2.147 times (95%CI 1.662-2.774), but remained significant. Respondents with CIND had a mortality rate 1.869 times (95%CI 1.602-2.179) and seniors with dementia 3.362 times greater (95%CI 2.929-3.860) than that of seniors who were cognitively intact. After controlling the confounders, the odds remained significant at 1.576 (95%CI 1.348-1.843) for CIND respondents and 2.415 (95%CI 2.083-2.800) for seniors with dementia.
CIND increases both the risk of dementia and mortality. Early intervention with CIND is warranted to reduce both dementia incidence and mortality.
尽管认知障碍被广泛认为是痴呆症的主要指标，但认知状态对痴呆症发病率和死亡率的影响仍不明确。本研究调查了与认知障碍相关的发病风险以及与痴呆症相关的死亡风险，并与认知功能正常的老年人进行了比较。
以加拿大健康与老龄化研究（CSHA）第一波（1991 - 1992年）临床诊断的认知状态为基础，选取了2914名老年人作为样本，并在5年后（1996 - 1997年）进行随访。在第一波时，分别有921名认知功能正常、861名认知障碍但未患痴呆症（CIND）以及1132名患有痴呆症的老年人。5年后的主要结局指标为认知功能正常、CIND、痴呆症和死亡。分析中使用了Kaplan - Meier估计、对数秩检验和Cox比例模型。
第一波时患有CIND的受访者在5年后患痴呆症的可能性是认知功能正常老年人的2.19倍（95%CI 1.706 - 2.814）。在调整了社会人口统计学和健康状况等混杂因素后，优势比降至2.147倍（95%CI 1.662 - 2.774），但仍具有显著性。患有CIND的受访者死亡率是认知功能正常老年人的1.869倍（95%CI 1.602 - 2.179），患有痴呆症的老年人死亡率是认知功能正常老年人的3.362倍（95%CI 2.929 - 3.860）。在控制混杂因素后，CIND受访者的优势比仍显著为1.576（95%CI 1.348 - 1.843），患有痴呆症的老年人的优势比为2.415（95%CI 2.083 - 2.800）。
CIND会增加患痴呆症和死亡的风险。有必要对CIND进行早期干预，以降低痴呆症发病率和死亡率。
