Aerts Liesbeth, Heffernan Megan, Kochan Nicole A, Crawford John D, Draper Brian, Trollor Julian N, Sachdev Perminder S, Brodaty Henry
From the Dementia Collaborative Research Centre Network (L.A., M.H., H.B.), Centre for Healthy Brain Ageing (J.D.C., N.A.K., B.D., J.N.T., P.S.S., H.B.), and Department of Developmental Disability Neuropsychiatry (J.N.T.), School of Psychiatry, University of New South Wales; and Neuropsychiatric Institute (N.A.K., P.S.S.) and Academic Department for Old Age Psychiatry (B.D., H.B.), Prince of Wales Hospital, Randwick, Australia.
Neurology. 2017 Jun 6;88(23):2225-2232. doi: 10.1212/WNL.0000000000004015. Epub 2017 May 10.
We sought to understand the trajectory of mild cognitive impairment (MCI) better by examining longitudinally different MCI subtypes and progression to dementia and reversion to normal cognition in a community sample.
We evaluated the stability of MCI subtypes and risk of dementia over 4 biennial assessments as part of an ongoing prospective cohort study, the Sydney Memory and Ageing Study.
While prevalence of MCI and different MCI subtypes remains relatively stable across all assessments, reversion from MCI and transitions between different MCI subtypes were common. Up to 46.5% of participants classified with MCI at baseline reverted at some point during follow-up. The majority (83.8%) of participants with incident dementia were diagnosed with MCI 2 years prior to their dementia diagnosis. Both reverters and participants with stable MCI were at an increased risk of progression to dementia compared to those without MCI at baseline (HR 6.4, = 0.02, and HR 24.7, < 0.001, respectively); however, the risk of dementia in participants with MCI who did not revert was higher than in reverters (HR 2.5, = 0.01). This effect was specific to amnestic subtypes (MCI reverters vs nonreverters: amnestic MCI HR 3.3, = 0.006; nonamnestic MCI: HR 1.3, = 0.67).
Our findings indicate that the relevance of reversion for progression risk depends on the MCI subtype. Subtype specificity and longitudinal characterization are required for the reliable identification of individuals at high risk of developing dementia.
我们试图通过纵向研究社区样本中不同的轻度认知障碍（MCI）亚型、向痴呆症的进展以及恢复正常认知的情况，来更好地了解MCI的发展轨迹。
作为正在进行的前瞻性队列研究——悉尼记忆与衰老研究的一部分，我们在4次两年一次的评估中评估了MCI亚型的稳定性和患痴呆症的风险。
虽然在所有评估中MCI及不同MCI亚型的患病率相对稳定，但从MCI恢复以及在不同MCI亚型之间转换的情况很常见。在基线时被归类为MCI的参与者中，高达46.5%在随访期间的某个时间点恢复了正常。大多数（83.8%）新发痴呆症的参与者在痴呆症诊断前2年被诊断为MCI。与基线时无MCI的参与者相比，恢复者和MCI稳定的参与者发展为痴呆症的风险均增加（风险比分别为6.4，P = 0.02和24.7，P < 0.001）；然而，未恢复的MCI参与者患痴呆症的风险高于恢复者（风险比为2.5，P = 0.01）。这种效应在遗忘型亚型中尤为明显（MCI恢复者与未恢复者：遗忘型MCI风险比3.3，P = 0.006；非遗忘型MCI：风险比1.3，P = 0.67）。
我们的研究结果表明，恢复对进展风险的相关性取决于MCI亚型。为了可靠地识别有发展为痴呆症高风险的个体，需要亚型特异性和纵向特征描述。
