Copenhagen Research Center for Mental Health - CORE, Mental Health Center Copenhagen, Copenhagen University Hospital, Copenhagen, Denmark.
Center for Clinical Intervention and Neuropsychiatric Schizophrenia Research (CINS), Mental Health Center Glostrup, Copenhagen University Hospital, Glostrup, Denmark.
Brain Behav. 2021 Mar;11(3):e01962. doi: 10.1002/brb3.1962. Epub 2021 Jan 23.
Widespread neurocognitive impairment is well-established in individuals at ultra-high risk (UHR) for developing psychoses, but it is unknown whether slowed processing speed may underlie impairment in other neurocognitive domains, as found in schizophrenia. The study delineated domain functioning in a UHR sample and examined if neurocognitive slowing might account for deficits across domains.
The cross-sectional study included 50 UHR individuals with no (n = 38) or minimal antipsychotic exposure (n = 12; mean lifetime dose of haloperidol equivalent = 17.56 mg; SD = 13.04) and 50 matched healthy controls. Primary analyses compared group performance across neurocognitive domains before and after covarying for processing speed. To examine the specificity of processing speed effects, post hoc analyses examined the impact of the other neurocognitive domains and intelligence as covariates.
UHR individuals exhibited significant impairment across all neurocognitive domains (all ps ≤ .010), with medium to large effect sizes (Cohen's ds = -0.53 to -1.12). Only processing speed used as covariate eliminated significant between-group differences in all other domains, reducing unadjusted Cohen's d values with 68% on average, whereas the other domains used as covariates averagely reduced unadjusted Cohen's d values with 20% to 48%. When covarying each of the other domains after their shared variance with speed of processing was removed, all significant between-group domain differences remained (all ps ≤ .024).
Slowed processing speed may underlie generalized neurocognitive impairment in UHR individuals and represent a potential intervention target.
广泛的神经认知损伤在处于精神病发展超高风险（UHR）的个体中已得到充分证实，但目前尚不清楚处理速度是否会像精神分裂症那样导致其他神经认知领域的损伤。本研究描绘了 UHR 样本的各领域功能，并探讨了神经认知速度减慢是否可能导致各领域的缺陷。
这项横断面研究纳入了 50 名 UHR 个体，其中无（n=38）或仅有最低抗精神病药物暴露（n=12；利培酮等效终身剂量均值=17.56mg；SD=13.04），并与 50 名匹配的健康对照者进行比较。主要分析在协变量为处理速度后，比较了两组在神经认知领域的表现。为了检验处理速度影响的特异性，事后分析检验了其他神经认知领域和智力作为协变量的影响。
UHR 个体在所有神经认知领域均表现出显著损伤（所有 p 值均≤.010），具有中到大的效应量（Cohen's d 值为-0.53 至-1.12）。仅将处理速度作为协变量，即可消除所有其他领域中组间的显著差异，平均降低未调整的 Cohen's d 值 68%，而其他领域作为协变量平均降低未调整的 Cohen's d 值 20%至 48%。当在去除与处理速度的共同方差后，对其他各领域进行协变量分析时，所有组间领域差异仍然显著（所有 p 值均≤.024）。
处理速度减慢可能是 UHR 个体普遍存在神经认知损伤的基础，代表了一个潜在的干预靶点。
