Kamath Vidyulata, Crawford Jeffrey, DuBois Samantha, Nucifora Frederick C, Nestadt Gerald, Sawa Akira, Schretlen David
Department of Psychiatry and Behavioral Sciences.
Neuropsychology. 2019 Feb;33(2):203-211. doi: 10.1037/neu0000502. Epub 2018 Nov 26.
First-episode schizophrenia and schizoaffective patients (SZ+) show olfactory impairments, but how these relate to cognitive dysfunction remains unclear. We examined the relationship between cognitive and olfactory dysfunction in SZ+ and the clinical utility of these measures in the assessment of SZ+ patients.
First-episode SZ+ patients (n = 63) and controls (n = 63) were administered tests of odor identification and discrimination in addition to measures of manual dexterity, processing speed, attention and working memory, executive functioning, ideational fluency, and memory. We analyzed the relationships between olfactory and cognitive variables and conducted stepwise multiple regressions to identify which cognitive indices best predicted olfactory performance within the SZ+ group. Linear discriminant analysis was used to identify which measures best distinguished cases from controls.
Among patients, odor discrimination correlated with perseverative errors and odor identification correlated with bilateral manual dexterity. Odor discrimination performance was best predicted by perseverative errors and letter fluency, whereas odor identification ability was best predicted by manual dexterity. Stepwise linear discriminant analysis revealed that manual dexterity, letter-guided word fluency, and odor discrimination best distinguished SZ+ from healthy adults.
These findings indicate that manual dexterity, letter-guided word fluency, and odor discrimination may provide incremental information that strengthens a diagnosis of SZ+. Although odor discrimination tasks have received limited attention in schizophrenia studies, the extant data along with the present results indicate that odor discrimination tasks may have utility over odor identification measures as a neurodevelopmental risk marker. Additional studies examining odor discrimination as a predictor of SZ spectrum illness are warranted. (PsycINFO Database Record (c) 2019 APA, all rights reserved).
首发精神分裂症和分裂情感性障碍患者（SZ+）存在嗅觉障碍，但这些障碍与认知功能障碍之间的关系尚不清楚。我们研究了SZ+患者认知与嗅觉功能障碍之间的关系，以及这些测量方法在评估SZ+患者中的临床效用。
除了对手部灵活性、处理速度、注意力和工作记忆、执行功能、观念流畅性和记忆进行测量外，还对首发SZ+患者（n = 63）和对照组（n = 63）进行了气味识别和辨别测试。我们分析了嗅觉和认知变量之间的关系，并进行逐步多元回归，以确定哪些认知指标能最好地预测SZ+组内的嗅觉表现。采用线性判别分析来确定哪些测量方法能最好地区分病例与对照。
在患者中，气味辨别与持续性错误相关，气味识别与双侧手部灵活性相关。持续性错误和字母流畅性最能预测气味辨别表现，而手部灵活性最能预测气味识别能力。逐步线性判别分析显示，手部灵活性、字母引导的单词流畅性和气味辨别最能区分SZ+患者与健康成年人。
这些发现表明，手部灵活性、字母引导的单词流畅性和气味辨别可能提供额外信息，加强对SZ+的诊断。尽管气味辨别任务在精神分裂症研究中受到的关注有限，但现有数据以及目前的结果表明，作为神经发育风险标志物，气味辨别任务可能比气味识别测量更有用。有必要进行更多研究，将气味辨别作为SZ谱系疾病的预测指标。（PsycINFO数据库记录（c）2019美国心理学会，保留所有权利）
