Background Binary reversals (exemplified by ‘yes’/‘no’ confusions) have been described in patients with primary progressive aphasia (PPA) but their diagnostic value and phenotypic correlates have not been defined. Methods We conducted a retrospective cohort study analysing demographic, clinical, neuropsychological, linguistic and behavioural data from patients representing all major PPA syndromes (non-fluent/agrammatic variant, nfvPPA; logopenic variant, lvPPA; semantic variant, svPPA) and behavioural variant frontotemporal dementia (bvFTD). The prevalence of binary reversals and behavioural abnormalities, illness duration, parkinsonian features and neuropsychological test scores were compared between neurodegenerative syndromes, and the diagnostic predictive value of binary reversals was assessed using logistic regression. Results Data were obtained for 83 patients (21 nfvPPA, 13 lvPPA, 22 svPPA, 27 bvFTD). Binary reversals occurred in all patients with nfvPPA, but significantly less frequently and later in lvPPA (54%), svPPA (9%) and bvFTD (44%). Patients with bvFTD with binary reversals had significantly more severe language (but not general executive or behavioural) deficits than those without reversals. Controlling for potentially confounding variables, binary reversals strongly predicted a diagnosis of nfvPPA over other syndromes. Conclusions Binary reversals are a sensitive (though not specific) neurolinguistic feature of nfvPPA, and should suggest this diagnosis if present as a prominent early symptom.

中文翻译：

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二元逆转：原发性进行性失语症的诊断标志

背景 在原发性进行性失语症 (PPA) 患者中已经描述了二元逆转（以“是”/“否”混淆为例），但其诊断价值和表型相关性尚未确定。方法 我们进行了一项回顾性队列研究，分析了代表所有主要 PPA 综合征（不流利/语法变异，nfvPPA；语词减少变异，lvPPA；语义变异，svPPA）和行为变异额颞叶痴呆的患者的人口统计学、临床、神经心理学、语言和行为数据。 （bvFTD）。比较神经退行性综合征之间二元逆转和行为异常的发生率、病程、帕金森特征和神经心理学测试分数，并使用逻辑回归评估二元逆转的诊断预测价值。结果 获得了 83 名患者的数据（21 名 nfvPPA、13 名 lvPPA、22 名 svPPA、27 名 bvFTD）。二元逆转发生在所有 nfvPPA 患者中，但在 lvPPA (54%)、svPPA (9%) 和 bvFTD (44%) 患者中发生频率明显较低且较晚。患有二元逆转的 bvFTD 患者比没有逆转的患者有更严重的语言（但不是一般执行或行为）缺陷。控制潜在的混杂变量后，二元反转强烈预测 nfvPPA 的诊断优于其他综合征。结论 二元逆转是 nfvPPA 的一个敏感（尽管不是特异性）神经语言学特征，如果作为突出的早期症状出现，则应提示该诊断。