Bilingualism is thought to confer advantages in executive functioning, thereby contributing to cognitive reserve and a later age of dementia symptom onset. While the relation between bilingualism and age of onset has been explored in Alzheimer's dementia, there are few studies examining bilingualism as a contributor to cognitive reserve in frontotemporal dementia (FTD). In line with previous findings, we hypothesized that bilinguals with behavioral variant FTD would be older at symptom onset compared to monolinguals, but that no such effect would be found in patients with nonfluent/agrammatic variant primary progressive aphasia (PPA) or semantic variant PPA. Contrary to our hypothesis, we found no significant difference in age at symptom onset between monolingual and bilingual speakers within any of the FTD variants, and there were no notable differences on neuropsychological measures. Overall, our results do not support a protective effect of bilingualism in patients with FTD-spectrum disease in a U.S. based cohort.

双语被认为在执行功能方面具有优势，从而有助于认知储备和老年痴呆症症状的较晚发生。虽然双语与阿尔茨海默氏痴呆症发病年龄之间的关系已被探索，但很少有研究将双语作为额颞叶痴呆 (FTD) 认知储备的一个因素进行检验。与之前的研究结果一致，我们假设患有行为变异型 FTD 的双语者与单语者相比，症状出现时年龄更大，但在非流利/语法失语变异型原发性进行性失语症 (PPA) 或语义变异型 PPA 患者中不会发现这种效应。与我们的假设相反，我们发现任何 FTD 变体中单语和双语使用者之间症状出现的年龄没有显着差异，并且神经心理学指标也没有显着差异。总体而言，我们的结果并不支持双语对美国队列中 FTD 谱系疾病患者的保护作用。