A - 17 Effects of Bilingualism on Symptom Duration before Diagnosis of MCI

Abstract Objective While some studies (e.g., Bialystok et al., 2014; Brini et al., 2020) have identified a bilingual advantage in delaying age of onset for Mild Cognitive Impairment (MCI) (4.7 years) relative to monolingual individuals, inconsistencies have been attributed to immigration status and level of education, among others. The present study investigated the role of bilingualism on the age of MCI onset, symptom duration before diagnosis, and age at time of diagnosis MCI. Method Data from an outpatient neuropsychological clinic registry were examined for MCI. 177 adults ages 39–92 (monolingual = 121, bilingual = 56) were identified. Participants with Traumatic Brain Injury (TBI), acute psychosis, or dementia were excluded. Results Independent t-test showed monolingual individuals had significantly shorter duration of symptoms until diagnosis (32 months) than bilingual individuals (41 months; t (175) = −1.714, p = 0.044) despite the fact that there was no significant difference between monolingual and bilingual participants on age of symptom onset (t (175) = −0.033, p = 0.487) or age at diagnosis (t (175) = −0.456, p = 0.324). Years of education was not significant. Conclusion Bilingual patients had a longer course of symptoms before MCI diagnoses, providing support that bilingualism may aid in the preservation of cognitive function despite disease related progression associated with MCI. More detailed analysis accounting for quality of education, access to health care, socioeconomic status, immigration status, etc., is necessary to examine the complexity associated with bilingualism that may underlie the controversy around the bilingual advantage.