Clinical Manifestations.

Abstract

Older adults may experience decreased social support, which has been linked to cognitive decline and increased risk of dementia. Immigrants may also experience more social isolation due to discrimination and fear of deportation. This study examined social networks, nativity status, and neurocognitive functioning(NC) in an ethnoculturally diverse sample of middle/older adults. Participants included 26 immigrants (Mage= 64.12, SD = 5.64) and 109 U.S.-born adults (Mage= 65.37, SD = 7.10). Participants completed a comprehensive NC battery and the Berkman-Syne Social Network Index(SNI; a well-validated self-reported questionnaire assessing close social support, where higher scores represent more social support). Demographically-adjusted norms were used to compute average global NC and domain T-scores. A series of hierarchical multiple regressions were computed to predict global and domain NC T-scores. SNI and age were entered at Step-One, the interaction term(age*SNI) was entered at Step-Two, and nativity status was entered at Step-Three. Results revealed that the omnibus model was significantly associated with Attention/Working Memory(A/WM) (R² = .13; ps = .009) and Processing Speed(PS) (R² = .20; ps = .002). Notably Step-Three of the model significantly contributed to the association of AWM (R²Δ= .11; ps<.05) and PS (R²Δ= .09; ps<.05) beyond Step-One and Step-Two. For A/WM, the interaction term, and nativity status (𝛽s = .04-6.96, respectively; ps<.05) were significantly associated with A/WM. For PS, SNI, the interaction term, and nativity status (𝛽s = -3.91-8.17; ps<.05) were significantly associated with PS. Such that, there is a main effect of nativity status with immigrants scoring lower on measures of A/WM by 6.96 and PS by 8.17 units. Overall, there is a negative association between age and A/WM and PS but as SNI increases the relation between age and NC becomes positive. Only nativity status (𝛽s = 5.99-8.23; ps<.05) significantly predicted Memory, Verbal Fluency, and Global NC functioning scores. Findings show that among middle/older adults, both SNI and nativity status are associated with A/WM and PS, suggesting that a larger SNI can serve as a protective factor against the effects of aging on NC functioning. Importantly, even when SNI and age were not significantly related to NC T-scores, nativity status was. Nativity status likely serves as a proxy for other risk factors (e.g., healthcare access), which should be explored in future studies.