Association between migration and cognitive status among middle-aged and older adults: a systematic review

BACKGROUND: This study aimed to synthesize the current literature examining the association between migration and cognitive function among middle-aged and older adults. METHODS: We used the PRISMA as a guideline for this systematic review and searched the following databases: PubMed, CINAHL, EMBASE, and Global Health. RESULTS: Twenty-five published studies were included. Twenty-two studies were focused on international migrants, while only 3 studied internal migrants. Fourteen studies were conducted in the United States, followed by UK (n = 2), Israel (n = 2), India (n = 2) and other countries like Canada and Australia. Some studies showed that middle-aged and older migrants demonstrated poorer cognitive function comparing to non-migrants in hosting places; while other studies indicated no association between migration and cognitive function. A higher level of acculturation was associated with better performance on cognitive function tests among migrants. CONCLUSION: It is unclear how or whether migration and cognitive function are related. The quality of current literature suffered from methodological deficiencies. Additional research is needed to examine the linkages using more comprehensive measures of migration and cognitive function.