Comparing informant‐based measures of cognitive functioning between the US and Mexico

Background Informant reports are important for understanding cognitive impairment and dementia in older populations. Recently, several population‐based aging studies have included harmonized direct and informant assessments to assess the prevalence of dementia globally as part of the international Harmonized Cognitive Assessment Protocol (HCAP). However, the social and cultural contexts of nations, sociodemographic characteristics of informants, and the participant‐informant relationship may affect the accuracy of informant ratings of cognitive decline and functioning. This study examines the extent to which informant characteristics and the participant‐informant relationships are associated with informant‐reported cognitive function in the United States and Mexico. Methods Data are from the 2016 US Health and Retirement Study (HRS) HCAP (N = 2,918) and the Ancillary Study of Cognitive Aging in Mexico (Mex‐Cog) (N = 1,750). Informant‐reported cognitive function was measured by the informant Community Screening Instrument for Dementia (CSI‐D). Participants’ cognitive function was measured using the HCAP. We compared the characteristics of informants, informant ratings, and directly‐assessed cognitive functioning in both nations, and used regression to assess the association of informant characteristics and the participant‐informant relationship with the informant CSI‐D score. Results We find older Americans have worse informant‐reported cognitive functioning but higher directly‐assessed cognitive functioning than Mexicans. Nearly 80% of informants lived with the subject in Mexico, compared to less than half in the US. In both countries, older informants, children and other family members (compared to spouse) report less cognitive impairment. In Mexico, female informants reported more impairment. In the US, coresident informants reported more impairment. Conclusion This research shows how social environments influence informant reporting. Understanding heterogeneity in informants is vital when examining informant measures of cognitive function in cross‐countries studies.