RESUMEN
INTRODUCTION: Sexual minority discrimination might lead to a higher risk of mild cognitive impairment (MCI) and dementia. The aim of this study was to assess the risk of MCI and dementia between older adults in same-sex relationships (SSR) and opposite-sex relationships (OSR). METHODS: We analyzed longitudinal data from the National Alzheimer's Coordinating Center up to September 2017. Analyses included cognitively normal individuals 55+ at baseline who had a spouse, partner, or companion as study partner at any assessment. Associations were calculated using survival analysis adjusting for demographics and APOE-e4 carrier status. RESULTS: Hazard ratios of MCI and dementia did not differ statistically between SSR and OSR individuals in the total sample nor stratified by sex. CONCLUSION: The lack of association between SSR and MCI and dementia warrants future research into their potential resilience mechanisms and the inclusion of sexual minority status questions in research and surveillance studies. The potential recruitment bias caused by nonprobabilistic sampling of the cohort and the reporting and ascertainment bias caused by using SSR to infer sexual minority status may have influenced our findings.