Abstract:Cognitive decline and functional impairment present significant challenges for aging populations, particularly among U.S. military Veterans who face unique service-related risk factors. Veterans have higher rates of posttraumatic stress disorder (PTSD), traumatic brain injury (TBI), and depression, all of which have been associated with increased risk for dementia and functional impairment. Additional risk factors including bipolar disorder, schizophrenia, and substance use history, have also been linked to risk of developing dementia and cognitive impairment. Given these links, this study examined the relationship between cognitive impairment and functional impairment in Veterans aged 65 and older, with a focus on how comorbid conditions exacerbate declines in activities of daily livings (ADLs) and instrumental activities of daily living (IADLs).Using archival data from the Health and Retirement Study (HRS), a nationally representative longitudinal cohort study, this research categorizes Veterans into three cognitive groups: normal cognition, mild cognitive impairment (MCI), and dementia. Functional impairment is assessed through difficulties in activities of daily living (ADLs) and instrumental activities of daily living (IADLs). Statistical analyses evaluated differences in functional impairment between groups and investigated whether Veterans with multiple comorbidities experience greater impairments compared to those without.