Background: Cognitive impairment without dementia (CIND) and acute myocardial infarction (AMI) are prevalent in older adults; however, the association of CIND with outcomes after AMI is unknown. Methods: We used a multicenter registry to study 772 patients ≤65 years with AMI, enrolled between April 2005 and December 2008, who underwent cognitive function assessment with the Telephone Interview for Cognitive Status-modified (TICS-m) 1 month after AMI. Patients were categorized by cognitive status to describe characteristics and in-hospital treatment, including quality of life and survival 1 year after AMI. Results: Mean age was 73.2 ± 6.3 years; 58.5% were men, and 78.2% were white. Normal cognitive function (TICS-m >22) was present in 44.4%; mild CIND (TICS-m 19-22) in 29.8%; and moderate/severe CIND (TICS-m <19) in 25.8% of patients. Rates of hypertension (72.6%, 77.4%, and 81.9%), cerebrovascular accidents (3.5%, 7.0%, and 9.0%), and myocardial infarction (20.1%, 22.2%, and 29.6%) were higher in those with lower TICS-m scores (P <.05 for comparisons). AMI medications were similar by cognitive status; however, CIND was associated with lower cardiac catheterization rates (P =.002) and cardiac rehabilitation referrals (P <.001). Patients with moderate/severe CIND had higher risk-adjusted 1-year mortality that was nonstatistically significant (adjusted hazard ratio 1.97, 95% CI 0.99-3.94, P =.054; referent normal, TICS-m >22). Quality of life across cognitive status was similar at 1 year. Conclusions: Most older patients surviving AMI have measurable CIND. Cognitive impairment without dementia was associated with less invasive care, less referral and participation in cardiac rehabilitation, and worse risk-adjusted 1-year survival in those with moderate/severe CIND, making it an important condition to consider in optimizing AMI care.