Impact of malnutrition on in-hospital outcomes in patients with acute myocardial infarction and no standard modifiable cardiovascular risk factors.

BACKGROUND

Individuals who present with acute myocardial infarction (AMI) in the absence of standard modifiable cardiovascular risk factors (i.e. SMuRF-less) seem to have a significantly increased risk of mortality; however, it remains unclear whether the 'SMuRF paradox' would be influenced by patients' baseline nutritional status.

METHODS

We consecutively included patients from a multi-center, prospective registry (NCT05337319) from January 2022 to October 2023. Malnutrition was defined via the Nutritional Risk Index. The primary outcome was in-hospital major adverse cardiovascular events (MACEs), which included mortality, cardiac shock, acute congestive heart failure, reinfarction, and stroke.

RESULTS

A total of 3753 patients with first-presentation AMI were included, of which 10 % were SMuRF-less and over 21 % were malnourished. SMuRF-less malnourished had the highest MACEs (16.1 %), followed by the SMuRF-less nourished (15.5 %), ≥1 SMuRFs malnourished (12.1 %), and ≥1 SMuRFs nourished (5.2 %, p < 0.001). With ≥1 SMuRFs nourished as the reference, SMuRF-less malnourished had the highest increase in MACEs [adjusted OR (95 % CI), 3.385 (2.163-5.298), p < 0.001], followed by SMuRF-less nourished group [adjusted OR (95 % CI), 2.460 (1.214-4.985), p = 0.012], but only a nonsignificant increase in MACEs was observed in the ≥1 SMuRFs malnourished [adjusted OR (95 % CI), 1.297 (0.880-1.911), p = 0.188]. SMuRF-less was not associated with MACEs in the subgroup of malnourished patients [adjusted OR (95 % CI), 1.931 (0.892-4.178), p = 0.095], with a nonsignificant result in interaction analysis (p for interaction = 0.148).

CONCLUSION

Among patients with first-presentation AMI, malnutrition is prevalent, especially in those SMuRF-less. Compared with those with at least one SMuRF, SMuRF-less patients have a significantly higher risk of in-hospital MACEs irrespective of their nutritional status, while the outcome was the most favorable among ≥1 SMuRF and nourished patients.