Body Mass Index and In-Hospital Management and Outcomes of Acute Myocardial Infarction

Abstract

Background and Objectives: Contemporary data on the prevalence, management and outcomes of acute myocardial infarction (AMI) in relation to body mass index (BMI) are limited. Materials and Methods: Using the National Inpatient Sample from 2008 through 2017, we identified adult AMI hospitalizations and categorized them into underweight (BMI < 19.9 kg/m2), normal BMI and overweight/obese (BMI > 24.9 kg/m2) groups. We evaluated in-hospital mortality, utilization of cardiac procedures and resource utilization among these groups. Results: Among 6,089,979 admissions for AMI, 38,070 (0.6%) were underweight, 5,094,721 (83.7%) had normal BMI, and 957,188 (15.7%) were overweight or obese. Over the study period, an increase in the prevalence of AMI was observed in underweight and overweight/obese admissions. Underweight AMI admissions were, on average, older, with higher comorbidity, whereas overweight/obese admissions were younger and had lower comorbidity. In comparison to the normal BMI and overweight/obese categories, significantly lower use of coronary angiography (62.3% vs. 74.6% vs. 37.9%) and PCI (40.8% vs. 47.7% vs. 19.6%) was observed in underweight admissions (all p < 0.001). The underweight category was associated with significantly higher in-hospital mortality (10.0% vs. 5.5%; OR 1.23 (95% CI 1.18–1.27), p < 0.001), whereas being overweight/obese was associated with significantly lower in-hospital mortality compared to normal BMI admissions (3.1% vs. 5.5%; OR 0.73 (95% CI 0.72–0.74), p < 0.001). Underweight AMI admissions had longer lengths of in-hospital stay with frequent discharges to skilled nursing facilities, while overweight/obese admissions had higher hospitalization costs. Conclusions: In-hospital management and outcomes of AMI vary by BMI. Underweight status was associated with worse outcomes, whereas the obesity paradox was apparent, with better outcomes for overweight/obese admissions.

Factors Associated with Increased Length of Stay in Post Primary Percutaneous Coronary Intervention Patients: A Scoping Review

“…13,34 Patients with extreme BMI (<18.5 and >40kg/m2) are also at increased risk of adverse outcomes after PCI. 48 Patients post-PPCI who were treated for more than 7 days had an average BMI of 24.22 kg/m2. 13 There is a relationship between obesity and coronary atherosclerosis, with hemodynamic, metabolic, and inflammatory factors as well as oxidative stress contributing to the development of cardiovascular disease in obese patients.…”

Association between Cardiovascular Risk Factors and High-risk Features in Myocardial Perfusion Imaging: A Multicenter Study

“… 42 , 43 The underlying cause is unclear; still, some hypotheses exist suggesting that the relevant studies had older underweight patients and more male patients. 44 Furthermore, a more detailed prognosis requires the assessment of central obesity by measuring waist circumference. 45 …”

Body Mass Index Is Independently Associated with the Presence of Ischemia in Myocardial Perfusion Imaging

“…For example, obese individuals may develop type II diabetes mellitus due to insulin resistance [ 36 , 37 ], followed later by adverse lipid profiles, eventually leading to CAD or other severe cardiovascular complications [ 38 , 39 ]. However, even though obese individuals are more prone to CAD, there have been reports of better prognosis in patients with high BMI after coronary artery occlusion or acute myocardial infarction [ 40 , 41 ]. Underweight individuals (BMI < 18.5 kg/m 2 ) with acute coronary syndromes exhibited a paradoxically worse prognosis than overweight individuals.…”

“…Furthermore, another study demonstrated that patients admitted to hospital for management of acute myocardial infarction had better prognosis when they were overweight or obese, followed by those with normal weight, while underweight patients exhibited the worst prognosis. The authors of that study reported that most of the underweight patients were older with more comorbidities compared to overweight patients, offering a probable explanation for this paradoxical finding [ 40 ].…”