Impact of Protein Energy Malnutrition on Hospitalized Patients with Amyloidosis: A United States Population-Based Cohort Study

Background

Amyloidosis can affect virtually any organ system and lead to a multitude of clinical manifestations. Patients with amyloidosis tend to have varying degrees of protein energy malnutrition (PEM) due to multiple reasons, including cachexia, sarcopenia, and systemic involvement. End organ damage, including renal failure, heavy proteinuria, and malabsorption due to gastrointestinal involvement, further complicates the clinical picture. The impact of PEM on clinical outcomes in this subgroup needs further exploration.

Methods

We utilized the 2020 National Inpatient Sample (NIS) Database in conducting this retrospective cohort study. We identified patients with amyloidosis and PEM using appropriate ICD-10 diagnostic codes. We stratified patients with amyloidosis based on the presence or absence of PEM. A survey multivariable logistic and linear regression analysis was used to calculate adjusted odds ratios (ORs) for the primary and secondary outcomes. A p value of <0.05 was considered statistically significant. The aim of this study was to investigate the impact of PEM on in-hospital mortality, hospital length of stay (LOS), and total hospitalization charges among hospitalized patients with amyloidosis.

Results

We identified a total of 3525 hospitalized patients with amyloidosis, of which 12.48% (440/3525) had comorbid PEM. The overall in-hospital mortality among patients with amyloidosis was 5.39% (190/3525). Among those with concomitant PEM, the mortality rate was significantly higher at 12.50% (55/440, p=0.001). Utilizing a stepwise survey multivariable logistic regression model that adjusted for patient and hospital level confounders, PEM was found to be an independent predictor of increased in-hospital mortality (adjusted OR 2.69; 95% (confidence interval [CI] 1.23-5.85; p=0.013), longer LOS (coefficient 3.09; CI 0.12-6.06; p=0.041), higher total hospitalization charges ($59817; [CI] $8531-$111104; p=0.022), and increased need for mechanical ventilation (adjusted OR 2.21; CI 1.00-4.86; p=0.049).

Conclusion

Our analysis demonstrated that PEM was widely prevalent in hospitalized patients with amyloidosis. It was associated with significantly worsened in-hospital mortality, longer LOS, total cost of healthcare utilization, and increased need for mechanical ventilation. Efforts should be made to promote nutritional assessment and screening mechanisms with the aim to include early nutritional support as indicated. Further prospective studies with larger sample size are warranted to better understand these associations.

No relevant conflicts of interest to declare.