Unraveling the Link between Malnutrition and Adverse Clinical Outcomes: Association of Acute and Chronic Malnutrition Measures with Blood Biomarkers from Different Pathophysiological States.

BACKGROUND AND AIMS Malnutrition is associated with poor clinical outcomes. Whether there is a causal relationship or it merely mirrors a severe patient condition remains unclear. We examined the association of malnutrition with biomarkers characteristic of different pathophysiological states to better understand the underlying etiological mechanisms. METHODS We prospectively followed consecutive adult medical inpatients. Multivariable regression models were used to investigate the associations between malnutrition - as assessed using the Nutritional Risk Screening (NRS 2002) - and biomarkers linked to inflammation, stress, renal dysfunction, nutritional status and hematologic function. RESULTS A total of 529 patients were included. In a fully adjusted model, malnutrition was significantly associated with the inflammatory markers procalcitonin (0.20, 95% CI 0.03-0.37), proadrenomedullin (0.28, 95% CI 0.12-0.43) and albumin (-0.39, 95% CI -0.57 to -0.21), the stress marker copeptin (0.34, 95% CI 0.17-0.51), the renal function marker urea (0.23, 95% CI 0.07-0.38), the nutritional markers vitamin D25 (-0.22, 95% CI -0.41 to -0.02) and corrected calcium (0.29, 95% CI 0.10-0.49) and the hematological markers hemoglobin (-0.27, 95% CI -0.43 to -0.10) and red blood cell distribution width (0.26, 95% CI 0.07-0.44). Subgroup analysis suggested that acute malnutrition rather than chronic malnutrition was associated with elevated biomarker levels. CONCLUSION Acute malnutrition was associated with a pronounced inflammatory response and an alteration in biomarkers associated with different pathophysiological states. Interventional trials are needed to prove causality