Inflammation as a diagnostic criterion in the GLIM definition of malnutrition—what CRP-threshold relates to reduced food intake in older patients with acute disease?

BACKGROUND/OBJECTIVES: In the recently introduced GLIM diagnosis of malnutrition, details of how to classify inflammation as an etiologic criterion are lacking. This study aimed to determine at what level of serum C-reactive protein (CRP) the risk of low food intake increases in acutely ill older hospitalized patients. SUBJECTS/METHODS: A total of 377 consecutively admitted geriatric acute care patients were analyzed. Nutritional intake was determined using the food intake item of Nutritional Risk Screening and the plate diagram method and grouped into >75%, 50–75% and ≤50% of requirements. CRP was measured and categorized into 0.0–0.99, 1.0–1.99, 2.0–2.99, 3.0–4.99, 5.0–9.99 and ≥10.0 mg/dl. RESULTS: Of the total population (mean age 82.2 ± 6.6 years; 241 females), 82 (22%) had intake <50% of requirements and 126 (33%) demonstrated moderate to severe inflammation. Patients with food intake <50% of requirements had significantly higher median CRP than those with intake >75% (P < 0.001). Groups with CRP ≥3.0 mg/dl had a markedly higher proportion of patients with low food intake (<50% and <75%). CONCLUSION: A serum-CRP of 3.0 mg/dl appears to be a reasonable threshold of acute inflammation leading to reduced food intake, serving as an orientation for the inflammation criterion of the GLIM diagnosis in acutely ill older patients.