Epidemiology and clinical outcomes of malnutrition in hospitalized patients with stroke, 1998-2022

Stroke is a leading cause of mortality and long-term disability, particularly for the ageing populations. Malnutrition is frequent but under-recognized among patients with stroke. Evidence on its determinants and in-hospital consequences at population level remains limited.

Nationwide retrospective analysis of patients with stroke using the Swiss hospital discharge data from 1998 to 2022. Malnutrition was defined as ICD-10 codes E40 to E46 (definition M1) or ICD-10 codes plus presence of (par)enteral nutrition among hospitalizations devoid of a malnutrition ICD-10 code. Associations between malnutrition and clinical outcomes such as Intensive Care Unit (ICU) admission, prolonged (>5 days) Length of Stay (LoS) and in-hospital mortality were studied using bivariate and multivariable analyses.

Malnutrition (definition M1) was identified in 3.5% of the 504,192 hospitalizations (46.2% female). The prevalence of malnutrition diagnosis (based on codes) increased from 0.17% in 1998 to 9.31% in 2022 (p for trend <0.001). After multivariable analysis, malnutrition (definition M1) was associated with a higher likelihood of ICU admission [OR (95% CI): 1.16 (1.11-1.21)), prolonged LoS [8.14 (7.64-8.67)] but lower in-hospital mortality [0.81 (0.76-0.86)]. Malnutrition (definition M2) was associated with a higher likelihood of ICU admission [2.94 (2.86-3.02)], prolonged LoS [5.02 (4.83-5.21)] and in-hospital mortality [1.43 (1.37-1.48)].

Hospital malnutrition among patients with stroke appears increasingly prevalent yet underestimated. Malnutrition is associated with adverse outcomes, particularly longer LoS and higher ICU admission rates, although associations with mortality varied by definition. This underscores the need for better screening and intervention practices.