Recent and current low food intake – prevalence and associated factors in hospital patients from different medical specialities

Malnutrition significantly impacts patient outcomes, increasing complication rates, hospital stays, and healthcare costs. Low food intake is a primary contributor to malnutrition and a risk factor for mortality. Multiple factors contribute to reduced food intake, including disease-related, hospital-related, and individual factors. Previous research has highlighted variations in malnutrition prevalence across medical specialties, with higher rates observed in oncology, long-term care, and infectious disease units. However, comprehensive data comparing low food intake and associated factors across different specialties, particularly in German hospitals, are limited. This study aimed to determine the prevalence of recent and current low food intake (LIRC), defined as reduced eating both on the survey day and in the week before hospital admission, and to identify associated factors across various medical disciplines in German hospitals using the nutritionDay survey data.

Existing literature indicates that malnutrition is a significant problem in hospitalized patients, leading to adverse clinical outcomes and increased healthcare costs. Low food intake is a major factor contributing to malnutrition and has been linked to increased 30-day mortality. Studies using tools like the Malnutrition Screening Tool (MST) and the Subjective Global Assessment (SGA) have shown varying prevalence rates of malnutrition across different medical specialties, with higher rates in oncology, gastroenterology, and geriatrics. Previous research has also examined reduced food intake in the week prior to a survey day, finding higher prevalence in surgical patients. However, a detailed comparison of medical specialities regarding low food intake and associated factors is lacking. Up-to-date information on malnutrition in German hospitals is limited, highlighting the need for this study using the German nutritionDay database.

This study analyzed data from the nutritionDay survey, a cross-sectional study conducted annually in hospitals worldwide. The study included adult patients (≥18 years) from German hospital units participating in the nutritionDay surveys from 2016 to 2020. Patients from the nutritionDay express survey were excluded due to a reduced questionnaire, as were those without consent, missing information on specialty and sex, or from wards with less than 75% completed outcome sheets. LIRC was defined based on patient-reported data on lunch eaten on nutritionDay and the amount of food eaten before hospital admission. Categorical variables were used to represent food intake (normal vs. reduced), age, sex, BMI, admission type, medication number, surgery history, ICU admission, terminal illness, and presence of various diseases. Self-reported weight loss in the three months prior to nutritionDay and the ability to walk without assistance were also included. Univariate and multivariate binary logistic regression models were used to identify factors associated with LIRC, both overall and within different medical specialties. Continuous independent variables were categorized for simplicity. Odds ratios (OR) with 95% confidence intervals (CI) were reported, with p<0.1 used as the inclusion criterion for the multivariate model.

A total of 1865 patients from 127 units in 44 hospitals were included in the analysis. LIRC was observed in 21.1% of all patients. The prevalence of LIRC varied across medical specialties, ranging from 11.2% in Neurology to 26.6% in Gastroenterology. Univariate analysis identified several factors potentially associated with LIRC. Multivariate logistic regression analysis in the total sample showed that female sex (OR 1.98, 95% CI 1.50–2.61), weight loss (OR 2.62, 95% CI 1.93–3.56), uncertain weight loss history (OR 1.90, 95% CI 1.03–3.51), emergency admission (OR 1.38, 95% CI 1.02–1.86), digestive disease (OR 1.90, 95% CI 1.40–2.56), poor or very poor self-rated health (OR 2.17, 95% CI 1.62–2.91), and inability to walk without assistance (OR 1.55, 95% CI 1.14–2.12) were positively associated with LIRC. In contrast, cardiac insufficiency (OR 0.55, 95% CI 0.37–0.83) and neurological ward admission (OR 0.51, 95% CI 0.28–0.92) were associated with a reduced risk of LIRC. Specialty-specific analyses showed that the associations and consistency with the whole sample were most evident in Gastroenterology and Oncology patients. No significant associations were found in Neurology and Geriatrics, potentially due to low LIRC prevalence in Neurology and data quality issues in Geriatrics.

This study's findings highlight the significant prevalence of LIRC among German hospital patients, confirming low food intake as a major factor in malnutrition. The observation of LIRC, encompassing both recent and current low intake, provides a more comprehensive understanding of nutritional status than single-point assessments. The higher prevalence of LIRC in Gastroenterology and Oncology compared to Neurology and Geriatrics suggests a discipline-specific approach is necessary. The association of LIRC with female sex, weight loss, poor health, and decreased functional status reinforces the importance of considering these factors in nutritional risk assessments. The unexpected inverse relationship between cardiac insufficiency and LIRC warrants further investigation. Limitations in data quality in the Geriatrics group and the cross-sectional design restrict the ability to draw definitive causal conclusions.

This study demonstrates a high prevalence of recent and current low food intake (LIRC) among German hospital patients, varying across medical specialties. Female sex, weight loss, poor self-rated health, and mobility limitations were consistently associated with LIRC. These findings emphasize the need for discipline-specific assessments of nutritional intake at admission and ongoing monitoring during hospitalization to facilitate timely interventions. Future research should explore the impact of nutritional interventions on clinical outcomes and extend the analysis to larger international samples, incorporating dynamic measures of food intake and analyzing outcome data in LIRC patients.

The study's limitations include the reliance on self-reported food intake data, which may be subject to recall bias and individual perception. The cross-sectional design limits the ability to establish causality. The sample may not be fully representative of the entire German hospital population, due to potential overrepresentation of older patients and patients with specific diseases, and underrepresentation of severely ill patients. Data quality issues, particularly missing data in certain specialties like Geriatrics, affected the statistical power of the analysis.