Costs of hospital malnutrition

Hospital malnutrition has been established as a critical, prevalent, and costly problem in many countries. Many cost studies are limited due to study population or cost data used. The aims of this study were to determine: the relationship between malnutrition and hospital costs; the influence of confounders on, and the drivers (medical or surgical patients or degree of malnutrition) of the relationship; and whether hospital reported cost data provide similar information to administrative data. To our knowledge, the last two goals have not been studied elsewhere.

Univariate and multivariate analyses were performed on data from the Canadian Malnutrition Task Force prospective cohort study combined with administrative data from the Canadian Institute for Health Information. Subjective Global Assessment was used to assess the relationship between nutritional status and length of stay and hospital costs, controlling for health and demographic characteristics, for 956 patients admitted to medical and surgical wards in 18 hospitals across Canada.

After controlling for patient and hospital characteristics, moderately malnourished patients' (34% of surveyed patients) hospital stays were 18% (p = 0.014) longer on average than well-nourished patients. Medical stays increased by 23% (p = 0.014), and surgical stays by 32% (p = 0.015). Costs were, on average, between 31% and 34% (p-values < 0.05) higher than for well-nourished patients with similar characteristics. Severely malnourished patients (11% of surveyed patients) stayed 34% (p = 0.000) longer and had 38% (p = 0.003) higher total costs than well-nourished patients. They stayed 53% (p = 0.001) longer in medical beds and had 55% (p = 0.003) higher medical costs, on average. Trends were similar no matter the type of costing data used.

Over 40% of patients were found to be malnourished (1/3 moderately and 1/10 severely). Malnourished patients had longer hospital stays and as a result cost more than well-nourished patients.