A retrospective study of the incidence and characteristics of long-stay adult inpatients with hospital-acquired malnutrition across five Australian public hospitals.

Background/objectives: While malnutrition is prevalent in hospitals, little is known about patients who first become malnourished during the hospital stay. This study aimed to determine the incidence and describe the characteristics of patients who developed hospital-acquired malnutrition (HAM) across five Australian public hospitals.

Subjects/methods: A retrospective clinical audit of hospital data was conducted. Adult patients (aged ≥ 18 years) with a length of stay (LOS) > 14 days in a Metro South Health hospital between July 2015 and January 2019 were eligible. Demographic and clinical data were sourced from hospital data and medical records. Dietitians reviewed the medical records of patients clinically coded with malnutrition to determine HAM incidence. Univariate and logistic regression analyses were used to determine patient descriptors associated with HAM, compared with those not malnourished or those malnourished on admission.

Results: A total of 17,717 patients were eligible (45% F, 63 ± 20 years, LOS 24 (15-606) days). HAM incidence in long-stay patients was 1%, with an overall malnutrition prevalence of 18%. Patients with HAM had an ~26 days longer LOS than patients who were malnourished on admission or not malnourished (p < 0.001). Longer LOS; patient inter-hospital transfer from or to another hospital; or experiencing cognitive impairment, pressure injury or a fall while in hospital were associated with HAM (OR 1.006-3.6, p < 0.05).

Conclusions: Incidence of HAM, defined as malnutrition first diagnosed >14 days after admission, was in the low end of the published range. HAM was significantly associated with long LOS, transferring between hospitals and developing a cognitive impairment, pressure injury or fall during admission.