A Dietitian-Driven Unified Nutritional Care Model (ADDUCE)

Disease-related malnutrition is common among hospitalised medical patients and is associated with prolonged hospital stay, poorer clinical outcomes, reduced quality of life, and increased healthcare costs. Although evidence-based guidelines recommend systematic nutritional risk screening and nutritional treatment, implementation in routine clinical practice remains inconsistent. In many healthcare systems, including Denmark, responsibility for nutritional risk screening and nutritional care planning is primarily assigned to nursing staff, while clinical dietitians are typically involved only following referral.

The ADDUCE trial (A Dietitian-Driven Unified Nutritional Care Model) evaluates an alternative organisational model for delivering hospital nutritional care. The intervention is based on systematic integration of clinical dietitians into ward teams, with dietitians assuming primary responsibility for nutritional risk screening, nutritional assessment, nutritional care planning, and individualised nutritional treatment in close collaboration with nursing staff. Dietitians are present on the wards daily, participate in routine ward activities, and proactively identify patients requiring nutritional care rather than relying solely on referrals.

The study uses a stepped-wedge cluster-randomised controlled design conducted across three medical wards at Gødstrup Hospital, Denmark. All participating wards begin in the control condition, representing current clinical practice. The intervention is then introduced sequentially across wards in a randomised order until all wards have implemented the dietitian-driven model. This design allows each ward to contribute data under both control and intervention conditions while facilitating implementation at ward level.

Approximately 216 participants will be prospectively recruited and enrolled for detailed data collection, including nutritional intake, body weight, nutritional status, quality of life, patient satisfaction, and other clinical and patient-reported outcomes. In addition, routinely collected hospital data from all eligible patients admitted to participating wards during the study period will be used to evaluate length of hospital stay and hospital readmissions. The enrolled cohort will provide detailed clinical information that supports adjusted analyses of secondary outcomes.

The purpose of the study is to determine whether a dietitian-driven model of nutritional care can improve patient outcomes and healthcare efficiency compared with current practice. The study also aims to evaluate whether earlier identification and treatment of patients at nutritional risk can contribute to more systematic nutritional care in hospital settings.

• Dietitian-driven nutritional care model (Behavioral): Clinical dietitians are integrated into the ward team and assume primary responsibility for systematic nutritional risk screening, nutritional assessment, nutritional care planning, follow-up, and nutritional treatment. Dietitians identify patients requiring nutritional care without waiting for referral and collaborate with nursing staff and other clinicians to provide coordinated nutritional care during hospital admission.
• Current practice nutritional care (Other): Nutritional care delivered according to existing ward procedures, with nursing staff primarily responsible for nutritional risk screening and nutritional care planning and clinical dietitians involved following referral or consultation.

Primary outcomes

• Length of hospital stay [Through study completion, an average of 5 days]: Length of hospital stay, defined as the time from hospital admission to hospital discharge. Length of stay will be calculated in hours from electronic health record time stamps and expressed in days (hours/24). Assessed using routinely collected hospital data from all eligible patients admitted to participating wards during the study period.
• Hospital re-admissions [30 days, 90 days]: Number of hospital readmissions after discharge from the index admission, assessed using routinely collected hospital data from all eligible patients admitted to participating wards during the study period.

Secondary outcomes

• Days alive and out of hospital [30 days, 90 days]: Days alive and out of hospital after index admission. Assessed using routinely collected hospital data from all eligible patients admitted to participating wards during the study period.
• Mortality [30 days, 90 days]: Assessed using routinely collected hospital data from all eligible patients admitted to participating wards during the study period.
• Daily energy intake [Day 1-3]: Energy intake (kJ/day) expressed as a percentage of estimated energy requirements, assessed in the prospectively recruited cohort of approximately 216 enrolled participants. Energy intake will be estimated using a 24-hour dietary recall conducted as a structured interview with the participant, supported by data from the hospital electronic meal ordering system and the electronic administration records for enteral and parenteral nutrition.
• Daily protein intake [Day 1-3]: Protein intake (g/day) expressed as a percentage of estimated protein requirements, assessed in the prospectively recruited cohort of approximately 216 enrolled participants. Protein intake will be estimated using a 24-hour dietary recall conducted as a structured interview with the participant, supported by data from the hospital electronic meal ordering system and the electronic administration records for enteral and parenteral nutrition.
• Health-related quality of life (EQ-5D-5L) [Day 2, day 30]: Health-related quality of life assessed using the EQ-5D-5L in the prospectively recruited cohort of approximately 216 enrolled participants. The EQ-5D-5L is a self-administered questionnaire that measures health status across five dimensions and includes a health utility index score. Participants may receive assistance from the data collector if needed. Higher index scores indicate better health-related quality of life.
• Nutritional risk [Day 2, day 30]: Nutritional risk assessed using the Patient-Generated Subjective Global Assessment Short Form (PG-SGA SF) in the prospectively recruited cohort of approximately 216 enrolled participants. The PG-SGA SF is completed by the participant as a self-administered questionnaire, with assistance from the data collector if required to facilitate completion. The questionnaire assesses weight history, food intake, nutrition impact symptoms, and functional capacity. Higher scores indicate greater nutritional risk.
• Nutritional risk screening completed [Throughout study completion, an average of 5 days]: Proportion of eligible patients who undergo nutritional risk screening during hospital admission, assessed using routinely collected hospital data from all eligible patients admitted to participating wards during the study period.
• Nutritional care plan documented [Throughout study completion, an average of 5 days]: Proportion of eligible patients with a documented nutritional care plan during hospital admission, assessed using routinely collected hospital data from all eligible patients admitted to participating wards during the study period.
• Clinical dietitian involvement [Throughout study completion, an average of 5 days]: Proportion of eligible patients with documented involvement of a clinical dietitian during hospital admission, assessed using routinely collected hospital data from all eligible patients admitted to participating wards during the study period.

Sex: All, ages: 18 Years to any

For routinely collected hospital data:

Inclusion Criteria:

* Age 18 years or older
* Admitted to a participating medical ward during the study period
* First eligible admission during the study period

For the prospectively enrolled cohort:

Inclusion Criteria:

* Age 18 years or older
* Newly admitted
* Expected hospital stay until at least day 3 after admission
* Able to speak and understand Danish
* Able to provide written informed consent

Exclusion Criteria:

* Terminally ill patients with short expected survival
* Patients admitted to an isolation room at the time of recruitment

• Marianne Boll Kristensen, RD, PhD, Principal investigator, Department of Nutrition, Gødstrup Hospital