Changes in serum albumin concentrations over 7 days in medical inpatients with and without nutritional support. A secondary post-hoc analysis of a randomized clinical trial

Background Serum albumin concentrations are frequently used to monitor nutritional therapy in the hospital setting but supporting studies are largely lacking. Within this secondary analysis of a randomized nutritional trial (EFFORT), we assessed whether nutritional support affects short-term changes in serum albumin concentrations and whether an increase in albumin concentration has prognostic implications regarding clinical outcome and response to treatment. Methods We analyzed patients with available serum albumin concentrations at baseline and day 7 included in EFFORT, a Swiss-wide multicenter randomized clinical trial that compared individualized nutritional therapy with usual hospital food (control group). Results Albumin concentrations increased in 320 of 763 (41.9%) included patients (mean age 73.3 years (SD ± 12.9), 53.6% males) with no difference between patients receiving nutritional support and controls. Compared with patients that showed a decrease in albumin concentrations over 7 days, those with an increase had a lower 180-day mortality [74/320 (23.1%) vs. 158/443 (35.7%); adjusted odds ratio 0.63, 95% CI 0.44 to 0.90; p = 0.012] and a shorter length of hospital stay [11.2 ± 7.3 vs. 8.8 ± 5.6 days, adjusted difference −2.2 days (95%CI −3.1 to −1.2)]. Patients with and without a decrease over 7 days had a similar response to nutritional support. Conclusion Results from this secondary analysis indicate that nutritional support did not increase short-term concentrations of albumin over 7 days, and changes in albumin did not correlate with response to nutritional interventions. However, an increase in albumin concentrations possibly mirroring resolution of inflammation was associated with better clinical outcomes. Repeated in-hospital albumin measurements in the short-term is, thus, not indicated for monitoring of patients receiving nutritional support but provides prognostic information. Trail Registration ClinicalTrials.gov Identifier: NCT02517476.


NRS 2002
The Nutritional Risk Screening Score (NRS 2002) is composed of two main parts: impaired nutritional status and severity of disease (≈ stress metabolism), each with a scoring system from 0 (absent) to 3 (severe).Mild impaired nutritional status (Score 1) was defined as weight loss > 5% in 3 months or food intake below 50-75% of normal requirement in the preceding week.Moderate impaired nutritional status (Score 2) was defined as weight loss > 5% in 2 months or BMI < 18.5-20.5kg/m2 plus impaired general condition or food intake of 25-75% of normal requirements in the preceding week.A severe impaired nutritional status means weight loss > 5% in 1 month and weight loss > 15% in 3 months respectively or BMI < 18.5 kg/m2 plus impaired general condition or food intake of 0-25% of requirements in the preceding week.A mild severity of disease (Score 1) was defined as e.g., hip fracture, chronic patients, in particular with acute complications such as cirrhosis or COPD, patients with chronic hemodialysis, diabetes or an oncologic disease.Major abdominal surgery, stroke, severe pneumonia or hematologic malignancy were rated as a moderate severity of disease (Score 2).Head injury, bone marrow transplantation and need of intensive care were considered as severe.This list lacks of completeness.The two scores combined add up to the total score.One has to add 1 score to the total score if age > 70 years to correct for frailty of elderly.An age-corrected total score > 3 indicates "nutritionally at risk" and a nutritional support should be considered. 1

Primary endpoints
-For the prognostic and predictive analyses: 30-day mortality; defined as mortality of all causes from inclusion to day 30 2,3   -For the prognostic analysis only 180-day mortality; defined as mortality of all causes from inclusion to day 180 2,3   -

Secondary endpoints:
-Adverse clinical outcome within 30 days: I.
30-day all-cause mortality: defined as mortality of all causes from inclusion to day 30 2,3

II.
Admission to ICU: defined as transfer to the intensive care unit from hospital ward from admission to day 30 2,3   III.Non-elective hospital readmission after discharge: defined as not intended readmission to hospital after discharge from the index hospitalisation to day 30 2,3   IV.
Major complications: defined as one of the following events from inclusion to day 30: Acute renal failure (two times increase of baseline creatinine or new requirement of dialysis, eg, due to volume overload or electrolyte disturbance) ▪ Nosocomial infection or abscess ▪ Respiratory failure with requiring ventilation (invasive or non-invasive) ▪ Major cardiovascular event including cardiac arrest, myocardial infarction, stroke, intracranial bleeding and pulmonary embolism▪The visual-analogue scale ranks the current health state in a score from 0 to 100 with higher scores indication better health state.2,3,5

Table 1 : Baseline characteristics, additionally stratified by low
C-reactive protein (< 100 g/L) and high C-reactive protein (> 100 g/L) at admission

Table 1 :
Abbreviations : BMI, body mass index (weight in kilograms divided by height in meters squared); NRS, Nutritional risk screening; SD, standard deviation

Loss of function (Barthel index)
a adjusted for age, sex, diagnoses, center
a adjusted for age, sex, diagnoses, center