Evaluation of an Integrated Nutrition, Volume, and Electrolyte Nursing Protocol in Elderly Diabetic Nephropathy: A Retrospective Cohort Study

Summary

This retrospective historical-control study evaluated an integrated nutrition, volume, and electrolyte nursing protocol in 66 elderly patients with diabetic nephropathy. Compared with routine nursing, the protocol was associated with more favorable nutritional, volume, electrolyte, renal-function, adverse-event, quality-of-life, and economic indicators during hospitalization and three-month follow-up.

Abstract

To develop a “nutrition-volume-electrolyte” Trinity nursing protocol for elderly patients with diabetic nephropathy (DN), centered on precise nutritional protein regulation, and to evaluate its clinical and economic value. This single-center retrospective cohort study included 66 elderly patients with DN admitted between January 2022 and November 2025. Based on the implementation of the updated nursing protocol in January 2024, 31 patients who received routine nursing care were assigned to the historical control group, and 35 patients who received Trinity integrated nursing based on stratified nutritional protein management combined with volume and electrolyte regulation were assigned to the observation group. Interventions were delivered during hospitalization and continued for three months after discharge. Outcomes included nutritional indicators, volume load, electrolyte target attainment, renal function, adverse events, quality of life, and health economic measures. After three months, albumin, prealbumin, hemoglobin, and transferrin were significantly higher in the observation group than in the control group (all P < 0.01). At all assessed time points, the 24-h intake-output difference, B-type natriuretic peptide (BNP) level, and edema severity score were lower in the observation group (all P < 0.001). Target attainment rates for serum potassium, sodium, calcium, and phosphorus were higher (all P < 0.05), and changes in eGFR, serum creatinine, and 24-h urinary total protein were more favorable (all P < 0.05). Adverse events were less frequent in the observation group than in the control group (25.71% vs. 51.61%, P = 0.030). 36-Item Short Form Health Survey (SF-36) scores were higher, whereas hospital stay, total medical cost per capita, and cost per unit effect were lower (all P. < 0.001). In conclusion, the Trinity integrated nursing protocol improved nutritional status, volume, and electrolyte balance, renal outcomes, quality of life, and economic performance in elderly patients with DN, supporting its value in clinical nursing management.

Introduction

With the ongoing aging of the global population, diabetic nephropathy (DN) in older adults has become an increasingly important issue in the prevention and management of chronic disease in the elderly¹. Epidemiologic studies indicate that type 2 diabetes and chronic kidney disease frequently coexist in older adults, and diabetes remains a major contributor to kidney failure requiring dialysis or transplantation². In elderly patients, damage to the glomerular filtration barrier and persistent proteinuria lead to continuous loss of key nutritional proteins such as albumin. At the same time, age-related decline in organ fun....

Protocol

This study was approved by the Ethics Committee of Zhejiang University School of Medicine. Because the study involved only anonymized retrospective data and no direct patient contact, informed consent was waived. The reagents and the equipment used are listed in the Table of Materials.

Study design and patient screening
This study used a single-center retrospective cohort design; elderly patients with DN who were treated in Zhejiang University School of Medicine between January 2022 and November 2025 were included. Candidate records were first identified through the hospital information system accordi....

Results

Comparison of baseline characteristics
Baseline demographic characteristics, disease status, complications, and laboratory indicators at admission were compared between the two groups. No statistically significant differences were found in baseline variables (P. > 0.05, Table 1).

Changes in nutritional protein-related indicators before and after intervention
After three months, ALB, PA, HGB, and TRF were all higher in the o.......

Discussion

In routine nursing practice, nutrition, volume status, and electrolyte balance in elderly patients with DN are often managed as separate issues rather than as closely related components of the same clinical problem. In the present study, the Trinity nursing protocol was associated with more favorable outcomes than routine care across several dimensions. Patients in the observation group showed better nutritional indices, more stable volume and electrolyte status, slower deterioration in renal function, fewer adverse even.......

Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
Centrifuge	Hunan Xiangyi Laboratory Instrument Development Co., Ltd.	TGL-16G	Routine high-speed centrifuge for laboratory use, used for centrifuging collected venous blood at 3000 r/min for 10 minutes to separate serum from blood components, providing serum samples for subsequent blood index testing.
24-hour Urinary Total Protein (24-h UTP) Detection Reagent	Shanghai Kehua Bio-Engineering Co., Ltd.	KHB Series Matching Biochemical Reagent	Used for detecting total protein content in 24-hour urine, directly reflecting the degree of proteinuria in patients, and serving as an important indicator for evaluating renal injury and renal function changes in patients with diabetic nephropathy.
Bicarbonate Detection Reagent	Mindray Biomedical Electronics Co., Ltd.	BS-800 Series Matching Biochemical Reagent	Used for detecting bicarbonate content in serum, serving as an auxiliary indicator for acid-base balance and electrolytes, and participating in the evaluation of patients' electrolyte and internal environment balance.
B-type Natriuretic Peptide (BNP) Detection Reagent	Abbott Diagnostics Products (Shanghai) Co., Ltd.	i2000 Series Matching Chemiluminescence Reagent	Used for detecting BNP concentration in serum, serving as a key indicator for evaluating the volume load of research subjects and assisting in judging volume abnormalities related to edema and cardiac function.
Disposable Blood Collection Needle	Becton, Dickinson and Company (BD) Medical Devices (Shanghai) Co., Ltd.	21G	Used in conjunction with vacuum blood collection tubes for venipuncture of the cubital vein to collect venous blood. The needle size is suitable for venous blood collection operations, and single-use ensures sterility.
Hemoglobin (HGB) Detection Reagent	Sysmex Medical Electronics (Shanghai) Co., Ltd.	XN Series Matching Hematology Reagent	Used for detecting hemoglobin content in blood, comprehensively evaluating the nutritional status of research subjects in combination with indicators such as albumin and prealbumin, and serving as an important reagent for anemia and nutritional assessment.
Prealbumin (PA) Detection Reagent	Roche Diagnostics Products (Shanghai) Co., Ltd.	cobas c Series Matching Biochemical Reagent	Used in conjunction with albumin detection reagents to detect prealbumin levels in serum, assisting in evaluating the short-term nutritional status of patients and providing monitoring indicators for the effectiveness of nutritional interventions.
Serum Albumin (ALB) Detection Reagent	Roche Diagnostics Products (Shanghai) Co., Ltd.	cobas c Series Matching Biochemical Reagent	Used for detecting albumin content in serum, serving as a core reagent for evaluating the nutritional protein status of research subjects. Suitable for fully automatic biochemical analyzers, the test results provide data for evaluating the nutritional status of elderly patients with diabetic nephropathy.
Serum Creatinine (Scr) Detection Reagent	Roche Diagnostics Products (Shanghai) Co., Ltd.	cobas c Series Matching Biochemical Reagent	Detects creatinine concentration in serum, serving as one of the core indicators for evaluating renal function. Combined with eGFR and 24h urinary total protein, it judges the degree of renal injury and intervention effect in patients.
Serum Electrolyte Detection Reagent (Potassium, Sodium, Calcium, Phosphorus)	Mindray Biomedical Electronics Co., Ltd.	BS-800 Series Matching Biochemical Reagent	Contains dedicated reagents for detecting potassium, sodium, calcium, and phosphorus ions, used for detecting the concentration of corresponding electrolytes in serum, calculating the electrolyte target compliance rate, and evaluating electrolyte balance status.
SPSS Statistical Software	IBM Corporation	SPSS 26.0	Used for statistical analysis of all clinical and experimental data in this study, capable of completing various statistical methods such as independent sample t-test, paired t-test, chi-square test, and Mann-Whitney U test, with α=0.05 set as the statistical significance criterion.
Transferrin (TRF) Detection Reagent	Roche Diagnostics Products (Shanghai) Co., Ltd.	cobas c Series Matching Biochemical Reagent	Detects transferrin levels in serum, serving as one of the nutritional protein-related indicators to participate in the comprehensive evaluation of patients' nutritional status, reflecting the body's iron metabolism and nutritional reserves.
Vacuum Coagulation-promoting Blood Collection Tube	Becton, Dickinson and Company (BD) Medical Devices (Shanghai) Co., Ltd.	3ml Routine Coagulation-promoting Type	Used for collecting fasting venous blood from the cubital vein of research subjects, with a single tube blood collection volume of 3ml. Coagulants accelerate blood coagulation to facilitate subsequent serum separation, serving as a dedicated device for blood sample collection.