Abstract

Introduction: Prealbumin is a protein synthesized by the choroid plexus and liver, playing integral roles in the transport of thyroxine and retinol. Its serum levels are known to decrease in response to conditions such as inflammation, protein deficiency, end-stage liver disease, and malignancy. Notably, decreased serum prealbumin levels have been negatively correlated with the severity of stroke. Given this context, understanding factors that predict functional outcomes and mortality in stroke patients is crucial, particularly the potential role of nutritional status and prealbumin levels.

Methods: This study targeted a patient population aged 18 to 100 years who were treated for stroke. We systematically recorded levels of prealbumin, albumin, hemoglobin, and the BUN/Cre ratio at three time intervals: on admission, the 5th day, and the 9th day post-admission. In addition, we assessed the severity and functional outcomes using the NIHSS and mRS scores at admission, the 9th day, and upon discharge. Other recorded parameters included Body Mass Index (BMI), daily caloric requirements, NRS-2002 nutritional risk screening scores, chronic disease presence, length of hospital stay, history of infarction, TOAST classification, and dietary patterns. Our study included a total of 57 patients.

Results: Our findings indicate that there was no significant difference in age between nonsurviving and surviving stroke patients, although deceased patients tended to be older. Notably, prealbumin and albumin levels were significantly higher in surviving patients (p < 0.05). The BUN/Cre ratio showed no difference between the groups at the time of admission, but its values on the 5th and 9th days were significantly elevated in nonsurvivors (p < 0.01). Furthermore, our analysis revealed that an increase in prealbumin and albumin levels positively influenced patient outcomes. Conversely, higher BUN/Cre ratios and NIHSS scores were associated with poor outcomes, with these differences reaching statistical significance (p < 0.01).

Conclusion: The study established a clear association between prealbumin and albumin levels, the BUN/Cre ratio, NIHSS and mRS scores, and overall nutritional status with the functional outcomes and mortality rates in stroke patients. Our results underscore the importance of closely monitoring nutritional status and these specific biochemical markers as part of the comprehensive management of stroke patients to potentially improve their outcomes.

Introduction

In developed countries, stroke mortality ranks after ischemic heart disease and cancer1. Malnutrition represents a significant, preventable consequence impacting many stroke victims, typically defined as a protein-energy deficiency. It was reported in 16.3% of patients hospitalized with acute stroke, with this rate increasing to 26.4% by day 72. Malnutrition is associated with fatigue, muscle weakness, and the loss of muscle mass. Additionally, it causes immunosuppression, impaired intestinal function, and hospital infections3. After a stroke, levels of plasma cortisol, catecholamines, interleukins, and glucagon, along with acute phase reactants, increase as part of the acute stress response, leading to the rapid loss of muscle mass4. It has been demonstrated that just ten days of bed rest can result in a 30% decrease in muscle protein synthesis and a 6% reduction in leg muscle mass, culminating in a 16% loss of muscle strength in healthy older adults5.

Prealbumin is a protein primarily synthesized by the choroid plexus and liver, involved in the transport of thyroxine and retinol. Decreases in serum prealbumin levels, which negatively correlate with stroke severity, can be caused by inflammation, protein deficiency, end-stage liver disease, and malignancy6, 7. As it is a negative acute-phase reactant, serum concentrations of prealbumin decrease rapidly due to reduced mRNA expression8. Malnutrition is expected to occur in the acute phase of a stroke. Initial malnutrition may lead to more complications post-stroke, and it has been reported that malnutrition in the first week predicts poor outcomes for three months9. Therefore, nutritional assessment upon hospital admission and the early identification of patients at risk of malnutrition may be necessary for effective treatment. This study aimed to investigate whether the nutritional status, dietary pattern, and prealbumin levels can predict functional outcomes and mortality in stroke patients.

Methods

After obtaining approval, patients aged 18 to 100 years who were treated in the hospital for a stroke were included in the study. Patients were followed and observed for at least 10 days until discharge or death, and laboratory findings and scores were recorded. Informed consent was obtained from all patients or their relatives. In addition, prealbumin, albumin, hemoglobin, and BUN/Cre ratio were recorded on days 0, 5, and 9. The National Institutes of Health Stroke Scale (NIHSS) score and the modified Rankin scale (mRS) score were recorded on admission, on the 9th day, and at discharge. Body mass index (BMI), daily caloric requirements, chronic diseases, length of hospital stay, history of infarction, Trial of Org 10172 in Acute Stroke Treatment (TOAST) classification, dietary pattern, and nutritional risk screening (NRS-2002) scores were also recorded. Oral feeding was preferred when possible, and in patients with poor swallowing function, a nasogastric catheter was placed, and enteral nutrition was started. For patients who could not tolerate enteral nutrition, parenteral nutrition was preferred. Patients who died within ten days after hospitalization, were transferred to the intensive care unit, had liver failure or chronic renal failure, had intracranial hemorrhage, or who experienced further complications were excluded from the study.

TOAST Classification

According to this classification, patients are divided into five subtypes:

a. large artery atherosclerosis, b. cardioembolism, c. small vessel occlusion, d. other determined etiologies, and e. undetermined etiologies NIHSS

The NIHSS, a systematic assessment tool measuring the most common neurological deficits in acute stroke patients, includes assessments of the level of consciousness, gaze, visual field, visual impairment, motor performance of the extremities, sensory deficits, coordination (ataxia), speech (aphasia), and language (dysarthria), and assesses semiattention (neglect). The scale was created for rapid assessment of neurological function in the early post-stroke period. "A score of 0 is considered normal for all parameters, so the higher the score, the worse the neurological deficit (the highest possible score is 42)."

mRS

The mRS, used in the follow-up of stroke patients, is a scale that determines the severity of stroke and is used to identify dependency and assess functional improvement (Table 1). According to this scale, those who score 1 or 2 can continue to live independently, and those who score 3 or more can continue to live as dependents.

Table 1.

The Modified Rankin Scale (mRS)

Grade 0 1 2 3 4 5 6 Desription No symptoms at all No significant disability despite symptoms: able to carry out all usual duties and activities Slight disability: unable to carry out all previous activities but able to look after own affairs without assistance Moderate disability: requiring some help, but able to walk without assistance Moderately severe disability: unable to walk without assistance, and unable to attend to own bodily needs Severe disability: bedridden, incontinent, and requiring constant nursing care and attention Death NRS-2002

The NRS-2002 scoreboard comprises three parts: disease severity, nutritional status, and age. Scores ≥3 points indicate the presence of nutritional risk and the need for nutritional therapy.

Statistical Analyses

The results are expressed as percentages for categorical variables, means for normally distributed variables, and medians (interquartile ranges) for non-normally distributed continuous variables. Continuous variables were compared using t-tests and Mann–Whitney tests, while categorical variables were compared using chi-square tests. Correlations between continuous variables were assessed with Pearson's or Spearman's rank correlation coefficient, depending on distribution status. The severity of the cerebrovascular event was classified as "no or mild (mRS score 0-2: no or only mild neurological symptoms) or severe (mRS score 3-6: moderate or severe disability)" based on the mRS score on day 9. A logistic regression model was used to examine the relationships between the measured parameters, mortality, and high mRS score. Adjusted univariate and multivariate models and reported odds ratios (ORs) and 95% confidence intervals (CIs) were used for all major outcome predictors. A binary logistic regression model that included hypertension, diabetes mellitus, history of stroke, atrial fibrillation, and TOAST subtype was used to examine the ability of these variables to predict the group status. Analyses were performed using the SPSS software package (version 26.0), and p

Ethical Principles

The study was carried out in accordance with the Helsinki Declaration of 1975. The ethics committee approval number is Erzurum City Hospital, Erzurum, Turkey (Date: 20.06.2022 No: 2022/08-95).

Table 2.

Baseline characteristics of study population

N Survivor Non-survivor p-value Age (Mean ± SD) 75.42 ± 12.75 74.08 ± 10.15 77.9 ± 16.55 0.35 Male/Female 114 (58/56) 74 (34/40) 40 (24/16) 0.31 BMI 26.78 ± 3.78 26.66 ± 4.0 25.87 ± 3.1 0.84 NRS-2002 3.65 ± 1.3 3.73 ± 1.36 3.5 ± 1.23 0.52 Prealbumin 0 th day (Mean ± SD) 0.15 ± 0.06 0.16 ± 0.06 0.13 ± 0.07 0.04 Prealbumin 5 th day (Mean ± SD) 0.12 ± 0.06