Low albumin levels could predict poor outcome in COVID-19

By Dr. Ananya Mandal, MDMay 13 2020

A Spanish study has revealed that COVID-19 patients who have a low level of albumin have a poorer outcome compared to those with normal levels of blood albumin. The study titled, “Low albumin levels are associated with poorer outcomes in a case series of COVID-19 patients in Spain: a retrospective cohort study,” was released prior to peer-review on the open-access preprint server site Medrxiv*.

Study: Low albumin levels are associated with poorer outcomes in a case series of COVID-19 patients in Spain: a retrospective cohort study. Image Credit: Jarun Ontakrai Shutterstock

This news article was a review of a preliminary scientific report that had not undergone peer-review at the time of publication. Since its initial publication, the scientific report has now been peer reviewed and accepted for publication in a Scientific Journal. Links to the preliminary and peer-reviewed reports are available in the Sources section at the bottom of this article. View Sources

What was this study about?

Researchers led by Dr. Roberto de la Rica and others collaborating from the Multidisciplinary Sepsis Group, Health Research Institute of the Balearic Islands, Son Llatzer University Hospital, Cardiopulmonary Pathology Of the Critically Ill Patient Group, Health Research Institute of the Balearic Islands and the Vascular and Metabolic Pathologies Group, Health Research Institute of the Balearic Islands, performed this retrospective cohort study.

The COVID-19 pandemic has claimed nearly three hundred thousand lives across the world, and Spain has been one of the most severely affected nations. The authors of the study write that when they finished writing the research paper there had been already over 25,000 deaths due to COVID-19 in Spain. They explain that despite this, there is little information regarding the underlying features and risk factors of the patients who are at risk of worsening symptoms and hospitalization due to the infection. This was a small case series where 48 patients admitted with COVID-19 were studied.

The researchers explained that it was needed to understand the factors that characterize a patient who may have a poor outcome or poor prognosis due to the infection. They wrote that if they could identify the factors that led to a poor prognosis in the patients at an early stage before the situation worsens and becomes irreversible, the patients could be saved using necessary measures. The team said that many studies show that there is an overwhelming of the immune system during the infection. This could be the key factor that leads to the progress of a mild infection to a more severe and ultimately critical and life-threatening state of the patient. They wrote that since inflammation played a key role, factors that influence inflammation could play an important role in the progression of the disease.

Albumin is a protein made in the liver and is detected in the blood. This protein in the blood prevents leakage of the fluids from the blood into other tissues. Those with low albumin may have problems in their liver and kidneys. Low albumin is also seen in patients with malnutrition, severe infection, thyroid disease, and inflammatory bowel disease.

What was done?

This was a small scale study made up of 52 patients hospitalized due to complications of COVID-19 up to 31^st March 2020. Of these patients, 48 had severe acute respiratory syndrome due to SARS-CoV-2. They all had tested positive for the virus. Data was gathered between the 15^th and 31^st of March 2020 from the Son Llatzer University Hospital in Palma de Mallorca (Spain). The objective of the study was to “describe the clinical characteristics and epidemiological features of severe (non-ICU) and critically patients (ICU) with COVID-19 at triage, prior hospitalization.”

The researchers gathered data such as vital signs of the patients, clinical features, laboratory reports, and symptoms present before hospitalization, age, and other demographic parameters of the patients. At the end of the study, deaths among the participants were recorded.

What was found?

In this study of 48 patients, 21 were admitted into intensive care (ICU), and 27 were not. These patients were all residents of the island of Mallorca in Spain. Their average age was 66 years, and 67 percent of them were male. Age distribution was similar among the patients. Findings were as follows;

• The symptoms prior to hospitalization included fever (in all patients), cough (in 85 percent patients), difficulty in breathing (in 76 percent patients), diarrhea (42 percent patients, and weakness (21 percent).
• The main reason for hospitalization among the patients was low blood oxygen (low SpO2 below 90 percent) and the presence of pneumonia in both lungs. Pneumonia in both lungs was seen in 94 percent of cases.
• Among the patients, 70 percent had high blood pressure, 62 percent had raised cholesterol, and 30 percent had heart disease.
• Those admitted to the ICU had a higher presence of difficulty in breathing compared to non-ICU patients (95 percent among ICU patients and 61 percent among non-ICU patients).
• Acute respiratory syndrome (ARDS) developed in all patients admitted to the ICU.
• All 48 participants needed oxygen therapy
• Lab reports showed that ICU patients had low lymphocyte counts and low levels of blood albumin.
• Among patients admitted to the ICU, there was a significant rise in markers of inflammation such as “lactate dehydrogenase (LDH), C-reactive protein (CRP), and procalcitonin,” when compared to those, not in ICU.
• Lower levels of blood albumin were significantly associated with poorer outcome and a longer stay in the hospital. The risk of death was also higher among those with lower levels of albumin in their blood.
• When red blood cells were examined, the mean corpuscular volume of the RBCs was found to be lower among patients who died of the infection and its complications.
• Until the end of the study (28^th April 2020), there was a 21 percent case fatality seen in the study with eight patients in ICU and 2 in non-ICU set up succumbing to the infection.
• At the end of the study, all the non-ICU patients were discharged and allowed to leave the hospital. While among the ICU patients, one third remained in the hospital at the end of the study with 5 in ICU and 2 transferred to the general wards.

Conclusions and implications

The team wrote that those with influenza A (H1N1) and human immunodeficiency virus infection (HIV) have also been seen to have a poorer outcome if they had lower levels of albumin. Among influenza patients need for respiratory support rose with low albumin levels, and among HIV patients, low albumin meant a greater risk of inflammation, coagulability, and atherosclerosis, they wrote. Albumin in blood also protected against the Ebola infection they wrote.

The authors wrote that this was a relatively small study that showed that certain lab features might be important in the characterization of severity in COVID-19 patients. They wrote, “Lower levels of albumin were associated with poorer outcomes in COVID-19 patients. Albumin might be of importance because of its association with disease severity and mortality in patients infected with SARS-CoV-2.” They added, “This small case series provides the first steps towards a comprehensive clinical characterization of severe and critical COVID-19 adult patients in Spain.”

This news article was a review of a preliminary scientific report that had not undergone peer-review at the time of publication. Since its initial publication, the scientific report has now been peer reviewed and accepted for publication in a Scientific Journal. Links to the preliminary and peer-reviewed reports are available in the Sources section at the bottom of this article. View Sources