The Albumin and Prealbumin Conundrum: Why Other Tools are Better Suited for Malnutrition Diagnosis
By Samir Hussaini, MD
The Albumin and Prealbumin Conundrum
Why Other Tools are Better Suited for Malnutrition Diagnosis
Malnutrition can double the length of stay of hospitalized malnourished patients compared to non-malnourished patients, and can be a complicated condition to diagnose. Without a widely accepted way to monitor and diagnose this condition, there has previously been too much emphasis on traditional laboratory markers, specifically albumin and prealbumin. Unfortunately, serum albumin and prealbumin may not be the most direct measure of nutritional status for malnutrition diagnosis. A better solution would be a nutrition-focused physical exam(NFPE) with vital input from registered dietitians to help diagnose malnutrition, a solution that can be easily facilitated with MalnutritionCDS™ software from Junum.
The start of albumin and prealbumin and its role in inflammation
The use of serum albumin to describe malnutrition was first written by Blackburn et al in 1977¹. Around that time, it was used as an instant assessment to identify those that would benefit from significant nutritional support. In 1995, prealbumin was seen as a more sensitive biomarker to measure nutrition and a patient’s response to nutritional support². This led to a 40-year old practice of using serum albumin and later prealbumin to identify malnutrition, but unfortunately this may not be the best marker for nutritional status.
While inflammation is a potential etiology of malnutrition, albumin and prealbumin are better measures for inflammation and are inappropriately used to measure direct nutritional status and to diagnose malnutrition. Davis et al found that there was no significant difference in change of serum prealbumin despite changes in protein and energy intake³. The only cause of change in serum prealbumin was an increase in C-reactive protein(CRP), a serum biomarker used to describe inflammation.
The sticky relationship between albumin and prealbumin with body composition
Serum albumin and prealbumin can be incorrectly used as proxy for measurement of muscle mass and body composition. It is understandably assumed that as one’s BMI decreases from malnutrition the serum albumin and prealbumin would drop as well. However, a study shows that decrease in serum albumin and prealbumin is seen once the patient reaches below a BMI of 12 while having six weeks or more of starvation⁴. It isn’t as straightforward as it seems.
Better tools to diagnose malnutrition
To better diagnose malnutrition, there are more accurate tools than solely using serum albumin and prealbumin. The recommended approach being the Academy of Nutrition and Dietetics and American Society of Parenteral and Enteral Nutrition (Academy-ASPEN) criteria, a comprehensive methodology being validated to diagnose malnutrition in the hospital setting⁵. This criteria does not take into account just serum albumin and prealbumin, but energy intake, weight loss, body fat, muscle mass, fluid accumulation, and grip strength. Some examples of what dietitians look for include:
- Eating less than 50% of estimated energy requirements for more than 5 days
- Noticeable muscle loss around the temple of the head
- Swelling of the lower legs
The best way to do this in the hospital setting is to include the registered dietitians in your treatment plan. The dietitians are the experts in understanding patient nutritional status and are the most qualified to use the Academy-ASPEN criteria in the process to diagnose malnutrition. Junum’s MalnutritionCDS™ software is the optimal solution in assisting dietitians to accurately record malnutrition in the hospital setting and give patients the best care they can.