What electrolyte imbalance is most commonly associated with refeeding syndrome: hypocalcemia, hypophosphatemia, hypokalemia, or hyponatremia?

From the Guidelines

Refeeding syndrome is most commonly related to hypophosphatemia (option c). This potentially life-threatening condition occurs when nutritional support is reintroduced too rapidly in malnourished patients. During starvation, the body depletes intracellular phosphate stores, and when refeeding begins, insulin secretion increases, driving glucose, phosphate, potassium, and magnesium into cells. This cellular uptake leads to a profound drop in serum phosphate levels. Hypophosphatemia is the hallmark electrolyte abnormality in refeeding syndrome and can cause cardiac arrhythmias, respiratory failure, seizures, and even death. While hypokalemia, hypomagnesemia, and fluid shifts also occur in refeeding syndrome, hypophosphatemia is the most characteristic and dangerous feature, as stated in the ESPEN guidelines on nutrition in cancer patients 1 and the ESPEN guidelines on definitions and terminology of clinical nutrition 1.

Some key points to consider in the management of refeeding syndrome include:

• Monitoring electrolytes, especially phosphate, and appropriate supplementation as needed
• Starting nutritional rehabilitation slowly, with no more than half of the calculated energy requirements supplied during the first 2 days of feeding 1
• Screening for patients at risk of refeeding syndrome, including those with a BMI <16 kg/m2, unintentional weight loss >15% in 3-6 months, or little or no intake for >10 days 1
• Providing vitamin B1 in daily doses of 200-300 mg, as well as a balanced micronutrient mixture, to prevent complications such as thiamine deficiency 1.

Overall, the prevention and management of refeeding syndrome require careful attention to electrolyte balance, nutritional support, and monitoring for potential complications, with a focus on preventing hypophosphatemia and its associated morbidity and mortality.

From the Research

Refeeding Syndrome

Refeeding syndrome is a condition that occurs in malnourished patients when they are reintroduced to nutrition, leading to various metabolic complications. The most common electrolyte imbalance associated with refeeding syndrome is:

• Hypophosphatemia, as stated in studies 2, 3, 4, 5, 6

Electrolyte Imbalances

Other electrolyte imbalances that may occur in refeeding syndrome include:

• Hypokalemia, as mentioned in studies 3, 5, 6
• Hyponatremia, as mentioned in studies 3, 5
• Hypocalcemia, as mentioned in studies 3, 5 However, hypophosphatemia is the most significant and well-known element of refeeding syndrome, as stated in study 4

Clinical Significance

Refeeding syndrome can lead to severe complications, including:

• Sudden death, as mentioned in study 4
• Rhabdomyolysis, as mentioned in study 4
• Red cell dysfunction, as mentioned in study 4
• Respiratory insufficiency, as mentioned in study 4 It is essential to recognize and prevent refeeding syndrome, as stated in study 2