What is the recommended vitamin D supplementation regimen for hospitalized patients at risk of deficiency?

From the Guidelines

For hospitalized patients at risk of vitamin D deficiency, the recommended supplementation regimen typically involves a loading dose of up to 600,000 IU, followed by maintenance therapy of 800-2000 IU daily, with serum 25-hydroxyvitamin D levels checked at baseline and after 3-6 months to ensure adequate dosing. This approach is based on the most recent and highest quality study available, which emphasizes the importance of individualized dosing and monitoring to ensure effective vitamin D supplementation 1. The study highlights that benefit from vitamin D supplementation can only be expected in deficiency, not in the general population, and that a follow-up vitamin D level should be measured at least once after 3-6 months to ensure adequate dosing.

Key Considerations

• Vitamin D deficiency is defined as a serum/plasma 25(OH)D concentration below 50-75 nmol/L (or 20-30 ng/ml) 1
• Severe vitamin D deficiency is defined as a level below 25 or 30 nmol/L (or 10/12 ng/mL) and increases the risk for osteomalacia and nutritional rickets dramatically 1
• Vitamin D3 or vitamin D2 may be given by the oral, enteral, IV, or IM route, with standard doses taking many weeks to improve/normalize low vitamin D levels 1
• Loading doses are necessary when time is of concern, such as in acutely ill patients or after a fragility fracture, and many regimens have been proposed, including single loading doses of up to 600,000 IU or multiple daily or weekly 50,000 IU doses 1

Recommended Approach

• Use a loading dose of up to 600,000 IU to rapidly correct vitamin D deficiency, followed by maintenance therapy of 800-2000 IU daily 1
• Monitor serum 25-hydroxyvitamin D levels at baseline and after 3-6 months to ensure adequate dosing and adjust the regimen as needed 1
• Consider individualized dosing based on genetic variations in vitamin D metabolism and other factors that may affect response to supplementation 1

From the Research

Vitamin D Supplementation in Hospitalized Patients

• The recommended vitamin D supplementation regimen for hospitalized patients at risk of deficiency is not universally established, but several studies provide guidance on this topic 2, 3, 4, 5, 6.
• According to the American Academy of Pediatrics, infants and children should receive at least 400 IU per day from diet and supplements to prevent vitamin D deficiency 2.
• For adults, evidence shows that vitamin D supplementation of at least 700 to 800 IU per day reduces fracture and fall rates 2.
• In patients with vitamin D deficiency, treatment may include oral ergocalciferol (vitamin D2) at 50,000 IU per week for eight weeks, followed by maintenance dosages of cholecalciferol (vitamin D3) at 800 to 1,000 IU per day from dietary and supplemental sources 2.
• The Institute of Medicine recommends that most North Americans receive sufficient vitamin D from their diet and sun exposure, but some clinical practice guidelines suggest that supplementation may be necessary for certain populations 4.

Diagnosis and Treatment of Vitamin D Deficiency

• Vitamin D deficiency is defined as a serum 25-hydroxyvitamin D level of less than 20 ng per mL (50 nmol per L), and insufficiency is defined as a serum 25-hydroxyvitamin D level of 20 to 30 ng per mL (50 to 75 nmol per L) 2, 4, 6.
• The National Osteoporosis Society recommends measuring serum 25(OH) vitamin D to estimate vitamin D status in patients with bone diseases or musculoskeletal symptoms that could be attributed to vitamin D deficiency 6.
• Treatment of vitamin D deficiency may involve oral vitamin D3 with fixed loading doses followed by regular maintenance therapy, although loading doses are not necessary in all cases 6.

Special Considerations

• Elderly hospitalized patients with ionized hypocalcemia and hypophosphatemia, with or without an elevated parathyroid hormone level, are most likely deficient in vitamin D 3.
• Patients with severe femoral neck or intertrochanteric fractures are more likely to have vitamin D deficiency and may benefit from supplementation 5.
• Routine monitoring of serum 25OHD is generally unnecessary, but may be appropriate in patients with symptomatic vitamin D deficiency or malabsorption 6.