A recent study found that patients with sickle cell disease had lower vitamin D levels compared to healthy controls in Jamaica and West Africa.
Sickle cell disease (SCD) is a hereditary disease that causes red blood cells to have a sickle or crescent shape. The shape prevents the red blood cells from delivering oxygen to the different tissues of the body. SCD also makes red blood cells less flexible causing them to get stuck in blood vessels and block blood flow, which can result in pain and organ damage.
SCD is most common in people with ancestors from Africa, South and Central America, the Caribbean, and Mediterranean countries. Studies from the United States have shown that patients with SCD have lower levels of vitamin D than healthy participants.
Considering that vitamin D deficiency is common in the United States, researchers recently conducted a study to compare vitamin D levels among patients with SCD to those without living in Jamaica and West Africa. Both Jamaica and West Africa are tropical locations that receive abundant sunlight making it easy to produce adequate vitamin D from sun exposure.
The researchers recruited 20 patients from Jamaica and 50 from the West African countries of Nigeria and Ghana who were diagnosed with SCD. They compared them to 459 healthy participants from Jamaica and 497 from West Africa.
They found that average vitamin D levels among patients with SCD was 18.16 ng/ml in Jamaica and 18.6 ng/ml in the West African countries. Whereas, the healthy participants from Jamaica and West Africa had average vitamin D levels of 28.8 ng/ml and 30.36 ng/ml, respectively.
“In conclusion, we have demonstrated that circulating [vitamin D] is lower in patients with SCD from equatorial regions to temperate latitudes,” the researchers stated.
“This finding, which appears to be characteristic of SCD, could offer a window on vitamin D metabolism if the entirety of the metabolic pathway is described.”
The researchers call for large randomized controlled trials to determine if vitamin D supplementation could benefit this patient population.