Vitamin D should be an almost universal feature of the care of young adults with sickle cell disease
Risk factors for vitamin D deficiency in sickle cell disease (study title)
Br J Haematol. 2018 May 16. doi: 10.1111/bjh.15270.
Han J1,2,3, Zhang X2, Saraf SL2, Gowhari M2, Molokie RE2,4, Hassan J2, Jain S2, Shah BN2, Abbasi T2, Machado RF5, Gordeuk VR2.
1 Department of Pharmacy Practice, University of Illinois at Chicago, Chicago, IL, USA.
2 Department of Medicine, Hematology/Oncology, University of Illinois at Chicago, Chicago, IL, USA.
3 Center for Pharmacoepidemiology and Pharmacoeconomic Research, University of Illinois at Chicago, Chicago, IL, USA.
4 Jesse Brown VA Medical Center, Chicago, IL, USA.
5 Division of Pulmonary, Critical Care, Sleep, and Occupational Medicine, Indiana University Department of Medicine, Indianapolis, IN, USA.
Vitamin D deficiency (VDD), 25-OHD levels <20 ng/ml, is prevalent among patients with sickle cell disease (SCD) and is linked to acute and chronic pain and bone fracture in this population. There is limited literature regarding VDD-associated risk factors for SCD.
We examined potential clinical and genomic parameters associated with VDD in 335 adults with SCD in a cross-sectional study. VDD was present in 65% of adult SCD patients, and 25-OHD levels independently and positively correlated with older age (P < 0·001) and vitamin D supplementation (P < 0·001). 25-OHD levels were higher in SCD patients over 40 years of age compared to the general African-American population.
Both lower 25-OHD levels and increased pain frequency were associated with increased expression of SLC6A5 encoding glycine transporter-2 (GlyT2), a protein involved in neuronal pain pathways. Lower 25-OHD levels were also associated with increased expression of CYP3A4, and with decreased expression of GC (also termed DBP) and VDR, three genes involved in vitamin D metabolism.
We conclude that vitamin D supplementation should be an almost universal feature of the care of young adults with SCD, and that further research is warranted into genomic factors that regulate vitamin D metabolism in SCD .