Sickle cell bone disease: Response to vitamin D and calcium

Abstract

Bone disease with osteoporosis and osteomalacia are common in sickle cell disease (SCD). Some patients have vitamin D deficiency and low bone mineral density (BMD). The role of vitamin D and calcium supplementation to restore bone health in SCD has not been well studied. In 14 adults with SCD, we measured 25(OH)D (25-hydroxyvitamin D) and BMD at the femoral neck, lumbar spine, and distal third of the ulna plus radius, along with markers of bone resorption (CTx; C-terminal component of pro-collagen type I) and bone formation (osteocalcin) before and after 12 months of vitamin D 2 and calcium carbonate treatment. Pretreatment, all patients were vitamin D deficient with a mean 25(OH)D level of 10.7 ± 4.7 ng/ml, had low BMD at the lumbar spine (L-spine), 0.87 ± 0.11 g/cm 2 (mean Z-score of -2.6 3 ± 0.71 SD and T score of -2.31 ± 0.75 SD), femoral neck, 0.8 ± 0.18 g/cm 2 (mean Z-score -1.36 ± 0.84, T-score -1.14 ± 0.75), and the distal radius and ulna, 0.6 ± 0.17 g/cm 2 (mean Z-score -1.18 ± 0.79, T-score -1.01 ± 0.74) and had elevated CTx (0.87 ± 0.5 ng/ml) and osteocalcin levels (12.3 ± 3.7 ng/ll). After treatment, all patients corrected their 25(OH)D level (38.8 ± 13.9 ng/ml) (P < 0.001) with a 3.6% ± 3.9% increase in BMD at the L-spine (P 5 0.009), 4.6% ± 8.5% increase at the femoral neck (P 5 0.05) and 6.5% ± 12.6% increase at the distal radius plus ulna (P 5 0.09). CTx, osteocalcin, and PTH(i) levels were unchanged. Treatment of adult SCD with vitamin D and calcium can restore 25(OH)D levels to normal and improve BMD, but, markers of bone resorption remained unchanged. Screening for vitamin D deficiency and BMD in SCD patients seems warranted. Am. J. Hematol. 83:271-274, 2008. V

The Prevalence of Avascular Necrosis in Adults With Sickle Cell Disease in King Fahad Hospital.

“…While 13.4% of SCA patients have low serum calcium levels. These results match those observed in earlier studies on SCA patients in KSA and USA [26,27]. A possible explanation for this might be that SCA patients have hypocalcemia tendency due to multiple factors like poor intestinal absorption of calcium and vitamin D, which stimulate PTH secretion that might contribute to the skeletal changes seen in SCA patients [26].…”

Bone Disease in Haemoglobin Disorders

“…Several factors, including reduced haemoglobin levels, chronic haemolytic anaemia, hyperplasia of the bone marrow, abnor- mally low body mass index (BMI), increased ferritin levels, vitamin D deficiencies and low plasma zinc or sex steroid levels, have been previously correlated with reduced BMD in adult patients with SCD (17)(18)(19). Furthermore, reduced physical activity and decreased circulating GH are likely contributing factors (20,21).…”

Iron and Menopause: Does Increased Iron Affect the Health of Postmenopausal Women?

“…Sickle cell disease, an inherited disorder accompanied by anemia and iron overload because of defective hemoglobin, often leads to osteoporosis and osteopenia (2,35). Analyses of sickle cell disease patients showed that low bone mineral density was significantly associated with lower body mass index, lower hemoglobin, and higher ferritin levels (35).…”