Vitamin D deficiency in sickle cell disease patients in the Eastern Province of Saudi Arabia.

BACKGROUND

Vitamin D deficiency (VDD) is a major global health problem. In sickle cell disease (SCD), VDD is highly prevalent, reaching up to 96% of populations. VDD may contribute to many of the complications of SCD.

OBJECTIVE

Estimate the 25-hydroxyvitamin D [25(OH)D] level and the frequency of VDD and insufficiency among among SCD patients by age group and disease status.

DESIGN

Analytical cross-sectional.

SETTING

Ministry of Health (MOH) secondary care hospital.

PATIENTS AND METHODS

Non-probability purposive sampling was used to select SCD patients, aged 12 years and older, of both sexes, who had visited the hospital during a period of 5 years (2010-2014). Blood samples were processed by electrochemiluminescence technology.

MAIN OUTCOME MEASURE(S): 25(OH)D levels by demographic data, and disease activity.

SAMPLE SIZE

640 patients.

RESULTS

Of those, 82% (n=523) had suboptimal 25(OH)D (0-<30 ng/ mL), and 67% were deficient (0-<20 ng/mL). Patients with any SCD crisis (20.7%, 144/694) had lower 25(OH)D (median, IQR: 10.1 ng/mL [8.6] ng/mL) compared to patients without crisis (71.0%, 493/694) (15.7 ng/ mL [18.2] ng/mL) (P<.001). Deficiency was more common in the young.er age groups and in sickle cell anemia patients with crisis.

CONCLUSIONS

VDD is highly prevalent in this population. Established vitamin D screening is a necessity, so that affected patients can be treated.

LIMITATIONS

Presence of residual confounders such as nutritional status, physical activity, lack of sun exposure, medications that alleviate SCD crises (such as hydroxyurea), and comorbid illnesses. The relationship between sickle cell disease genotype and vitamin D level was not analyzed.

CONFLICT OF INTEREST

None.