Prevalence of Vitamin D Deficiency in Sickle Cell Disease: A Systematic Review

Abstract

Vitamin D deficiency has emerged as a public health focus in recent years and patients with sickle cell disease (SCD) reportedly have a high prevalence of the condition. Our objectives were to summarize definitions of vitamin D deficiency and insufficiency used in the literature, and to determine the prevalence and magnitude of each in patients with SCD through a systematic review conducted according to PRISMA guidelines. From a PubMed search, 34 potential articles were identified and 15 met eligibility criteria for inclusion. Definitions of deficiency and insufficiency varied greatly across studies making direct comparisons difficult. This review provides evidence to suggest that suboptimal vitamin D levels are highly prevalent among those with SCD, far more so than in comparable non-SCD patients or matched control populations. Defining deficiency as vitamin D <20ng/mL, prevalence estimates in SCD populations range from 56.4% to 96.4%. When compared with results from the population-based National Health and Nutrition Examination Survey, however, the general African American population appeared to have a similarly high prevalence of vitamin D deficiency. African American patients with and without SCD were both substantially higher than that of Caucasians. What remains to be determined is whether there are adverse health effects for patients with SCD because of concurrent vitamin D deficiency.

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

“…Another important finding was that almost half of SCA patients have vitamin D deficiency. These results are in line with those of previous studies on prevalence of vitamin D deficiency among SCA patients which was mentioned in the literature review [19]. Anyhow, previous reports on vitamin D levels in normal population of KSA, indicated that the majority of Saudis have low vitamin D levels mostly due to low dietary intake and sunlight avoidance [26].…”

“…Vitamin D and calcium levels are critical factors for maintaining an optimum healthy bone structure [7]. Due to multiple factors, patients with SCD reported to have higher prevalence of Vitamin D deficiency than normal population, defining deficiency as vitamin D below 20 ng/ml, it ranged from 56.4% to 96.4% [19]. Moreover, they found that patients with bone involvement like AVN and vertebral compression fractures had associated vitamin D deficiency [19].…”

“…Due to multiple factors, patients with SCD reported to have higher prevalence of Vitamin D deficiency than normal population, defining deficiency as vitamin D below 20 ng/ml, it ranged from 56.4% to 96.4% [19]. Moreover, they found that patients with bone involvement like AVN and vertebral compression fractures had associated vitamin D deficiency [19]. Therefore, a randomized double-blind pilot study was conducted recently to determine high-dose vitamin D efficacy in treating chronic pain in patients with SCD [18].…”

Hormonal and echocardiographic abnormalities in adult patients with sickle-cell anemia in Bahrain

“…Another report by showed patients with SCA had low calcium and vitamin D 3 (below the normal range) in 14% and 12%, respectively, with PTH significantly higher (31% with values above normal range) 33. A possible cause of hypocalcemia and vitamin D 3 deficiency is impaired intestinal absorption of calcium and vitamin D, leading to the disturbed calcium metabolism seen in SCA 33,34…”

Nocturnal Enuresis in Children and Adolescent with Sickle cell Anemia

“…Furtheremore, the severity of NE increases as the level of 25(OH) D decreases [133]. Using the same definition in a systematic analysis, the prevalence of vitamin D deficiency was reported to range from 56.4to 96.4% in children with SCA [134].…”