Rheumatoid arthritis disease activity and vitamin D deficiency in an Asian resident population

Aim: We aimed to assess the prevalence of vitamin D deficiency and its association with rheumatoid arthritis (RA) disease activity in a UAE population. Methods: Forty-five consecutive subjects were prospectively recruited during the early summer with their clinical examination and Health Assessment Questionnaire (HAQ) being recorded at a clinic appointment, along with their blood sample being taken for the 25-hydroxyvitamin D (25(OH)D) total test. Results: Thirty-five (76%) patients claimed to be exposed to sunlight for <30 min daily. The prevalence of vitamin D insufficiency (20-30 ng/mL) and deficiency (<20 ng/mL) was 36% and 29%, respectively. RA patients who exposed their hands and feet (29 ng/mL) or more (34 ng/mL) to the sunlight had serum vitamin D levels higher than those who exposed their hands alone (18 ng/mL) or less (19 ng/mL) (P<0.05). The variations in vitamin D levels due to skin color did not reach significance. No significant correlation was seen between serum vitamin D levels and Disease Activity Score (DAS28) or HAQ scores. A direct relationship was observed between HAQ scores and DAS28 scores (P<0.05). Conclusion: We highlight the importance of skin exposure to sunlight in a conservative dressing culture. No association was observed between vitamin D and disease activity. However, the high prevalence of vitamin D deficiency may negatively impact on bone health of these patients in the future.