Serum Vitamin D and Anti-Cyclic Citrullinated Peptide Levels in Rheumatoid Arthritis Patients

Abstract

Background: Rheumatoid arthritis (RA) is long-term autoimmune disorder that primarily affects the joints. Vitamin D has a role in the activity and pathogenesis of RA. The aim of this study is to determine the correlation of vitamin D and anti-cyclic citrullinated peptide (anti-CCP) with disease activity in RA patients. Methods: A case-control study was conducted between November 2021 and February 2022. A questionnaire was designed to obtain demographic and clinical data from both males and females over 18 years old who did not take vitamin D supplements. A total of 142 blood samples were collected in sterile containers from RA patients. Serum vitamin D and anti-CCP levels from cases and control samples were measured using ELISA. Results: Of the cases, 77.45% were females and 22.55% were males, whereas 67.5% of the controls were females and 32.5% were males. The average age of the cases and controls was 48.1 +/- 1.06 years and 34.0 +/- 1.04 years, respectively. The level of vitamin D was 32.5 +/- 1.8 in the cases and 19.1 +/- 1.6 in the controls. The level of anti-CCP was 42.1 +/- 1.6 in the cases and 0.52 +/- 1.4 in the controls. Vitamin D deficiency level ratio was 21.7% for the cases and 61% for controls, vitamin D insufficiency ratio was 30.4% for the cases and 18% for controls, and vitamin D sufficiency ratio was 47.9% for the cases and 21% for controls. Conclusions: There was an inverse negative correlation between vitamin D level and disease activity in RA patients.