Decoding the Role of Vitamin D Deficiency in Subjects with Osteoarthritis: A Clinico-Observational Study

Abstract

Background: OA most commonly affects the knee joint, knee osteoarthritis being the most common musculoskeletal disease globally reported in nearly 4% of the total world’s population. Previous literature data has established a clear link between vitamin D deficiency and prevalence and increased progression of knee OA. However, few studies deny any such association.

Aims: The present study was conducted to assess the role of Vitamin D deficiency in subjects with Osteoarthritis.

Materials and Methods: The study included 200 subjects of both genders within the age range of 40-65 years with the confirmed clinical and radiographic diagnoses of osteoarthritis. The study subjects were divided into 2 groups of 100 subjects each Group I included 100 subjects newly diagnosed clinically and radiographically for osteoarthritis and Group II had age-matched controls. Under the strict aseptic and sterile conditions, intravenous blood is collected from the antecubital vein for biochemical investigations. The collected blood was allowed to clot and collected clear serum was centrifuged at 3000 rpm for 15 minutes. Vitamin D assay was done using CHEMILUMINESCENT MICROPARTICLE  IMMUNOASSAY (CMIA) method. Calibration Range: 0.0 – 160.0 ng/ml (0.0- 400.0nmol/l) and the reference Range: 15.7 -60.3 ng/ml.

Results: OA Grades are found to be strongly and positively correlated with WOMAC Score (r =0.94, p-value = <0.01) which means with an increase in the WOMAC SCORE, there is an increase in the grades, the severity of the disease. However, Vitamin D level is strongly and negatively correlated with grades of osteoarthritis (r = - 0.272, p-value = 0.006). A significant association of dependent ordinal variable OA Grades with continuous variables i.e., age, Vitamin D level, and WOMAC score was seen. The association is evaluated using ordinal regression. Age and WOMAC Score were positively associated with OA Grades (p-value = 0.005* and <0.001* respectively). However, Vitamin D level is negatively associated with OA Grades (p-value = 0.02*).

Conclusion: The present study concludes that a significant association between osteoarthritis and vitamin D deficiency and also there was a significant association between grades of osteoarthritis and serum Vitamin D levels. Vitamin D level is strongly and negatively correlated with grades of osteoarthritis which implies that with the decrease in the Vitamin D level there is an increase in the grades of disease.