Measurement of Bone Mineral Density by Dual Energy X-ray Absorptiometry in Juvenile Idiopathic Arthritis

To evaluate bone mineral density using dual X-ray absorptiometry in Juvenile Idiopathic Arthritis (JIA) patients and factors affecting it, if any. A cross sectional study was conducted by enrolling thirty five patients of JIA and age and sex matched controls. Bone Mineral Density (BMD) and Z score of whole body, total body less head, lumbar spine and distal radius were obtained and adjusted for age, sex, weight and BMI in both cases and controls. Dietary intake of calcium, vitamin D intake, sunlight exposure, weight bearing physical activity, age of onset, duration of disease, disease activity score and treatment received (prednisolone and methotrexate) were recorded. BMD was significantly lower among patients as compared to controls. Decreased dietary intake of vitamin D and calcium, decreased weight bearing physical activity and sunlight exposure were the major factors for low BMD. Use of steroid also decreased BMD to some extent, whereas use of methotrexate, disease duration and severity did not have a significant correlation with BMD. Apart from disease control, it is important to improve the dietary intake of calcium, vitamin D and encourage more physical activities and exposure to sunlight in JIA patients.