D El Badri, S Rostom, I Bouaddi, A Hassani, B Chkirate, B Amine1 and N Hajjaj-Hassouni
Aim: The aim of this study was to evaluate the bone mineral density (BMD) in Moroccan patients with juvenile idiopathic arthritis and its correlates with disease parameters and vitamin D status.
Methods: Forty patients with juvenile idiopathic arthritis (JIA) were included in a cross-sectional study. The diagnosis of JIA was made according to the criteria of the International League of Association of Rheumatology (ILAR). Information on disease activity, quality of life, sex, age, age at diagnosis, duration of medication use and bone fractures were collected by use of a standardized questionnaire. Patients underwent anthropometric assessment, puberty staging and BMD assessment by dual energy X-ray absorptiometry of the lumbar spine, and total body. Bone mineral density (in g/cm2) was expressed in Z-scores, the number of standard deviation above or below the mean value of an age- and sex-matched reference population. In children, low BMD was defined as a Z-score less than -2 and osteoporosis was defined as a Z-score less than-2 with a fracture history. The daily intake of calcium was determined by the translated version in Moroccan Arabic language of Fardellone questionnaire. Laboratory evaluations included serum calcium, phosphate, alkaline phosphatase, 25-hydroxyvitamin D were assessed.
Results: Forty children with JIA were included (22 male, 18 female); the mean of age of the patients was 11 ± 4.23 years. The median of disease duration was 2 years [1-5]. Eighteen (45%) patients had polyarticular JIA and 60% used corticosteroids. Twenty patients (50%) were given a diagnosis of low BMD and no patient was given a diagnosis of osteoporosis. Bone mineral density Z score in lumbar spine showed a statistically significant correlation with cumulative dose of corticosteroids (β=-0.40, p=0.05) and systemic subtype of JIA (β=-1.07, p=0.01) and the BMD in total body showed a statistically significant correlation with weight (β=0.40, p=0.009) and height (β=0.37, p=0.01). However, there was no significant association in our study between the BMD and disease duration, daily intake of calcium, and 25-hydroxyvitamin D.
Conclusion: This study suggests that osteopenia was a frequent complication