The Relationship between Bone Mineral Density and Dietary Intake in Moroccan Children with Juvenile Idiopathic Arthritis

Background and objective: The aim of this study was to evaluate the association between dietary intake and bone mineral density in children with juvenile idiopathic arthritis (JIA). Methods: A cross-sectional study carried out in Morocco between May 2010 and June 2011, covering out patients with JIA. The characteristics of patients were collected. The nutritional status was assessed by a food questionnaire including data of food intake during 7 consecutive days using 24-hour dietary recall. Food intake was quantified using the software Bilnut (Bilnut version 2.01, 1991). Bone mineral density (BMD in g/cm2) was measured by DXA method (X-ray absorptiometry) on a Lunar Prodigy. Results: The study consisted of 33 patients with JIA (4 - 16 years old). The median age of patients was 10.4 ± 4.3 years. Median disease duration was 2 (1 - 4.5) years. The group of patients with low dietary intake of proteins was associated with low BMD (p = 0.03). Low BMD was related with low intake of magnesium (p = 0.007) and vitamin C (p = 0.04) in children aged between 4 and 9 years. Low intake of vitamin E and folate was associated with high BMD in the other range of children (p < 0.001). Conclusion: This study suggests that low intake of protein and of some micronutrients (magnesium, vitamin C, vitamin E and folate) influence bone mass in children with JIA. Prospective studies with a larger number of patients seem to be necessary in order to confirm our findings.