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Bone health in juvenile idiopathic arthritis compared with controls based on a Norwegian observational study
Anette Lundestad1,2, Lena Cetrelli3,4, Oskar Welander Angenete5,6
1Department of Clinical and Molecular Medicine (IKOM), Norwegian University of Science and Technology, Trondheim, Norway anette.lundestad@ntnu.no.
Insights
Children with juvenile idiopathic arthritis (JIA) have bone mineral density (BMD) similar to controls. Higher physical activity levels in children with JIA are linked to better BMD, highlighting the importance of exercise for bone health.
Area of Science:
- Pediatric Rheumatology
- Bone Metabolism
- Arthritis Research
Background:
- Juvenile idiopathic arthritis (JIA) poses a risk to bone health in children.
- This study investigates bone mineral density (BMD) and associated risk factors in pediatric patients.
Purpose of the Study:
- To evaluate bone mineral density (BMD) in children with JIA.
- To identify risk factors contributing to reduced BMD in this population.
Main Methods:
- The NorJIA study involved Norwegian children with JIA and matched controls.
- Dual-energy X-ray absorptiometry (DXA) was used to measure BMD, adjusted for bone age.
- Clinical data, questionnaires, imaging, and blood tests were collected.
Main Results:
- No significant differences in BMD Z-scores were observed between children with JIA and controls.
- A strong positive association was found between physical activity levels and BMD in both groups.
- Children with JIA demonstrated similar physical activity levels to controls.
Conclusions:
- BMD in children with JIA is comparable to healthy controls.
- Physical activity is a key factor positively influencing BMD in children with JIA.
- Early disease management, steroid-sparing treatments, and promoting physical activity are crucial for optimizing bone health in JIA.
Background:
Children with juvenile idiopathic arthritis (JIA) are at risk for impaired bone health. This study evaluates bone mineral density (BMD) and potential risk factors for reduced BMD.
Methods:
In the NorJIA study, Norwegian children with JIA, and age-matched and sex-matched controls participated in a multicentre cohort study with clinical examinations, questionnaires, imaging and blood tests. BMD was measured using dual-energy X-ray absorptiometry and adjusted for bone age. Standard descriptive statistics and t-tests were used.
Results:
205 children with JIA had BMD measured at two study visits, 2 years apart and 125 controls at the second visit. At visit 2, median age was 14.7 years (IQR 11.5-16.6). Median disease duration was 6.6 (IQR 4.7-10.4) years, 50.7% had used or were currently using biologic disease-modifying antirheumatic drugs and 25.9% had ever used systemic steroids. There were no substantial differences in BMD Z-scores between the JIA group and controls. Mean BMD Z-score L1-L4 in JIA was 0.0 (95% CI -0.1, 0.1) and in controls 0.1 (95% CI -0.1, 0.3). A robust association was seen between physical activity levels and BMD. In children with JIA, the mean BMD Z-score L1-L4 was -0.3 (95% CI -0.6, 0.0) in the low-activity group and 0.2 (95% CI 0.0, 0.4) in the high-activity group, with a similar trend in controls. Children with JIA were as physically active as controls.
Conclusions:
BMD Z-scores in JIA were similar to controls and positively associated with physical activity. This underlines the importance of early disease control, steroid-sparing medications and physical activity to optimise bone health.
Trial Registration Number:
NCT03904459.
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