FRI672 Bone Mineral Density In Neurofibromatosis Type 1: A Systematic Review And Meta-analysis

Disclosure: N. Charoenngam: None. P. Wattanachayakul: None. A. Jaroenlapnopparat: None. P. Ungprasert: None. J. Chenbhanich: None. Neurofibromatosis type 1 (NF1) is known to be associated with low bone mineral density (BMD) and fragility fractures. However, evidence supporting specific age of early BMD measurement is limited as data on the degree of bone loss in NF1 are lacking. Using systematic review and meta-analysis technique, we aimed to identify all available data to assess BMD in patients with NF1. Potentially eligible studies were identified from Medline and EMBASE databases from inception to February 2023 using search strategy that comprised of terms for “Bone mineral density” and "Neurofibromatosis type 1”. Eligible study must include adult or pediatric patients with NF1. The study must report mean Z-score with variance of total body, lumbar spine, femoral neck or total hip BMD of the studied patients. Point estimates with standard errors were retrieved from each study and were combined using the generic inverse variance method. A total of 1,165 articles were identified. After systematic review, 19 studies were included. The majority of participants in the included studies were children and younger adults with the mean age of participants lower than 50 years old in all but one study. The meta-analysis revealed that patients with NF1 had negative mean Z-scores for total body BMD (pooled mean Z-score -0.808; 95%CI, -1.025 - -0.591) and BMD at lumbar spine (pooled mean Z-score -1.104; 95%CI, -1.376 - -0.833), femoral neck (pooled mean Z-score -0.726; 95%CI, -0.893 - -0.560) and total hip (pooled mean Z-score -1.126; 95%CI, -2.078 - -0.173). The subgroup meta-analysis in pediatric patients aged <18 years revealed that patients with NF1 had negative mean Z-scores for lumbar spine BMD (pooled mean Z-score -0.938; 95%CI, -1.299 - -0.577) and femoral neck BMD (pooled mean Z-score -0.585; 95%CI, -0.872 - -0.298). Based on the results from the meta-analysis, patients with NF1 had low Z-scores. However, the lower limits of the 95% CIs for the pooled mean Z-score for total body and specific site BMD were all higher than the Z-score cut-off of -2 for “low BMD for chronological age” in children and adults aged <50 years old. Therefore, the degree of low BMD may not be of clinical significance. Our results do not support the role of early BMD screening in children and young adults with NF1. Presentation: Friday, June 16, 2023