Wasserman Halley M, Hornung Lindsey N, Stenger Peggy J, Rutter Meilan M, Wong Brenda L, Rybalsky Irina, Khoury Jane C, Kalkwarf Heidi J
Cincinnati Children's Hospital Medical Center, Division of Endocrinology, 3333 Burnet Ave, MLC 7012, Cincinnati, OH 45229, USA.
Cincinnati Children's Hospital Medical Center, Division of Biostatistics and Epidemiology, 3333 Burnet Ave, MLC 5041, Cincinnati, OH 45229, USA.
Neuromuscul Disord. 2017 Apr;27(4):331-337. doi: 10.1016/j.nmd.2017.01.019. Epub 2017 Feb 1.
Patients with Spinal Muscular Atrophy (SMA) are at risk for poor bone health. The prevalence of fractures, low areal bone mineral density (aBMD; Z-score ≤-2.0) of the lateral distal femur and of osteoporosis by SMA subtype is not known. We aimed to describe the natural history of bone health in patients with SMA prior to bisphosphonate treatment. We reviewed data from 85 eligible patients with SMA ages 12 months to 18 years, seen at a single institution between January 2005 and July 2016. Fracture history was reported at annual clinic visits. aBMD was obtained from dual energy x-ray absorptiometry scans of the lumbar spine, total body, and lateral distal femur. 85% of patients had aBMD Z-scores ≤-2.0 SD and were progressively lower with worsening SMA severity. Longitudinal aBMD Z-scores of the lateral distal femur decreased with age. Fractures occurred in 38% (32/85) of patients with the femur being the most common location (25 of 57 fractures). Thirteen percent of patients fulfilled criteria for osteoporosis. Low aBMD and femur fractures are highly prevalent in all SMA subtypes from a young age; however, few patients met the criteria for osteoporosis. Poor bone health may be an under-recognized comorbidity of SMA.
脊髓性肌萎缩症（SMA）患者存在骨骼健康状况不佳的风险。目前尚不清楚SMA各亚型患者中骨折、股骨远端外侧区域骨密度（aBMD；Z评分≤ -2.0）降低以及骨质疏松症的患病率。我们旨在描述双膦酸盐治疗前SMA患者骨骼健康的自然病程。我们回顾了2005年1月至2016年7月期间在单一机构就诊的85例年龄在12个月至18岁之间的符合条件的SMA患者的数据。每年在门诊就诊时报告骨折病史。通过双能X线吸收法扫描获取腰椎、全身和股骨远端外侧的aBMD。85%的患者aBMD Z评分≤ -2.0标准差，且随着SMA严重程度的加重而逐渐降低。股骨远端外侧的纵向aBMD Z评分随年龄下降。38%（32/85）的患者发生骨折，其中股骨是最常见的骨折部位（57例骨折中有25例发生在股骨）。13%的患者符合骨质疏松症标准。低aBMD和股骨骨折在所有SMA亚型中从年轻时起就非常普遍；然而，很少有患者符合骨质疏松症标准。骨骼健康不佳可能是SMA一种未得到充分认识的合并症。
