Summary

Hypophosphatasia (HPP) is a rare disease affecting bone mineralization. Adults with HPP have an increased occurrence of low-energy fractures, which cannot be explained by reduced bone mass assessed by dual energy X-ray absorptiometry. The bone phenotype in adults with HPP requires further studies investigating bone strength and bone structural parameters.

Introduction

Hypophosphatasia (HPP) is a rare inherited disorder of bone and mineral metabolism, characterized by broad-ranging clinical manifestations and severity. However, studies investigating the clinical spectrum in adults with HPP compared to a control group are scarce. The aim of this study was to evaluate biochemical and clinical characteristics as well as bone health in a Danish cohort of adults with HPP.

Methods

We conducted a cross-sectional study assessing biochemical parameters, fracture prevalence, bone mineral density (BMD), bone turnover markers, physical performance and pain characteristics in 40 adults with HPP and 40 sex-, age-, BMI- and menopausal status-matched healthy controls.

Results

Patients with HPP had a significantly higher prevalence of non-vertebral, low-energy fractures (p = < 0.001). BMD at the lumbar spine, total hip, femoral neck, forearm and whole body did not differ between the groups. Low levels of the bone-specific alkaline phosphatase correlated significantly with higher BMD at the lumbar spine and femoral neck in both groups. The bone formation marker N-terminal propeptide of type 1 procollagen was significantly lower in patients with HPP than healthy controls (p = 0.006). Adults with HPP had significantly reduced walking capability (p = < 0.001) and lower body strength (p = < 0.001). Chronic pain was significantly more prevalent in adults with HPP than the control group (p = 0.029).

Conclusions

The increased occurrence of low-energy fractures in adults with HPP is not explained by low BMD. Adults with HPP have reduced physical performance when compared with healthy controls.

中文翻译：

---

成人低磷酸酯酶症的生化和临床表现：一项全国性横断面研究

概括

低磷酸酯酶症（HPP）是一种影响骨矿化的罕见疾病。患有 HPP 的成年人低能量骨折的发生率增加，这不能用双能量 X 射线骨密度仪评估的骨量减少来解释。HPP 成人的骨表型需要进一步研究，调查骨强度和骨结构参数。

介绍

低磷酸酯酶症（HPP）是一种罕见的遗传性骨和矿物质代谢疾病，具有广泛的临床表现和严重程度。然而，与对照组相比，研究HPP成人临床谱的研究很少。本研究的目的是评估丹麦 HPP 成人队列的生化和临床特征以及骨骼健康。

方法

我们进行了一项横断面研究，评估了 40 名 HPP 成人和 40 名性别、年龄、BMI 和绝经状态匹配的成人的生化参数、骨折患病率、骨矿物质密度 (BMD)、骨转换标志物、身体表现和疼痛特征健康的对照。

结果

HPP 患者的非椎体低能量骨折发生率显着升高（p  = < 0.001）。腰椎、全髋、股骨颈、前臂和全身的 BMD 在各组之间没有差异。在两组中，低水平的骨特异性碱性磷酸酶与较高的腰椎和股骨颈 BMD 显着相关。与健康对照组相比，HPP 患者的 1 型前胶原的骨形成标志物 N 末端前肽显着降低 ( p  = 0.006)。患有 HPP 的成年人的行走能力（p  = < 0.001）和下肢力量显着降低（p  = < 0.001）。慢性疼痛在患有 HPP 的成年人中比对照组更普遍（p = 0.029)。

结论

低 BMD 不能解释 HPP 成人低能量骨折发生率的增加。与健康对照组相比，患有 HPP 的成年人的体能下降。