Background The idiopathic inflammatory myopathies (IIMs) are a group of rare conditions characterised by muscle inflammation (myositis). Accurate disease activity assessment is vital in both clinical and research settings, however, current available methods lack ability to quantify associated variation of physical activity, an important consequence of myositis.This study aims to review studies that have collected accelerometer-derived physical activity data in IIM populations, and to investigate if these studies identified associations between physical and myositis disease activity. Methods A narrative review was conducted to identify original articles that have collected accelerometer-derived physical activity data in IIM populations. The following databases were searched from February 2000 until February 2019: Medline via PubMed, Embase via OVID and Scopus. Results Of the 297 publications screened, eight studies describing accelerometer use in 181 IIM cases were identified. Seven out of the eight studies investigated juvenile dermatomyositis (JDM) populations and only one reported on an adult-onset population. Population sizes, disease duration, accelerometer devices used, body placement sites, and study duration varied between each study.Accelerometer-derived physical activity levels were reduced in IIM cohorts, compared to healthy controls, and studies reported improvement of physical activity levels following exercise programme interventions, thus demonstrating efficacy.Higher levels of accelerometer-derived physical activity measurements were associated with shorter JDM disease duration, current glucocorticoid use and lower serum creatine kinase. However, no clear association between muscle strength and accelerometer-derived physical activity measures was identified. Conclusions The use of accelerometer-derived physical activity in IIM research is in its infancy. Whilst knowledge is currently limited to small studies, the opportunities are promising and future research in this area has the potential to improve disease activity assessment for clinical and research applications.

中文翻译：

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特发性炎症性肌病中加速度计衍生的身体活动的回顾。

背景 特发性炎症性肌病 (IIM) 是一组以肌肉炎症 (肌炎) 为特征的罕见疾病。准确的疾病活动评估在临床和研究环境中都至关重要，然而，目前可用的方法缺乏量化身体活动相关变化的能力，这是肌炎的一个重要后果。本研究旨在回顾收集加速度计衍生的身体活动数据的研究IIM 人群，并调查这些研究是否确定了身体和肌炎疾病活动之间的关联。方法 进行叙述性审查，以确定在 IIM 人群中收集了加速度计衍生的身体活动数据的原始文章。从 2000 年 2 月到 2019 年 2 月，搜索了以下数据库：Medline via PubMed，Embase 通过 OVID 和 Scopus。结果 在筛选的 297 篇出版物中，确定了 8 项描述加速度计在 181 例 IIM 病例中的使用的研究。八项研究中有七项调查了青少年皮肌炎 (JDM) 人群，只有一项报告了成人发病人群。人口规模、疾病持续时间、使用的加速度计设备、身体放置部位和研究持续时间因每项研究而异。与健康对照组相比，IIM 队列中加速度计衍生的身体活动水平降低，研究报告锻炼计划后身体活动水平有所改善更高水平的加速度计衍生的身体活动测量与更短的 JDM 疾病持续时间、当前糖皮质激素的使用和更低的血清肌酸激酶相关。然而，肌肉力量和加速度计衍生的身体活动测量之间没有明确的关联。结论 在 IIM 研究中使用加速度计衍生的身体活动尚处于起步阶段。虽然目前知识仅限于小型研究，但机会是有希望的，该领域的未来研究有可能改善临床和研究应用的疾病活动评估。