Sangha Gina, Yao Bohao, Lunn Daniel, Skorupinska Iwona, Germain Louise, Kozyra Damian, Parton Matt, Miller James, Hanna Michael G, Hilton-Jones David, Freebody Jane, Machado Pedro M
Department of Neurology, Oxford University Hospitals NHS Foundation Trust, Oxford, UK.
Department of Statistics, University of Oxford, Oxford, UK.
J Neurol Neurosurg Psychiatry. 2021 Apr 13. doi: 10.1136/jnnp-2020-325141.
To describe decline in muscle strength and physical function in patients with sporadic inclusion body myositis (IBM).
Manual muscle testing (MMT), quantitative muscle testing (QMT) and disability scoring using the IBM Functional Rating Scale (IBMFRS) were undertaken for 181 patients for up to 7.3 years. The relationship between MMT, QMT and IBMFRS composite scores and time from onset were examined using linear mixed effects models adjusted for gender and age of disease onset. Adaptive LASSO regression analysis was used to identify muscle groups that best predicted the time elapsed from onset. Cox proportional hazards regression was used to evaluate time to use of a mobility aid.
Multilevel modelling of change in percentage MMT, QMT and IBMFRS score over time yielded an average decline of 3.7% (95% CI 3.1% to 4.3%), 3.8% (95% CI 2.7% to 4.9%) and 6.3% (95% CI 5.5% to 7.2%) per year, respectively. The decline, however, was not linear, with steeper decline in the initial years. Older age of onset was associated with a more rapid IBMFRS decline (p=0.007), but did not influence the rate of MMT/QMT decline. Combination of selected muscle groups allowed for generation of single measures of patient progress (MMT and QMT factors). Median (IQR) time to using a mobility aid was 5.4 (3.6-9.2) years, significantly affected by greater age of onset (HR 1.06, 95% CI 1.04 to 1.09, p<0.001).
This prospective observational study represents the largest IBM cohort to date. Measures of patient progress evaluated in this study accurately predict disease progression in a reliable and useful way to be used in trial design.
描述散发性包涵体肌炎（IBM）患者肌肉力量和身体功能的下降情况。
对181例患者进行了长达7.3年的徒手肌力测试（MMT）、定量肌肉测试（QMT）以及使用IBM功能评定量表（IBMFRS）进行残疾评分。使用针对性别和发病年龄进行调整的线性混合效应模型，研究MMT、QMT和IBMFRS综合评分与发病时间之间的关系。采用自适应LASSO回归分析来确定最能预测发病后经过时间的肌肉群。使用Cox比例风险回归来评估使用移动辅助工具的时间。
MMT、QMT和IBMFRS评分随时间变化的多层次模型显示，每年平均下降分别为3.7%（95%可信区间3.1%至4.3%）、3.8%（95%可信区间2.7%至4.9%）和6.3%（95%可信区间5.5%至7.2%）。然而，下降并非呈线性，最初几年下降更为陡峭。发病年龄较大与IBMFRS下降更快相关（p = 0.007），但不影响MMT/QMT下降速度。选定肌肉群的组合可生成患者进展的单一测量指标（MMT和QMT因素）。使用移动辅助工具的中位（四分位间距）时间为5.4（3.6 - 9.2）年，发病年龄较大对其有显著影响（风险比1.06，95%可信区间1.04至1.09，p < 0.001）。
这项前瞻性观察性研究是迄今为止最大的IBM队列研究。本研究中评估的患者进展指标以可靠且有用的方式准确预测疾病进展，可用于试验设计。
