Oasi Research Institute - IRCCS, Italy.
Department of Biomedical and Neuromotor Sciences, University of Bologna, Italy.
Sleep. 2018 Mar 1;41(3). doi: 10.1093/sleep/zsy008.
To define statistically the upper limit of the intermovement interval (IMI, the time interval between the onset of consecutive movements) of periodic leg movements during sleep (PLMS).
We computed the IMI distribution of a large sample (n = 141) of patients with restless legs syndrome (RLS) and analyzed it with two independent approaches, based on fitting either empirical functions or normal and exponential functions to the data.
The two fitting approaches consistently pointed to an upper limit of the PLMS IMI in the range between 50 and 60 s. Decreasing the upper limit of PLMS IMI from 90 to 60 s evidently decreased the PLMS index in patients with RLS and control participants; nevertheless, the PLMS index remained significantly higher in RLS vs. control participants. Shifting the upper limit of PLMS IMI to 60 s did not significantly modify the effectiveness of discrimination of PLMS between controls and patients with RLS.
These results seem to indicate that a conservative, yet data-driven upper limit for IMI contributing to the PLMS in patients with RLS might be 60 s instead of 90 s, as recommended by the present guidelines.
通过统计学方法确定睡眠周期性肢体运动（PLMS）中相邻运动起始之间的时间间隔（IMI）的上限。
我们对一大组（n=141）不宁腿综合征（RLS）患者的 IMI 分布进行了计算，并通过两种独立的方法进行了分析，即根据经验函数或正态和指数函数对数据进行拟合。
两种拟合方法均一致指出，PLMS IMI 的上限在 50 到 60 秒之间。将 PLMS IMI 的上限从 90 秒降低到 60 秒，可明显降低 RLS 患者和对照组参与者的 PLMS 指数；然而，RLS 患者的 PLMS 指数仍然明显高于对照组。将 PLMS IMI 的上限移至 60 秒，并未显著改变 PLMS 在对照组和 RLS 患者之间的区分效果。
这些结果似乎表明，对于 RLS 患者的 PLMS，一个保守的、基于数据驱动的 IMI 上限可能是 60 秒，而不是当前指南建议的 90 秒。
