Sleep Disorders Center, Department of Medicine and Surgery, University of Parma, Parma, Italy.
Neurology Service, Multidisciplinary Sleep Unit, Universitat de Barcelona, IDIBAPS, CIBERNED, Hospital Clinic de Barcelona, Barcelona, Spain.
Sleep. 2019 Oct 9;42(10). doi: 10.1093/sleep/zsz142.
To evaluate the role of sleep cyclic alternating pattern (CAP) in patients with isolated REM sleep behavior disorder (IRBD) and ascertain whether CAP metrics might represent a marker of phenoconversion to a defined neurodegenerative condition.
Sixty-seven IRBD patients were included and classified into patients who phenoconverted to a neurodegenerative disease (RBD converters: converter REM sleep behavior disorder [cRBD]; n = 34) and remained disease-free (RBD non-converters: non-converter REM sleep behavior disorder [ncRBD]; n = 33) having a similar follow-up duration. Fourteen age- and gender-balanced healthy controls were included for comparisons.
Compared to controls, CAP rate and CAP index were significantly decreased in IRBD mainly due to a decrease of A1 phase subtypes (A1 index) despite an increase in duration of both CAP A and B phases. The cRBD group had significantly lower values of CAP rate and CAP index when compared with the ncRBD group and controls. A1 index was significantly reduced in both ncRBD and cRBD groups compared to controls. When compared to the ncRBD group, A3 index was significantly decreased in the cRBD group. The Kaplan-Meier curve applied to cRBD estimated that a value of CAP rate below 32.9% was related to an average risk of conversion of 9.2 years after baseline polysomnography.
IRBD is not exclusively a rapid eye movement (REM) sleep parasomnia, as non-rapid eye movement (non-REM) sleep microstructure can also be affected by CAP changes. Further studies are necessary to confirm that a reduction of specific CAP metrics is a marker of neurodegeneration in IRBD.
评估孤立性快速眼动睡眠行为障碍（IRBD）患者睡眠周期性交替模式（CAP）的作用，并确定 CAP 指标是否可以作为向明确神经退行性疾病表型转化的标志物。
纳入 67 例 IRBD 患者，并根据是否向神经退行性疾病表型转化进行分类（RBD 转化：转化 REM 睡眠行为障碍 [cRBD]；n=34）和保持无疾病状态（RBD 未转化：未转化 REM 睡眠行为障碍 [ncRBD]；n=33），随访时间相似。纳入 14 名年龄和性别匹配的健康对照者进行比较。
与对照组相比，IRBD 患者的 CAP 率和 CAP 指数显著降低，主要是由于 A1 期亚型（A1 指数）减少，尽管 CAP A 和 B 期的持续时间均增加。与 ncRBD 组和对照组相比，cRBD 组的 CAP 率和 CAP 指数明显较低。与对照组相比，ncRBD 和 cRBD 组的 A1 指数均显著降低。与 ncRBD 组相比，cRBD 组的 A3 指数显著降低。Kaplan-Meier 曲线应用于 cRBD 估计，CAP 率值低于 32.9%与基线多导睡眠图后平均 9.2 年的转化风险相关。
IRBD 不仅仅是快速眼动（REM）睡眠行为障碍，非快速眼动（非 REM）睡眠微结构也可受到 CAP 变化的影响。需要进一步研究以确认特定 CAP 指标的减少是 IRBD 神经退行性变的标志物。
