The aim of this study was to analyze the relationship between the initiation of CPAP therapy and HRV in patients with OSA. The study group consisted of 37 patients, aged 34–79 (mean 54.95 years) with OSA treated with CPAP. Two subgroups of patients were distinguished: less than severe (AHI < 30, n = 16) and severe OSA (AHI ≥ 30, n = 21). The second study was carried out around a month after the initiation of therapy. CPAP therapy caused the improvement in polysomnographic parameters, however, in most parameters in time and frequency analysis, there were no significant positive changes in parasympathetic tone. Moreover, in HRV time analysis, the reduced rMSSD and pNN50 parameters in the hours of night rest and rMSSD and SDSD during the 15-min N3 sleep period were noted. Especially, in the group with AHI ≥ 30, we observed significant decreases in rMSSD and pNN50 for the entire time. The changes were mainly for the night periods including the N3 sleep period, which is especially connected with sleep apnea (parameters: rMSSD, SDSD, and pNN50). In spectral analysis, the decrease in HF from the 15-min daily activity period and the N3 sleep period was observed. Inverse correlations were seen between the maximum, median, and mean positive airway pressure (PAP) and the change in rMSSD, SDNN, and SDSD, mainly during night hours and the N3 sleep period. Only in patients with AHI < 30 the increase in SDNN was observed in 15-min N3 sleep period. The beneficial increase in SDNN parameter from time analysis was observed only in one sleep period in less ill patients with OSA. The lack of significant changes was observed in the majority of the parameters of heart rate variability after initiation of CPAP therapy in a short observational time; however, the shift towards reduced HRV was observed in patients with AHI > 30, so the response to CPAP therapy may depends on the severity of the apnea. The results may suggest that a longer observational period is needed in such studies, and the problem is still not fully elucidated.

本研究的目的是分析 OSA 患者开始 CPAP 治疗与 HRV 之间的关系。研究组由 37 名接受 CPAP 治疗的 OSA 患者组成，年龄为 34-79 岁（平均 54.95 岁）。患者分为两个亚组：轻度 OSA（AHI < 30， n = 16）和重度 OSA（AHI ≥ 30， n = 21）。第二项研究是在治疗开始后一个月左右进行的。 CPAP治疗引起多导睡眠图参数的改善，然而，在时间和频率分析的大多数参数中，副交感神经张力没有显着的积极变化。此外，在 HRV 时间分析中，注意到夜间休息时间的 rMSSD 和 pNN50 参数以及 15 分钟 N3 睡眠期间 rMSSD 和 SDSD 的降低。特别是，在 AHI ≥ 30 的组中，我们观察到 rMSSD 和 pNN50 始终显着下降。变化主要发生在夜间时段，包括 N3 睡眠时段，该时段与睡眠呼吸暂停尤其相关（参数：rMSSD、SDSD 和 pNN50）。在频谱分析中，观察到 15 分钟日常活动期和 N3 睡眠期的 HF 减少。最大、中值和平均气道正压 (PAP) 与 rMSSD、SDNN 和 SDSD 的变化之间存在负相关，主要是在夜间和 N3 睡眠期间。仅在 AHI < 30 的患者中，在 15 分钟 N3 睡眠期间观察到 SDNN 增加。仅在病情较轻的 OSA 患者的一个睡眠周期中观察到了时间分析带来的 SDNN 参数的有益增加。 在开始 CPAP 治疗后，在短时间内观察到大多数心率变异性参数没有显着变化；然而，在 AHI > 30 的患者中观察到 HRV 降低的转变，因此对 CPAP 治疗的反应可能取决于呼吸暂停的严重程度。结果可能表明此类研究需要更长的观察期，而且问题仍未完全阐明。