Department of Clinical Neurophysiology, Seinäjoki Central Hospital, Hanneksenrinne 6, 60220 Seinäjoki, Finland.
Med Biol Eng Comput. 2013 Jun;51(6):697-708. doi: 10.1007/s11517-013-1039-4. Epub 2013 Feb 16.
Sleep apnea-hypopnea syndrome (SAHS) causes impairment of daytime functions and increases risk of cardiovascular diseases. Apnea-hypopnea index (AHI), currently used for the estimation of the severity of SAHS, does not contain information on the morphology or duration aspects of the breathing cessations and related oxygen desaturations. Longer breathing cessations and deeper desaturations may have more severe consequences than shorter and shallower ones. To address these issues, novel parameters containing information on the duration and morphology of breathing cessations and oxygen desaturations were calculated and evaluated on 160 male patients (40 patients in normal, mild, moderate and severe AHI severity categories). Obstruction and desaturation duration parameters consist of sum of event durations normalized with the total analysed time. Desaturation severity is a sum of desaturation event areas normalized with total analysed time and obstruction severity parameter is a sum of the products of apnea and hypopnea durations and related desaturation areas normalized with total analysed time. The median follow-up time of the patients was 183 months (range 154-215 months). The 40 patients in each category were further divided into subgroups A and B with lowest and highest novel parameter values, respectively. AHI showed no differences between the subgroups. Mortality was increased in subgroups B compared to subgroups A. The correlation of the novel parameters with AHI was only moderate and the parameter values were partially overlapping between the AHI severity categories. This suggests that patients with similar AHI may in fact suffer from SAHS of very different severity. Thus, the present results suggest that the novel parameters could bring new insight to the individual estimation of the severity of SAHS.
睡眠呼吸暂停低通气综合征（SAHS）会导致日间功能受损，并增加心血管疾病的风险。目前用于估计 SAHS 严重程度的呼吸暂停低通气指数（AHI），并未包含呼吸暂停和相关氧饱和度下降的形态或持续时间方面的信息。较长的呼吸暂停和更深的氧饱和度下降可能比较短和较浅的呼吸暂停和氧饱和度下降有更严重的后果。为了解决这些问题，我们计算并评估了 160 名男性患者（正常、轻度、中度和重度 AHI 严重程度类别各 40 名患者）的新型参数，这些参数包含呼吸暂停和氧饱和度下降的持续时间和形态方面的信息。阻塞和脱氧持续时间参数由事件持续时间总和除以总分析时间得到。脱氧严重程度是脱氧事件面积总和除以总分析时间，而阻塞严重程度参数是呼吸暂停和低通气持续时间与相关脱氧面积总和除以总分析时间的乘积。患者的中位随访时间为 183 个月（范围 154-215 个月）。每个类别中的 40 名患者进一步分为亚组 A 和 B，其最低和最高新型参数值分别为。亚组 A 和 B 之间的 AHI 没有差异。与亚组 A 相比，亚组 B 的死亡率增加。新型参数与 AHI 的相关性仅为中度，且参数值在 AHI 严重程度类别之间部分重叠。这表明具有相似 AHI 的患者实际上可能患有严重程度非常不同的 SAHS。因此，目前的结果表明，这些新型参数可以为 SAHS 严重程度的个体评估提供新的见解。
