Suzuki M, Guilleminault C, Otsuka K, Shiomi T
Stanford University Sleep Disorders Center, California, USA.
Sleep. 1996 Jun;19(5):382-7. doi: 10.1093/sleep/19.5.382.
Obstructive sleep apnea syndrome (OSAS) has been associated with a higher than normal cardiovascular morbidity and mortality. Some OSAS patients lack the sleep-related, nocturnal decrease, or "dip," in blood pressure which is seen in normal individuals. These subjects, called "non-dippers," may be at greater risk for cardiovascular problems. We studied 40 OSAS patients (including 3 women) and 6 control subjects, all identified by polysomnography, for nocturnal blood pressure "dipping." We performed a second nocturnal polysomnogram to determine their apnea and hypopnea indices, (A + H)I, and oxygen saturation levels at the beginning of the study and then initiated 48 hours of ambulatory blood pressure monitoring, with data points collected every 30 minutes. Controls, which included one hypertensive subject, were all dippers. Nineteen OSAS subjects (48% of OSAS individuals) were systolic non-dippers and only 9 of them (22.5%) were diastolic non-dippers. We considered the following clinical variables as potential predictors of non-dipping: age, body mass index, respiratory disturbance index, years of reported loud snoring by bed partners, lowest oxygen saturation during nocturnal sleep, and percentage of sleep time spent with oxygen saturation below 90%. Multiple regression analyses indicated respiratory disturbance index as the only significant variable for systolic (p = 0.04) and diastolic (p = 0.03) blood pressure non-dipping. When we forced the following two nonsignificant variables into the model, they showed a very meager impact: number of years with reported loud snoring (p = 0.4 and p = 0.5, respectively for systolic and diastolic blood pressure non-dipping) and age (p = 0.5 and p = 0.6). The calculated model explained only a low percentage of the variance with an r2 of 0.25 and 0.26 for systolic and diastolic blood pressure non-dipping, respectively. Analysis of hypertension/normotension and dipping/non-dipping failed to show a significant relationship in the studied population. Fifty percent of the normotensive OSAS subjects were non-dippers and 43% of the hypertensive OSAS subjects were also non-dippers. We found a relationship between increasing respiratory disturbance index and increasing average 24-hour systolic blood pressure only when OSAS subjects were non-dippers and hypertensive.
阻塞性睡眠呼吸暂停综合征（OSAS）与高于正常水平的心血管发病率和死亡率相关。一些OSAS患者缺乏正常个体中出现的与睡眠相关的夜间血压下降或“低谷”。这些被称为“非勺型血压者”的受试者可能面临更大的心血管问题风险。我们研究了40例OSAS患者（包括3名女性）和6名对照受试者，所有受试者均通过多导睡眠图确定是否存在夜间血压“勺型变化”。在研究开始时，我们进行了第二次夜间多导睡眠图检查，以确定他们的呼吸暂停和低通气指数（A + H）I以及血氧饱和度水平，然后启动了48小时的动态血压监测，每30分钟收集一次数据点。对照受试者（包括一名高血压患者）均为勺型血压者。19例OSAS受试者（占OSAS个体的48%）为收缩期非勺型血压者，其中只有9例（22.5%）为舒张期非勺型血压者。我们将以下临床变量视为非勺型血压的潜在预测因素：年龄、体重指数、呼吸紊乱指数、床伴报告的大声打鼾年限、夜间睡眠期间的最低血氧饱和度以及血氧饱和度低于90%的睡眠时间百分比。多元回归分析表明，呼吸紊乱指数是收缩压（p = 0.04）和舒张压（p = 0.03）非勺型变化的唯一显著变量。当我们将以下两个不显著的变量纳入模型时，它们显示出非常微弱的影响：报告的大声打鼾年限（收缩压和舒张压非勺型变化分别为p = 0.4和p = 0.5）以及年龄（p = 0.5和p = 0.6）。计算出的模型仅解释了较低比例的方差，收缩压和舒张压非勺型变化的r2分别为0.25和0.26。对高血压/血压正常和勺型/非勺型的分析未能在研究人群中显示出显著关系。50%的血压正常的OSAS受试者为非勺型血压者，43%的高血压OSAS受试者也是非勺型血压者。我们发现，仅当OSAS受试者为非勺型血压者且患有高血压时，呼吸紊乱指数增加与2４小时平均收缩压升高之间存在关联。
