治疗儿童睡眠呼吸暂停可改善脑功能

波士顿——一项前瞻性研究显示，治疗儿童的阻塞性睡眠呼吸暂停(OSA)可逆转其脑神经元异常。

既往研究显示，OSA与注意力、认知和执行功能缺陷相关。丹佛市科罗拉多大学儿童医院科罗拉多睡眠中心的Halbower博士指出：“本项研究是首次探索OSA治疗对脑神经元损伤的影响，并显示出治疗与儿童注意力和语言记忆改善相关。”

这项研究中共纳入28例年龄为8~11岁的儿童，其中17例患有中度或重度OSA，11例为年龄、性别、种族和社会经济地位相匹配的健康对照。基线时，所有参与者均接受神经心理学测试，其中22例儿童(15例OSA患儿和7例健康对照)也接受了磁共振波谱成像检查。治疗后6个月，11例OSA患儿再次接受脑影像学和神经心理学测试。针对OSA的治疗包括：对于呼吸暂停-低通气指数(AHI)评分＞3的患儿，在增生腺扁桃体切除术后给予连续气道正压(CPAP)监测，对于AHI2~3的患儿进行鼻部治疗。

结果显示，在OSA患儿中，基线时的平均AHI评分为13.6，健康对照的平均AHI评分为0.3，这种差异在脑影像学检查和功能测试中也有所体现。尤其是，“与健康对照相比，OSA患儿左侧海马和左侧额叶皮质中的N-乙酰天冬氨酸/胆碱(NAA/Cho)比值降低，并且OSA患儿的工作记忆、注意力和语言记忆的执行功能显著降低”。治疗后，“右侧和左侧额叶皮质的神经元代谢产物恢复正常，并且海马代谢产物发生中度改善，”Halbower医生说。随访神经心理学测试显示语言记忆和注意力显著改善，“这与额叶的(NAA/Cho)比值恢复正常相关”。

对数据的进一步分析显示，在轻度OSA患儿中，AHI的改善与更全面的海马异常逆转相关，但研究者承认上述结果“还非常初步”。

研究者总结认为，早期诊断和治疗OSA可改善患儿脑功能，尤其是对执行功能、学习和记忆的“中继站”海马的功能改善更为明显。

Halbower医生披露无相关利益冲突。

By: DIANA MAHONEY, Pediatric News Digital Network

BOSTON – Neuronal abnormalities in the brains of children with obstructive sleep apnea are reversible with treatment, a prospective study has shown.

The findings are the first to show that the altered brain metabolites of the frontal cortex – the neuronal network responsible for attention and executive function – normalize with treatment of pediatric obstructive sleep apnea, Dr. Ann C. Halbower reported at the annual meeting of the Associated Professional Sleep Societies.

Previous studies have demonstrated an association between obstructive sleep apnea (OSA) and deficits in attention, cognition, and executive function, "but ours is the first to look at the effect of [OSA] treatment on the neuronal brain injury and to show a relationship between treatment and improvements in attention and verbal memory in these patients," said Dr. Halbower of the Children’s Hospital Colorado Sleep Center and the University of Colorado at Denver.

The study included 28 children aged 8-11 years; 17 had moderate or severe OSA and 11 were healthy controls matched by age, sex, race, and socioeconomic status. At study baseline, all participants underwent neuropsychological testing, and 22 of the children (15 with OSA and 7 healthy controls) also underwent magnetic resonance spectroscopy imaging. Six months post treatment, 11 of the OSA patients underwent repeat brain imaging and neuropsychological testing, Dr. Halbower said. Treatment for OSA consisted of adenotonsillectomy followed by monitored continuous positive airway pressure (CPAP) for children whose apnea-hypopnea index (AHI) score was higher than 3, or nasal treatments for those with an AHI score of 2-3, she explained.

Among the OSA patients, the mean AHI score at baseline was 13.6, compared with 0.3 for the healthy controls – a discrepancy mirrored by differences observed in both the brain imaging and the function tests. Specifically, Dr. Halbower reported, "the N-acetyl aspartate to choline (NAA/Cho) ratios in the left hippocampus and left frontal cortex were significantly decreased in [OSA] patients, compared with healthy controls, and the [OSA] patients had significant decreases in the executive function of working memory, attention, and verbal memory."

After treatment, "the neuronal metabolites of the right and left frontal cortex normalized, and the hippocampal metabolites improved with a medium effect size," Dr. Halbower said. The follow-up neuropsychological testing showed significant improvements in verbal memory and attention, "which correlated with the normalization of the [NAA/Cho] ratios in the frontal lobes," she said. A further analysis of the data linked improvement on the AHI with a more complete reversal of the hippocampal abnormalities in children with mild OSA, she said, noting, however, that this finding "is very preliminary."

Based on the study results, "we speculate that early diagnosis and treatment of obstructive sleep apnea in children could have profound effects on the trajectory of their development," Dr. Halbower said. In particular, she suggested, earlier treatment may lead to a "more brisk improvement" in the hippocampus, which is the "relay station" for executive function, learning, and memory.

Dr. Halbower said she had no relevant financial disclosures.