随着年龄增长，人们的深睡眠时间会越来越短。然而，新研究发现，如果深睡眠时间大幅减少，患痴呆症的风险将会大增。

Loss of slow-wave sleep as you age may increase your risk of developing dementia, according to a new study.

新研究发现，随着年龄增长，慢波睡眠时间的减少可能会增加患痴呆症的风险。

"We found that aging was associated with a decline in the amount of the deepest stages of sleep, known as slow wave sleep,” said Matthew P. Pase, senior author of the study published Monday in the journal JAMA Neurology, via email. Pase is an associate professor of psychology and neurology at Monash University in Australia.

该研究的资深作者、澳大利亚莫纳什大学心理学与神经学副教授马修·P·帕赛在电子邮件中说：“我们发现，随着年龄增长，深睡眠（也就是所谓的慢波睡眠）时间会逐渐减少。”该研究10月30日发表在期刊《美国医学会杂志—神经病学》上。

"We then found that persons with greater declines in slow wave sleep over time had a higher risk of getting dementia over the next 17 years of follow-up,” said Pase via email.

帕赛在电邮中说：“我们还发现，慢波睡眠时间随年龄增长减少幅度更大的人群，未来17年患痴呆症的风险更高。”

Slow-wave sleep is the third stage of sleep, which is important for brain health. During this stage, the body removes unwanted, or potentially harmful, materials from the brain — including beta-amyloid protein, a hallmark sign of Alzheimer’s disease.

慢波睡眠是睡眠的第三个阶段，对大脑健康非常重要。在这一阶段的睡眠中，人体会从大脑中移除不想要的或可能有害的物质，包括β-淀粉样蛋白，这种物质是阿尔茨海默病的一个标志性特征。

For the brain, this deep sleep is thought to be the most restorative, said Dr. Richard Isaacson, director of research at the Institute for Neurodegenerative Diseases in Florida, via email. Isaacson wasn’t involved in the study.

美国佛罗里达州神经退行性疾病研究所的研究部主任理查德·艾萨克森博士在电邮中表示，深睡眠阶段是最有助于大脑恢复的。艾萨克森未参与此项研究。

The authors wanted to know whether chronic reductions in slow-wave sleep over time are linked with dementia risk in humans and vice versa — whether dementia-related processes in the brain may contribute to getting less of this type of sleep.

研究作者们想知道，慢波睡眠时间的长期减少长远来看是否会增加人们患痴呆症的风险，反之，大脑中与痴呆症相关的进行性退化是否会导致慢波睡眠时间减少。

"Results suggest that chronic declines in slow wave sleep, rather than individual differences at any given time, are important for predicting dementia risk.” Pase said.

帕赛表示：“研究表明，相比在任何特定时间的个体差异，慢波睡眠时间长期减少对于预测痴呆风险很重要。”

The researchers studied 346 people who were age 69 on average and had participated in the Framingham Heart Study and completed two overnight sleep studies — one between 1995 to 1998 and the second between 1998 to 2001 — during which their sleep was monitored. Launched by the US National Heart, Lung and Blood Institute in 1948, the Framingham Heart Study identifies common factors contributing to cardiovascular disease.

研究人员调查了参与过弗雷明汉心脏研究的平均年龄69岁的346个人，分别在1995年至1998年间以及1998年至2001年间完成了两项夜间睡眠研究，在这期间对他们的睡眠进行了监测。美国国家心肺和血液研究所1948年发起的弗雷明汉心脏研究查明了导致心血管疾病的常见因素。

The authors also investigated whether any changes in the amount of slow-wave sleep that participants got was associated with developing dementia up to 17 years after they completed the sleep studies.

研究作者还调查了参与者慢波睡眠时间的任何变化是否与完成睡眠研究17年后患痴呆症有关。

By that time, 52 participants had been diagnosed with dementia. Each percentage decrease in slow-wave sleep per year was linked with a 27% increased risk of developing dementia and a 32% higher risk of Alzheimer’s disease dementia. The rate of slow-wave sleep loss accelerated from age 60, peaked from ages 75 to 80 and slowed afterward.

研究结束17年内，已有52名参与者确诊了痴呆症。慢波睡眠时间每年每减少1%，患痴呆症的风险就增加27%，患阿尔茨海默病的风险就增加32%。慢波睡眠时间减少速度从60岁起加快，在75岁至80岁期间达到顶峰，之后又逐渐变慢。

Those who experienced declines in this deep sleep were more likely to have cardiovascular disease, take medications that affect sleep and carry a gene that makes people more at risk for Alzheimer’s (the APOE ε4 allele).

深睡眠减少的人群更可能患上心血管疾病，以及服用影响睡眠的药物，携带阿尔茨海默病高风险基因APOE ε4 allele的人也更可能出现深睡眠减少。

"This is an important study yet again showing the impact of quality of sleep on a person’s risk of cognitive decline and dementia,” Isaacson said. “It’s important to not only pay attention to the total amount a person is sleeping each night, but also monitor sleep quality as best as possible.”

艾萨克森表示：“这项重要研究再次表明了睡眠质量对于一个人患上认知衰退和痴呆症风险的影响。我们不光要注意一个人每夜睡眠的总时长，也要尽可能监测睡眠质量。”

英文来源：美国有线电视新闻网

翻译&编辑：丹妮