Regularly sleeping six hours or fewer per night during middle age is associated with a greater risk of dementia, according to a new study of nearly 8,000 British adults followed over 25 years, published this week in Nature Communications. These findings cannot establish cause and effect, but suggest a link exists between sleep duration and dementia risk.

本周发表在《自然通讯》杂志上的一项对近8000名英国成年人进行了长达25年的跟踪调查的新研究表明，中年人每晚规律睡眠6小时或更少与患痴呆症的风险更高有关。这些发现虽然不能确定两者的因果关系，但已经表明了睡眠时间和痴呆风险之间存在联系。

Nearly 10,000,000 new cases of dementia are reported worldwide every year. A common symptom is altered sleep; however, there is growing evidence to suggest sleep patterns before dementia onset may contribute to the disease. Time spent sleeping is linked to dementia risk in older adults (65 years and older), but it is unclear whether this association is also true for younger age groups.

全世界每年有近10,000,000个新的痴呆症病例被报道。一个常见的症状是睡眠改变; 然而，越来越多的证据表明，痴呆症发病前的睡眠模式可能会导致这种疾病。睡眠时间与老年人(65岁及以上)患痴呆症的风险有关，但尚不清楚这种关联是否也适用于年轻人群。

Séverine Sabia and colleagues analysed survey data from UCL’s Whitehall II study that has examined the health of 7,959 British individuals since 1985. Participants self-reported their sleep duration, and some wore watch accelerometers overnight to confirm this was an accurate estimate. The study shows higher risk of dementia in those sleeping six or fewer hours per night at the age of 50 or 60. There was also a 30% increased dementia risk in those with consistently short sleeping patterns from middle to older age (from 50 to 70 years), irrespective of cardiometabolic or mental health issues (known risk factors for dementia).

萨比亚和他的同事分析了加州大学白厅二期研究的调查数据，该研究自1985年以来对7959名英国人的健康状况进行了调查。参与者自我报告他们的睡眠时间，一些人睡觉时佩戴计数手表以确保数据的准确性。研究显示，抛开心脏代谢或精神健康问题(痴呆的已知危险因素)，在50岁或60岁的人中，每晚睡6小时或更少的人患痴呆的风险更高，在中老年睡眠不足的人群(50至70岁)中，痴呆风险也增加了30%。

The findings suggest sleep may be important for brain health in midlife. Future research may be able to establish whether improving sleep habits may help prevent dementia.

研究结果表明，睡眠对中年大脑健康可能很重要。未来的研究也许能够确定改善睡眠习惯是否有助于预防痴呆症。