Some people might not mind spending time alone, but new research with data from 18 countries suggests that older people who struggle with loneliness — rather than strictly being alone — may experience a faster mental and physical decline.

有些人可能不介意独处，但来自18个国家的新研究数据表明，与孤独作斗争的老年人——而不是严格意义上的独处——可能会经历更快的精神和身体衰退。

The study, led by the University of California, Davis, used advanced statistical modeling to chart loneliness and social isolation as older adults move through stages of cognitive impairment and mortality. The results suggest that loneliness plays a much stronger role in cognitive impairment and shorter life spans than social isolation on its own.

这项由加州大学戴维斯分校（University of California, Davis）牵头的研究，利用先进的统计模型，绘制了老年人在经历认知障碍和死亡阶段时的孤独感和社会孤立感。结果表明，孤独在认知障碍和缩短寿命方面的作用比社会孤立本身要大得多。

“Loneliness is a perception,” said Tomiko Yoneda, an assistant professor of psychology at UC Davis and the study’s lead author. “You could be surrounded by a crowd of people and still feel lonely, whereas isolation is just being alone. Some people might be not lonely at all and be completely content in their solitude.”

“孤独是一种感知，”加州大学戴维斯分校心理学助理教授、该研究的主要作者Tomiko Yoneda说。“你可能被一群人包围，但仍然感到孤独，而孤立只是一个人。有些人可能一点也不孤独，在孤独中完全满足。”

The study was published in the Journal of Personality and Social Psychology on June 15.

这项研究发表在6月15日的《个性与社会心理学》杂志上。

Modeling people’s lifetimes

模拟人们的一生

The team’s statistical models tested the impacts of loneliness and social isolation, both together and separately, on transitions between various states of cognitive impairment to the end of people’s lives.

该团队的统计模型测试了孤独和社会隔离的影响，无论是共同的还是单独的，在不同认知障碍状态之间的过渡到人们生命的尽头。

“This approach is crucial,” said Yoneda, “because cognitive impairment increases mortality risk, and both risks increase with age.”

“这种方法至关重要，”Yoneda说，“因为认知障碍会增加死亡风险，而这两种风险都随着年龄的增长而增加。”

Yoneda led the team of 24 researchers who analyzed data from 175,000 participants over the age of 50. Participants reported how frequently they felt lonely as well as how often they had contact with others.

Yoneda领导了一个由24名研究人员组成的团队，他们分析了17.5万名50岁以上参与者的数据。参与者报告了他们感到孤独的频率，以及他们与他人接触的频率。

The analysis found that loneliness was consistently associated with a higher risk of cognitive impairment and a shorter life, even after taking social isolation into account. Social isolation on its own was not consistently associated with cognitive decline and had only a weak association with a shorter life.

分析发现，即使将社会孤立考虑在内，孤独也始终与认知障碍的高风险和较短的寿命相关。社会孤立本身并不总是与认知能力下降有关，与寿命缩短只有微弱的联系。

A 10% increase in reports of feeling lonely was associated with an 8%-9% increased risk of severely impaired cognitive function and of transitioning from no impairment to mildly impaired cognitive function.

孤独感报告每增加10%，认知功能严重受损的风险就会增加8%-9%，认知功能从无受损过渡到轻度受损的风险也会增加8%-9%。

Reporting loneliness more frequently was also associated with a 3% lower likelihood of returning from mild cognitive impairment to no impairment. This suggest, researchers said, that alleviating loneliness may be important for recovery. Higher loneliness was the most consistent risk earlier in life even before measurable cognitive decline appeared, researchers said.

更频繁地报告孤独感也与从轻度认知障碍恢复到无损伤的可能性降低3%有关。研究人员说，这表明减轻孤独感可能对康复很重要。研究人员说，在认知能力出现明显下降之前，孤独感的增加在生命早期是最常见的风险。

“Loneliness may be most prominent in early stages of cognitive impairment, but is also a risk factor after impairment develops,” said the study’s supervising author Eileen K. Graham, an associate professor of medical social sciences at Northwestern University. “Lonelier individuals may be more likely to progress to more severe stages and less likely to recover.”

“孤独感可能在认知障碍的早期阶段最为突出，但在认知障碍发展后，孤独感也是一个风险因素，”该研究的监督作者、西北大学医学社会科学副教授艾琳·k·格雷厄姆说。“孤独的人更有可能发展到更严重的阶段，而不太可能康复。”

Reducing loneliness

减少孤独

The researchers said that finding ways to reduce loneliness, which would blunt its effects on cognitive impairment, could reduce the costs associated with care for individuals with dementia and other cognitive ailments.  

研究人员表示，找到减少孤独感的方法，可以减弱孤独感对认知障碍的影响，从而降低照顾痴呆症和其他认知疾病患者的成本。

They also said that individuals worried about cognitive decline can make efforts to strengthen their social connections with the people around them. For instance, hospitals and care organizations can incorporate screening tools that identify loneliness. Communities could create opportunities for older adults to engage with others and build a sense of belonging.

他们还表示，担心认知能力下降的人可以努力加强与周围人的社会联系。例如，医院和护理机构可以整合识别孤独感的筛查工具。社区可以为老年人创造与他人交往和建立归属感的机会。

Additional co-authors include Emorie Beck, assistant professor of psychology at UC Davis; as well as researchers representing the University of Southern California, Auburn University, UC Riverside, University College London, Western Virginia University, University of Limerick, Rush University Medical Center, Ohio University Heritage College of Osteopathic Medicine and Cornell University.

其他合著者包括加州大学戴维斯分校的心理学助理教授埃莫里·贝克；以及来自南加州大学、奥本大学、加州大学河滨分校、伦敦大学学院、西弗吉尼亚大学、利默里克大学、拉什大学医学中心、俄亥俄大学传统骨科医学院和康奈尔大学的研究人员。

The study was funded by the National Institutes of Health.

这项研究由美国国立卫生研究院资助。