Why Dehydration¹ Is Common in Older Adults

为什么中老年人更易脱水？

The first, and perhaps most perplexing, cause of dehydration in older adults is a lack of thirst. During the aging process, thirst sensation naturally decreases, says Dr. Audrey Chun, vice² chair of geriatric and palliative medicine outpatient services in the Mount Sinai Health System and director of Coffey Geriatrics at The Martha Stewart Center for Living at Mount Sinai Hospital.

中老年人脱水的首要原因，也许也是最令人困惑的一个原因就是：他们不会感到口渴。在衰老过程中，口渴感会自然而然地降低，西奈山卫生系统老年姑息医学门诊服务部的副主席兼西奈山医院玛莎斯图尔特生活中心科菲老年医学部的主任奥黛丽·春（Audrey Chun）博士说道。

While the mechanisms³ are not clear-cut, thirst levels in adults older than 65 are commonly far lower than indicative of the body's actual fluid needs. Because of this decreased thirst sensation, many adults do not drink as much as they did in their younger days, says Dr. Sanjay Kurani, medical director of inpatient medicine at Santa Clara Valley Medical Center in San Jose, California.

虽然造成这一现象的原因尚不明确，但65岁以上老年人的口渴程度通常远低于其身体实际需要的饮水量。由于口渴感降低，很多成年人的饮水量也开始降低，远比不上年轻时候，加利福尼亚州圣何塞市圣塔克拉拉谷医疗中心的住院医学医疗主任桑杰·库拉尼（Sanjay Kurani）博士说道。

Plus, throughout the aging process, the kidneys naturally lose some of their ability to conserve⁴ water and concentrate urine, leading to greater fluid losses through urination. A decline in muscle mass, referred to as sarcopenia, can also reduce how much water the body can store, as muscle functions as a significant holding area for water molecules⁵. One out of three adults age 60 and older suffers from severe muscle loss, according to a 2014 review published in Age and Ageing.

此外，在整个衰老过程中，肾脏储水和浓缩尿的能力会逐渐地自然丧失，导致排尿时流失更多的水分。肌肉质量的下降，称为肌肉减少症，也会降低身体的储水量，因为肌肉是保持水分子的重要部位。2014年，Age and Ageing期刊上发表的一篇综述表示：60岁及以上的老年人中，三分之一的人患有严重的肌肉损失。

Age-related health conditions can further predispose older adults to dehydration. Undiagnosed or uncontrolled Type 2 diabetes⁶ can increase urination, while urinary incontinence – and resulting anxieties – can cause a reduction in fluid consumption. Reduced mobility⁷ can cut down on how often people are willing to make trips to get water and use the restroom, Kurani says. People with Alzheimer's disease or dementia are also at an increased risk of not drinking enough water, according to 2018 research published in Nutrients⁸.

与年龄相关的健康状况可能会使中老年人更易脱水。未确诊的或不受控制的2型糖尿病会增加排尿，而尿失禁——以及由此产生的焦虑情绪——会导致液体摄入减少。行动不便也会降低人们的喝水次数和上厕所的频率，库拉尼说道。2018年发表在《营养》杂志上的一份研究表明，阿尔兹海默症患者或老年痴呆患者也存在喝水不足的风险。

What's more, commonly used over-the-counter and prescription⁹ medication can contribute to fluid losses as well. "Blood pressure medications such as diuretics are commonly associated with dehydration in the elderly," Kurani says. "Antihistamines¹⁰ and laxatives are also medications that can result in dehydration."此外，经常服用非处方药和处方药也会导致液体流失。“利尿剂等降压药通常与老年人脱水相关，”库拉尼说道。“抗组胺药和泻药也会导致脱水。”