中老年人易脫水：感覺不到口渴

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, vice 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.

中老年人脫水的首要原因，也許也是最令人困惑的一個原因就是：他們不會感到口渴。在衰老過程中，口渴感會自然而然地降低，西奈山衛(wèi)生系統(tǒng)老年姑息醫(yī)學(xué)門診服務(wù)部的副主席兼西奈山醫(yī)院瑪莎斯圖爾特生活中心科菲老年醫(yī)學(xué)部的主任奧黛麗·春(Audrey Chun)博士說道。

While the mechanisms 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.

雖然造成這一現(xiàn)象的原因尚不明確，但65歲以上老年人的口渴程度通常遠(yuǎn)低于其身體實際需要的飲水量。由于口渴感降低，很多成年人的飲水量也開始降低，遠(yuǎn)比不上年輕時候，加利福尼亞州圣何塞市圣塔克拉拉谷醫(yī)療中心的住院醫(yī)學(xué)醫(yī)療主任桑杰·庫拉尼(Sanjay Kurani)博士說道。Plus, throughout the aging process, the kidneys naturally lose some of their ability to conserve 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 molecules. 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，在整個衰老過程中，腎臟儲水和濃縮尿的能力會逐漸地自然喪失，導(dǎo)致排尿時流失更多的水分。肌肉質(zhì)量的下降，稱為肌肉減少癥，也會降低身體的儲水量，因為肌肉是保持水分子的重要部位。2014年，Age and Ageing期刊上發(fā)表的一篇綜述表示：60歲及以上的老年人中，三分之一的人患有嚴(yán)重的肌肉損失。

Age-related health conditions can further predispose older adults to dehydration. Undiagnosed or uncontrolled Type 2 diabetes can increase urination, while urinary incontinence – and resulting anxieties – can cause a reduction in fluid consumption. Reduced mobility 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 Nutrients.

與年齡相關(guān)的健康狀況可能會使中老年人更易脫水。未確診的或不受控制的2型糖尿病會增加排尿，而尿失禁——以及由此產(chǎn)生的焦慮情緒——會導(dǎo)致液體攝入減少。行動不便也會降低人們的喝水次數(shù)和上廁所的頻率，庫拉尼說道。2018年發(fā)表在《營養(yǎng)》雜志上的一份研究表明，阿爾茲海默癥患者或老年癡呆患者也存在喝水不足的風(fēng)險。

What's more, commonly used over-the-counter and prescription medication can contribute to fluid losses as well. "Blood pressure medications such as diuretics are commonly associated with dehydration in the elderly," Kurani says. "Antihistamines and laxatives are also medications that can result in dehydration."

此外，經(jīng)常服用非處方藥和處方藥也會導(dǎo)致液體流失。“利尿劑等降壓藥通常與老年人脫水相關(guān)，”庫拉尼說道。“抗組胺藥和瀉藥也會導(dǎo)致脫水。”