Donini Lorenzo M, Savina Claudia, Cannella Carlo
Istituto di Scienza dell'Alimentazione, Università di Roma La Sapienza, Rome, Italy.
Int Psychogeriatr. 2003 Mar;15(1):73-87. doi: 10.1017/s1041610203008779.
Although a high prevalence of overweight is present in elderly people, the main concern in the elderly is the reported decline in food intake and the loss of the motivation to eat. This suggests the presence of problems associated with the regulation of energy balance and the control of food intake. A reduced energy intake causing body weight loss may be caused by social or physiological factors, or a combination of both. Poverty, loneliness, and social isolation are the predominant social factors that contribute to decreased food intake in the elderly. Depression, often associated with loss or deterioration of social networks, is a common psychological problem in the elderly and a significant cause of loss of appetite. The reduction in food intake may be due to the reduced drive to eat (hunger) resulting from a lower need state, or it arises because of more rapidly acting or more potent inhibitory (satiety) signals. The early satiation appears to be predominantly due to a decrease in adaptive relaxation of the stomach fundus resulting in early antral filling, while increased levels and effectiveness of cholecystokinin play a role in the anorexia of aging. The central feeding drive (both the opioid and the neuropeptide Y effects) appears to decline with age. Physical factors such as poor dentition and ill-fitting dentures or age-associated changes in taste and smell may influence food choice and limit the type and quantity of food eaten in older people. Common medical conditions in the elderly such as gastrointestinal disease, malabsorption syndromes, acute and chronic infections, and hypermetabolism often cause anorexia, micronutrient deficiencies, and increased energy and protein requirements. Furthermore, the elderly are major users of prescription medications, a number of which can cause malabsorption of nutrients, gastrointestinal symptoms, and loss of appetite. There is now good evidence that, although age-related reduction in energy intake is largely a physiologic effect of healthy aging, it may predispose to the harmful anorectic effects of psychological, social, and physical problems that become increasingly frequent with aging. Poor nutritional status has been implicated in the development and progression of chronic diseases commonly affecting the elderly. Protein-energy malnutrition is associated with impaired muscle function, decreased bone mass, immune dysfunction, anemia, reduced cognitive function, poor wound healing, delayed recovery from surgery, and ultimately increased morbidity and mortality. An increasing understanding of the factors that contribute to poor nutrition in the elderly should enable the development of appropriate preventive and treatment strategies and improve the health of older people.
尽管老年人中超重现象普遍存在，但老年人主要关注的是据报道的食物摄入量下降以及进食动力的丧失。这表明存在与能量平衡调节和食物摄入量控制相关的问题。能量摄入减少导致体重减轻可能是由社会因素或生理因素，或两者共同作用引起的。贫困、孤独和社会隔离是导致老年人食物摄入量减少的主要社会因素。抑郁症通常与社交网络的丧失或恶化有关，是老年人常见的心理问题，也是食欲不振的重要原因。食物摄入量的减少可能是由于需求状态较低导致进食动力（饥饿感）降低，或者是由于作用更快或更强的抑制性（饱腹感）信号引起的。早期饱腹感似乎主要是由于胃底适应性舒张减少导致胃窦早期充盈，而胆囊收缩素水平和效力的增加在衰老性厌食中起作用。中枢进食动力（阿片类和神经肽Y的作用）似乎随着年龄的增长而下降。身体因素，如牙齿不好和假牙不合适，或与年龄相关的味觉和嗅觉变化，可能会影响食物选择，并限制老年人所吃食物的类型和数量。老年人常见的医学病症，如胃肠道疾病、吸收不良综合征、急慢性感染和高代谢，常常导致厌食、微量营养素缺乏以及能量和蛋白质需求增加。此外，老年人是处方药的主要使用者，其中一些药物会导致营养物质吸收不良、胃肠道症状和食欲不振。现在有充分的证据表明，尽管与年龄相关的能量摄入减少在很大程度上是健康衰老的生理效应，但它可能会使心理、社会和身体问题的有害厌食效应更容易发生，而这些问题随着年龄的增长越来越频繁。营养状况不佳与通常影响老年人的慢性疾病的发生和发展有关。蛋白质 - 能量营养不良与肌肉功能受损、骨量减少、免疫功能障碍、贫血、认知功能下降、伤口愈合不良、手术后恢复延迟以及最终发病率和死亡率增加有关。对导致老年人营养不良的因素的日益了解应该能够制定适当的预防和治疗策略，并改善老年人的健康状况。
