Читать книгу Pathy's Principles and Practice of Geriatric Medicine - Группа авторов - Страница 386

Weight loss is an important clinical sign included in the impaired general condition syndrome with asthenia and anorexia. This finding should lead to an etiological investigation. Unintentional weight loss is also included in the frailty phenotype described by Fried et al. with four other criteria: low gait speed, exhaustion, decreased muscle strength, and decreased physical activity.¹

Weight loss, isolated or included in the frailty syndrome, is common in older adults and is a harbinger of poor outcomes. A loss of 10% or more of body weight between age 50 and old age is associated with a 60% increase in mortality compared with people with stable weight.² Involuntary weight loss greater than 4% of body weight is an independent predictor of increased mortality in older community‐dwelling male veterans. Over a two‐year follow‐up period, mortality rates were substantially higher in the 13% of the population with involuntary weight loss (28%) than in those who did not lose weight (11%), even after adjusting for baseline age, body mass index (BMI, the weight in kilograms divided by the height in metres squared), tobacco use, and other health status and laboratory measures.³

Weight loss is strongly associated with a 76% increase in mortality risk among home‐bound older adults, along with male gender and age. This effect of weight loss persists after adjusting for initial BMI, smoking, health status, and functional status.⁴

In nursing home residents, a 10% loss of body weight over a six‐month interval strongly predicted mortality in the ensuing six months.⁵ When compared with controls, the 16% of subjects who lost at least 5% of their body weight were 4.6 times more likely to die within one year.⁶ In another study of long‐term care residents, a 10‐fold increased risk for death was seen for people who lost 5% of their body weight in any month compared with those who gained weight.⁷

Weight loss is also associated with a decline in functional status. Weight loss of more than 5% in community‐dwelling women age 60–74 was associated with a twofold increase in risk of disability over time, compared with women who did not lose weight, after adjustments for age, smoking, education, study duration, and health conditions.⁸ The Health Aging and Body Composition (ABC) study provided longitudinal data of weight, BMI, body composition, and function in a cohort of older people (70–79) who were functionally independent at baseline.⁹ Weight loss during the first four‐year period was associated with loss of lean and fat body mass; but during weight gain episodes less gain in lean body mass than loss during weight loss was observed, particularly in obese men.¹⁰ In the Health ABC study, nine‐year BMI trajectories showed general trends in BMI decline in women and men. However, men who were obese at baseline had a more significant decline in gait speed and strength than others, with no association with loss of lean body mass. Obese women had more significant lean body mass loss than others, but there was no association between BMI trajectories with function or physical performance according to time.¹¹ Weight loss and undernutrition are also related to functional decline in nursing home residents.¹²

Body weight and weight adjusted for height (BMI) are easily obtained clinical measurements that can predict adverse outcomes in older people.