be clearly associated with adverse health outcomes (Reuben et al., 1995). The concept of malnutrition among older persons is more complicated because of the many settings along the continuum of care in which the elderly receive care.
community dwelling (including those receiving home care and Programs of All Inclusive Care (PACE),
institutionalized (nursing home) long-term care, and
The burden of acute and chronic disease differs across these settings, and nutritional requirements vary as a result. Moreover, an individual older person may move through many of these settings over the course of a single illness. Some measures of nutritional status vary in their degree of specificity for malnutrition across care settings. For example, changes in serum proteins among hospitalized older persons may be more reflective of inflammation and the acute-phase reaction than of malnutrition per se, whereas such changes may be more likely to indicate protein– energy undernutrition in community-dwelling persons. In addition, nursing home residents may have chronic inflammation, which complicates both the diagnosis and the management of malnutrition. Nevertheless, changes in these traditional indicators frequently have prognostic and clinical meaning and are therefore addressed in this chapter.
The most common nutritional disorder in older persons is obesity. Obesity has been defined variably by different organizations. Based on data from the Second National Health and Nutrition Examination Survey (NHANES II) (1976–1980), the threshold for obesity was defined as having a body mass index (BMI)1 exceeding 27.8 for men and 27.3 for women (NIH, 1985). Today, a BMI of 25 to 29.9 is considered to be overweight and a BMI of greater than or equal to 30 is considered obese (Meisler and St. Jeor, 1996; Mokdad et al., 1999; NHLBI, 1998).
The prevalence of overweight increases with age between the ages of 22 and 55 years but then stabilizes in women and declines in men (Van Itallie, 1985). The percentage of overweight and obese persons in the 65 to