Chapter 6 Nutrition Assessment of Older Adults

where WtE is estimated TBW, WtO is the observed body weight, and P is the percentage of TBW

represented by the missing limb segment(s). Example (24):

A below-the-knee amputation is 5.9%, or 0.059 of TBW.

Observed weight is 70 kg.

WtE = 70 kg ÷ (1 – 0.059) = 70 kg ÷ (0.941) = 74.4 kg

Studies document unique care issues for people with amputations (42) and slightly higher mortality risk for older adults (43).

Anthropometric Assessment of People With Paraplegia, Quadriplegia, and Tetraplegia

Spinal cord injuries, body composition changes such as water shifts, muscle atrophy from disease, and increased percentage of body fat affect the interpreta- tion of anthropometric measures. To calculate the ideal body weight (IBW) for a client who is paralyzed, first determine the IBW for a similar individual without paralysis. Next, subtract the appropriate value from that weight. The value subtracted depends on the degree of paralysis: For paraplegics, subtract 10 to 15 lb from the IBW of an individual without paralysis; for quadriple- gics, subtract 15 to 20 lb from the IBW of an individual without paralysis (44-46).

Comparative Standards for Height

and Weight Weight and body composition change with age. Weight tends to peak sometime during the fourth and fifth decade, hold steady in the sixth decade, with a gradual decrease beyond the seventh decade. Shifts in body composition are noted, and the proportion of body weight that is fat increases, averaging 30% of the TBW in older adults, as compared with 20% in younger people. The Hamwi formula (Box 6.4) is frequently used to calculate IBW for older adults (47). Table 6.3 (see page 94) illustrates the use of the Hamwi formula and frame size. Table 6.4 (see page 95) represents average weights and heights of older adults.(48) However, some older adult clients may have a target or usual weight that does not correlate with any table. An 85-year-old woman may never reach a weight of 100 lb, and an obese client may never achieve an “ideal” weight. The important issue is achieving a stable weight for a

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BOX 6.4 Hamwi Formula to Calculate Ideal Body Weight

Women: 100 lb + 5 lb for each inch of height above 5 ft Example: Height 5'6"

100 + (6 × 5) 100 + 30 = 130 IBW = 130 lb

Men: 106 lb + 6 lb for each inch of height above 5 ft Example: Height 5'10" 106 + (10 × 6) 106 + 60 = 166 IBW = 166 lb

For a large frame, add 10%. For a small frame, subtract 10%

Source: Adapted from reference 47.

period of six months or more. UBW is the preferred standard for older adults.

Weight Variances

The single most important clinical aspect leading to diagnosis of malnutrition is weight change and espe- cially unintentional weight loss (49). Variances in weight have significant impact on nutritional health; degree of weight change has positive correlations with impact on health status (50). When evaluating weight variances, it is important to determine possible causes, such as recent surgery or treatment initiation (eg, radia- tion or diuretic therapy affect weight status). Weight variances can also occur when caregivers fail to use correct procedures or weigh clients at different times of the day. Procedures and protocols for addressing weight change need to be in place to ensure accurate weights. Significant weight loss should be reported to both the physician and the RDN to make sure there are proper interventions. Weight loss is expressed as a per- centage of a resident’s usual weight or previous value.

Evaluating the Significance of Weight Loss The formula to determine weight change is as follows:

Weight loss % = [(UBW – CBW)/UBW] × 100

where UBW = usual body weight; CBW = current body weight.