Provided Courtesy of Nutrition411.com
Assessment of
Declining Health Status
Contributed by Shawna Gornick-Ilagan, MS, RD, CWPC, CHES
Updated by Nutrition411.com staff
Review Date 4/14
G-1223
How to Identify Declining
Health Status
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Body mass index (BMI)
Percent weight change
Percent usual body weight
Arm muscle area
Subjective global assessment
How to Identify Declining
Health Status (cont’d)
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Body mass index (BMI)
Percent weight change
Percent usual body weight
Arm muscle area
Subjective global assessment
BMI
• 2.2 lb in 1 kg
• 2.54 cm in 1″
• 100 cm in 1 m
cm=centimeter, kg=kilogram, lb=pound, m=meter
Category
BMI Range kg/m2
Severe thinness
Moderate thinness
Mild thinness
Normal
Overweight
Obese Class I
Obese Class II
Obese Class III
Source: http://www.who.int/en/
<16
16-16.99
17-18.49
18.5-24.99
25-29.99
30-34.99
35-39.99
40+
BMI Online Resources
http://www.nhlbi.nih.gov/guidelines/obesity/BMI/
bmicalc.htm
http://www.consumer.gov/weightloss/bmi.htm
http://apps.nccd.cdc.gov/dnpabmi/Calculator
.aspx (for ages 2-19)
http://www.cdc.gov/nccdphp/dnpa/healthy
weight/assessing/bmi/adult_BMI/english_bmi_cal
culator/bmi_calculator.htm (ages 20+)
BMI Printable Chart
www.nhlbi.nih.gov/guidelines/obesity/bmi_tbl.pdf
Anthropometrics
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BMI
Percent weight change
Percent usual body weight
Arm muscle area
Subjective global assessment
Percent Weight Change
• Percent recent weight change=
Usual Weight – Actual Weight X 100 =10%
Usual Weight
• Mary Jane was 150 lb last time you saw her
3 weeks ago
• Today you visit her and she is 135 lb
• What is her percent weight change?
Percent Weight Change
(cont’d)
• Percent recent weight change=
Usual Weight (150) – Actual Weight (135) X100
Usual Weight (150)
• Mary Jane was 150 lb last time you saw her
3 weeks ago
• Today you visit her and she is 135 lb
• What is her percent weight change?
Percent Weight Change
(cont’d)
• Significant weight loss:
− 5% loss over 1 month
or
− 7.5% loss over 3 months
or
− 10% loss over 6 months
• Severe weight loss:
− 5% loss over 1 month
or
− >7.5% loss over 3 months
or
− 10% loss over 6 months
Source: Blackburn et al, 1977.
Declining Weight Status
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BMI
Percent weight change
Percent usual body weight
Arm muscle area
Subjective global assessment
Usual Body Weight
• The stable body weight of the person
during the past 6 to 12 months
% Usual Body Weight
(cont’d)
• % Usual Body Weight=
Actual Body Weight  100
Usual Body Weight
% Usual Body Weight
(cont’d)
Mildly malnourished
85%-90%
Moderately malnourished 75%-84%
Severely malnourished
<74%
Absolute minimum weight 48%-55%
for survival
Declining Health Status
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BMI
Percent weight change
Percent usual body weight
Arm muscle area
Subjective global assessment
Arm Muscle Area (AMA)
• AMA is an estimate of overall muscle mass
• The National Health and Nutritional
Examination Survey (NHANES) data
indicate a depletion of lean body mass (ie,
malnutrition and/or declining health status)
• Assumptions:
– Arm, muscle, bone are circular
– TSF is 2 the thickness of fat
– Bone area is constant
TSF=triceps skinfold
AMA (cont’d)
• AMA is a better predictor of mortality than
BMI in chronic obstructive pulmonary
disease patients
Source: Soler-Cataluña JJ. Chest. 2005;128(4):2108-2115.
What You Need
to Calculate AMA
• The equation:
[MAC–(π x TSF)]2
4π
– Where π=3.14
• MAC—mid-arm circumference (cm)
• TSF—triceps skinfold (cm)
• Calculator
• Chart to interpret results
Finding the Point to
Measure the MUAC or MAC
• Conduct on the
nondominant arm
• Bend elbow 90 degrees
• Measure the distance from
the boney protrusion on
the shoulder (acromion)
and the point of the elbow
(olecranon process)
• Mark the midpoint
MAC=mid-arm circumference, MUAC=mid-upper arm circumference
Mid-Upper Arm Muscle
Circumference
Triceps Skinfold (TSF)
• Technique: Use right side
Final Step
• Put results into AMA equation
• AMA=[MAC–(π x TSF)]2
4π
• Use Appendix R from Lee and Nieman’s
Nutritional Assessment book to calculate
results by finding the closest number in the
appropriate category
Guidelines for Interpreting
Percentile Values
for Arm Muscle Area
Category
Percentile
Wasted
<5th percentile
Below average
5th-15th percentile
Average
15th-85th percentile
Above average
85th-95th percentile
High muscle
>95th percentile
Practice Example
(make everything cm)
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Age 51
If the MAC=12.5″ x 2.54=31.75 cm
If the TSF=30 mm Hg=3 cm
AMA=[MAC–(π x TSF)]2
4π
• AMA=31.75 cm–(3.14x3 cm)=22.33=squared
498.62 =39.69 cm2
12.56
• Individual is in the 10th percentile
mm Hg=millimeters of mercury
Result
• Patient is at increased nutritional risk secondary
to AMA results of 10%, categorized as below
average
Category
Percentile
Below average
5th-15th percentile
• One negative: AMA not validated in people who
are older than 75 years of age
Declining Weight Status
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BMI
Percent weight change
Percent usual body weight
Arm muscle area
Subjective global assessment
Subjective Global
Assessment (SGA)
SGA:
• Is truly a subjective means of assessing
nutritional status, which corresponds to the
subjective opinion of the patient’s
nutritional status
• Classifies the patient as A, B, or C, which is
based on the subjective ratings in two
broad areas:
– Medical history
– Physical examination
SGA (cont’d)
• SGA is not a scoring system—not
appropriate to score or add the number of
A, B, and C ratings to arrive at the overall
SGA classification
• If a patient has more B and C ratings,
malnutrition is more likely
• A well-nourished patient will have ratings
on the left-hand side of the SGA scoring
sheet
Questions?