Stature estimation using the knee height measurement amongst Brazilian elderly

Area of Science:

• Gerontology
• Nutritional Science
• Anthropometry

Background:

• Stature is crucial for nutritional assessment in the elderly.
• Measuring stature is challenging in older adults who cannot stand.
• Knee height measurement offers an alternative for estimating stature.

Purpose of the Study:

• To assess the accuracy of the Chumlea et al. (1985) formula for estimating height in elderly Brazilians.
• To evaluate the formula's utility in calculating Body Mass Index (BMI) for this demographic.
• To determine the applicability of a Caucasian-based formula in a Brazilian population.

Main Methods:

• A sample of 621 community-dwelling elderly (≥60 years) in Viçosa, Brazil, was studied.
• Measured weight, height, and knee height (KH).
• Compared estimated vs. measured height and BMI using statistical tests (Student's t-test, Bland-Altman analysis) and Cohen's Kappa for BMI classification agreement.

Main Results:

• Average knee height (KH) measurements were higher than actual height measurements in the overall sample and specifically in women.
• The Chumlea formula led to an underestimation of Body Mass Index (BMI) in females and the entire study group.
• Significant differences were observed between genders for height measurements.

Conclusions:

• The Chumlea et al. formula is inadequate for estimating the height of the studied Brazilian elderly population.
• The formula's inaccuracy is particularly pronounced in elderly women.
• Estimated height and subsequent BMI calculations using this formula may not reliably reflect the nutritional status of this demographic.