Underwater Weighing Familiarization Program for Adults with Prader-Willi Syndrome

Area of Science:

• Body composition analysis
• Pulmonary function testing
• Syndromic disorders

Background:

• Accurate body composition assessment is crucial for managing metabolic complications in Prader-Willi syndrome (PWS).
• Underwater weighing (UWW) and residual lung volume (RV) are standard methods, but require familiarization for reliable results, especially in specific populations like PWS.
• Developing effective familiarization protocols is essential for optimizing measurement accuracy in clinical research and practice.

Purpose of the Study:

• To evaluate the efficacy of a novel underwater weighing (UWW) and residual lung volume (RV) familiarization program for adults with Prader-Willi syndrome (PWS).
• To assess the reliability and consistency of body fat percentage and RV measurements following the familiarization protocol.
• To determine the most reliable method for assessing body composition in adults with PWS.

Main Methods:

• A cohort of 15 adults with PWS (10 males, 5 females) underwent a structured UWW familiarization program.
• Body fat percentage was measured using UWW across four sessions post-familiarization.
• Residual lung volume (RV) was measured concurrently with UWW, with reliability assessed using intraclass correlation coefficients (ICC).

Main Results:

• No significant differences were found in percent body fat derived from UWW across the four sessions (F(3, 27) = 0.80, p = .505), indicating high reliability (R = .93).
• A significant difference was observed in RV measurements across sessions (F(3, 27) = 5.25, p = .006), with lower reliability (R = .65).
• The familiarization program demonstrated effectiveness for UWW body fat assessment but highlighted variability in RV measurements.

Conclusions:

• The UWW familiarization program is recommended for improving the accuracy and reliability of body fat percentage measurements in adults with PWS.
• Measuring RV in adults with PWS presents challenges in consistency, suggesting that predicting RV may be a more viable alternative.
• Further research into predictive models for RV could enhance body composition assessments in this population.