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Physical Function in U.S. Older Adults Compared With Other Populations: A Multinational Study.

Dana A Glei¹, Noreen Goldman², Carol D Ryff³

¹1 Georgetown University, Santa Rosa, CA, USA.

Journal of Aging and Health

|February 23, 2018

Summary

Older Americans show comparable physical performance, including lung function and handgrip strength, to international peers. While gait speed is slower, overall physical decline is not worse than in England, Taiwan, or Costa Rica.

Keywords:

chair stand test gait speed nationally representative survey peak expiratory flow physical performance battery

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Area of Science:

Gerontology
Public Health
Comparative Physiology

Background:

Assessing physical performance in aging populations is crucial for public health.
International comparisons provide valuable insights into health disparities and lifestyle factors.
Previous studies have shown mixed results regarding the physical capabilities of older adults in the U.S. compared to other nations.

Purpose of the Study:

To compare physical performance metrics among older adults across multiple countries.
To determine if older Americans exhibit lower physical function compared to individuals in England, Taiwan, and Costa Rica.
To identify specific areas of physical performance where differences may exist.

Main Methods:

Utilized data from three U.S. national surveys and comparable international surveys.
Employed local mean smoothing to visualize age-specific performance profiles by sex.
Applied linear regression models to pooled data, controlling for age and height, to assess inter-country differences.

Main Results:

Lung function (peak expiratory flow) and handgrip strength in the U.S. were comparable to or higher than in other surveyed countries.
Americans performed similarly to English and Costa Rican participants on the chair stand test.
Gait speed in older Americans was generally slower than in the English population across most ages.

Conclusions:

Older Americans generally maintain physical performance levels comparable to their international counterparts.
Walking speed is a notable exception, with Americans exhibiting slower performance than the English.
The findings suggest that, apart from gait speed, there is limited evidence of diminished physical performance in older Americans relative to other developed nations.