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Angiotensin-converting enzyme insertion/deletion genotype, exercise, and physical decline.
Stephen B Kritchevsky1, Barbara J Nicklas, Marjolein Visser
1The Sticht Center on Aging and Center for Human Genomics, Department of Internal Medicine, Wake Forest University School of Medicine, Winston-Salem, NC, USA. skritche@wfubmc.edu
JAMA
|August 11, 2005
Summary
Physical activity reduces mobility limitation in older adults. However, the angiotensin-converting enzyme (ACE) genotype influences this benefit, with the II genotype showing increased risk among active individuals.
Area of Science:
- Gerontology
- Genetics
- Exercise Physiology
Background:
- The angiotensin-converting enzyme (ACE) insertion (I)/deletion (D) genotype is linked to physical performance in young adults.
- Its role in exercise response and mobility limitation in older adults remains understudied.
Purpose of the Study:
- To investigate the interaction between ACE genotype and physical activity in predicting mobility limitation in well-functioning older adults.
Main Methods:
- The Health Aging and Body Composition (Health ABC) study enrolled 3075 adults aged 70-79.
- Mobility limitation was defined as difficulty walking 0.4 km or climbing 10 steps.
- Follow-up averaged 4.1 years.
Main Results:
- Physical activity (>1000 kcal/wk) reduced mobility limitation risk irrespective of ACE genotype.
- A significant interaction between ACE genotype and physical activity was observed (P = .002).
- Among active participants, the ACE II genotype was associated with a higher risk of mobility limitation (adjusted rate ratio, 1.45) compared to ID/DD genotypes, particularly with weightlifting.
Conclusions:
- Older adults with ACE DD or ID genotypes who exercised had a lower risk of mobility limitation than those with the II genotype.
- Exercise consistently reduced mobility limitation risk across all ACE genotypes.
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