Ace inhibitors can delay aging by affecting muscle function A group of commonly prescribed hypertension drugs shows promise for delaying muscle loss and disability in older adults, report researchers from Wake Forest University Baptist Medical Center in the March 14, 2002 issue of The Lancet.
"This is one of the first studies to suggest that a drug treatment could delay a decline in physical function," said lead researcher Graziano Onder, M.D. "Our results indicate that ACE inhibitor drugs could slow the process that leads to disability."
In a study of 641 older women with hypertension, those who regularly took ACE inhibitors had slower declines in walking speed and muscle strength than those taking other types of hypertension drugs, or taking no hypertension drugs. Declines in walking speed and muscle strength have been shown to predict the onset of disability, mortality, and nursing home and hospital admission in older adults. "If additional research confirms our hypothesis that ACE inhibitors have a positive effect on muscle function, they could become an important treatment for delaying the loss of physical function in older adults," said Onder.
ACE inhibitors had previously been shown to improve exercise tolerance in people with heart failure. Researchers thought this effect was related to the drug’s positive action on the cardiovascular system.
To test a theory that the drugs can affect muscle function, Onder and colleagues analyzed data from the Women’s Health and Aging Study (WHAS), started in 1991 by the National Institute on Aging (NIA) through a contract with Johns Hopkins University School of Medicine.
"The finding that medication use is associated with maintenance of walking ability in a group of partially disabled women is exciting," said Dr. Richard Havlik, M.D., MPH, Chief of NIA’s Laboratory of Epidemiology, Demography, and Biometry. "If the result is replicated in further research it could lead to a valuable intervention."
For the study, muscle strength and walking speed were measured over a three-year period in older women with hypertension. While seated in a chair, participants extended their knees, pushing as hard as they could against a device to measure the force. Walking speed was evaluated by walking for four meters.
Participants who continuously took ACE inhibitors had a significantly lower average decline in muscle strength (-2.2 lb) over the three years, as compared to continued/intermittent users of other antihypertensive drugs (-8.2 lb) and to never users of antihypertensive drugs (-8.6 lb). The average three-year decline in walking speed among ACE inhibitor users was 10 times lower than among the other groups.
"The effect needs to be confirmed by additional research," said Onder. "But it points to the possibility of ACE inhibitors being used as a first-line therapy for hypertension in older adults. Currently, these drugs are recommended only in certain situations."
Onder and colleagues plan to extend their research to include older men.
ACE (angiotensin converting enzyme) inhibitors include such drugs as Accupril, Captopril and Vasotec. They help reduce hypertension by blocking a protein that constricts blood vessels. Theories for how they could also impact muscle include the possibility that they can improve muscle efficiency, change a protein in muscle cells that makes them more resistant to fatigue, increase blood flow to muscles, and reduce inflammation that results in muscle wasting.
WHAS was initiated by NIA to better understand the causes and course of disability in older women. It was a prospective, observational study of 1,002 women age 65 years and older who were moderately to severely disabled, but not severely cognitively impaired, at study entry. These women represented the approximately one-third most disabled older women living in the community. These data were obtained from November 1992 to February 1995.