The Journal of the American Medical Association (JAMA) reports two research projects into anabolic steroids and secondary wasting conditions.
Doctors at San Francisco General Hospital found that the anabolic steroid nandrolene decanoate increased kidney patients' body mass and reduced fatigue.
Researchers at the University of California at Berkeley found significant improvements in body weight and muscle strength in men with HIV-associated weight loss and normal testosterone levels.
Anabolic steroids - synthetic versions of the male hormone testosterone - are already used medically to rebuild tissues weakened by injury or disease, to assist in regaining or maintaining weight after illness and to aid recovery from breast cancer and osteoporosis in women.
However, they are most well-known for their use in sport where side effects include aggression, breast enlargement in men and menstrual irregularities in women.
Taken at excessive levels over long periods, they have been linked to liver damage and cancer.
Malnutrition
The San Francisco doctors studied 29 patients with kidney failure and evidence of malnutrition.
They were tested for weight, lean body mass, fatigue, grip strength, walking and stair-climbing times and treadmill performance.
The results were measured against patients given a placebo.
The researchers found that over a six-month period, patients given nadrolone gained an average of 5.7lbs more lean body mass than those given a placebo.
They also have higher serum creatinine levels. The researchers say this suggests the steroids increased their muscle mass.
The patients suffered significantly fewer symptoms of fatigue and a decrease in the time they took to walk to specific locations and climb stairs.
Only a few of the patients experienced minor side effects.
The researchers, led by Dr Kirsten Johansen, say more than 30% of dialysis patients need assistance in performing the normal activities of daily living and this has a major impact on their quality of life.
"This intervention may have an important impact on the functional capabilities and qualify of life of patients undergoing dialysis," they write.
Relatively low doses
The University of California study found that HIV-infected men with weight loss problems and normal testosterone levels had significant increases in lean tissue and muscle strength when given relatively low doses of the anabolic steroid oxandrolone.
They were also given therapy to equalise their testosterone and physiotherapy.
Restoration of lean body mass has proved difficult in people with HIV.
The study of 29 volunteers also found that use of combination therapy did not affect lean tissue response to steroids.
In an accompanying editorial in JAMA, Dr Adrian Dobbs of Johns Hopkins University School of Medicine in Baltimore urges caution over the use of anabolic steroids.
She calls for larger studies to be conducted, but adds: "Physicians need to be cognisant of the important problem of muscle-wasting and the contribution of reduced lean body mass to prognosis."
Background Briefings
Medical notes
Cancer and Aids vaccines move closer
(11 Mar 99 | Health)
Liver and kidney transplant is world first
(19 Feb 99 | Health)
Diabetes: The facts
(12 Jan 99 | Medical notes)
Aids charities to merge
(27 Jan 99 | Health)
Anabolic steroids
(23 Dec 98 | Medical notes)
Anabolic steroids
American Medical Association
National Aids Trust
St Peter's Trust for kidney research
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