A reanalysis of a study that evaluated the use of steroids to treat inflamed optic nerves provides evidence that corticosteroid injections may delay the onset of multiple sclerosis (MS).
A chameleon among diseases, MS defies both understanding and treatment. This disorder can begin and progress erratically It is linked to the appearance of patches in the brain where myelin, the nerve cells' protective sheath, has disintegrated. Physicians can treat symptoms, but rarely can they slow the disease's progression (SN: 3/27/93, p. 197).
A diagnosis requires the separate development of two neurological problems, such as memory loss, tremors, vision problems, or partial paralysis. Recently. scientists have begun to use magnetic resonance imaging (MRI) to track the progression of this disease.
One of these neurological problems, optic neuritis, leads to sudden temporary loss or impairment of vision. Between 35 and 75 percent of those with optic neuritis later develop MS, says Donald H. Silberberg of the Hospital of the University of Pennsylvania in Philadelphia. At other times, the optic nerve becomes inflamed for different reasons.
From 1988 to 1991, 15 medical centers treated about 450 people diagnosed with their first case of optic neuritis. For two weeks, the participants got either steroid shots for three days and then pills, steroid pills alone, or pills containing no medication. The study revealed that injected steroids, followed by pills, provided marginal long-term benefit, says Roy W. Beck, an ophthalmologist at the Jaeb Center for Health Research, Inc. in Tampa, Fla. Those receiving injections simply recovered their sight a week or so faster than those who took pills. Eventually, all groups recovered equally well, a result suggesting steroids were unnecessary
That advice may now change. The researchers have gone back and determined how many of the people who showed no signs of MS at the time they received treatment later developed this disease. "We wanted to look at indicators of risk for MS," says Beck, who headed the research project.
To their surprise, about 7.5 percent of the 135 people who got shots and pills developed MS, while 14.7 percent of the 129 patients who took steroid pills only and 16.7 percent of the 126 who took pills with no medication got MS within two years, the group reports in the Dec. 9 NEW ENGLAND JOURNAL OF MEDICINE.
However, after two years, even those who received steroid shots began developing MS at the same rate as those in the other study groups, Beck says. He and his colleagues suspect that the shots present the immune system with a high enough dose of steroids to somehow counter the initial inflammatory response and curtail damage. This effect eventually wears off, however.
Some doctors already treat their MS patients with steroids, and a few small studies show that steroids can speed an MS patient's recovery from a flare-up of the disease, Beck says. "Our findings are at least supportive of this use."
Each participant received an MRI brain scan at the beginning of the study. The eye-study data confirm that these scans can help identify those at risk of developing MS, says Beck. Almost 25 percent of participants with abnormal scans had MS within two years, while just 5 percent of those with normal scans did. The more abnormal the scan, the more likely the development of MS.
"[The report] supports treatment with intravenous steroids, particularly [in] people with optic neuritis and abnormal MRI [scans]," comments Stephen C. Reingold of the National Multiple Sclerosis Society in New York City.
However, both Reingold and Silberberg caution that this study was not designed to assess a treatment for MS. Because patients knew when they received injections, the results could be biased, they warn. Also, the number of MS patients in each group was relatively small.
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