Researchers Question Drug For Chronic Fatigue Syndrome

In a preliminary study published in 1995, Peter Rowe, M.D., leader of the Johns Hopkins team, reported that many patients diagnosed with chronic fatigue syndrome (CFS) developed lightheadedness, fatigue, and sometimes fainted when they stood for prolonged periods of time. When tilted head-up on a special diagnostic table, most patients developed a sudden drop in blood pressure known as neurally mediated hypotension (NMH). Some study participants reported substantial relief in their lightheadedness and CFS symptoms when treated with a combination of an increase in dietary sodium chloride (table salt), fludrocortisone, and other medications. Fludrocortisone helps to maintain a normal blood pressure by reducing the loss of sodium from the bloodstream.

The researchers conducted the current, more rigorous study to determine whether isolating one component of the treatment – fludrocortisone – would be equally effective in treating symptoms. Over nine weeks, 50 adults with both CFS and NMH received fludrocortisone, and 50 received a placebo. Neither group took supplemental sodium. During the study, investigators and study participants were unaware of who received the fludrocortisone or the placebo. At the end of the treatment period, 14 percent of those treated with fludrocortisone described a notable improvement in overall well-being, compared with 10 percent in the placebo group, a difference that was not deemed statistically significant by researchers.

Since this current study began in 1996, other studies have identified four drugs effective in treating some people with recurrent fainting due to NMH.

"One of these medications may prove more effective than fludrocortisone in treating NMH among those with CFS," says Rowe. "Over 60 percent of the patients we screened for this study had abnormal heart rate and blood pressure responses during tilt testing, and most had worse symptoms brought on early in the test. Their responses to upright posture suggest a need to better define the optimal way to treat NMH in people with CFS. In the patients we studied, clearly, fludrocortisone alone was insufficient."

CFS affects approximately one of every 250 Americans. Although profound fatigue is a defining feature of the syndrome, other important problems include difficulty with memory and concentration, sleep disturbance, muscle aches, and headaches. The causes of CFS are not known. Treatment is aimed at relieving individual symptoms. No medication has been found effective in treating the disorder as a whole.

The study was funded by grants from the National Institute of Allergy and Infectious Disease, the Johns Hopkins Outpatient General Clinical Research Center, and the Chronic Fatigue and Immune Dysfunction Syndrome Association of America, Inc.