Lithium is not effective in treating people with amyotrophic lateral sclerosis, also known as ALS or Lou Gehrig's disease, a new study has found.
The research is published in the August 11, 2010, online issue of Neurology
®, the medical journal of the American Academy of Neurology.
ALS is a progressive disorder of the nervous system causing weakness in muscles, including those controlling swallowing and breathing. For the majority of people, weakness tends to progress, causing death in three to five years.
People with ALS have been interested in lithium as a treatment after promising results were reported from a small Italian study.
The current study, also conducted in Italy, was stopped early due to an extremely high dropout rate from death, serious side effects and lack of benefit.
The study involved 171 people with ALS. One group of 87 people received a dosage of lithium considered to be therapeutic. The other group of 84 people received a dosage of lithium that was subtherapeutic, or lower than approved uses of lithium.
There was no difference between the two groups in how long the participants lived, how long until they were severely disabled or how well they were able to function with activities such as walking and swallowing. Of the 171 people, 117 or 68 percent had dropped out of the study due to death, side effects or because they thought the drug was ineffective.
"This discontinuation rate is two times higher than that in other recent studies for ALS drugs," said study author Adriano Chiò, MD, of the University of Turin in Italy and a member of the American Academy of Neurology. "This high dropout level, along with the relatively high frequency of side effects, raises serious doubts about the safety of this drug and also shows it to be ineffective for people with ALS."
ALS expert Carmel Armon, MD, MHS, of Tufts University School of Medicine and Baystate Medical Center in Springfield, Mass., points out in an accompanying editorial that this study did not use a true placebo. Two additional studies in progress that have some participants taking placebo may provide the definitive answer on whether lithium is effective in ALS, he said.