Heart valve disease appears to be relatively common in Parkinson’s disease patients treated with pergolide (Permax), according to results of a new study. Evidence suggests that the degree of damage correlates with lifetime dose of the drug, but the effects may be reversible.

Pergolide belongs to a class of drugs called dopamine agonists. It is derived from ergot, a substance obtained from plants, and works by acting in place of dopamine, a natural substance in the brain needed to control movement.

Several cases of valvular heart disease associated with pergolide treatment have been reported recently, but the prevalence of the condition is unknown, Dr. D. G. Baseman of the University of Texas Southwestern Medical School, Dallas, and colleagues report in journal Neurology.

Using the clinical database of the Clinical Center for Movement Disorders at their institution, the investigators identified 82 patients who were confirmed to be currently taking the drug.

Forty-six of these patients underwent cardiac evaluation, and scores for heart valve regurgitation, or backward flow of blood, were compared with those from a comparison (control) group of patients of the same age participating in the Framingham Heart Study.

Baseman’s team observed some degree of valvular regurgitation in 89 percent of the patients. The risk of abnormal valves was up to three times that observed in the control group, and there was an estimated 14-fold increased risk of regurgitation of heart’s the tricuspid valve. Valve scores increased with increased duration of pergolide use, the authors note.

In three patients with disabling heart disease, cessation of the drug was followed by improvements on cardiac tests.

“We believe that dopamine agonist therapy should be initiated with a nonergot drug,” Baseman’s group concludes. “In those currently taking pergolide, consideration should be given to switching to a nonergot agonist until the safety of pergolide can be firmly established.”

SOURCE: Neurology, July 27, 2004.