Cardiovascular effects of levodopa in aged versus younger patients with Parkinson's disease

The cardiovascular effects of prolonged administration of levodopa were studied in 54 men and women with Parkinson's disease; 23 of them were younger than 70 and 31 were 70 or older. The patients were evaluated clinically before treatment was started and at regular intervals thereafter. The average optimal dosage of levodopa for both age groups was 3.0 and 2.5 gm per day, respectively, during an average treatment period of 20.7 months. Eleven patients showed hypotension (systolic BP of 105 mm Hg or less) that was not related to dosage; in only 6 did the drug have to be permanently discontinued because of syncope; 3 of this group had an associated psychiatric disorder. Four patients had pretreatment hypertension; in 3 the BP fell to normal during therapy; in the remaining patient the hypertension persisted and was successfully treated by an antihypertensive drug. In 5 patients an occasional atrial or ventricular ectopic beat was noted both before and during levodopa therapy but no therapeutic intervention was required. Thirty of the 46 patients with adequate ECG follow-up did not show any significant changes; 5 others showed an increase, and 11 a decrease in myocardial ischemia. Thus the administration of levodopa in elderly patients with or without heart disease is a relatively safe procedure. The only exception would be patients over 70 years of age with a history of previous myocardial infarction. In this group there seems to be a higher incidence of clinically significant hypotension. In such patients, levodopa therapy should be carried out with great caution.