The substantial diabetes risk reduction seen in association with Parkinson's disease was driven by levodopa users, while the risk for developing diabetes was not altered for Parkinson's disease patients not using levodopa.
This difference was driven by differences in the daily dose of levodopa, while there were no differences in the doses of dopamine agonists (Supplementary Table 1).
Mean values from spherical VOIs centered on these peaks show that PD control patients have decreased rCBF after levodopa, while mood fluctuators do not (repeated measures ANOVA, F1,19=5.086, p<0.04; post hoc Scheffe tests indicate a decrease with levodopa in the motor fluctuator group at p<0.06 but p>0.25 for all other comparisons).
That said, recordings were made on levodopa, while patients' clinical state was as near normal as possible.
The first group was cotreated with intraperitoneal MK-801 0.1 mg/kg and levodopa twice daily while the second group was cotreated with vehicle and levodopa twice daily.
3 While levodopa alleviates the main motor symptoms of PD, long-term treatment with the drug causes abnormal involuntary movements, ie, levodopa-induced dyskinesias, in a subset of patients.
Sixty-seven (64.4%) were on 2 anti-Parkinsonian medications, with over 90% of this group receiving the benzhexol and levodopa combination, while 23.1% were on a combination of 3 medications.
The primary contrast compared response to levodopa between the two patient groups.
Levodopa remains the mainstay of treatment for PD over 40 years after its introduction.
Supporting this view, mood response to a dose of levodopa precedes the improvement in motor function (Maricle et al, 1995a).
