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Dear Friends, Dr. Lieberman has just posted some articles that may of interest to Parkinsn members. I will send them in successive posts. Best, Kathrynne ***********A message from Ask the Doctor************** The NPF website is updated several times each week. Go to http://www.parkinson.org/whatsnew.htm to read recent articles regarding Parkinson disease. ****************************************************** This study will be presented at the American Academy of Neurology, April 2002, Denver Colorado The abstract was modified by Dr. Abe Lieberman to make it more readable for lay people Pramipexole (Mirapex) Versus Levodopa: Effects on PD Progression Assessed by Dopamine Transporter Imaging Parkinson Study Group New Haven, CT OBJECTIVE: To compare the rate of nigrostriatal dopamine degeneration after initial treatment with pramipexole or levodopa in early PD. BACKGROUND: Pramipexole (Mirapex) and levodopa are effective medications to treat motor symptoms of early PD. In vitro (cell culture) and animal studies suggest that pramipexole may protect dopamine neurons while levodopa, depending on the experimental conditions, may either protect dopamine neurons or accelerate dopamine neuron toxicity. Dopamine transporter imaging with [123I]b-CIT (a specific radio-active isotope)can be used to monitor the progressive dopamine neurone degeneration of PD. DESIGN/METHODS: Early PD patients (N = 82) enrolled in an earlier published study (JAMA 2000;284:1931-1938), underwent 4 sequential [123I]b-CIT SPECT scans during a 46 month period. Subjects were recruited at 17 movement disorder clinics in the US and Canada. Subjects were randomly assigned to receive pramipexole 0.5 mg (n=42) 3 times per day (total 1.5 mg per day) levodopa/carbidopa 25/100 mg 3 times per day. For patients with residual disability the dosage was escalated during the first 10 weeks and subsequently open label levodopa could be added. After 24 months of follow-up the dosage of study drug could be further modified. The primary outcome variable was the % change from baseline in striatal [123I]b-CIT uptake after 46 months evaluation. CIT measures the number of dopamine re-uptake receptors, receptors which are on neurons that start in the substantia nigra and end in either the caudate nucleus or the putamen. The greater the difference in CIT uptake at 48 months compared to baseline, The greater the number of dopamine neurons lost. The % changes and absolute changes in striatal, putamen, and caudate [123I]b-CIT uptake after 22 and 34 months were also assessed. Clinical severity of PD was assessed using the Unified Parkinson Disease Rating Scale (UPDRS) in the "defined off" state (this more closely approximates the underlying PD state). RESULTS: In the study sequential SPECT imaging showed a decline in [123I]b-CIT striatal uptake from baseline of 10.3 ± 9.8% at 22 months, 15.3 ± 12.8% at 34 months 20.7 ± 14.4% at 46 months, a loss of approximately 5.2% eacj year for all patients during the 46 month evaluation period. Comparison of the treatment groups demonstrated that the % loss in striatal [123I]b-CIT uptake from baseline was significantly reduced in the group initially treated with pramipexole compared to the group initially treated with levodopa: 7.1 ± 9.0% reduction in the group on pramipexole at 22 months versus 13.5 ±9.6% in the group on levodopa ( a 47% differnce) 10.9 ± 11.8% reduction in the group on pramipexole at 34 months versus 19.6 ± 12.4% reduction in the group on levodopa (a 44% difference) this difference was statistically significant 16.0 ±13.3% reduction in the group on pramipexole at 46 months versus 25.5 ±14.1% reduction in the group on levodopa (a 37% difference) this difference was statistically significant) The percent loss from baseline in striatal [123I]b-CIT uptake was correlated with the change from baseline in UPDRS at the 46 month evaluation CONCLUSIONS: Patients treated initially with pramipexole (Mirapex) demonstrated a relative reduction in the rate of loss of striatal [123I]b-CIT uptake of approximately 40% compared to those treated initially with levodopa during a 46-month evaluation period. These imaging data strongly suggest that treatment with pramipexole may slow and/or levodopa may accelerate the rate of loss of nigrostriatal dopamine neurons in early PD patients. This highlights the need to further compare imaging and clinical endpoints of PD progression in long-term studies. Supported By: Pharmacia Corporation and Boehringer Ingelheim -- Kathrynne Holden, MS, RD "Ask the Parkinson Dietitian" http://www.parkinson.org/ Author: "Eat well, stay well with Parkinson's disease" "Guidelines for Medical Nutrition Therapy for Parkinson's disease" http://www.nutritionucanlivewith.com/ ---------------------------------------------------------------------- To sign-off Parkinsn send a message to: mailto:[log in to unmask] In the body of the message put: signoff parkinsn