Nicotine therapy might improve the course of Parkinson's disease. This observational study evaluated the performance of dopamine transporter imaging in follow-up patients under nicotine therapy.
Six Hoehn and Yahr stage III patients underwent 123I-FP-CIT imaging prior to, 3 months, and 1 year after the onset of nicotine therapy. Nicotine was administered transdermally with increasing daily doses during 3 months (up to 105 mg/day) and decreased progressively. On co-registered magnetic resonance imaging, striatal regions of interest were drawn and binding potentials of 123I-FP-CIT were calculated. Changes in Unified Parkinson's Disease Rating Scale-III over time were compared with binding potentials using regression analysis.
All patients improved motor scores at 3 months (−65±22% ‘off’, −89±12% ‘on’) and most received fewer dopaminergic drugs (−30% dosage in average). Motor improvement persisted to a lesser extent at 1 year (−39±31% ‘off’, −13±43% ‘on’), partly because one patient stopped the treatment. Interestingly, the decrease in binding potentials (−4.0±10.5%) was slower than that expected in Parkinsonian patients (usually −10% per year) and was inversely correlated with Unified Parkinson's Disease Rating Scale-III improvement, r = 0.83 ‘off’ and 0.91 ‘on’.
This observational study emphasizes a potential effect of nicotine therapy on striatal dopamine transporter density, which may be interpreted as direct pharmacological effect or deceleration of neuronal loss.
Departments of aNuclear Medicine
dClinical Research Unit, H. Mondor Hospital, AP-HP, Paris 12 University, Créteil, France
eDepartment of Computer Science, University of Southern California, Los Angeles, California, USA
Correspondence to Emmanuel Itti, MD, PhD, Service de Médecine Nucléaire, CHU Henri Mondor, 51 Avenue du Maréchal de Lattre de Tassigny, 94010 Créteil, France
Tel: +33 1 49 81 27 80; fax: +33 1 49 81 27 94;
Received 5 September 2008 Revised 3 December 2008 Accepted 4 February 2009