[¹²³I]FP-CIT single photon emission computed tomography findings in drug-induced Parkinsonism.
Drug-induced parkinsonism (DIP) in patients treated with antipsychotic drugs is considered a form of post-synaptic parkinsonism, caused by D2-receptor blockade. Recent studies, however, carried out on small and heterogeneous patient samples, have shown that DIP may be associated with [(123)I]FP-CIT single photon emission computed tomography (SPECT) abnormalities, which are markers of dopamine nigrostriatal terminal defect. In the present study, outpatients fulfilling the DSM-IV criteria for schizophrenia and treated with antipsychotics for at least 6 months, were enrolled in order to estimate the prevalence of DIP and, among patients with DIP, the prevalence of [(123)I]FP-CIT SPECT abnormalities. Socio-demographic and clinical variables associated with the presence of DIP and SPECT abnormalities were also assessed. DIP was diagnosed in 149 out of 448 patients with schizophrenia (33%). Age, use of long-acting antipsychotics and a positive family history of parkinsonism were the only demographic variables significantly associated with the development of DIP. Neuroimaging abnormalities were found in 41 of 97 patients who agreed to undergo [(123)I]FP-CIT SPECT (42%). Only age differentiated this group of patients from those with normal imaging. These preliminary findings suggest that D2-receptor blockade may coexist with a dopamine nigrostriatal terminal defect, as assessed by [(123)I]FP-CIT SPECT abnormalities, in a relevant proportion of DIP patients. Longitudinal studies should be designed with the aim of improving our understanding of the mechanisms of pre-synaptic abnormalities in DIP patients and identifying specific treatment strategies.
Department of Neurological, Neuropsychological, Morphological and Motor Sciences, University of Verona, Italy.
Michele
M
Tinazzi
Andrea
A
Cipriani
Angela
A
Matinella
Antonino
A
Cannas
Paolo
P
Solla
Alessandra
A
Nicoletti
Mario
M
Zappia
Letterio
L
Morgante
Francesca
F
Morgante
Claudio
C
Pacchetti
Massimo
M
Sciarretta
Carlo
C
Dallocchio
Simone
S
Rossi
Maria
M
Malentacchi
Roberto
R
Ceravolo
Daniela
D
Frosini
Stelvio
S
Sestini
Tommaso
T
Bovi
Corrado
C
Barbui
D000328:Adult; D000368:Aged; D014150:Antipsychotic Agents / Q000009:adverse effects; D001921:Brain / Q000000981:diagnostic imaging*; D001931:Brain Mapping; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010302:Parkinson Disease, Secondary / Q000139:chemically induced / Q000000981:diagnostic imaging* / Q000503:physiopathology; D012559:Schizophrenia / Q000188:drug therapy; D012737:Sex Factors; D018709:Statistics, Nonparametric; D015899:Tomography, Emission-Computed, Single-Photon; D014326:Tropanes
D014150:Antipsychotic Agents; D014326:Tropanes; C087552:2-carbomethoxy-8-(3-fluoropropyl)-3-(4-iodophenyl)tropane