title: Dopamine transporter imaging and SPECT in diagnostic work-up of Parkinson's disease: a decision-analytic approach.
abstract: As a diagnostic test for patients with suspected Parkinson's disease (PD), single photon emission computed tomography (SPECT) using [(123)I]FP-CIT tracer has better sensitivity but is more expensive than regular clinical examination (CE). Our objective was to evaluate the clinical and economic impacts of different diagnostic strategies involving [(123)I]FP-CIT SPECT. We developed a decision tree model to predict adequate treatment-month equivalents (ATME), costs, and incremental cost-effectiveness ratio (ICER) during a 12-month time horizon in patients with suspected PD referred to a specialized movement disorder outpatient clinic. In our cost- effectiveness analysis, we adopted the perspective of the German health care system and used data from a German prospective health care utilization study (n = 142) and published diagnostic studies. Compared strategies were CE only (EXAM+), SPECT only (SPECT+), SPECT following negative CE (SINGLE+), and SPECT following positive CE (DOUBLE+). Costs of SPECT amounted to euro;789 per investigation. Based on our model, expected costs (and ATME) were euro;946 (52.85 ATME) for EXAM+, euro;1352 (53.40 ATME) for DOUBLE+, euro;1731 (32.82 ATME) for SINGLE+, and euro;2003 (32.96 ATME) for SPECT+; performance of SPECT was induced in 0%, 54%, 56%, and 100% of the patients, respectively. DOUBLE+ was more effective and less expensive than SINGLE+ or SPECT+; thus these two do not offer reasonable choices. The ICER of DOUBLE+ compared to EXAM+ was euro;733 per ATME gained. In sensitivity analyses, the ICER of DOUBLE+ versus EXAM+ ranged from euro;63 to euro;2411 per ATME gained. Whether the diagnostic work-up of patients referred to a specialized movement disorder clinic with a high prevalence of PD should include [(123)I]FP-CIT SPECT depends on patient preferences and the decision maker's willingness to pay for adequate early treatment. SPECT should be used as a confirmatory test before treatment initiation and limited to patients with a positive test result in the clinical examination. These results should be adjusted to the specific setting and individual patient preferences.
authors.affiliation: Department of Neurology, Friedrich-Wilhelms-University, Bonn, Germany. richard.dodel@ukb.uni-bonn.de
authors.forename: Richard C
authors.initials: RC
authors.lastname: Dodel
authors.forename: Helmut
authors.initials: H
authors.lastname: Höffken
authors.forename: J Carsten
authors.initials: JC
authors.lastname: Möller
authors.forename: Bernhard
authors.initials: B
authors.lastname: Bornschein
authors.forename: Thomas
authors.initials: T
authors.lastname: Klockgether
authors.forename: Thomas
authors.initials: T
authors.lastname: Behr
authors.forename: Wolfgang H
authors.initials: WH
authors.lastname: Oertel
authors.forename: Uwe
authors.initials: U
authors.lastname: Siebert
mesh_terms: D000554:Ambulatory Care Facilities / Q000191:economics; D001921:Brain / Q000000981:diagnostic imaging*; D003362:Cost-Benefit Analysis / Q000706:statistics & numerical data; D003663:Decision Trees; D004295:Dihydroxyphenylalanine / Q000031:analogs & derivatives*; D050483:Dopamine Plasma Membrane Transport Proteins; D005858:Germany; D017048:Health Care Costs / Q000706:statistics & numerical data; D006801:Humans; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins / Q000032:analysis*; D009313:National Health Programs / Q000191:economics; D009419:Nerve Tissue Proteins; D009460:Neurologic Examination / Q000191:economics; D010300:Parkinson Disease / Q000000981:diagnostic imaging* / Q000191:economics; D011445:Prospective Payment System / Q000191:economics; D012017:Referral and Consultation / Q000191:economics; D015899:Tomography, Emission-Computed, Single-Photon / Q000191:economics
chemical_list: D050483:Dopamine Plasma Membrane Transport Proteins; D008562:Membrane Glycoproteins; D026901:Membrane Transport Proteins; D009419:Nerve Tissue Proteins; C043437:fluorodopa F 18; D004295:Dihydroxyphenylalanine