Striatal dopamine loss in early Parkinson’s disease: systematic review and novel analysis of dopamine transporter imaging

Heng, N., Malek, N., Lawton, M. A., Nodehi, A., Pitz, V. , Grosset, K. A., Ben-Shlomo, Y. and Grosset, D. G. (2023) Striatal dopamine loss in early Parkinson’s disease: systematic review and novel analysis of dopamine transporter imaging. Movement Disorders Clinical Practice, 10(4), pp. 539-546. (doi: 10.1002/mdc3.13687) (PMID:37070042) (PMCID:PMC10105104)

Abstract

Background: Neuropathological studies, based on small samples, suggest that symptoms of Parkinson's disease (PD) emerge when dopamine/nigrostriatal loss is around 50 to 80%. Functional neuroimaging can be applied in larger numbers during life, which allows analysis of the extent of dopamine loss more directly. Objective: To quantify dopamine transporter (DaT) activity by neuroimaging in early PD. Methods: Systematic review and novel analysis of DaT imaging studies in early PD. Results: In our systematic review, in 423 unique cases from 27 studies with disease duration of less than 6 years, mean age 58.0 (SD 11.5) years, and mean disease duration 1.8 (SD 1.2) years, striatal loss was 43.5% (95% CI 41.6, 45.4) contralaterally, and 36.0% (95% CI 33.6, 38.3) ipsilaterally. For unilateral PD, in 436 unique cases, mean age 57.5 (SD 10.2) years, and mean disease duration 1.8 (SD 1.4) years, striatal loss was 40.6% (95% CI 38.8, 42.4) contralaterally, and 31.6% (95% CI 29.4, 33.8) ipsilaterally. In our novel analysis of the Parkinson's Progressive Marker Initiative study, 413 cases had 1436 scans performed. For a disease duration of less than 1 year, age was 61.8 (SD 9.8) years, and striatal loss was 51.2% (95% CI 49.1, 53.3) contralaterally and 39.5% (36.9, 42.1) ipsilaterally, giving an overall striatal loss of 45.3% (43.0, 47.6). Conclusions: Loss of striatal DaT activity in early PD is less at 35-45%, rather than the 50-80% striatal dopamine loss estimated to be present at the time of symptom onset, based on backwards extrapolation from autopsy studies.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Grosset, Professor Donald and Pitz, Vanessa and Heng, Mr Nicholas and Grosset, Dr Katherine
• Authors: Heng, N., Malek, N., Lawton, M. A., Nodehi, A., Pitz, V., Grosset, K. A., Ben-Shlomo, Y., and Grosset, D. G.
• College/School: College of Medical Veterinary and Life Sciences > School of Medicine, Dentistry & Nursing; College of Medical Veterinary and Life Sciences > School of Psychology & Neuroscience
• Journal Name: Movement Disorders Clinical Practice
• Publisher: Wiley
• ISSN: 2330-1619
• ISSN (Online): 2330-1619
• Published Online: 06 February 2023
• Copyright Holders: Copyright © 2023 The Authors
• First Published: First published in Movement Disorders Clinical Practice 10(4): 539-546
• Publisher Policy: Reproduced under a Creative Commons License