DaT-uptake z-scores for Caudate and Striatum Predict Levodopa Requirement in Early Parkinson’s Disease
Katarina Rukavina1, Nicola Mulholland2, Ben Corcoran2, Juliet Staunton2, Magdalena Krbot Skoric3, Silvia Rota1, Alexandra Rizos2, K Ray Chaudhuri4
1King's College London, 2King's College Hospital, 3University Zagreb School of Medicine, 4King's College Hospital, London, UK
Objective:
We explored whether striatal dopaminergic availability may predict Levodopa Equivalent Daily Dose (LEDD) requirements in People with early Parkinson’s disease (PD, PwP).
Background:
Personalised medicine driven by clinical biomarkers is the state-of-art management approach for PD. Whether pattern of striatal dopaminergic deficiency (demonstrated by single-photon emission CT (SPECT) scanning with 123I-Ioflupane, DaTSCAN) could serve as a biomarker predicting levodopa requirement in early PD is not known.
Design/Methods:

Participants with early PD (disease duration (DD) ≤5 years, Hoehn and Yahr (HY) ≤3) who underwent DaTSCAN as a part of a clinical-diagnostic work up were enrolled in the “Non-motor Longitudinal International Study” (UK National Institute for Health Research Clinical Research Network Number 10084) and were included in this cross-sectional analysis. Specific DaTSCAN binding ratios were analyzed for each striatum, caudate and putamen and the z-scores were derived normalizing the images to age and gender-matched healthy controls from the European-Database-of-DaTSCAN-of-healthy-controls (ENC-DAT). The normality of data distribution was tested (One-sample Kolmogorov– Smirnov test) and descriptive statistics provided. Using linear regression analysis, we explored the impact of DaT-uptake z-scores for more severely affected putamen, caudate and striatum on the LEDD. Statistically significant predictors identified in the univariable analysis were included in the multivariable analysis with DD and HY as additional independent variables. (SPSS, Version 28).  

Results:

43 PwP (30.2 %female; age: 61.91±11.45years; DD: 2(0-5)years; HY: 2(1-3); LEDD: 424.27±342.62 mg) were assessed 19.12±13.11 months following the DaTSCAN. In a multivariable linear regression analysis, when adjusted for DD and HY, z-caudate (B=-134.073, 95% CI -262.715 - -5.431, p=0.042) and z-striatum (B=-162.137, 95% CI -306.306 - -17.967, p=0.028), were statistically significant predictors of LEDD, while z-putamen was not (p=0.086).

Conclusions:

DaT-uptake z-scores for caudate and striatum may serve as biomarkers that could predict LEDD requirement and guide treatment decisions towards personalized care for PwP.

10.1212/WNL.0000000000203240