Correlation between striatal vesicular monoamine transporter 2 and the non-motor symptoms in Parkinson′s disease / 中华核医学与分子影像杂志

ABSTRACT

Objective:To explore the relationship between vesicular monoamine transporter 2(VMAT2) density in the striatum and the non-motor symptoms(NMSs) in patients with Parkinson′s disease(PD).Methods:From December 2018 to December 2019, 29 normal controls (16 males, 13 females, age (48.8±14.2) years), 31 patients with PD at the Hoehn-Yahr (mH-Y) Ⅱ stage (16 males, 15 females, age (53.4±8.5) years) and 36 patients with PD at mH-Y Ⅲ stage (19 males, 17 females, age (63.1±8.2) years) in the First Affiliated Hospital of Sun Yat-sen University were prospectively enrolled in this study. All subjects underwent 18F-fluoropropyl-(+ )-dihydrotetrabenazine( 18F-FP-(+ )-DTBZ, 18F-AV133) PET/CT imaging, then the specific uptake ratios (SURs) of striatal subregions were measured with the occipital cortex as the reference background region. The clinical data, laboratory data and imaging results were collected. The NMSs of each patient were evaluated with Hamilton Anxiety Rating Scale (HAMA), Hamilton Depression Rating Scale (HAMD), Parkinson′s Disease Sleep Scale (PDSS), Montreal Cognitive Assessment (MoCA), Parkinson′s Disease Quality of Life Questionnaire (PDQL) and Non-Motor Symptoms Scale (NMSS). The independent-sample t test and one-way analysis of variance (the least significant difference t test) were used to compare data differences. Finally, the association of the striatal SURs with the clinical symptom scores were evaluated with Pearson correlation analysis and multivariable stepwise regression analysis. Results:Significant differences were found in depression (3.51±1.34 vs 11.36±3.87), anxiety (2.35±1.45 vs 6.00±3.32), sleep disorder (132.90±12.26 vs 110.34±19.69) and life quality (7.58±3.37 vs 24.01±10.15) scores between the mH-Y stage Ⅱ and the stage Ⅲ patients ( t values from -10.573 to 5.439, all P<0.05), while cognitive scores did not differ significantly between the 2 PD groups ( t=1.067, P>0.05). Compared with healthy control group (1.28±0.22), the PD groups displayed a more marked decrease of SURs in the bilateral putamen and in the caudate nucleus (0.65±0.16 and 0.31±0.14; F=83.11, P<0.05), and the SURs of patients at stage Ⅱ were higher than those of the patients at stage Ⅲ ( t=9.116, P<0.05). NMSs scores of PD patients, with the exception of cognition scores, were correlated with striatal SURs ( r values from -0.647 to -0.426, all P<0.05). Regression analysis showed that total striatum SURs was the best predictor of PDSS and NMSS scores ( R2 values 0.234, 0.378, both P<0.001), while contralateral caudate nucleus SURs were best predictor of HAMD scores ( R2=0.402, P<0.001). The SURs of contralateral putamen were best variables for predicting HAMA scores ( R2=0.204, P<0.001). Conclusion:The correlation between the decreased striatal VMAT2 and a broad spectrum of NMSs in patients with PD is established, suggesting that the defect in dopamine supply may be an early abnormality promoting mechanisms leading to the development of NMSs in PD.