Patients with advanced Parkinson's disease with and without freezing of gait: a comparative analysis of vascular lesions using brain MRI

Association between white matter lesions and Parkinson's disease: an impact on Postural/Gait difficulty phenotype and cognitive performance

BACKGROUND

White matter hyperintensities (WMHs) may be observed on Magnetic Resonance Imaging (MRI) in patients with Parkinson disease with or without vascular risk factors. Whether WMHs may influence motor and non-motor aspects of Parkinson disease is a subject of debate. The aim of this study is to evaluate the impact of WMH severity on various aspects of Parkinson disease in combination to the estimation of the impact of cerebrovascular risk factors.

MATERIALS AND METHODS

We included a cohort of patients with Parkinson's disease who underwent MRI examination. The Fazekas visual rating scale was used to assess the severity and location of WMHs, and patient clinical characteristics were correlated with MRI data.

RESULTS

All vascular risk factors were associated with higher Fazekas score in both periventricular and deep white matter. Periventricular white matter hyperintensities (PWMHs) and deep white matter hyperintensities (DWMHs) were associated with lower scores in the ACE-R cognitive assessment scale (p < 0.001). Furthermore, PWMHs and DWMHs severity was associated with higher UPDRS motor score (p < 0.001), while the Postural Instability Gait Difficulty (PIGD) phenotype was correlated with higher burden of WMHs.

CONCLUSIONS

Comorbid WMHs may contribute to multi-dimension dysfunction in patients with Parkinson disease and consequently the management of vascular risk factors may be crucial to maintain motor and non-motor functions in PD.

Ethnic Variation in the Manifestation of Parkinson's Disease: A Narrative Review

The global prevalence of Parkinson's disease is increasing, yet the characteristics, risk factors and genetics of PD in Black, Asian and Hispanic populations is little understood. In this paper we review the published literature on clinical variation in the symptoms and signs of Parkinson's disease in different ethnic groups and responses to treatment. We included any study that sampled patients with Parkinson's disease from distinct ethnic backgrounds. We conclude that whilst there is little published evidence for ethnic variation in the clinical features of Parkinson's disease, there are substantial limitations and gaps in the current literature, which mean that the evidence does necessarily not fit with clinical observation. Possible explanations for expected differences in manifestation include genetic determinants, the co-existence of cerebrovascular disease and/or Alzheimer's disease pathology, healthcare inequalities and socio-cultural factors.

White Matter Hyperintensities, Dopamine Loss, and Motor Deficits in De Novo Parkinson's Disease

BACKGROUND

White matter hyperintensities, prevalent in patients with Parkinson's disease (PD), significantly affect parkinsonian motor symptoms. The objective of this study was to investigate the relationship between white matter hyperintensities and nigrostriatal dopamine depletion and their interaction or mediating effects on motor symptoms in patients with drug-naive early-stage PD.

METHODS

This cross-sectional study enrolled 501 patients with de novo PD who initially underwent [¹⁸ F] N-(3-fluoropropyl)-2β-carbonethoxy-3β-(4-iodophenyl) nortropane positron emission tomography and brain magnetic resonance imaging scans between April 2009 and September 2015 in a tertiary-care university hospital. We quantified dopamine transporter availability in each striatal subregion and assessed the severity of periventricular and lobar white matter hyperintensities using the Scheltens scale. The relationship between white matter hyperintensities, dopamine transporter availability in the posterior putamen, and Unified Parkinson's Disease Rating Scale (UPDRS) motor scores was assessed using multivariate linear regression and mediation analyses.

RESULTS

Periventricular and frontal white matter hyperintensities were generally associated with dopamine transporter availability in striatal subregions after adjusting for age at symptom onset, sex, disease duration, and vascular risk factors. There was an interaction effect between periventricular white matter hyperintensities and dopamine transporter availability in the posterior putamen for the axial motor score. The effect of white matter hyperintensities on UPDRS total score and bradykinesia subscore was indirectly mediated by dopamine transporter availability in the posterior putamen, whereas the axial sub-score was directly affected by white matter hyperintensities.

CONCLUSIONS

This study suggests that the detrimental effect of white matter hyperintensities on parkinsonian motor symptoms is more relevant and independent for axial motor impairments in the status of mildly decreased striatal dopamine transporter availability. © 2021 International Parkinson and Movement Disorder Society.

Statins are underused in recent-onset Parkinson's disease with increased vascular risk: findings from the UK Tracking Parkinson's and Oxford Parkinson's Disease Centre (OPDC) discovery cohorts

BACKGROUND

Cardiovascular disease (CVD) influences phenotypic variation in Parkinson's disease (PD), and is usually an indication for statin therapy. It is less clear whether cardiovascular risk factors influence PD phenotype, and if statins are prescribed appropriately.

OBJECTIVES

To quantify vascular risk and statin use in recent-onset PD, and examine the relationship between vascular risk, PD severity and phenotype.

METHODS

Cardiovascular risk was quantified using the QRISK2 calculator (high ≥20%, medium ≥10 and <20%, low risk <10%). Motor severity and phenotype were assessed using the Movement Disorder Society Unified PD Rating Scale (UPDRS) and cognition by the Montreal cognitive assessment.

RESULTS

In 2909 individuals with recent-onset PD, the mean age was 67.5 years (SD 9.3), 63.5% were men and the mean disease duration was 1.3 years (SD 0.9). 33.8% of cases had high vascular risk, 28.7% medium risk, and 22.3% low risk, while 15.2% of cases had established CVD. Increasing vascular risk and CVD were associated with older age (p<0.001), worse motor score (p<0.001), more cognitive impairment (p<0.001) and worse motor phenotype (p=0.021). Statins were prescribed in 37.2% with high vascular risk, 15.1% with medium vascular risk and 6.5% with low vascular risk, which compared with statin usage in 75.3% of those with CVD.

CONCLUSIONS

Over 60% of recent-onset PD patients have high or medium cardiovascular risk (meriting statin usage), which is associated with a worse motor and cognitive phenotype. Statins are underused in these patients, compared with those with vascular disease, which is a missed opportunity for preventive treatment.

TRIAL REGISTRATION NUMBER

GN11NE062, NCT02881099.

A prospective study of freezing of gait with early Parkinson disease in Chinese patients

This study investigated the risk factors for freezing of gait (FOG) in the early stage of Parkinson disease in China, using a sample of 248 patients who were followed for 3 years. Part III of the Unified Parkinson Disease Rating Scale and the modified Hoehn-Yahr grading scale were used to evaluate the severity of motor symptoms. Nonmotor symptoms were assessed using the Hamilton Anxiety Rating Scale, Hamilton Depression Rating Scale (HAMD), and Non-Motor Symptoms Scale (NMSS). The end-point was the presence of FOG at the end of follow-up; patients with FOG were classified as freezers. The risk factors for FOG were analyzed at the end of the first, second, and third years after baseline. There were 40 freezers (16.13%) 1 year later, 98 (39.52%) 2 years later, and 128 (51.61%) 3 years later. FOG 3 years later was associated with the following variables: depression (P = 0.003), older age, living in the countryside, lower education, akinetic-rigid style, lower limbs as site of onset, early use of levodopa, higher daily dose of levodopa, and not using amantadine or selegiline and dopamine receptor agonists (P < 0.001). Early use of amantadine, selegiline, and dopamine receptor agonists was negatively related to FOG (P < 0.001). Binary logistic regression found that FOG was associated with lower education (odds ratio [OR] = 0.012, P < 0.001), akinetic-rigid style (OR = 4.881, P = 0.024), not using dopamine receptor agonists (OR = 4.324, P = 0.035), cognitive disturbances (OR = 0.331, P = 0.007), and sleep disorders (OR = 2.418, P = 0.036). However, the cardiovascular domain of the NMSS (OR = 2.729, P = 0.001) was the only risk factor for FOG 1 year later. Two years later, FOG was associated with mixed style (OR = 0.189, P = 0.005), lower limbs as site of onset (OR = 4.772, P = 0.008), not using dopamine receptor agonists (OR = 0.031, P < 0.001), and the anxiety/somatic domain of the HAMD (OR = 0.596, P = 0.033). Scores at baseline, patients with Parkinson disease were more likely to experience FOG if: they were older, or from the countryside; had an akinetic-rigid style, anxiety, or higher NMSS scores; they used levodopa early or did not use amantadine or selegiline; their lower limbs were the site of onset; or they had more severe motor disability or higher HAMD scores at baseline.

Age-dependent cognitive and affective differences in Alzheimer's and Parkinson's diseases in relation to MRI findings

OBJECTIVE

To compare age-dependent changes in cognitive and affective functions related to white matter changes between patients with Alzheimer's disease (AD) and Parkinson's disease (PD).

METHODS

We retrospectively compared age-dependent cognitive and affective functions in 216 AD patients, 153 PD patients, and 103 healthy controls with cerebral white matter lesions (WMLs), periventricular hyperintensity (PVH), deep white matter hyperintensity (DWMH), micro-bleeds (MBs), and lacunar infarcts (LIs).

RESULTS

The average mini-mental state examination (MMSE) scores were 19.6±6.1 and 26.8±3.6 in AD and PD patients, respectively. Significant decreases were found in the MMSE score, Hasegawa's dementia scale-revised (HDS-R) score, frontal assessment battery score, and Abe's BPSD score (ABS) among the age-dependent AD subgroups and in the MMSE, HDS-R, Montreal cognitive assessment, geriatric depression scale, and ABS scores among the age-dependent PD subgroups; they were worse in AD patients. White matter changes were observed in >88% and >72% of patients with AD and PD, respectively. An age-dependent direct comparison of AD and PD showed significant differences in the PVH and DWMH grades, and numbers of MBs and LIs.

CONCLUSION

WML-related cognitive and affective functions worsen with age in AD and PD patients; however, the abnormalities were more frequent and stronger in AD patients.

The contribution of white matter lesions to Parkinson's disease motor and gait symptoms: a critical review of the literature

White matter lesions (WML) associated with cerebrovascular disease (CVD) may be observed on magnetic resonance imaging in Parkinson's disease (PD) patients. WML are an important factor contributing to postural, gait, and cognitive impairment in the elderly without PD and worsening the course of Alzheimer's disease (AD). Numerous articles are available on this topic. Whether WML modify and negatively influence the clinical symptoms, and course of PD is a subject of debate. The aim of this review is to examine the available literature on the contribution of WML to PD motor symptoms in relation to clinical characteristics and methods of assessing WML on MRI. After reviewing the database, we identified 19 studies reporting the relationship between WML and PD; ten studies focusing on the impact of WML on the cognitive status in PD were excluded. We analysed altogether nine studies reporting the relationship between WML and motor signs of PD. The review found association between WML severity and freezing of gait, less significant to responsiveness to dopaminergic treatment and postural instability; no negative impact on tremor and falls was observed. The impact of WML on bradykinesia and rigidity was inconsistent. Comorbid WML is associated with worsening axial motor performance, probably independently from the degree of nigrostriatal dopaminergic denervation in PD. Reducing the vascular risk factors that cause WML may be helpful in preventing the development of axial symptoms and ultimately in improving the quality of life of patients with PD. Given the lack of systematic studies, additional research in this field is needed.