Blood pressure lability is associated with subcortical atrophy in early Parkinson's disease

Parkinson's disease patients with absence of normal dipping status were more vulnerable to cognitive impairment from the early stages

INTRODUCTION

The objective of this study was to determine the characteristics of cognitive function in Parkinson's disease (PD) patients with different dipping statuses.

METHODS

Consecutive PD patients were recruited for this study. All participants underwent 24-h ambulatory blood pressure monitor (ABPM). Corresponding scales were employed to evaluate both motor and non-motor symptoms. The subjects were categorized into reverse, reduced, normal, and extreme dipping groups based on dipping patterns. Additionally, they were divided into early and non-early stage groups according to the disease duration being more than 5 years.

RESULTS

The proportions of the four dipping groups in the early and non-early stage groups exhibited no significant differences. The Montreal Cognitive Assessment (MoCA) scores in the reverse group were significantly lower than those in the normal dipping group (16.2 ± 5.8 vs 21.1 ± 6.1,P = 0.003). The attention as well as delayed recall scores in the reverse dipping group were significant lower than those in the normal dipping group (P = 0.042; P < 0.001). The multivariate linear regression analysis revealed that absence of normal dipping was an independent risk factor (OR = -2.252; P = 0.027) for MoCA scores for PD patients.

CONCLUSIONS

PD patients with absence of normal dipping status were more vulnerable to cognitive impairment from the early stages of the disease. The 24-h ABPM is recommended for early detection of abnormal dipping status and identification of individuals at risk for cognitive decline.

Imaging the Limbic System in Parkinson's Disease-A Review of Limbic Pathology and Clinical Symptoms

The limbic system describes a complex of brain structures central for memory, learning, as well as goal directed and emotional behavior. In addition to pathological studies, recent findings using in vivo structural and functional imaging of the brain pinpoint the vulnerability of limbic structures to neurodegeneration in Parkinson's disease (PD) throughout the disease course. Accordingly, dysfunction of the limbic system is critically related to the symptom complex which characterizes PD, including neuropsychiatric, vegetative, and motor symptoms, and their heterogeneity in patients with PD. The aim of this systematic review was to put the spotlight on neuroimaging of the limbic system in PD and to give an overview of the most important structures affected by the disease, their function, disease related alterations, and corresponding clinical manifestations. PubMed was searched in order to identify the most recent studies that investigate the limbic system in PD with the help of neuroimaging methods. First, PD related neuropathological changes and corresponding clinical symptoms of each limbic system region are reviewed, and, finally, a network integration of the limbic system within the complex of PD pathology is discussed.

Blood pressure variability and structural brain changes: a systematic review

BACKGROUND

Blood pressure variability (BPV) has been linked with cognitive impairment and dementia. However, the pathophysiological mechanisms by which BPV affects cognition are unclear. This systematic review aims to assess the links between different BPV measures and white and grey matter structures.

METHODS AND RESULTS

The following databases were searched from inception through to January 2021; EMBASE, MEDLINE, EMCARE and SCOPUS. Studies that reported on the relationship between within-individual BPV (short, medium or long-term variability) or a circadian blood pressure (BP) measurement and MRI assessed brain structures were included. Overall, 20 studies met the criteria and were included, of which 11 studies looked at short-term BPV, eight articles investigated visit-to-visit BPV and one study looked at a compositional BPV measurement. Due to heterogeneity in study samples, meta-analysis was not possible. Across the included studies, associations between MRI indices and BP dipping patterns were mixed; higher long-term BPV and higher sleep systolic BPV was found to be associated with lower whole brain volume and hippocampal volume.

CONCLUSION

Increased BPV, in particular systolic long-term and systolic night-time BPV, appears to be associated with lower brain volume and hippocampal volume. This highlights the adverse effect that increased BPV has upon the brain, potentially contributing to cognitive decline, including dementia, in late-life.

Cognition and transcranial sonography in Parkinson's disease patients with or without orthostatic hypotension

BACKGROUND

Orthostatic hypotension (OH) is a common nonmotor symptom in patients with Parkinson's disease (PD), with an incidence ranging from 14% to 54%.

AIMS

This study explored changes in cognition and transcranial sonography (TCS) findings in patients with PD and OH.

METHODS

We enrolled PD patients who visited the outpatient or inpatient department from 2017 to 2020. Blood pressure was measured in different positions, and demographic data were collected. Motor and nonmotor symptoms were evaluated using standard scales. A subset of 107 patients underwent TCS.

RESULTS

We enrolled 66 PD-OH patients and 92 PD-no orthostatic hypotension (NOH) patients. There were no significant differences in gender, age, disease duration, or Hoehn and Yahr stage between groups. Binary logistic regression revealed age as an independent risk factor for OH in PD patients. There were statistically significant group differences in visuospatial and executive function and Unified Parkinson's Disease Rating Scale (UPDRS) I and II scores (p < .05). Among PD-OH patients, there was a statistically significant difference in UPDRS II and III scores between patients with or without clinical symptoms (p < .05). The substantia nigra (SN) area was significantly larger in PD-NOH patients (0.45 ± 0.18 cm2 ) than PD-OH patients (0.34 ± 0.16 cm2 ) (p < .05).

CONCLUSIONS

PD-OH patients had poorer visuospatial and executive function and lower UPDRS I and II scores compared with PD-NOH patients. Within the PD-OH group, there was no significant difference in cognition between patients with or without clinical symptoms. The difference in the SN area may indicate different subtypes of PD or a tendency to develop parkinsonism syndrome.

Extra-basal ganglia iron content and non-motor symptoms in drug-naïve, early Parkinson's disease

Background

Although iron dyshomeostasis is associated with Parkinson’s disease (PD) pathogenesis, the relationship between iron deposition and non-motor involvement in PD is not fully understood. In this study, we investigated basal ganglia and extra-basal ganglia system iron contents and their correlation with non-motor symptoms in drug-naïve, early-stage PD patients.

Methods

We enrolled 14 drug-naïve, early-stage PD patients and 12 age/sex-matched normal controls. All participants underwent brain magnetic resonance imaging to obtain the effective transverse relaxation rate (R2*) and quantitative susceptibility mapping (QSM). Deep brain structures, including the nucleus accumbens, caudate nucleus, putamen, globus pallidus, thalamus, hippocampus, and amygdala, were delineated using the FSL-FIRST; the substantia nigra, red nucleus, and dentate nucleus were segmented manually. Inter-group differences in R2* and QSM values, as well as their association with clinical parameters of PD, were investigated.

Results

Substantia nigra and putamen R2* values were significantly higher in PD patients than in normal controls, despite no significant difference in QSM values. Regarding the non-motor symptom scales, PD sleep scale score negatively correlated with R2* values in the red nucleus and right amygdala, Scales for Outcomes in Parkinson’s disease-Autonomic scores were positively correlated with R2* values in the right amygdala and left hippocampus, and cardiovascular sub-score of Non-Motor Symptoms Scale for PD was positively associated with the QSM value in the left hippocampus.

Conclusion

In this study, iron content in the extra-basal ganglia system was significantly correlated with non-motor symptoms, especially sleep problems and dysautonomia, even in early-stage PD.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10072-021-05223-0.

Blood Pressure Patterns in Patients with Parkinson's Disease: A Systematic Review

(1) Background: Cardiovascular autonomic dysfunction is a non-motor feature in Parkinson’s disease with negative impact on functionality and life expectancy, prompting early detection and proper management. We aimed to describe the blood pressure patterns reported in patients with Parkinson’s disease, as measured by 24-h ambulatory blood pressure monitoring. (2) Methods: We conducted a systematic search on the PubMed database. Studies enrolling patients with Parkinson’s disease undergoing 24-h ambulatory blood pressure monitoring were included. Data regarding study population, Parkinson’s disease course, vasoactive drugs, blood pressure profiles, and measurements were recorded. (3) Results: The search identified 172 studies. Forty studies eventually fulfilled the inclusion criteria, with 3090 patients enrolled. Abnormal blood pressure profiles were commonly encountered: high blood pressure in 38.13% of patients (938/2460), orthostatic hypotension in 38.68% (941/2433), supine hypertension in 27.76% (445/1603) and nocturnal hypertension in 38.91% (737/1894). Dipping status was also altered often, 40.46% of patients (477/1179) being reverse dippers and 35.67% (310/869) reduced dippers. All these patterns were correlated with negative clinical and imaging outcomes. (4) Conclusion: Patients with Parkinson’s disease have significantly altered blood pressure patterns that carry a negative prognosis. Ambulatory blood pressure monitoring should be validated as a biomarker of PD-associated cardiovascular dysautonomia and a tool for assisting therapeutic interventions.