Orthostatic hypotension in Parkinson disease: A 7-year prospective population-based study

Post-marketing safety of pimavanserin: a real-world pharmacovigilance study based on the FDA adverse event reporting system (FAERS)

BACKGROUND

Pimavanserin is a new non-dopamine neurotransmitter antipsychotic drug. This study aimed to conduct a post-marketing pharmacovigilance study of pimavanserin, through data mining technology using the FDA Adverse Event Reporting System (FAERS) database.

RESEARCH DESIGN AND METHODS

We analyzed adverse event reports for patients using pimavanserin. Data were classified using systematic organ classification (SOC) and preferred term (PT) of the Medical Dictionary for Regular Activities (MedDRA). Four signal algorithms [reporting odds ratio (ROR), proportional reporting ratio (PRR), multi-item gamma poisson shrinker (MGPS), and bayesian confidence propagation neural network (BCPNN)] were used to detect positive signals, and the median time-to-onset was determined.

RESULTS

Adverse drug events (ADEs) related to pimavanserin (n = 31,852) were analyzed, exhibiting an annual linear upward trend (p = 0.027). The ADEs involved 27 SOCs, but only 'Psychiatric disorders' simultaneously satisfied four algorithms. Overall, 153 PTs simultaneously satisfied four algorithms. Subgroup analysis of differences in the top 30 signal intensity PTs according to sex yielded significant results for seven PTs (p < 0.05). The median time-to-onset was 97 days, the highest proportion occurred within the first 30 days (31.79%).

CONCLUSIONS

Some new PT signals not listed in the label were identified, and some PT signals showed differences according to sex.

Orthostatic Hypotension and Risk of Mild Cognitive Impairment and Dementia in Parkinson's Disease

BACKGROUND

Orthostatic hypotension (OH) is a common condition in Parkinson's disease (PD) with a possible link to cognitive decline.

OBJECTIVE

The aim was to explore the association between OH and PD-associated mild cognitive impairment (PD-MCI) and dementia (PDD) over 9 years in a population-based incident PD cohort.

METHODS

We prospectively followed up patients from PD diagnosis with serial blood pressure measurements, clinical examinations, and neuropsychological assessments. We defined OH using (1) consensus-based criteria and (2) clinically significant OH by mean arterial pressure (MAP) in standing position ≤75 mmHg. PD-MCI and PDD were diagnosed according to acknowledged criteria. We applied generalized estimating equations models to investigate associations between OH measurements and cognitive impairment over time. Weibull accelerated failure time regression models were used to study if early OH (≤3 years of PD diagnosis) accelerates the time to incident PD-MCI and PDD.

RESULTS

Of 186 enrolled patients, consensus-based OH affected 68.8%, clinically significant OH 33.9%, PD-MCI 60.8%, and PDD 31.2%. Consensus-based OH was associated with PD-MCI (odds ratio [OR]: 2.04, 95% confidence interval: 1.44-2.90, P < 0.001), whereas clinically significant OH was associated with both PD-MCI (OR: 1.95, 1.11-3.43, P = 0.020) and PDD (OR: 3.66, 1.95-6.86, P < 0.001). Early clinically significant OH, but not early consensus-based OH, reduced time to incident PD-MCI by 54% (P = 0.021) and time to PDD by 44% (P = 0.003) independently of potential confounders, including supine hypertension and cardiovascular disease.

CONCLUSIONS

MAP in standing position emerged as a stronger predictor of cognitive decline than OH determined using consensus-based criteria. These findings have implications for both research and clinical practice.

Neuronal threshold functions: Determining symptom onset in neurological disorders

Synaptic networks determine brain function. Highly complex interconnected brain synaptic networks provide output even under fluctuating or pathological conditions. Relevant to the treatment of brain disorders, understanding the limitations of such functional networks becomes paramount. Here we use the example of Parkinson's Disease (PD) as a system disorder, with PD symptomatology emerging only when the functional reserves of neurons, and their interconnected networks, are unable to facilitate effective compensatory mechanisms. We have denoted this the "threshold theory" to account for how PD symptoms develop in sequence. In this perspective, threshold functions are delineated in a quantitative, synaptic, and cellular network context. This provides a framework to discuss the development of specific symptoms. PD includes dysfunction and degeneration in many organ systems and both peripheral and central nervous system involvement. The threshold theory accounts for and explains the reasons why parallel gradually emerging pathologies in brain and peripheral systems generate specific symptoms only when functional thresholds are crossed, like tipping points. New and mounting evidence demonstrate that PD and related neurodegenerative diseases are multisystem disorders, which transcends the traditional brain-centric paradigm. We believe that representation of threshold functions will be helpful to develop new medicines and interventions that are specific for both pre- and post-symptomatic periods of neurodegenerative disorders.

Orthostatic Hypotension: a clinical marker for the body-first subtype of patients with Parkinson's Disease

Our study aimed to investigate the clinical characteristics of PD patients stratified by OH status before and after levodopa challenge to explore the hypothesis that OH might serve as a clinical marker for the body-first subtype of PD. Supine and standing blood pressure were measured in a large cross-sectional cohort of PD patients at the OFF status before and after levodopa challenge test (LCT). Based on OH status, patients were divided into three groups: spontaneous OH (SOH), only levodopa-induced OH (LOH) and non-OH (NOH). Clinical characteristics and associated factors were compared among the groups. A total of 928 patients with a mean age of 62.4 years and average disease duration of 7.9 years were included. There were 224 (24.1%) patients with SOH, 321 (34.6%) with LOH, and 383 (41.3%) with NOH. Compared to NOH, both SOH and LOH were associated with older age, motor fluctuations, and probable rapid eye movement sleep behavior disorder (pRBD). In addition, OH was more associated with cardiovascular and digestive dysfunction, disease severity and worse quality of life. Results of the current study suggest that PD patients developed OH which is more likely to comorbid with RBD, severe autonomic dysfunction and motor fluctuations, consistent with the body-first subtype of PD.

Short term cardiovascular symptoms improvement after deep brain stimulation in patients with Parkinson's disease: a systematic review

BACKGROUND

Autonomic dysfunction is common and disabling in Parkinson's disease (PD). The effects of deep brain stimulation (DBS) on the cardiovascular system in PD remain poorly understood. We aimed to assess the effect of DBS on cardiovascular symptoms and objective measures in PD patients.

METHODS

We conducted a systematic literature search in PubMed/MEDLINE.

RESULTS

36 out of 472 studies were included, mostly involving DBS of the subthalamic nucleus, and to a lesser extent the globus pallidus pars interna and pedunculopontine nucleus. Seventeen studies evaluated the effect of DBS on patient-reported or clinician-rated cardiovascular symptoms, showing an improvement in the first year after surgery but not with longer-term follow-up. DBS has no clear direct effects on blood pressure during an orthostatic challenge (n = 10 studies). DBS has inconsistent effects on heart rate variability (n = 10 studies).

CONCLUSION

Current evidence on the impact of DBS on cardiovascular functions in PD is inconclusive. DBS may offer short-term improvement of cardiovascular symptoms in PD, particularly orthostatic hypotension, which may be attributed to dopaminergic medication reduction after surgery. There is insufficient evidence to draw conclusions on the direct effect of DBS on blood pressure and heart rate variability.

Longitudinal prevalence of neurogenic orthostatic hypotension in the idiopathic Parkinson Progression Marker Initiative (PPMI) cohort

BACKGROUND

Reported orthostatic hypotension (OH) prevalence in Parkinson's disease (PD) varies widely, with few studies evaluating specifically neurogenic-OH (nOH). The ratio of orthostatic heart rate (HR) to systolic blood pressure (SBP) change (Δ) is a valid screening method to stratify nOH/non-nOH but has had minimal epidemiologic application.

OBJECTIVE

To estimate the prevalence of nOH and non-nOH in the PPMI using the ΔHR/ΔSBP ratio and examine associations between nOH and various motor and non-motor measures.

METHODS

Longitudinal orthostatic vitals and motor and non-motor measures were extracted (baseline-month 48). Patients were consensus criteria classified as OH+/-, with ΔHR/ΔSBP sub-classification to nOH (ΔHR/ΔSBP < 0.5) or non-nOH (ratio ≥ 0.5). Prevalence was determined across visits. Independent linear mixed models tested associations between nOH/non-nOH and clinical variables.

RESULTS

Of N = 907 PD with baseline orthostatic vitals, 3.9 % and 1.8 % exhibited nOH and non-nOH, respectively. Prevalence of nOH/non-nOH increased yearly (P = 0.012, chi-square), though with modest magnitude (baseline: 5.6 % [95 % CI: 4.3-7.3 %]; month 48: 8.6 % [6.4-11.5 %]). nOH patients were older than PD with no OH and nOH was associated with greater impairment of motor and independent functioning than non-nOH/OH- groups. Cognitive function and typical OH symptoms were worse in PD + OH, generally.

CONCLUSIONS

nOH prevalence was greater than non-nOH in the PPMI early PD cohort, with modest prevalence increase over time. Our findings are consistent with prior studies of large cohorts that evaluated nOH, specifically. Those with early PD and nOH were likelier to be older and suffer from greater motor and functional impairment, but OH presence was generally associated with more cognitive impairment.

Associations of Orthostatic Hypotension and Orthostatic Intolerance with Domain-Specific Cognitive Decline in Patients with Early Parkinson Disease: An 8-Year Follow-up

OBJECTIVE

Although orthostatic hypotension (OH) and orthostatic intolerance (OI) are prevalent in patients with Parkinson disease (PD), it remains unclear how these conditions primarily affect the trajectory of decline in specific cognitive domains. This study aimed to explore the effects of OH and OI on longitudinal domain-specific cognitive changes in patients with PD.

DESIGN

An 8-year follow-up of the Parkinson Progression Markers Initiative cohort study.

SETTING AND PARTICIPANTS

A total of 403 patients with early, untreated PD and 195 matched healthy controls were included. They were classified into OH, OI, and normal groups. OH was defined according to the international consensus, and OI was defined as the presence of orthostatic symptoms without meeting the criteria for OH.

METHODS

The patients underwent detailed neuropsychological testing annually for up to 8 years of follow-up. Linear mixed effects models were used to investigate the associations between OH, OI, and longitudinal cognitive changes.

RESULTS

The prevalence of both OH and OI in patients with PD was significantly higher than that in controls (13.4% vs 7.2%, P = .002, for OH, and 29.3% vs 14.4%, P < .001, for OI). The OH group in patients with PD showed a faster decline in Letter-Number Sequencing (LNS) (β = -0.11, 95% CI -0.20 to -0.02, t = -2.44, P = .015) and Semantic Fluency Test (SFT) (β = -0.44, 95% CI -0.81 to -0.08, t = -2.42, P = .016) scores than the normal group. Similarly, the OI group showed a steeper decline in LNS (β = -0.08, 95% CI -0.14 to -0.01, t = -2.20, P = .028) and SFT (β = -0.36, 95% CI -0.63 to -0.08, t = -2.55, P = .011) scores compared to the normal group. There were no significant longitudinal changes in the other neuropsychological test scores between the groups.

CONCLUSIONS AND IMPLICATIONS

Both OH and OI may be associated with a faster decline in executive function among cognitive domains of patients with PD. These findings may highlight the potential importance of orthostatic blood pressure control in PD patients with OH and even those with orthostatic symptoms without OH.

Machine-learning model for the prediction of acute orthostatic hypotension after levodopa administration

BACKGROUND

Levodopa could induce orthostatic hypotension (OH) in Parkinson's disease (PD) patients. Accurate prediction of acute OH post levodopa (AOHPL) is important for rational drug use in PD patients. Here, we develop and validate a prediction model of AOHPL to facilitate physicians in identifying patients at higher probability of developing AOHPL.

METHODS

The study involved 497 PD inpatients who underwent a levodopa challenge test (LCT) and the supine-to-standing test (STS) four times during LCT. Patients were divided into two groups based on whether OH occurred during levodopa effectiveness (AOHPL) or not (non-AOHPL). The dataset was randomly split into training (80%) and independent test data (20%). Several models were trained and compared for discrimination between AOHPL and non-AOHPL. Final model was evaluated on independent test data. Shapley additive explanations (SHAP) values were employed to reveal how variables explain specific predictions for given observations in the independent test data.

RESULTS

We included 180 PD patients without AOHPL and 194 PD patients with AOHPL to develop and validate predictive models. Random Forest was selected as our final model as its leave-one-out cross validation performance [AUC_ROC 0.776, accuracy 73.6%, sensitivity 71.6%, specificity 75.7%] outperformed other models. The most crucial features in this predictive model were the maximal SBP drop and DBP drop of STS before medication (ΔSBP/ΔDBP). We achieved a prediction accuracy of 72% on independent test data. ΔSBP, ΔDBP, and standing mean artery pressure were the top three variables that contributed most to the predictions across all individual observations in the independent test data.

CONCLUSIONS

The validated classifier could serve as a valuable tool for clinicians, offering the probability of a patient developing AOHPL at an early stage. This supports clinical decision-making, potentially enhancing the quality of life for PD patients.

Effect of levodopa on postural blood pressure changes in Parkinson disease: a randomized crossover study

PURPOSE

We investigated the effect of levodopa on postural blood pressure changes in individuals with Parkinson disease (PD) with (PD+OH) and without neurogenic OH (PD-OH).

METHODS

We performed a prospective randomized crossover study with autonomic testing performed ON and OFF levodopa. The primary outcome was the change in systolic blood pressure (SBP) from supine to 70° tilt at 3 min (ΔSBP-3'). Secondary outcomes included indices of baroreflex function and blood pressure and heart rate during tilt.

RESULTS

We enrolled 40 individuals with PD (21 PD+OH, 19 PD-OH), mean age (SD) 73.2 years (7.9), 13 women (32.5%)). There was no difference in age, sex, disease duration, and severity between PD+OH and PD-OH. Mean difference in ΔSBP-3' ON versus OFF levodopa in the whole study population was - 3.20 mmHg [- 7.36 to 0.96] (p = 0.14). Mean difference in ΔSBP-3' was - 2.14 mmHg [- 7.55 to 3.28] (p = 0.45) in PD+OH and - 5.14 mmHg [- 11.63 to 1.35] (p = 0.14) in PD-OH. Mean difference in ΔSBP ON versus OFF levodopa was greater at 7 and 10 min (- 7.52 mmHg [- 11.89 to - 3.15], p = 0.002, and - 7.82 mmHg [- 14.02 to - 1.67], p = 0.02 respectively). Levodopa was associated with lower absolute values of blood pressure in both PD+OH and PD-OH and cardiovascular noradrenergic baroreflex impairment.

CONCLUSION

Levodopa decreases blood pressure in both PD with and without autonomic failure, but it does not cause a greater fall in blood pressure from supine to standing at 3 min. Levodopa-induced baroreflex sympathetic noradrenergic impairment may contribute to lower blood pressure. Lower standing blood pressure with levodopa may increase the risks of fall and syncope.

Advice to People with Parkinson's in My Clinic: Orthostatic Hypotension

Orthostatic hypotension (OH) is the most common manifestation of cardiovascular autonomic dysfunction in Parkinson's disease. In this viewpoint, we discuss five practical questions regarding OH in Parkinson's disease: 1) How common is the problem? 2) Why should people with Parkinson's disease and providers care about OH? 3) What are the symptoms of OH? 4) How to confirm a diagnosis of OH? And 5) How to treat OH? OH is an important non-motor symptom of Parkinson's disease for which we have available treatments to significantly mitigate morbidity and possibly positively impact the disease course.

Effects of Blood Flow Restriction Resistance Training on Autonomic and Endothelial Function in Persons with Parkinson's Disease

Background

Autonomic dysfunction precedes endothelial dysfunction in Parkinson's disease (PD) and causes blood pressure and circulation abnormalities that are highly disruptive to one's quality of life. While exercise interventions have proven helpful for motor symptoms of PD, improving associated non-motor symptoms is limited. Low-intensity resistance training with blood flow restriction (LIRT-BFR) improves autonomic dysfunction in non-PD patients and high-intensity resistance training (HIRT) is recommended for motor symptom improvements for people with PD (PwPD).

Objective

To determine the effects of LIRT-BFR and HIRT on homocysteine and autonomic and endothelial function in PwPD and to determine the hemodynamic loads during LIRT-BFR and HIRT in PwPD using a novel exercise protocol.

Methods

Thirty-eight PwPD were assigned LIRT-BFR, HIRT or to a control (CNTRL) group. The LIRT-BFR and HIRT groups exercised three days per week for four weeks. The LIRT-BFR protocol used 60% limb occlusion pressure (LOP) and performed three sets of 20 repetitions at 20% of the one-repetition maximum (1RM). The HIRT group performed three sets of eight repetitions at 80% 1RM. The CNTRL group was asked to continue their normal daily routines.

Results

LIRT-BFR significantly improved orthostatic hypotension (p = 0.026), homocysteine levels (p < 0.001), peripheral circulation (p = 0.003), supine blood pressure (p = 0.028) and heart rate variability (p = 0.041); LIRT-BFR improved homocysteine levels (p < 0.018), peripheral circulation (p = 0.005), supine blood pressure (p = 0.007) and heart rate variability (p = 0.047) more than HIRT; and hemodynamic loads for LIRT-BFR and HIRT were similar.

Conclusions

LIRT-BFR may be more effective than HIRT for autonomic and endothelial function improvements in PwPD and hemodynamic loads may be lessened in LIRT-BFR protocols using single-joint exercises with intermittent blood flow restriction. Further research is needed to determine if non-motor symptoms improve over time and if results are sustainable.

Acute effect of levodopa on orthostatic hypotension and its association with motor responsiveness in Parkinson's disease: Results of acute levodopa challenge test

OBJECTIVE

Levodopa administration can induce or worsen orthostatic hypotension (OH) in patients with Parkinson's disease (PD). Understanding of acute OH post levodopa (AOHPL) is important for rational drug use in PD patients. Primary objective of this study was to investigate the incidence of AOHPL in PD patients. The secondary objectives were a) hemodynamic character of AOHPL; b) risk factors of AOHPL; c) relationship between motor responsiveness and blood pressure (BP) change.

METHODS

490 PD inpatients underwent acute levodopa challenge test (LCT). Supine-to-standing test (STS) was done 4 times during LCT, including before levodopa and every hour post levodopa intake within 3 h. Patients were classified into two groups, AOHPL and non-AOHPL. A comprehensive set of clinical features scales was assessed, including both motor (e.g., motor response, wearing-off) and nonmotor symptoms (e.g., autonomic dysfunction, neuropsychology).

RESULTS

33.1% PD patients had OH before drug, 50.8% the same subjects had AOHPL during levodopa effectiveness. PD patients who had better response to levodopa likely to have lower standing mean artery pressure (MAP) and severer systolic BP drop after levodopa intake. BP increased when the motor performance worsened and vice versa. Beneficial response was a risk factors of AOHPL (OR = 1.624, P = 0.017).

CONCLUSIONS

AOHPL was very common in PD patients. We suggested that PD patients with risk factors should monitor hemodynamic change during LCT to avoid AOHPL following the introduction or increase of oral levodopa. The fluctuations of BP were complicated and multifactorial, likely caused by the process of PD and levodopa both.

Association between Low Blood Pressure and Subsequent Risk of Parkinson's Disease in Older Adults Aged ≥75 Years

INTRODUCTION

The association between blood pressure (BP) and incidence of Parkinson's disease (PD) in older adults remains uncertain. Therefore, this study aimed to investigate the association between BP (high or low) and PD incidence in adults aged ≥75 years.

METHODS

In this nationwide population-based cohort study, we enrolled participants aged ≥75 years without a prior PD diagnosis who had undergone health examination provided by the Korean National Health Insurance Service at least once from January 1, 2009, to December 31, 2012. The participants were followed up until December 31, 2019, or the date of their death. The Cox proportional hazards model was used to assess the risk of PD depending on systolic BP (SBP), diastolic BP (DBP), and pulse pressure.

RESULTS

Overall, 963,525 participants were enrolled in the analysis and followed up until December 31, 2019, or the date of death (40.7% male, mean age 78.5 ± 3.6 years). The mean SBP and DBP were 131.4 ± 16.7 and 77.9 ± 10.3 mm Hg, respectively. During the 10-year follow-up period, 16,414 (1.7%) newly diagnosed cases of PD were reported. A significant inverse dose-response association was found between SBP and PD incidence. In the subgroup analysis, this association was maintained for most variables, including sex, use of antihypertensive medication, comorbidities, alcohol consumption, physical activity, and body mass index, except for smoking status.

CONCLUSION

Lower SBP and DBP were associated with a higher PD incidence in older adults. These results may have substantial implications for determining the optimal BP control target in adults aged ≥75 years.

Effects of different levodopa doses on blood pressure in older patients with early and middle stages of Parkinson's disease

Objective

Levodopa is the first-line treatment for patients with Parkinson's disease (PD). However, only a few studies have focused on the tolerance of this drug in older patients with PD in the early and middle stages. Therefore, this study aimed to explore the effects of different levodopa doses on blood pressure (BP) in this subpopulation.

Methods

This cohort analysis enrolled 83 patients. The levodopa challenge test was used to evaluate drug responsiveness. After at least 12 h following anti-PD drug discontinuation, patients' BPs were measured in a lying position, after 1 min standing, and after 3 min standing, in "off state" and best "on state."

Results

BP in the 250 mg and 375 mg levodopa/benserazide groups decreased significantly in the lying and standing positions. The 3-min standing-position systolic BP was significantly influenced by the dose of levodopa/benserazide. However, no statistical change was observed in the 125 mg group. The postural-mediated systolic BP disparity was significant at 3 min in the upright position. Nineteen (incidence, 22.9%) and Twenty-five patients (incidence, 30.1%) developed complications of orthostatic hypotension (OH) in the "off state" and best "on state," respectively. Mild cognitive impairment was a risk factor for OH occurrence in the "off state." The OH occurrence in the best "on state" was associated with OH in the "off state" and urinary incontinence.

Conclusion

Our findings suggest that 250 mg or more of levodopa/benserazide could significantly reduce BP and orthostatic effect in older patients with PD in the early and middle stages. Therefore, they should routinely monitor their BP.

Trial registration number

ChiCTR2200055707.

A 3-year natural history of orthostatic blood pressure dysregulation in early Parkinson's disease

In Parkinson's disease (PD), cardiovascular dysautonomia accumulates with disease progression, but studies are lacking on the natural history behind each subtype except orthostatic hypotension. This study investigated the early natural history of orthostatic blood pressure (BP) subtypes in PD. Two hundred sixty-seven early PD patients were included. Their cardiovascular functions were assessed by head-up tilt-test and ¹²³I-metaiodobenzylguanidine scintigraphy. All patients were classified as having supine hypertension (SH), orthostatic hypertension (OHT), delayed orthostatic hypotension (dOH), or orthostatic hypotension (OH) according to consensus criteria. The patients were assigned to one of three groups: extreme BP dysregulation (BP_extreme), mild BP dysregulation (BP_mild), and no BP dysregulation (BP_none) according to their orthostatic BP subtypes. The autonomic functions of 237 patients were re-assessed after approximately 3 years. Among initially enrolled subjects, 61.8% of the patients showed orthostatic BP dysregulation: 29.6% in the BP_extreme group and 32.2% in the BP_mild group. At follow-up, the BP_extreme group increased in number, while the BP_mild group diminished. Two-thirds of the initial BP_extreme patients maintained their initial subtype at follow-up. In comparison, 40.7% of the initial BP_mild patients progressed to the BP_extreme group, and 32.4% and 14.7% of the initial BP_none group progressed to BP_extreme and BP_mild groups, respectively. Cardiac denervation was most severe in the BP_extreme group, and a linear gradient of impairment was observed across the subtypes. In conclusion, various forms of positional BP dysregulation were observed during the early disease stage. SH and OH increased with disease progression, while OHT and dOH decreased, converting primarily to SH and/or OH.

Synucleinopathies

The α-synucleinopathies include pure autonomic failure, multiple system atrophy, dementia with Lewy bodies, and Parkinson disease. The past two decades have witnessed significant advances in the diagnostic strategies and symptomatic treatment of motor and nonmotor symptoms of the synucleinopathies. This chapter provides an in-depth review of the pathophysiology, pathology, genetic, epidemiology, and clinical and laboratory autonomic features that distinguish the different synucleinopathies with an emphasis on autonomic failure as a common feature. The treatment of the different synucleinopathies is discussed along with the proposal for multidisciplinary, individualized care models that optimally address the various symptoms. There is an urgent need for clinical scientific studies addressing patients at risk of developing synucleinopathies and the investigation of disease mechanisms, biomarkers, potential disease-modifying therapies, and further advancement of symptomatic treatments for motor and nonmotor symptoms.

Caudate-anchored cognitive connectivity pursuant to orthostatic hypotension in early Parkinson's disease

¹⁸F-Florbetaben is a tracer used to evaluate the metabolic activity of and amyloid accumulation in the brain when measured in early- and late-phase, respectively. The metabolism of neural substrates could be viewed as a network and might be an important factor in cognition. Orthostatic hypotension (OH) might play an indirect moderating role in cognition, and its latent influence could modify the inherent cognitive network. This study aimed to identify changes of cognitive connectivity according to orthostatic stress in patients with early Parkinson's disease (PD). This study included 104 early PD patients who were evaluated with a head-up tilt-test and¹⁸F-Florbetaben positron emission tomography (PET). Cognition was assessed with a comprehensive neuropsychological battery that gauged attention/working memory, language, visuospatial, memory, and executive functions. PET images were analyzed visually for amyloid deposits, and early-phase images were normalized to obtain standardized uptake ratios (SUVRs) of pre-specified subregions relevant to specific cognitive domains. The caudate nucleus was referenced and paired to these pre-specified regions. The correlations between SUVRs of these regions were assessed and stratified according to presence of orthostatic hypotension. Among the patients studied, 22 (21.2%) participants had orthostatic hypotension. Nineteen patients (18.3%) were positive for amyloid-β accumulation upon visual analysis. Moderate correlations between the caudate and pre-specified subregions were observed (Spearman's rho, range [0.331-0.545]). Cognition did not differ, but the patterns of correlation were altered when the disease was stratified by presence of orthostatic stress. In conclusion, cognition in early PD responds to hemodynamic stress by adapting its neural connections between regions relevant to cognitive functions.

Association of general and abdominal adiposity with postural changes in systolic blood pressure: results from the NAKO pretest and MetScan studies

The association between anthropometric measurements and postural changes in systolic blood pressure (SBP) has not been frequently reported. This study aimed to investigate the association of body mass index (BMI) and waist circumference (WC) with postural changes in SBP in two German cross-sectional studies. Data were derived from 506 participants of the population-based German National Cohort (NAKO) pretest and from 511 participants of the convenience sample-based MetScan studies. Linear regression models were used to estimate the association between BMI and WC with the difference between standing and sitting SBP (dSBP). Odds ratios (ORs) for an increase (dSBP > 10 mmHg) or decrease (dSBP ≤ -10 mmHg) in dSBP were calculated using logistic regression. The results were pooled by meta-analysis using an inverse variance model. In pooled analysis, a 5 kg/m² higher BMI was associated with a 1.46 mmHg (95% confidence interval (CI) 0.98-1.94) higher dSBP, while a 5 cm higher WC was associated with a 0.51 mmHg (95% CI 0.32-0.69) higher dSBP. BMI or WC were associated with a higher odds of an increase in dSBP (adjusted OR, 1.71; 95% CI 1.36-2.14 per 5 kg/m² higher BMI and 1.22; 95% CI 1.05-1.40 per 5 cm higher WC) but with a reduced odds of a decline in dSBP (adjusted OR, 0.67; 95% CI 0.44-1.00 per 5 kg/m² higher BMI and 0.84; 95% CI 0.72-0.99 per 5 cm higher WC). The associations between WC and dSBP were no longer statistically significant after BMI adjustments. In conclusion, higher BMI and higher WC were associated with higher postural increases in SBP; however, WC was not related to postural changes in SBP once adjusted for BMI.

Abnormal circadian blood pressure regulation and cognitive impairment in α-synucleinopathies

Circadian blood pressure (BP) rhythm is important for the maintenance of healthy daily life, and its disruption is associated with poor outcomes. Cardiovascular autonomic failure is often observed in older populations but has a greater impact on neurodegenerative disorders such as α-synucleinopathies. These BP abnormalities include orthostatic hypotension (OH), supine hypertension (SH), and a loss of nocturnal BP fall. OH not only causes falls or syncope but is also related to cognitive impairment in α-synucleinopathies. For example, OH doubles or triples the risk for the development of cognitive impairment in Parkinson's disease (PD). The diffuse central and peripheral neuropathology of α-synuclein may contribute to both OH and cognitive impairment. Moreover, repeated cerebral hypoperfusion in OH is thought to be related to cerebrovascular and neuronal damage, which may cause cognitive impairment. SH, which often coexists with OH, is also associated with cognitive impairment through cerebrovascular damage, such as white matter lesions and cerebral microbleeds. The reverse-dipping (riser) pattern on ambulatory BP monitoring is commonly observed in PD (∼56%), regardless of disease duration and severity. It is also related to cognitive impairment and more pronounced when coexisting with OH. These abnormal circadian BP profiles may be synergistically associated with cognitive impairment and poor outcomes in α-synucleinopathies. Although evidence for aggressive control of BP dysregulation improving cognitive impairment and outcomes is limited, regular BP monitoring appears to be important for total management of α-synucleinopathies.

Impaired dynamic cerebral autoregulation: A potential mechanism of orthostatic hypotension and dementia in Parkinson’s disease

Background

Orthostatic hypotension (OH) and cognitive impairment are common non-motor symptoms of Parkinson’s disease (PD). This study aimed to investigate whether impaired dynamic cerebral autoregulation (dCA) is associated with OH and Parkinson’s disease dementia (PDD), and analyze the related risk factors in patients with PDD.

Materials and methods

We enrolled 89 patients with PD and 20 age- and sex-matched healthy controls (HCs). Cognition and different cognitive domains were assessed by the Montreal Cognitive Assessment scale. Non-invasive continuous beat-to-beat blood pressure and cerebral blood flow velocity were assessed using a servo-controlled finger plethysmograph and transcranial Doppler, respectively. dCA was examined using supine and orthostatic changes with transfer function analysis to derive the autoregulatory parameters of phase, gain, and coherence. Logistic regression analysis was performed to determine the risk factors for PDD.

Results

We found that 21 (23.6%) patients with PD had OH. These patients showed worse cognitive performance in specific cognitive tasks, such as language and orientation. The patients with OH also had poorer dCA; the very low frequency (VLF) phase in two different postures was lower than that in patients without OH as well as HCs (both P < 0.05). And the normalized gain in the VLF and low frequency (LF) in standing position was higher in PD patients with and without OH than in HCs. PDD patients also had significantly higher LF normalized gain when standing than patients without dementia (P = 0.015), indicating impaired dCA. LF normalized gain in standing (odds ratio: 3.756, 95% confidence interval: 1.241–11.367) and education were significantly associated with PDD.

Conclusion

Diminished dCA may represent a potential mechanism for OH and cognitive impairment and low educational level might be a significant factor contributing to the increased risk of PDD.

Effect of Acute Levodopa Up-Titration on Blood Pressure in Patients With Early Stage Parkinson's Disease: Results of a Levodopa Challenge Test

Objective: Levodopa up-titration is the primary therapeutic strategy as the Parkinson’s disease (PD) progresses. However, the effects of levodopa up-titration on blood pressure (BP) are inconclusive. This study aimed to investigate the effect of acute levodopa up-titration simulated by levodopa challenge test (LCT) on BP in patients with early stage PD.

Methods: We monitored BP in 52 patients with early stage PD using a standardized standing test. BP was assessed in supine position after 10 min of rest and at 1 and 3 min after standing up. BP was measured in the “off-state” and the best “on-state” during LCT in the morning at hospital. In another day, “off-state” and the best “on-state” BP was measured before and after anti-PD drug uptake in the morning at home. Demographic and clinical features of the patients were evaluated and analyzed.

Results: In the LCT, the prevalence of OH in the “off-state” and the best “on-state” was 11.5 and 13.5%, respectively. Additionally, the OH in the best “on-state” was associated with OH in the “off-state” and monoamine oxidase B inhibitor use. Although 38 (73.1%) patients experienced levodopa-induced hypotension during the LCT, no risk factors were identified. While BP reductions were observed after taking anti-PD drugs at home, no further reduction was seen during acute levodopa up-titration simulated by the LCT.

Conclusion: Our results demonstrate that acute levodopa up-titration does not exacerbate BP reduction induced by anti-PD drugs at home. BP monitoring is critical for the management of patients with PD.

Trajectory Analysis of Orthostatic Hypotension in Parkinson's Disease: Results From Parkinson's Progression Markers Initiative Cohort

Background: Orthostatic hypotension (OH) in Parkinson’s disease (PD) can lead to falls, impair quality of life, and increase mortality. A trajectory analysis of OH could be useful to predict and prevent the hypotension incidence early.

Methods: The longitudinal data of 660 patients with PD with disease duration up to 12 years were extracted from an integrated PD database. We used latent class mixed modeling (LCMM) to identify patient subgroups, demonstrating trajectories of changes in orthostatic blood pressure (BP) over time. The optimal number of subgroups was selected by several criteria including the Bayesian Information Criterion. Baseline information comparison between groups and backward stepwise logistic regression were conducted to define the distinguishing characteristics of these subgroups and to investigate the predictors for BP trajectory.

Results: We identified three trajectories for each orthostatic change of systolic blood pressure (ΔSBP), namely, Class 1 (i.e., the increasing class) consisted of 18 participants with low ΔSBP that increased continuously during the follow-up; Class 2 (i.e., the low-stable class) consisted of 610 participants with low ΔSBP that remained low throughout the follow-up; and Class 3 (i.e., the high-stable class) consisted of 32 participants with high ΔSBP at baseline that was relatively stable throughout the follow-up. Several parameters differed among subgroups, but only male sex [odds ratio (OR) = 4.687, 95% confidence interval (CI) = 1.024–21.459], lower supine diastolic blood pressure (DBP) (OR = 0.934, 95% CI = 0.876–0.996), and lower level of total protein at baseline (OR = 0.812, 95% CI = 0.700–0.941) were significant predictors of an increasing ΔSBP trajectory.

Conclusion: This study provides new information on the longitudinal development of ΔSBP in patients with PD with distinct trajectories of rapidly increasing, low-stable, and high-stable class. The parameters such as male sex, lower supine DBP, and lower total proteins help to identify the rapidly increasing class.

A pilot to assess target engagement of terazosin in Parkinson's disease

BACKGROUND

Impaired brain energy metabolism is a key feature of Parkinson's disease (PD). Terazosin (TZ) binds phosphoglycerate kinase 1 and stimulates its activity, which enhances glycolysis and increases ATP levels. Preclinical and epidemiologic data suggest that TZ may be neuroprotective in PD. We aimed to assess target engagement and safety of TZ in people with PD.

METHODS

We performed a 12-week pilot study in people with PD. Participants were randomized to receive 5 mg TZ or placebo. Participants and study personnel were blinded. We assessed TZ target engagement by measuring brain ATP with ³¹P-magnetic resonance spectroscopy (MRS) and whole blood ATP with a luminescence assay. Robust linear regression models compared changes between groups controlling for baseline brain and blood ATP levels, respectively. We also assessed clinical measures of PD and adverse events.

RESULTS

Thirteen participants were randomized. Mild dizziness/lightheadedness was more common in the TZ group, and three participants taking TZ dropped out because of dizziness and/or orthostatic hypotension. Compared to the placebo group, the TZ group had a significant increase in the ratio of βATP to inorganic phosphate in the brain. The TZ group also had a significant increase in blood ATP levels compared to the placebo group (p < 0.01).

CONCLUSIONS

This pilot study suggests that TZ may engage its target and change ATP levels in the brain and blood of people with PD. Further studies may be warranted to test the disease-modifying potential of TZ.

Identifying Parkinson's disease subtypes with motor and non-motor symptoms via model-based multi-partition clustering

Identification of Parkinson's disease subtypes may help understand underlying disease mechanisms and provide personalized management. Although clustering methods have been previously used for subtyping, they have reported generic subtypes of limited relevance in real life practice because patients do not always fit into a single category. The aim of this study was to identify new subtypes assuming that patients could be grouped differently according to certain sets of related symptoms. To this purpose, a novel model-based multi-partition clustering method was applied on data from an international, multi-center, cross-sectional study of 402 Parkinson's disease patients. Both motor and non-motor symptoms were considered. As a result, eight sets of related symptoms were identified. Each of them provided a different way to group patients: impulse control issues, overall non-motor symptoms, presence of dyskinesias and pyschosis, fatigue, axial symptoms and motor fluctuations, autonomic dysfunction, depression, and excessive sweating. Each of these groups could be seen as a subtype of the disease. Significant differences between subtypes (P< 0.01) were found in sex, age, age of onset, disease duration, Hoehn & Yahr stage, and treatment. Independent confirmation of these results could have implications for the clinical management of Parkinson's disease patients.

Neurogenic orthostatic hypotension in early stage Parkinson's disease: New insights from the first 105 patients of the BoProPark study

OBJECTIVES

The prevalence of neurogenic orthostatic hypotension (NOH, due to cardiovascular autonomic failure) at early stage of Parkinson's disease (PD) is unknown. The aims of this study are to prospectively evaluate in a cohort of PD patients recruited within 3 years from motor onset (1) cardiovascular autonomic functions by means of cardiovascular reflex tests (CRTs) and the occurrence of NOH; (2) the frequency of orthostatic symptoms with a validated questionnaire.

METHODS

We included the first 105 PD patients of the prospective "BoProPark" study. Each patient underwent CRTs (head up tilt test; Valsalva manoeuvre; deep breathing; cold face test and handgrip test) under continuous blood pressure monitoring according to standardized procedures and SCOPA-Aut questionnaire at baseline (T0) and after 16 months (T1). A group of 50 age- and sex-matched controls was used for comparison.

RESULTS

At T0 (mean age 61 ± 9 years, disease duration 19 ± 9 months) NOH was detected in 4/105 (3.8%) patients, whereas at T1 in 8/105 (7.6%). CRTs responses assessing sympathetic function were impaired at T0 in PD patients compared to controls and progressively worsened at T1. Only 1 patient at T0 and 3 at T1 with NOH reported orthostatic symptoms with low frequency, while the majority of patients reporting these symptoms did not have OH at testing.

CONCLUSIONS

Our prospective study shows that NOH is not common at early PD stage. Asymptomatic mild sympathetic impairment was observed at first evaluation and progressed with disease evolution. Secondary OH may account for the higher prevalence of OH in PD reported so far.

Cardiac sympathetic burden reflects Parkinson disease burden, regardless of high or low orthostatic blood pressure changes

Reduced uptake of ¹²³I-meta-iodobenzylguanidine (¹²³I-MIBG) and orthostatic hypotension (OH) are independently associated with worse clinical outcomes of Parkinson's disease (PD). However, their interactive influence on PD has not been studied. The role of ¹²³I-MIBG myocardial uptake, as a biomarker of PD severity, was investigated, conditional on the mediating effects of OH. A total of 227 PD patients were enrolled. Their motor and nonmotor aspects were assessed with standardized tools. Global disease burden was estimated by averaging the scaled z-scores of the assessment tools. Every patient went through ¹²³I-MIBG scan, and OH was evaluated with the head-up tilt-test. The mediating role of orthostatic blood pressure changes (ΔBP) on the association between cardiac sympathetic denervation and disease burden was investigated. Low heart-to-mediastinum (H/M) ratio with less than 1.78 was seen in 69.6% of the patient population, and 22.9% of patients had OH. Low H/M ratio was associated with OH, and these patients had worse disease burden than subjects with normal ¹²³I-MIBG uptake (global composite z-score: normal ¹²³I-MIBG vs. abnormal ¹²³I-MIBG; -0.3 ± 0.5 vs. 0.1 ± 0.7; p < 0.001). The mediation models, controlled for age and disease duration, revealed that the delayed H/M ratio and global composite score were negatively associated, irrespective of orthostatic ΔBP. Adverse relationship between cardiac sympathetic denervation and disease burden was shown without any interference from orthostatic blood pressure fluctuations. This result suggested that extracranial cardiac markers might reflect disease burden, regardless of labile blood pressure influence.

Paradoxical Cerebral Perfusion in Parkinson's Disease Patients with Orthostatic Hypotension: A Dual-Phase 18F-Florbetaben Positron Emission Tomography Study

BACKGROUND

Orthostatic hypotension (OH) may antedate Parkinson's disease (PD) or be found in early stages of the disease. OH may induce a PD brain to chronic hypotensive insults. 18F-Florbetaben (18F-FBB) tracer has a high first-pass influx rate and can be used with positron emission tomography (PET) as a surrogate marker for early- and late-phase evaluation of cerebral perfusion and cerebral amyloidosis, respectively.

OBJECTIVE

In this study, we evaluated whether 18F-FBB uptake in the early- and late-phases of PD was related to OH. This study manipulated the imaging modality to illustrate the physiology of cerebral flow with OH in PD (PD + OH).

METHODS

A group of 73 early-stage PD patients was evaluated with a head-up tilt-test and 18F-FBB PET imaging. The cognitive status was assessed by a comprehensive battery of neuropsychological tests. PET images were normalized, and both early- and late-phase standardized uptake value ratios (SUVRs) of pre-specified regions were obtained. The associations between regional SUVRs and OH and cognitive status were analyzed.

RESULTS

Twenty (27.4%) participants had OH. Thirteen (17.8%) patients were interpreted as having amyloid pathology based on regional 18F-FBB uptake. Early-phase SUVRs were higher in specific brain regions of PD + OH patients than those without OH. However, late-phase SUVRs did not differ between the groups. The early-phase SUVRs were not influenced by amyloid burden or by interaction between amyloid and orthostatic hypotension. Cognitive functions were not disparate when PD + OH patients were contrasted with non-OH patients in this study.

CONCLUSION

Cerebral blood flow was elevated in patients with early PD + OH. This finding suggests augmented cerebral perfusion in PD + OH might be a compensatory regulation in response to chronic OH.

Relationships between subendocardial perfusion impairment, arterial stiffness and orthostatic hypotension in hospitalized elderly individuals

BACKGROUND

Orthostatic hypotension is an independent risk factor for cardiovascular morbidity and mortality. Arterial stiffness has been shown to be a pathophysiological mechanism linking orthostatic hypotension and increased cardiovascular risk. This study aims to evaluate the relationship between arterial stiffness, orthostatic hypotension and subendocardial viability ratio (SEVR) and moreover to identify the main predictors of orthostatic hypotension, carotid-femoral pulse wave velocity (PWV-cf) and SEVR.

METHODS

Seventy-five patients were enrolled (mean age 82.95 ± 6.45) in Verona's AOUI Geriatric ward. They underwent blood pressure, heart rate, body weight measurements and also comorbidity, arterial stiffness (PWV-cf measured by applanation tonometry), SEVR and biochemical indexes.

RESULTS

Prevalence of orthostatic hypotension was 46.6%. Even after adjustment for age, sex, glomerular filtration rate and mean arterial pressure, SEVR values corrected for arterial oxygen and haemoglobin content were statistically lower in orthostatic hypotension patients (P = 0.05) and PWV-cf values were statistically higher in orthostatic hypotension individuals (P = 0.042). In a binary logistic regression, PWV-cf was the only significant predictor of orthostatic hypotension (odds ratio 1.123; P = 0.039; confidence interval = 1.006--1.17).In a backward logistic regression model sex, creatinine clearance and orthostatic hypotension were significant predictors of SEVR corrected for O2 content. Mean arterial pressure, creatinine clearance and orthostatic hypotension were significant predictors of PWV-cf.

CONCLUSION

This study shows that orthostatic hypotension is related to increased arterial stiffness, confirming its higher prevalence in elderly patients. Orthostatic hypotension was also associated with reduced values of corrected SEVR, showing a relevant consequence of orthostatic hypotension on subendocardial perfusion impairment.

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.

Validation of Blood Pressure Measurement Using a Smartwatch in Patients With Parkinson's Disease

Objectives: We aimed to validate the accuracy of blood pressure (BP) measurement using a smartwatch in patients with Parkinson's disease (PD).

Materials and Methods: We compared 168 pairs of BP (n = 56) measurements acquired by a smartwatch (SM-R850) with those measured by a sphygmomanometer (reference device).

Results: Differences between the smartwatch BP and reference BP measurements were compared. The mean and standard deviation of the differences systolic BP (SBP) and diastolic BP (DBP), measured by smartwatch and reference device, fulfilled both criterion 1 (0.4 ± 4.6 and 1.1 ± 4.5 mm Hg for DBP and SBP, respectively) and criterion 2 (0.2 ± 2.5 and 0.9 ± 2.4 mm Hg for DBP and SBP, respectively) of the BP validation criterion of the International Organization for Standardization.

Conclusion: BP measurement using a smartwatch with a photoplethysmography sensor is an accurate and reliable method in patients with PD.

Characteristics of the 24-h ambulatory blood pressure monitoring in patients with Parkinson's disease - the SFC BP multicentre study in China

OBJECTIVES

Cardiovascular dysautonomia can be present at early, late and even prodromal stages of Parkinson's disease. This study aimed to describe the characteristics of 24-h ambulatory blood pressure (BP) monitoring and investigate the frequency of cardiovascular dysautonomia in Parkinson's disease without an abnormal BP history.

METHODS

Parkinson's disease patients without history of abnormal BP were consecutively enrolled from three Chinese centres, on whom office BP measurement, neurological evaluations and 24-h ambulatory BP monitoring were performed.

RESULTS

Totally, 101 Parkinson's disease patients (42.6% women) with an average age of 66.6 ± 8.2 years were included in our cohort, and data analysis revealed that 26 (25.74%) patients suffered from orthostatic hypotension, among whom 18 (69.23%) were symptomatic. Patients with orthostatic hypotension compared with those without had significantly higher nocturnal SBP level, and more severe nonmotor symptoms, autonomic dysfunction and cognitive impairment. Further, 54 out of 101 (53.47%) individuals had a reverse dipping pattern in SBP and/or DBP. Reverse dippers had more cases of orthostatic hypotension (P < 0.001), and more severe nonmotor symptoms. SBP dipping ratio of less than -2.98% generated 76.9% of sensitivity, 69.3% of specificity, 46.5% of positive predictive value (PPV), 89.7% of negative predictive value (NPV) and 77.4% of accuracy, while diastolic dipping ratio of less than -1.80% generated 76.9% of sensitivity, 70.7% specificity, 47.6% of PPV, 89.8% of NPV and 77.8% of accuracy for suspecting orthostatic hypotension.

CONCLUSION

Orthostatic hypotension can occur in one-fourth Parkinson's disease patients without abnormal BP history, and reverse dipping was present in more than half of patients with Parkinson's disease. Reverse dipping pattern was helpful to suspect orthostatic hypotension.

Orthostatic hypotension in older people: considerations, diagnosis and management

Orthostatic hypotension (OH) is very common in older people and is encountered daily in emergency departments and medical admissions units. It is associated with a higher risk of falls, fractures, dementia and death, so prompt recognition and treatment are essential. In this review article, we describe the physiology of standing (orthostasis) and the pathophysiology of orthostatic hypotension. We focus particularly on aspects pertinent to older people. We review the evidence and consensus management guidelines for all aspects of management. We also tackle the challenge of concomitant orthostatic hypotension and supine hypertension, providing a treatment overview as well as practical suggestions for management. In summary, orthostatic hypotension (and associated supine hypertension) are common, dangerous and disabling, but adherence to simple structures management strategies can result in major improvements.

Cardiac 18F-Dopamine PET Distinguishes PD with Orthostatic Hypotension from Parkinsonian MSA

BACKGROUND

Parkinson's disease with orthostatic hypotension (PD + OH) can be difficult to distinguish clinically from the parkinsonian form of multiple system atrophy (MSA-P). Previous studies examined cardiac sympathetic neuroimaging to differentiate PD from MSA but without focusing specifically on PD + OH versus MSA-P, which often is the relevant differential diagnostic issue.

OBJECTIVE

To investigate the utility of cardiac sympathetic neuroimaging by 18F-dopamine positron emission tomographic (PET) scanning for separating PD + OH from MSA-P.

METHODS

Cardiac 18F-dopamine PET data were analyzed from 50 PD + OH and 68 MSA-P patients evaluated at the NIH Clinical Center from 1990 to 2020. Noradrenergic deficiency was defined by interventricular septal 18F-dopamine-derived radioactivity <6000 nCi-kg/cc-mCi in the 5' frame with mid-point 8' after initiation of 3' tracer injection.

RESULTS

18F-Dopamine PET separated the PD + OH from the MSA-P group with a sensitivity of 92% and specificity of 96%.

CONCLUSION

Cardiac 18F-dopamine PET scanning efficiently distinguishes PD + OH from MSA-P.

Delayed orthostatic hypotension in Parkinson's disease

Orthostatic hypotension (OH) is relatively common in the early stage of Parkinson's disease (PD). It is divided into delayed OH and classical OH. Classical OH in PD has been investigated widely, however, the clinical implications of delayed OH in PD have seldom been studied. The purpose of this study is to characterize delayed OH in PD. A total of 285 patients with early drug-naïve PD were enrolled and divided into three groups according to orthostatic change: no-OH, delayed OH, and classical OH. The disease severity in terms of motor, non-motor, and cognitive functions was assessed. The cortical thickness of 82 patients was analyzed with brain magnetic resonance imaging. The differences among groups and linear tendency in the order of no-OH, delayed OH, and classical OH were investigated. Seventy-seven patients were re-evaluated. Initial and follow-up evaluations were explored to discern any temporal effects of orthostasis on disease severity. Sixty-four (22.5%) patients were defined as having delayed OH and 117 (41.1%) had classical OH. Between-group comparisons revealed that classical OH had the worst outcomes in motor, non-motor, cognitive, and cortical thickness, compared to the other groups. No-OH and delayed OH did not differ significantly. Linear trends across the pre-ordered OH subtypes found that clinical parameters worsened along with the orthostatic challenge. Clinical scales deteriorated and the linear gradient was maintained during the follow-up period. This study suggests that delayed OH is a mild form of classical OH in PD. PD with delayed OH has milder disease severity and progression.

Cerebral small vessel disease may worsen motor function, cognition, and mood in Parkinson's disease

INTRODUCTION

Emerging evidence has suggested that cerebral small vessel disease (CSVD) may worsen motor function and cognition in Parkinson's disease (PD). However, the effect of CSVD on anxiety and depression in patients with PD remains unknown. This study explored the multi-dimensional effects of CSVD on PD outcomes (motor, cognition, and depression/anxiety).

METHODS

This cross-sectional study included 431 patients with PD from Beijing Tiantan Hospital from May 2016 to August 2019. CSVD imaging markers were assessed and the four-point CSVD burden score was calculated. Motor function (MDS-UPDRS III score and subscores), cognition (MMSE, MoCA), anxiety (HAMA), and depression (HAMD) were assessed in these patients. The associations of CSVD with these outcomes were analyzed using the Spearman's correlation and multivariable linear regression models.

RESULTS

Motor dysfunction, cognitive impairment, depression, and anxiety were significantly worse in patients with severe CSVD than in those with mild CSVD. Multivariable linear regression showed that CSVD burden was significantly associated with motor dysfunction (MDS-UPDRS III score and rigidity and bradykinesia subscores), impaired cognition, and high levels of depression and anxiety. A marginally significant association was observed between CSVD burden and gait/postural instability in multivariable regression analysis. Among the CSVD imaging markers, white matter hyperintensity, number of lacunes, and microbleeds were positively correlated with the severity of motor, cognitive, and emotional impairments, while the perivascular space in the basal ganglia was only correlated with cognitive impairments.

CONCLUSIONS

Comorbid CSVD may affect multiple functional domains in patients with PD. Management of cerebrovascular disease may improve PD outcomes.

Prevalence of postural hypotension in primary, community and institutional care: a systematic review and meta-analysis

BACKGROUND

Postural hypotension (PH), the reduction in blood pressure when rising from sitting or lying 0to standing, is a risk factor for falls, cognitive decline and mortality. However, it is not often tested for in primary care. PH prevalence varies according to definition, population, care setting and measurement method. The aim of this study was to determine the prevalence of PH across different care settings and disease subgroups.

METHODS

Systematic review, meta-analyses and meta-regression. We searched Medline and Embase to October 2019 for studies based in primary, community or institutional care settings reporting PH prevalence. Data and study level demographics were extracted independently by two reviewers. Pooled estimates for mean PH prevalence were compared between care settings and disease subgroups using random effects meta-analyses. Predictors of PH were explored using meta-regression. Quality assessment was undertaken using an adapted Newcastle-Ottawa Scale.

RESULTS

One thousand eight hundred sixteen studies were identified; 61 contributed to analyses. Pooled prevalences for PH using the consensus definition were 17% (95% CI, 14-20%; I2 = 99%) for 34 community cohorts, 19% (15-25%; I2 = 98%) for 23 primary care cohorts and 31% (15-50%; I2 = 0%) for 3 residential care or nursing homes cohorts (P = 0.16 between groups). By condition, prevalences were 20% (16-23%; I2 = 98%) with hypertension (20 cohorts), 21% (16-26%; I2 = 92%) with diabetes (4 cohorts), 25% (18-33%; I2 = 88%) with Parkinson's disease (7 cohorts) and 29% (25-33%, I2 = 0%) with dementia (3 cohorts), compared to 14% (12-17%, I2 = 99%) without these conditions (P < 0.01 between groups). Multivariable meta-regression modelling identified increasing age and diabetes as predictors of PH (P < 0.01, P = 0.13, respectively; R2 = 36%). PH prevalence was not affected by blood pressure measurement device (P = 0.65) or sitting or supine resting position (P = 0.24), however, when the definition of PH did not fulfil the consensus description, but fell within its parameters, prevalence was underestimated (P = 0.01) irrespective of study quality (P = 0.04).

CONCLUSIONS

PH prevalence in populations relevant to primary care is substantial and the definition of PH used is important. Our findings emphasise the importance of considering checking for PH, particularly in vulnerable populations, to enable interventions to manage it. These data should contribute to future guidelines relevant to the detection and treatment of PH.

PROSPERO

CRD42017075423.

24-Hour Levodopa-Carbidopa Intestinal Gel: Clinical Experience and Practical Recommendations

Infusion of levodopa-carbidopa intestinal gel (LCIG; also designated carbidopa-levodopa enteral suspension) for 16 hours is a standard treatment for patients with advanced Parkinson's disease, and clinical observations suggest that 24-hour LCIG infusion may further reduce symptoms. This review provides practical advice on the management of patients transitioning to 24-hour LCIG infusion. We review available clinical data for 24-hour infusion and discuss adjustments to dosing, recommendations for monitoring, and management of patient concerns, based on our clinical experience. Data from multiple studies suggest that LCIG may improve non-motor symptoms. Although few studies have examined 24-hour LCIG infusion, available data indicate that certain patients may benefit from around-the-clock treatment. Studies of 24-hour LCIG infusion are limited by small sample sizes and open-label study designs, which may hamper translation to clinical practice. In our experience, we have found that patients may benefit from 24-hour infusion when reductions in nocturnal symptoms and improvements to quality of sleep are needed. Levodopa-unresponsive freezing of gait or poorly controlled troublesome dyskinesias may also indicate a patient may benefit from 24-hour infusion. Dose adjustments, especially of the nocturnal rate, are typically necessary and, as with 16-hour infusion, patients should be monitored for autonomic dysfunction; overnight wearing off symptoms; weight changes; fluctuations in plasma levels of vitamins B₆/B₁₂, folate, and homocysteine; changes in sleep patterns; or worsening of hallucinations, delusions, and/or nightmares. Available data and our clinical experience suggest that 24-hour LCIG may be warranted among selected patients who have poorly controlled nocturnal fluctuations or early morning "off" symptoms.

Age‐related changes in blood pressure and heart rates of patients with Parkinson's disease

This study evaluated yearly changes in systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rates (HR) for patients with Parkinson's disease (PD). Data were collected for the last 10 years from medical records of 28 PD patients and 30 non‐PD patients with other neurological disorders. Age‐related changes in each group were analyzed by year using mean values of SBP, DBP, and HR obtained at their bi‐monthly visits. In results, PD patients had a gradual decrease in SBP with longer disease duration, and mean SBP significantly decreased from Year 7–11 compared to the mean values for Year 1 (p < .001 or p < .01). In non‐PD patients, mean SBP significantly increased from Year 4–11 compared to the mean values for Year 1 (p < .001 or p < .01). This is the first study to report age‐related changes of BP in individual patients with PD over 10 years.

Rivastigmine in Parkinson's Disease Dementia with Orthostatic Hypotension

OBJECTIVE

The purpose of this study was to evaluate if the cognitive benefit of rivastigmine is affected by the presence of orthostatic hypotension (OH) in patients with Parkinson's disease dementia (PDD).

METHODS

We conducted a post hoc analysis on 1,047 patients with PDD from 2 randomized controlled trials comparing rivastigmine versus placebo at week 24 (n = 501) and rivastigmine patch versus capsule at week 76 (n = 546). A drop ≥ 20 mm Hg in systolic blood pressure (SBP) or ≥ 10 in diastolic blood pressure (DBP) upon standing classified subjects as OH positive (OH+); otherwise, OH negative (OH-). The primary end point was the Alzheimer's Disease Assessment Scale - Cognitive subscale (ADAS-Cog) at week 24 and the Mattis Dementia Rating Scale (MDRS) at week 76, using intention-to-treat with retrieved dropout at week 24 and observed cases at week 76, consistent with the original analyses.

RESULTS

Overall safety was comparable between OH+ (n = 288, 27.5%) and OH- (n = 730, 69.7%), except for higher frequency of syncope (9.2%) in the OH+ placebo arm. The placebo-adjusted effect of rivastigmine on ADAS-Cog at week 24 was 5.6 ± 1.2 for OH+ and 1.9 ± 0.9 in OH- (p = 0.0165). Among subjects with OH, the MDRS change from baseline at week 76 was higher for rivastigmine capsules versus patch (10.6 ± 2.9 vs -1.5 ± 3.0, p = 0.031). The overall prevalence of OH was lower for rivastigmine than placebo at week 24 (28.3% vs 44.6%, p = 0.0476).

INTERPRETATION

The cognitive benefit from rivastigmine is larger in patients with PDD with OH, possibly mediated by a direct antihypotensive effect. ANN NEUROL 2021;89:91-98.

Orthostatic Hypotension: A Prodromal Marker of Parkinson's Disease?

BACKGROUND

Orthostatic hypotension is common in patients with Parkinson's disease (PD). However, it remains unknown whether orthostatic hypotension is a marker of prodromal PD or more advanced disease. The objectives of this study were to assess whether orthostatic hypotension is a prodromal marker of PD in the general population.

METHODS

This study was embedded in the Rotterdam Study, a large prospective population-based cohort in the Netherlands. We measured orthostatic hypotension in 6910 participants. First, we determined the relation between prevalent PD and orthostatic hypotension using logistic regression. Second, we followed PD-free participants for the occurrence of PD until 2016 and studied the association between orthostatic hypotension and the risk of PD using Cox proportional hazards models. All models were adjusted for age and sex.

RESULTS

At baseline, the mean age ± standard deviation of the study population was 69.0 ± 8.8 years, and 59.1% were women. Orthostatic hypotension was present in 1245 participants (19.8%), and 62 participants (1.0%) had PD at the time of orthostatic hypotension measurement. Participants with PD were significantly more likely to have orthostatic hypotension (odds ratio, 1.88; 95% confidence interval, 1.09-3.24). During a median (interquartile range) follow-up of 16.1 years (8.5-22.7 years), 122 participants were diagnosed with incident PD. Orthostatic hypotension at baseline was not associated with an increased risk of PD (hazard ratio, 0.97; 95% confidence interval, 0.59-1.58).

CONCLUSIONS

Our study suggests that orthostatic hypotension is common in patients with PD, but that orthostatic hypotension is not associated with an increased risk of PD and thus is not a prodromal marker of PD in the general population. © 2020 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Safety considerations when using non-ergot dopamine agonists to treat Parkinson's disease

INTRODUCTION

Nonergot dopamine agonists (NEDA) represent an excellent treatment option for Parkinson's disease (PD) patients, in both early and advanced stages of the disease. The post-marketing phase of NEDA has highlighted, though, the occurrence of important long-term adverse events.

AREAS COVERED

This review reports recent updates on NEDA adverse events, analyzing neurobiological bases and risk factors of these complications. A literature search has been performed using Medline and reviewing the bibliographies of selected articles.

EXPERT OPINION

NEDA represents a very important option in the treatment of PD. Criticisms on their use can be overcome through a better knowledge of these molecules and of the risk factors for adverse events which allow specialists to prevent the occurrence of undesired complications and consent a tailor-based approach. Abbreviations: PD: Parkinson's disease, DA: dopamine agonists, NEDA: non-ergot dopamine agonists, ICD: impulse control disorders, DAWS: dopamine agonist withdrawal syndrome, CYP: Cytochrome P, PK: pharmacokinetic, AUC: area under the curve, HRT: hormone replacement therapy, AV: atrioventricular, HF: heart failure, OH: orthostatic hypotension, RBD: REM behavior disorders, PDP: Parkinson's disease psychosis, DRT: dopamine replacement therapy, DDS: dopamine dysregulation syndrome, MMSE: Mini-Mental state examination, EDS: excessive daytime somnolence.

Orthostatic Hypotension Is Associated With Cognitive Decline in Parkinson Disease

Introduction: Cognitive impairment and orthostatic hypotension (OH) are common, disabling Parkinson disease (PD) symptoms that are strongly correlated. Whether the relationship is causative or associative remains unknown. OH may occur without classic orthostatic symptoms of cerebral hypoperfusion (i.e., lightheadedness or dizziness). Whether longitudinal differences in cognition occur between symptomatic and asymptomatic OH patients has not been explored.

Objectives: We characterized the prevalence of OH, orthostatic symptoms, and cognitive impairment among PD patients and compared cognition between patients with and without OH, and between patients with symptomatic and asymptomatic OH.

Methods: Our cross-sectional, retrospective, observational study included 226 clinically diagnosed PD patients who underwent repeated standardized evaluations. Among these, 62 had longitudinal follow-up of > 3.5 years. We compared longitudinal Montreal Cognitive Assessment (MoCA) scores between patients remaining OH-free (n = 14) and those without baseline OH that developed OH (n = 28), matched for age, sex, education, and PD duration. We also compared MoCA scores between groups with asymptomatic OH (n = 13) and symptomatic OH (n = 13) matched for the same factors.

Results: In the cross-sectional analysis, OH patients had worse cognition. In the longitudinal analysis (mean follow-up = 5.3 years), OH patients had worse cognitive decline (p = 0.027). Cognitive impairment was similar between asymptomatic and symptomatic OH patients in the cross-sectional and longitudinal analyses.

Conclusions: OH is associated with cognitive impairment in PD. Further studies are needed in larger cohorts to expand our findings and to determine whether treating OH can prevent or delay cognitive dysfunction.

The Orthostatic Hypotension Questionnaire in Swedish tested in patients with parkinsonism

BACKGROUND

Orthostatic hypotension (OH) is common among older people and in particular in conditions like Parkinson's disease (PD). The OH Questionnaire (OHQ) has been proposed as a useful patient-reported assessment tool consisting of the OH Symptom Assessment (OHSA), OH Daily Activity Scale (OHDAS), and a composite score.

AIMS OF THE STUDY

To translate the OHQ into Swedish and assess its psychometric properties.

METHODS

Following forward-backward translation, the Swedish OHQ was field-tested (n = 6) for relevance, comprehensibility, and respondent burden. It was then tested regarding scaling assumptions, targeting, reliability, and construct validity in persons with PD (n = 27) and multiple system atrophy (n = 2).

RESULTS

The Swedish OHQ was considered relevant and easy to use, with a mean completion time of 5.3 min. Scaling assumptions were acceptable for OHSA and OHDAS (corrected item-total correlations, .30-.67) but not for the total score (.12-.69). Floor/ceiling effects were ≤3.4% and reliability was >.64. Construct validity was supported by expected correlations with the SCOPA-AUT, RAND-36, and blood pressure measurements.

CONCLUSIONS

The Swedish OHQ was well received, and psychometric results suggest that the OHQ (particularly the OHDAS) is a useful tool for OH assessment in parkinsonian disorders. Further testing in larger samples is needed.

Pharmacologic treatment of orthostatic hypotension

Neurogenic orthostatic hypotension (OH) is a disabling disorder caused by impairment of the normal autonomic compensatory mechanisms that maintain upright blood pressure. Nonpharmacologic treatment is always the first step in the management of this condition, but a considerable number of patients will require pharmacologic therapies. Denervation hypersensitivity and impairment of baroreflex buffering makes these patients sensitive to small doses of pressor agents. Understanding the underlying pathophysiology can help in selecting between treatment options. In general, patients with low "sympathetic reserve", i.e., those with peripheral noradrenergic degeneration (pure autonomic failure, Parkinson's disease) and low plasma norepinephrine, tend to respond better to "norepinephrine replacers" (midodrine and droxidopa). On the other hand, patients with relatively preserved "sympathetic reserve", i.e., those with impaired central autonomic pathways but spared peripheral noradrenergic fibers (multiple system atrophy) and normal or slightly reduced plasma norepinephrine, tend to respond better to "norepinephrine enhancers" (pyridostigmine, atomoxetine, and yohimbine). There is, however, a spectrum of responses within these extremes, and treatment should be individualized. Other nonspecific treatments include fludrocortisone and octreotide. The presence of associated clinical conditions, such as supine hypertension, heart failure, postprandial hypotension, PD, MSA, and diabetes need to be considered in the pharmacologic management of these patients.

[Non-motor symptoms of Parkinson's disease from pathophysiology to early diagnosis]

Parkinson's disease is the second most common neurodegenerative disease after Alzheimer's disease. The pathophysiology of Parkinson's disease is complex and imperfectly known. Primum movens is abnormal intra-neuronal accumulation of the protein α-synuclein, leading to metabolic disturbances and neurodegeneration. This abnormal accumulation of α-synuclein is also found in dementia with Lewy bodies and multiple system atrophy, which together with Parkinson's disease form the group of α-synucleinopathies. Well known by its motor signs (bradykinesia, rest tremor, cogwheel rigidity and gait disturbance), Parkinson's disease is above all a systemic disease composed of a myriad of non-motor symptoms (constipation, sense of smell disorders, rapid eye movement sleep behaviour disorders, genitourinary disorders…). These non-motor symptoms caused by accumulation and migration of α-synuclein deposits from the gut and the olfactory bulb to the central nervous system may precede motor signs by ten years and therefore be of interest for early diagnosis. Furthermore, non-motor symptoms have a poorer impact on quality of life than motor signs themselves. Therefore, understanding, recognition and management of non-motor symptoms are crucial in management of parkinsonian patient. In this paper, we offer an update on the main non-motor symptoms of Parkinson's disease, from their pathophysiology to their screening, ending with their management.

Early autonomic and cognitive dysfunction in PD, DLB and MSA: blurring the boundaries between α-synucleinopathies

Differential diagnosis between Parkinson's disease, dementia with Lewy bodies and multiple system atrophy can be difficult, especially because in early phase they might present with overlapping clinical features. Notably, orthostatic hypotension and cognitive dysfunction are common nonmotor aspects of parkinsonian syndromes and can be both present from the earliest stages of all α-synucleinopathies, indicating a common neurobiological basis in their strong relationship. In view of the increasing awareness about the prevalence of mild cognitive dysfunction in multiple system atrophy, the relevance of autonomic dysfunction in demented parkinsonian patients, the critical role of non-motor symptoms in clustering Parkinson's disease patients and the shift to studying patients in the prodromal phase, we will discuss some intrinsic limitations of current clinical diagnostic criteria, even when applied by movement disorder specialists. In particular, we will focus on the early coexistence of autonomic and cognitive dysfunction in the setting of overt or latent parkinsonism as pitfalls in the differential diagnosis of α-synucleinopathies. As early and accurate diagnosis remains of outmost importance for counselling of patients and timely enrolment into disease-modifying clinical trials, a continuous effort of research community is ongoing to further improve the clinical diagnostic accuracy of α-synucleinopathies.