SCOPA-AUT scale in different parkinsonisms and its correlation with (123) I-MIBG cardiac scintigraphy

Association between autonomic dysfunction with motor and non-motor symptoms in patients with Parkinson's disease

To investigate the association between autonomic dysfunction (AutD) and motor as well as non-motor symptoms (NMS) in patients with Parkinson's disease (PD). Fifty-three PD patients were divided into two groups based on the number of domains affected by AutD: a multi-domain AutD group (AutD-M) and a single-domain AutD group (AutD-S), as evaluated using the Scale for Outcomes in Parkinson's disease-Autonomic (SCOPA-AUT), which assesses autonomic symptoms, one of the NMS. A comprehensive comparison was conducted between the two groups, including clinical measures such as clinical scales, quantitative evaluations of motor function and exercise capacity. Spearman correlation analysis was employed to investigate the relationship between AutD severity and PD symptoms. Additionally, we performed multiple linear regression model analysis to determine whether associations between SCOPA-AUT scores and clinical assessments remained significant after adjusting for Hoehn and Yahr stage, sex, and age. PD patients in the AutD-M group exhibited significantly more severe NMS and motor symptoms compared to those in the AutD-S group. In correlation analysis, SCOPA-AUT scores showed significant correlations with multiple clinical symptoms, such as most of the NMS, 10-MWT and CPET parameters. Furthermore, regression analysis also revealed that more pronounced fatigue, anxiety, depressive symptoms, worse walking speed and impaired exercise capacity were associated with higher SCOPA-AUT scores. The presence of AutD is correlated with emotional disturbances, decreased exercise endurance, and impaired gait function in patients with PD. Early management of AutD may prove beneficial in alleviating some NMS and motor symptoms in PD.

Cardiac 123I-Metaiodobenzylguanidine (MIBG) Scintigraphy in Parkinson's Disease: A Comprehensive Review

Cardiac sympathetic denervation, as documented on 123I-metaiodobenzylguanidine (MIBG) myocardial scintigraphy, is relatively sensitive and specific for distinguishing Parkinson's disease (PD) from other neurodegenerative causes of parkinsonism. The present study aims to comprehensively review the literature regarding the use of cardiac MIBG in PD. MIBG is an analog to norepinephrine. They share the same uptake, storage, and release mechanisms. An abnormal result in the cardiac MIBG uptake in individuals with parkinsonism can be an additional criterion for diagnosing PD. However, a normal result of cardiac MIBG in individuals with suspicious parkinsonian syndrome does not exclude the diagnosis of PD. The findings of cardiac MIBG studies contributed to elucidating the pathophysiology of PD. We investigated the sensitivity and specificity of cardiac MIBG scintigraphy in PD. A total of 54 studies with 3114 individuals diagnosed with PD were included. The data were described as means with a Hoehn and Yahr stage of 2.5 and early and delayed registration H/M ratios of 1.70 and 1.51, respectively. The mean cutoff for the early and delayed phases were 1.89 and 1.86. The sensitivity for the early and delayed phases was 0.81 and 0.83, respectively. The specificity for the early and delayed phases were 0.86 and 0.80, respectively.

Reduced 123I-MIBG uptake in the parotid and submandibular glands in patients with Parkinson's disease identified using a quantitative semi-automatic method

OBJECTIVES

To analyze 123I-metaiodobenzylguanidine (MIBG) uptake in the parotid and submandibular glands in patients with Parkinson's disease (PD) in comparison with controls, and to compare MIBG uptake between those glands and the myocardium. Furthermore, we aimed to identify the relationships between clinical features and MIBG uptake.

METHODS

We recruited 77 patients with PD and 21 age-matched controls. We assessed MIBG scintigraphy in the major salivary glands and myocardium. We calculated the MIBG uptake ratio in the parotid glands/mediastinum (P/M), submandibular glands/mediastinum (S/M), and heart/mediastinum (H/M) using a quantitative semi-automatic method. We investigated the correlations between MIBG uptake and clinical features.

RESULTS

The P/M and H/M ratios in the early and delayed phases were significantly reduced in PD patients compared to controls, while the delayed phase S/M ratio was reduced in PD patients compared to controls. The P/M ratio correlated with the S/M ratio, while neither the P/M nor S/M ratio correlated with the H/M ratio. Between PD patients and controls, sensitivity and specificity were 54.8% and 59.1% for the delayed phase P/M ratio, while sensitivity and specificity were 59.5% and 61.0% for the delayed phase S/M ratio, respectively. Furthermore, sensitivity and specificity for the delayed phase H/M ratio were 85.7% and 79.2, respectively.

CONCLUSION

MIBG uptake in the parotid and submandibular glands was reduced in patients with PD. Furthermore, sympathetic denervation in the major salivary glands and myocardium might progress independently. Our findings suggest a new aspect of the pathological distribution of PD.

Autonomic dysfunction in progressive supranuclear palsy

BACKGROUND

The degree of involvement of the autonomic nervous system in progressive supranuclear palsy (PSP) has been investigated in several studies, often providing conflicting results. There is a need for a better characterization of autonomic dysfunction in PSP, to enhance our understanding of this highly disabling neurodegenerative disease including patients' needs and possibly be of value for clinicians in the differential diagnosis among Parkinsonian syndromes.

METHODS

We applied a systematic methodology to review existing literature on Pubmed regarding autonomic nervous system involvement in PSP.

RESULTS

PSP reported quite frequently symptoms suggestive of autonomic dysfunction in all domains. Cardiovascular autonomic testing showed in some cases a certain degree of impairment (never severe). There was some evidence suggesting bladder dysfunction particularly in the storage phase. Dysphagia and constipation were the most common gastrointestinal symptoms. Instrumental tests seemed to confirm sudomotor and pupillomotor disturbances.

CONCLUSIONS

PSP patients frequently reported visceral symptoms, however objective testing showed that not always these reflected actual autonomic impairment. Further studies are needed to better delineate autonomic profile and its prognostic role in PSP.

Differential impact of individual autonomic domains on clinical outcomes in Parkinson's disease

INTRODUCTION

While autonomic failure is a well-known prognostic factor for more aggressive disease progression in Parkinson's disease (PD), with a three- to sevenfold higher risk of dementia and death within 10 years after the diagnosis, the individual impact of cardiovascular, gastrointestinal, urogenital, thermoregulatory, and pupillomotor autonomic domains on PD clinical outcomes remains unclear.

OBJECTIVES

We sought to determine the 5-year risk of developing dementia, falls, postural instability, dysarthria, and dysphagia in PD patients with and without autonomic impairment at baseline and to assess the joint and individual association of each autonomic domain on these key functional outcomes. In addition, we aimed to determine the impact of each autonomic domain on activities of daily living (ADLs) and health-related quality of life (HRQoL).

METHODS

We enrolled 65 consecutive PD patients in a 5-year cohort study involving standardized evaluations of autonomic symptoms, orthostatic hypotension, and motor and non-motor features, including cognitive function. Associations were estimated as odds ratio and adjusted for PD duration, age, and baseline motor impairment.

RESULTS

Cardiovascular dysautonomia was associated with a sevenfold higher risk of developing dementia (95%CI: 1.154-50.436; p = 0.035) and a fivefold higher risk of falls (95%CI: 1.099-18.949; p = 0.039), as well as significantly higher impairment in ADLs (p = 0.042) and HRQoL (p = 0.031). No relevant associations were found between the other autonomic domains and these outcomes.

CONCLUSIONS

Cardiovascular dysautonomia, but not other domains, showed an association with worse 5-year clinical outcomes in PD. Our data suggest a specific role for cardiovascular autonomic dysregulation in the pathogenic mechanisms of PD progression.

Cardiac sympathetic innervation in Parkinson's disease versus multiple system atrophy

Purpose

The aims of this study were to evaluate the diagnostic accuracy of the dual imaging method combining cardiac iodine-¹²³-metaiodobenzylguanidine single-photon emission computed tomography combined with low-dose chest computed tomography compared to routine cardiac scintigraphy, and assess regional differences in tracer distribution and the relationships between imaging and autonomic function in Parkinson’s disease and multiple system atrophy.

Methods

A prospective study including 19 Parkinson’s disease and 12 multiple system atrophy patients was performed. Patients underwent clinical evaluation, iodine-¹²³-metaiodobenzylguanidine single-photon emission computed tomography combined with chest computed tomography, planar scintigraphy, and cardiovascular autonomic function tests.

Results

Co-registration of single-photon emission computed tomography and chest computed tomography resulted in three groups with distinct patterns of tracer uptake: homogeneous, non-homogeneously reduced and absent. There was a significant difference in group allocation among patients with multiple system atrophy and Parkinson’s disease (p = 0.001). Most multiple system atrophy patients showed homogeneous uptake, and the majority of Parkinson’s disease patients showed absent cardiac tracer uptake. We identified a pattern of heterogeneous cardiac tracer uptake in both diseases with reductions in the apex and the lateral myocardial wall. Sympathetic dysfunction reflected by a missing blood pressure overshoot during Valsalva manoeuvre correlated with cardiac tracer distribution in Parkinson’s disease patients (p < 0.001).

Conclusions

The diagnostic accuracy of the dual imaging method and routine cardiac scintigraphy were similar. Anatomical tracer allocation provided by the dual imaging method of cardiac iodine-¹²³-metaiodobenzylguanidine single-photon emission computed tomography and chest computed tomography identified a heterogeneous subgroup of Parkinson’s disease and multiple system atrophy patients with reduced cardiac tracer uptake in the apex and the lateral wall. Sympathetic dysfunction correlated with cardiac imaging in 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.

Activities of daily living as a longitudinal moderator of the effect of autonomic dysfunction on anxiety and depression of Parkinson's patients

BACKGROUND

There is no clear time point for the onset of depression and anxiety in Parkinson's disease (PD), and their atypical physical symptoms often overlap with other nonmotor symptoms. Autonomic dysfunction usually appears earlier than motor symptoms, seriously impairing activities of daily living (ADL), even quality of life. Whether autonomic dysfunction can affect depression and anxiety in PD patients through ADL is still unclear.

METHODS

We conducted three progressive autoregressive mediation models to evaluate whether ADL may mediate the association between autonomic symptom burden, where the mediation chain with autonomic function as an independent variable, ADL as a mediating variable, and anxiety and depression as dependent variables. The ADL of PD patients were measured by the Scales for Outcomes in Parkinson's disease-Autonomic (SCOPA-AUT) and Modified Schwab and England ADL scale, respectively, and the status of depression and anxiety were measured by the Geriatric Depression Scale (GDS) and State-Trait Anxiety Inventory (STAI).

RESULTS

There were 338 PD patients, including 220 males and 118 females. Demographic information, including age, gender, and education level, were not correlated with the depression and anxiety. Model III had the smallest AIC (AIC = 12,669.89), and the cross-lagged relations were not statistically significant, so we selected Model II as the optimal model. In Model II, longitudinal autoregressive mediated effect and longitudinal mediated effect of autonomic dysfunction affecting anxiety and depression through ADL were not statistically significant, suggesting longitudinal changes of autonomic dysfunction were independent of anxiety and depression through ADL. Contemporaneous mediated effects of autonomic dysfunction affecting anxiety and depression through ADL were statistically significant, suggesting contemporaneous autonomic dysfunction may contribute to anxiety and depression through ADL.

CONCLUSIONS

Targeted prevention and intervention measures for autonomic dysfunction and ADL should be taken to preserve and improve self-perceived life satisfaction in the clinical practice and preventive health care of PD.

Relationship between the washout rate of I-123 MIBG scans and autonomic function in Parkinson's disease

Purpose

We have evaluated the clinical significance of the washout rate (WR) on I-123 MIBG scans through the analysis of the relationship between the I-123 MIBG scans and autonomic status in patients with Parkinson’s disease (PD).

Materials and methods

Sixty patients with clinical PD who had decreased HMR were enrolled. An autonomic symptom was evaluated using a head-up tilt test and the Composite Autonomic Severity Score (CASS). An I-123 MIBG scan and F-18 FP-CIT positron emission tomography (PET) were performed. All of the patients were classified into three groups according to the WR. The differences in patient characteristics and the imaging parameters among the three groups were evaluated, and a correlation analysis was also performed.

Results

The frequency of orthostatic hypotension was significantly different among the three groups. The difference in systolic pressure (dSysPr) and the difference in diastolic pressure (dDiaPr) of group 3 was significantly larger than those of groups 1 and 2. From the correlation analysis, it can be seen that age, Hoehn and Yahr (H&Y) stage, dSysPr, and dDiaPr had a weak positive correlation with the WR. The total CASS score was significantly higher in group 3 compared with groups 1 and 2. The WR had a moderate positive correlation with the cardiosympathetic score and the total CASS score.

Conclusion

The WR is related to autonomic dysfunction. An I-123 MIBG cardiac scan is considered to be a good method to evaluate not only the differential diagnosis of Parkinson's disease but also the degree of autonomic dysfunction.

Clinical autonomic dysfunction in narcolepsy type 1

Study Objectives

(1) To compare the presence of autonomic symptoms using the validated SCOPA-AUT questionnaire in untreated patients with narcolepsy type 1 (NT1) to healthy controls, (2) to study the determinants of a high total SCOPA-AUT score in NT1, and (3) to evaluate the effect of drug intake on SCOPA-AUT results in NT1.

Methods

The SCOPA-AUT questionnaire that evaluates gastrointestinal, urinary, cardiovascular, thermoregulatory, pupillomotor, and sexual dysfunction was completed by 92 consecutive drug-free adult NT1 patients (59 men, 39.1 ± 15.6 years old) and 109 healthy controls (63 men, 42.6 ± 18.2 years old). A subgroup of 59 NT1 patients completed the questionnaire a second time, under medication (delay between two evaluations: 1.28 ± 1.14 years).

Results

Compared to controls, NT1 patients were more frequently obese, had more dyslipidemia, with no difference for age and gender. The SCOPA-AUT score of NT1 was higher than in controls in crude and adjusted models. Patients experienced more problems than controls in all subdomains. A higher score in NT1 was associated with older age, longer disease duration, altered quality of life and more depressive symptoms, but not with orexin levels and disease severity. Among patients evaluated twice, the SCOPA-AUT score total did not differ according to treatment status, neither did each subdomain.

Conclusion

We captured a frequent and large spectrum of clinical autonomic dysfunction in NT1, with impairment in all SCOPA-AUT domains, without key impact of medication intake. This assessment may allow physicians to screen and treat various symptoms, often not spontaneously reported but associated with poor quality of life.

Nocturnal Hypertension in Multiple System Atrophy May Cause Posterior Reversible Encephalopathy Syndrome

Nocturnal hypertension (NH) is a symptom of cardiovascular dysautonomia in multiple system atrophy (MSA); however, care and medication are often insufficient. We herein report a patient with MSA who showed posterior reversible encephalopathy syndrome (PRES) caused by hypertension during sleep. He presented clinically with total blindness; T2-weighted magnetic resonance imaging showed high signal intensities in the bilateral subcortical occipital-temporal lobes. His PRES was completely reversed by blood pressure control. NH may contribute to the development of PRES. The appropriate assessment and management of hemodynamic changes in MSA, including NH, is necessary to prevent severe complications such as PRES.

Imaging the Autonomic Nervous System in Parkinson's Disease

PURPOSE OF REVIEW

Patients with Parkinson's disease (PD) often display gastrointestinal and genitourinary autonomic symptoms years or even decades prior to diagnosis. These symptoms are thought to be caused in part by pathological α-synuclein inclusions in the peripheral autonomic and enteric nervous systems. It has been proposed that the initial α-synuclein aggregation may in some PD patients originate in peripheral nerve terminals and then spread centripetally to the spinal cord and brainstem. In vivo imaging methods can directly quantify the degeneration of the autonomic nervous system as well as the functional consequences such as perturbed motility. Here, we review the methodological principles of these imaging techniques and the major findings in patients with PD and atypical parkinsonism.

RECENT FINDINGS

Loss of sympathetic and parasympathetic nerve terminals in PD can be visualized using radiotracer imaging, including ¹²³I-MIBG scintigraphy, and ¹⁸F-dopamine and ¹¹C-donepezil PET. Recently, ultrasonographical studies disclosed reduced diameter of the vagal nerves in PD patients. Radiological and radioisotope techniques have demonstrated dysmotility and prolonged transit time throughout all subdivisions of the gastrointestinal tract in PD. The prevalence of objective dysfunction as measured with these imaging methods is often considerably higher compared to the prevalence of subjective symptoms experienced by the patients. Degeneration of the autonomic nervous system may play a key role in the pathogenesis of PD. In vivo imaging techniques provide powerful and noninvasive tools to quantify the degree and extent of this degeneration and its functional consequences.

Role of peripheral vascular resistance as an indicator of cardiovascular abnormalities in patients with Parkinson's disease

The aim of this study was to evaluate cardiovascular autonomic modulation in response to an orthostatic stress in healthy subjects and Parkinson's disease (PD). The study included 47 controls and 56 PD patients divided into groups (vasoconstrictor PD, vasodilator PD, control) according to vasodilation/vasoconstriction response during 70° head up tilt test. Using impedance cardiography (ICG) and electrocardiography (ECG) we measured stroke volume, cardiac output, left ventricular work index, left ventricular ejection time, acceleration index, index of contractility, Heather index, thoracic fluid content, total peripheral resistance, total arterial compliance. We also analyzed heart rate variability (HRV), using spectral analysis and continuous blood pressure (contBP). At rest, the vasodilator PD group showed significantly higher values of total peripheral resistance and lower values of stroke volume and cardiac output, compared to the vasoconstrictor PD and the control groups. A post-tilt drop in ∆ (change rest - tilt) systolic blood pressure, ∆mean blood pressure, ∆total peripheral resistance and ∆Heather index, and a significantly lower increase in ∆diastolic blood pressure was observed in subjects from the vasodilator PD group compared to the vasoconstrictor PD and the control groups. No statistically significant differences were observed for HRV parameters between the vasoconstrictor and vasodilator PD groups, P > .05. Longer duration and higher disease stage of PD correlated with a reduction in post-tilt systolic blood pressure changes in vasodilator group. Positive inotropy of the cardiac muscle represents a significant factor preventing orthostatic hypotension in PD subjects with a concurrent drop in peripheral vascular resistance during orthostatic stress.

Autonomic Dysfunction in Early Parkinson's Disease: Results from the United Kingdom Tracking Parkinson's Study

BACKGROUND

Autonomic dysfunction is common in the later stages of Parkinson's disease (PD), but less is known about its presence and severity in early disease.

OBJECTIVE

To analyze features of autonomic dysfunction in recent onset PD cases, and their relationship to motor severity, medication use, other nonmotor symptoms (NMS), and quality-of-life scores.

METHODS

Detailed patient-reported symptoms of autonomic dysfunction were assessed in a multicenter cohort study in PD cases that had been diagnosed within the preceding 3.5 years.

RESULTS

There were 1746 patients (1132 males, 65.2%), mean age 67.6 years (SD 9.3), mean disease duration 1.3 years (SD 0.9), mean Movement Disorder Society Unified Parkinson's Disease Rating Scale motor score 22.5 (SD 12.1). Orthostatic symptoms were reported by 39.6%, male erectile dysfunction by 56.1%, and female anorgasmia by 57.4%. Sialorrhea was an issue in 51.4% of patients, constipation in 43.6%, and dysphagia in 20.1%. Autonomic features increased with higher modified Hoehn and Yahr stages (P < 0.001). The severity of autonomic dysfunction was associated with the postural instability gait difficulty motor phenotype [β-coefficient 1.7, 95% confidence interval (CI) 0.7, 2.6, P < 0.001], depression (β-coefficient 4.1, CI 3.0, 5.2, P < 0.001), and excess daytime sleepiness (β-coefficient 3.1, CI 1.9, 4.2, P < 0.001). Dopamine agonists were the only drug class associated with greater autonomic dysfunction (P = 0.019). The severity of autonomic dysfunction strongly correlated with the presence of other NMS (ρ = 0.717, P < 0.001), and with poorer quality-of-life scores (ρ = 0.483, P < 0.001).

CONCLUSIONS

Autonomic dysfunction is common in early PD. Autonomic dysfunction correlates with the presence of other NMS, and with worse quality of life.

Neurogenic orthostatic hypotension and supine hypertension in Parkinson's disease and related synucleinopathies: prioritisation of treatment targets

Neurogenic orthostatic hypotension and supine hypertension are common manifestations of cardiovascular dysautonomia in Parkinson's disease and related synucleinopathies. Because these disorders are haemodynamic opposites, improvement in one might be achieved at the expense of worsening of the other. Thus, management decisions necessitate assessment of the individual risks for patients with coexistent neurogenic orthostatic hypotension and supine hypertension. Whereas neurogenic orthostatic hypotension poses risks for falls and can be associated with cognitive impairment in the short term, chronic supine hypertension can be associated with stroke and myocardial infarction in the long term. Because few clinical trial data exist for outcomes in patients with coexistent neurogenic orthostatic hypotension and supine hypertension, clinicians need to balance, on the basis of comorbidities and disease staging, the potential immediate benefits of treatment for neurogenic orthostatic hypotension and the long-term risks of supine hypertension treatment in each patient. Future research needs to focus on ascertaining a safe degree of supine hypertension when treating neurogenic orthostatic hypotension; the effectiveness of nocturnal antihypertensive therapy in patients with coexistent neurogenic orthostatic hypotension and supine hypertension; and the prevalence, scope, and therapeutic requirements for managing neurogenic orthostatic hypotension that manifests with falls or cognitive impairment, but without postural lightheadedness or near syncope.

Imaging Parkinson's disease below the neck

Parkinson's disease is a systemic disorder with widespread and early α-synuclein pathology in the autonomic and enteric nervous systems, which is present throughout the gastrointestinal canal prior to diagnosis. Gastrointestinal and genitourinary autonomic symptoms often predate clinical diagnosis by several years. It has been hypothesized that progressive α-synuclein aggregation is initiated in hyperbranched, non-myelinated neuron terminals, and may subsequently spread via retrograde axonal transport. This would explain why autonomic nerves are so prone to formation of α-synuclein pathology. However, the hypothesis remains unproven and in vivo imaging methods of peripheral organs may be essential to study this important research field. The loss of sympathetic and parasympathetic nerve terminal function in Parkinson's disease has been demonstrated using radiotracers such as 123I-meta-iodobenzylguanidin, 18F-dopamine, and 11C-donepezil. Other radiotracer and radiological imaging methods have shown highly prevalent dysfunction of pharyngeal and esophageal motility, gastric emptying, colonic transit time, and anorectal function. Here, we summarize the methodology and main findings of radio-isotope and radiological modalities for imaging peripheral pathology in Parkinson's disease.

Diagnosing and treating neurogenic orthostatic hypotension in primary care

In response to a change in posture from supine or sitting to standing, autonomic reflexes normally maintain blood pressure (BP) by selective increases in arteriovenous resistance and by increased cardiac output, ensuring continued perfusion of the central nervous system. In neurogenic orthostatic hypotension (NOH), inadequate vasoconstriction and cardiac output cause BP to drop excessively, resulting in inadequate perfusion, with predictable symptoms such as dizziness, lightheadedness and falls. The condition may represent a central failure of baroreceptor signals to modulate cardiovascular function, a peripheral failure of norepinephrine release from cardiovascular sympathetic nerve endings, or both. Symptomatic patients may benefit from both non-pharmacologic and pharmacologic interventions. Among the latter, two pressor agents have been approved by the US Food and Drug Administration: the sympathomimetic prodrug midodrine, approved in 1996 for symptomatic orthostatic hypotension, and the norepinephrine prodrug droxidopa, approved in 2014, which is indicated for the treatment of symptomatic neurogenic orthostatic hypotension caused by primary autonomic failure (Parkinson's disease, multiple system atrophy and pure autonomic failure). A wide variety of off-label options also have been described (e.g. the synthetic mineralocorticoid fludrocortisone). Because pressor agents may promote supine hypertension, NOH management requires monitoring of supine BP and also lifestyle measures to minimize supine BP increases (e.g. head-of-bed elevation). However, NOH has been associated with cognitive impairment and increases a patient's risk of syncope and falls, with the potential for serious consequences. Hence, concerns about supine hypertension - for which the long-term prognosis in patients with NOH is yet to be established - must sometimes be balanced by the need to address a patient's immediate risks.

Cardiocirculatory manifestations in Parkinson's disease patients without orthostatic hypotension

The objective of this study was to characterize cardiac sympathetic denervation in Parkinson's disease (PD) patients without neurogenic orthostatic hypotension (NOH), both in terms of hemodynamics and in its relation with vascular denervation. We studied 20 PD patients without NOH. We analyzed the heart rate and blood pressure variability during various physical maneuvers. The following parameters were calculated: expiratory-inspiratory ratio, stroke volume, cardiac output, cardiac index, left ventricular ejection time, left ventricular work index, thoracic fluid content, total peripheral resistance and baroreflex sensitivity (BRS). We also measured direct and spectral derivatives of cardiac (cardiovagal) parasympathetic function. Myocardial I-123 metaiodobenzylguanidine (MIBG) scintigraphy was performed and early and late heart/mediastinum uptake ratios were analyzed. We observed that the late heart/mediastinum uptake ratio was 1.33±0.21. This parameter was correlated with years since diagnosis (correlation coefficient:-0.485; P=0.05), Unified Parkinson's Disease Rating Scale (UPDRS) III score (cc:-0.564; P=0.02) and pressure recovery time in the Valsalva maneuver (cc: 0.61; P<0.001). At rest, it was correlated with BRS (cc:0.75; P=0.003) and low-frequency diastolic blood pressure (LFDBP; cc: 0.58;P=0.017). We found no correlations with any of the cardiography impedance variables. In linear regression models, the variable that best correlated with MIBG results was LFDBP. Our results support that in absence of NOH the degree of denervation of the heart does not produce any effect on its inotropic function. Moreover, BRS and LFDBP can be used as an indirect measure of cardiac sympathetic denervation at rest.

Nocturnal hypertension and dysautonomia in patients with Parkinson's disease: are they related?

Orthostatic hypotension and supine hypertension frequently coexist in Parkinson's disease (PD) patients, leading to visceral damage and increased mortality rates. The aim of this paper is to analyze the frequency and association of both conditions in a sample of outpatients with PD. A total of 111 patients, diagnosed with PD, were studied. Disease duration, treatment, cardiovascular risk factors, UPDRS I-IV and Scopa Aut scale scores were reported. Subjects underwent 24-h ambulatory blood pressure (BP) monitoring and were assessed for orthostatic hypotension. We compared our results with those published in 17,219 patients using the same protocol and the same type of device. Overall, 71.1 % had no proper circadian rhythm. This frequency was significantly higher than that of the control population (48 %). The prevalence of the nondipper or riser patterns was higher in patients with orthostatic hypotension (77.8 vs. 66.7 %). There was a correlation between nightly increases in diastolic blood pressure and changes in BP during the orthostatic test. Patients taking higher doses of treatment had less decreases in SBP (cc:-0.25; p = 0.007) and DBP (cc:-0.33; p < 0.001) at night, however there was no relation with drug type. The majority of patients with Parkinson's disease show an altered circadian rhythm of blood pressure. Patients with a non-dipper or riser pattern on 24 h ABPM exhibited a higher prevalence of autonomic disorders (orthostatic hypotension) and received higher doses of dopaminergic treatment. A day-night variation in diastolic blood pressure was the most important marker of these findings.