Clinical Autonomic Research最新文献

Background: Postural orthostatic tachycardia syndrome (POTS) is a complex disorder with serious health consequences, while its etiology remains largely elusive.

Objective: The purpose of this study was to investigate the genetic landscape of POTS using genomic approaches in a unique pediatric cohort.

Methods: We conducted a combined genome wide genotyping and whole exome sequencing (WES) study to systemically examine the molecular mechanisms of POTS pathogenesis. The patients were genotyped as two independent cohorts: a family cohort of 100 complete families and a case-control cohort of 207 unrelated European cases and 4063 ethnicity-matched control subjects. The WES component consisted of a subset of the genotyped subjects, including 87 unrelated European cases and 2719 unrelated European control subjects.

Results: The heterogeneous phenotype of POTS made achieving genome-wide significance improbable. Instead, 5670 SNPs with nominal significance (P < 0.05) were identified in both the family and case-control cohorts, with effects in the same direction. We conducted an over-representation analysis (ORA) by considering all genes that showed nominal significance. The ORA identified gene sets linked to cell-cell junction, early estrogen response, and substance-related disorders with statistical significance. Moreover, WES revealed 55 genes with genome-wide significance through rare variant burden analysis, harboring 92 variants classified as pathogenic or likely pathogenic by ClinVar.

Conclusions: This study showcases the complex interplay between common and rare genetic variants in POTS development, marking a pioneering step forward in deciphering its complex etiologies. The insights from this research enrich our understanding of POTS, offering new avenues for precise treatment strategies and highlighting areas for further research.

Purpose: This study examined occupational histories in multiple system atrophy to identify environmental associations of potential relevance to disease causation.

Methods: A total of 270 neuropathologically confirmed cases of multiple system atrophy obtained from the Mayo Clinic Brain Bank for neurodegenerative disorders in Jacksonville, Florida, were included in this case-control study. Demographic and disease information was collected from medical records. Information regarding occupational history was collected retrospectively from medical records and published obituaries. Proportions of employment by occupational sector were compared with US census data.

Results: When comparing patients with US census data, significant differences were identified for education (15.2% versus 2.3%, P < 0.001), administration (14.8% versus 4.1%, P < 0.001), clerical (10.7% versus 5.5%, P = 0.001), petroleum industry (8.9% versus 5.6%, P = 0.024), metal industry (7.8% versus 3.0%, P < 0.001), electrical engineers and electricians (5.6% versus 0.4%, P < 0.001), civil or mechanical engineering (4.4% versus 0.2%, P < 0.001), real estate (4.4% versus 0.7%, P < 0.001), information technology (4.1% versus 1.8%, P = 0.011), woodworking (3.0% versus 0.03%, P < 0.001), writing or publishing (2.6% versus 0.3%, P < 0.001), law (2.2% versus 0.4%, P = 0.001), hairdressing (0.7% versus 0.1%, P = 0.03), and social work (0.7% versus 0.1%, P = 0.03).

Conclusions: The listed occupational categories were significantly overrepresented in our series of patients with multiple system atrophy as compared with population data. We hypothesize that these occupational associations may signify environmental exposures, increasing the disease risk in genetically susceptible individuals. We cannot exclude a potential selection bias in patients willing to donate their brains to an academic center to contribute to scientific knowledge.

Purpose: The aim of this study was to investigate the relationship between cardiac autonomic dysfunction, cognitive impairment, and survival in patients with amyotrophic lateral sclerosis (ALS).

Methods: The heart activity of 65 patients with ALS (28 with normal cognition [ALS-CN]; 37 with impaired cognition [ALS-CI]) and 38 healthy controls (HCs) was measured by 24-h Holter monitoring. Heart rate (HR) measures and heart rate variability (HRV) parameters were compared between the three study groups and, additionally, correlated with five Edinburgh Cognitive and Behavioral ALS Screen (ECAS) domains in the ALS subgroups. Age, gender, and educational level were adjusted. Factors associated with cognitive status were assessed using logistic regression. Survival predictors in patients with ALS were analyzed using the Kaplan-Meier estimator and Cox regression.

Results: Compared to the HCs, patients with ALS-CI exhibited lower RRI (R-R-interval; P = 0.017), SDNN (standard deviation of all normal RR intervals; P = 0.013), SDNN Index (P = 0.044), and VLF power (very low-frequency power; P = 0.012). Total power was reduced in the ALS-CI group compared to the HCs (P = 0.036) and ALS-CN group (P = 0.048). In patients with ALS-CN, language negatively correlated with mean HR (P = 0.001) and positively with the RRI (P = 0.003), SDNN (P = 0.001), SDANN (standard deviation of the average NN intervals; P = 0.005), total power (P = 0.006), VLF power (P = 0.011), and low-frequency power (P = 0.026). Visuospatial function correlated positively with the SDNN Index (P = 0.041). In patients with ALS-CI, executive function (P = 0.015) and ECAS total score (P = 0.009) negatively correlated with the RMSSD (square root of mean sum-of-squares of differences between adjacent NN intervals), while visuospatial function correlated positively with normalized LF value (LFnu; P = 0.049). No associations were observed between the other cognitive domains and any of the 14 HRV/HR measures in patients with either ALS-CI or ALS-CN. SDNN ≤ 100 ms was linked to cognitive impairment (P = 0.039) and also showed a borderline association (P = 0.066) with poorer survival, while cognitive impairment (P = 0.010) was significantly linked to worse outcomes.

Conclusions: Patients with ALS with cognitive impairment demonstrated reduced cardiac autonomic modulations and altered cognitive autonomic associations. Cognitive impairment was linked to reduced survival, with baseline SDNN ≤ 100 ms identified as a potential marker.

Purpose: Identifying features of patients who remain pure autonomic failure has implications on disease definition and offers insights into synucleinopathy progression. We sought to determine symptom timeline and autonomic features in patients who retain the pure autonomic failure phenotype with prolonged follow-up.

Methods: We reviewed all patients diagnosed with pure autonomic failure from 2001 to 2011 evaluated at Mayo Clinic, Rochester, with autonomic reflex screen and over 1 year of in-person follow-up. Clinical evaluations and patient telephone calls were used to assess timeline of symptoms.

Results: Of 202 patients, 133 remained pure autonomic failure with median follow-up time of 9.05 years (interquartile range (IQR) 4.2-13.1). Additional autonomic symptoms included constipation (N = 60; 45%), bladder symptoms (N = 78; 59%), which were severe in 50 patients (37.6%) with incontinence or requiring catheterization, sexual dysfunction (N = 53; 40%) and thermoregulatory dysfunction (N = 51; 38%). Assessment of dream enactment behavior was completed in 86 patients and endorsed in 45 patients (52%). Median time to dream enactment behavior onset from orthostatic hypotension was 7.00 years (1.55-13.50). Other autonomic symptoms tended to occur near orthostatic hypotension. Autonomic testing showed moderate to severe autonomic failure with median composite autonomic score of 6 (IQR 4-8; N = 133) and median percentage anhidrosis of 51% (IQR 3-93%; N = 105).

Conclusions: Patients with pure autonomic failure typically have symptom onset near development of orthostatic hypotension while dream enactment behavior may occur later. Our findings underscore that not all patients with pure autonomic failure will develop motor or cognitive symptoms, even with prolonged follow-up.

Aim: Individuals with spinal cord injury (SCI) have an increased prevalence of orthostatic hypotension (OH). Diagnosis of OH is made with active standing or tilt table testing, with limited the use in individuals with SCI.

Methods: An alternative approach to assess OH is the sit-up test, which involves passive repositioning from the supine to the seated position. The purpose of this study was to document the reliability and validity of the sit-up test, and determine whether the level or severity of injury related to orthostatic blood pressure (BP) responses in a large, diverse group of individuals with SCI.

Results: A total of 166 participants-119 individuals with SCI and 47 uninjured control-completed two sit-up tests, and 36 individuals who completed the sit-up tests also underwent a head-up tilt test. Change in BP from sit-up test 1 to sit-up test 2 was not significantly different for either systolic BP or diastolic BP. Neither level nor severity of injury contributed to the reliability assessments, which showed disappointing results with generally low interclass correlation coefficients (ICC), with values ranging from 0 to 0.63, and large standard error of measurements (SEM), ranging from 5.2 to 13.7 mmHg. Comparison between BP responses to the sit-up test and the head-up tilt showed good sensitivity and specificity, with positive predictive values > 75%.

Conclusion: Prevalent BP instability likely contributed to the poor reliability of the sit-up test, but the test is easy to perform with a high likelihood ratio for the valid assessment of OH in individuals with SCI.

Clinical trial registration: NCT01758692.