Enfeeblement in Elders with Essential Tremor: Characterizing the Phenomenon and Its Role in Caregiver Burden.

Background: Individuals with essential tremor (ET), a common movement disorder, experience functional impairment, which contributes to burden experienced by their loved ones and caregivers. Some burdened caregivers report their loved ones as seeming debilitated or prematurely old, a concept that we have called enfeeblement. Using the Essential Tremor Enfeeblement Survey (ETES), we seek to characterize enfeeblement in elders with ET and assess its contribution to caregiver burden. Methods: We administered the ETES (range = 8-40, higher scores indicating more enfeeblement) and other scales to 98 caregivers of individuals with ET. Individuals with ET were also queried regarding tremors, cognitive abilities, and overall health. We then identified demographic and clinical correlates of ETES and modeled the contribution of ETES to caregiver burden (assessed using the Zarit 12-item Burden Interview [ZBI-12]). Results: Mean ETES score was 14.2 ± 6.2 (median = 12.0, range = 8.0-32.0); 26.5% of respondents endorsed at least one of the eight ETES items. Older age, greater tremor severity and disability, more functional and gait disability, more cognitive difficulty, and more depressive symptoms were associated with higher ETES scores. ETES was the strongest contributor to caregiver burden (ZBI-12) and substantially increased the variance explained in models of caregiver burden. Discussion: Enfeeblement seems to describe a previously unexplained component of caregiver burden in elders with ET. The presence of enfeeblement may contribute to greater burden and should be factored into assessments of patient and caregiver needs.

Contextualizing the pathology in the essential tremor cerebellar cortex: a patholog-omics approach.

Several morphological changes, centered in/around Purkinje cells (PCs), have been identified in the cerebellum of essential tremor (ET) patients. These changes have not been contextualized within a broader degenerative disease spectrum, limiting their interpretability. To address this, we compared the severity and patterning of degenerative changes within the cerebellar cortex in patients with ET, other neurodegenerative disorders of the cerebellum (spinocerebellar ataxias (SCAs), multiple system atrophy (MSA)], and other disorders that may involve the cerebellum [Parkinson's disease (PD), dystonia]. Using a postmortem series of 156 brains [50 ET, 23 SCA (6 SCA3; 17 SCA 1, 2 or 6), 15 MSA, 29 PD, 14 dystonia, 25 controls], we generated data on 37 quantitative morphologic metrics, which were grouped into 8 broad categories: (1) PC loss, (2) heterotopic PCs, (3) PC dendritic changes, (4) PC axonal changes (torpedoes), (5) PC axonal changes (other than torpedoes), (6) PC axonal changes (torpedo-associated), (7) basket cell axonal hypertrophy, (8) climbing fiber-PC synaptic changes. Our analyses used z scored raw data for each metric across all diagnoses (5772 total data items). Principal component analysis revealed that diagnostic groups were not uniform with respect to cerebellar pathology. Dystonia and PD each differed from controls in only 2/37 metrics, whereas ET differed in 21, SCA3 in 8, MSA in 19, and SCA1/2/6 in 26 metrics. Comparing ET with primary disorders of cerebellar degeneration (i.e., SCAs), we observed a spectrum of changes reflecting differences of degree, being generally mild in ET and SCA3 and more severe in SCA1/2/6. Comparative analyses across morphologic categories demonstrated differences in relative expression, defining distinctive patterns of changes in these groups. Thus, the degree of cerebellar degeneration in ET aligns it with a milder end in the spectrum of cerebellar degenerative disorders, and a somewhat distinctive signature of degenerative changes marks each of these disorders.

Inferior Olivary nucleus degeneration does not lessen tremor in essential tremor.

BACKGROUND: In traditional models of essential tremor, the inferior olivary nucleus was posited to play a central role as the pacemaker for the tremor. However, recent data call this disease model into question. CASE PRESENTATION: Our patient had progressive, long-standing, familial essential tremor. Upper limb tremor began at age 10 and worsened over time. It continued to worsen during the nine-year period he was enrolled in our brain donation program (age 85 - 94 years), during which time the tremor moved from the moderate to severe range on examination. On postmortem examination at age 94, there were degenerative changes in the cerebellar cortex, as have been described in the essential tremor literature. Additionally, there was marked degeneration of the inferior olivary nucleus, which was presumed to be of more recent onset. Such degeneration has not been previously described in essential tremor postmortems. Despite the presence of this degeneration, the patient's tremor not only persisted but it continued to worsen during the final decade of his life. CONCLUSIONS: Although the pathophysiology of essential tremor is not completely understood, evidence such as this suggests that the inferior olivary nucleus does not play a critical role in the generation of tremor in these patients.

Routine preoperative laboratory testing in elective pediatric cardiothoracic surgery is largely unnecessary.

OBJECTIVE: Routine preoperative laboratory testing (RLT) is common practice in pediatric cardiothoracic surgery and is associated with significant cost burden to patients and families. We sought to examine the value of RLT in patients undergoing elective pediatric cardiothoracic surgery. METHODS: We conducted a retrospective study of all scheduled elective pediatric cardiothoracic surgery at our institution from 2012 to 2014. Inpatients were excluded. Patient charts were reviewed to obtain preoperative laboratory values and determine relationship to case cancellation. RLT includes complete blood count, prothrombin time, partial thromboplastin time, urinalysis, 7 chemistry metabolic panel, electrocardiogram, and 2-view chest radiograph. RESULTS: RLT was completed for 1106 scheduled elective cases. Six (0.5%) cancellations were related to abnormal preoperative laboratory test results: 5 complete blood counts and 1 urinalysis. Hospital charge for RLT averaged $2064 per patient. Based on this incidence, we estimated that 184 routine preoperative laboratory tests, which generated a total hospital charge of $379,776, were required to capture 1 abnormal test significant enough to cancel surgery. An estimated charge of $2,169,552 was generated on prothrombin time, partial thromboplastin time, 7 chemistry metabolic panel, electrocardiogram, and 2-view chest radiograph, and none of these tests resulted in a cancellation. CONCLUSIONS: RLT does not significantly impact decision-making in elective pediatric cardiothoracic surgery. The decision to order a specific screening test should be clinically driven. Selective preoperative laboratory testing may have a positive impact on healthcare costs without affecting outcomes.