Effect of the use of earplugs and eye masks on the quality of sleep after major abdominal surgery: a randomised controlled trial

Significant sleep disturbance can occur following major abdominal surgery. We aimed to evaluate the effectiveness of earplugs and eye masks in improving sleep quality and patient satisfaction, reducing nursing demands and in the incidence of delirium in patients after major abdominal surgery. We conducted a randomised controlled trial in 100 patients undergoing major abdominal surgery. We randomly allocated participants to sleep with or without earplugs and eye masks on postoperative days 1-3. The primary outcome measure was sleep quality as measured by the Richards-Campbell Sleep Questionnaire. Secondary outcomes were patient satisfaction, frequency of nursing demand and incidence of delirium measured by the Neelon and Champagne Confusion Scale. Median (IQR [range]) sleep scores were 64 (38-74 [0-100] and 60 (44-82 [18-100]) for the control and intervention groups, respectively (p = 0.310). Age and Pittsburgh Sleep Quality Index scores were found to be significant factors affecting sleep quality. There were no differences in patient satisfaction, reduction in frequency of nursing demands or incidence of delirium on postoperative days 1-3 after major abdominal surgery. The compliance rate in the intervention group was 60-65%. This study has demonstrated that the use of earplugs and eye masks did not contribute to improvements in sleep quality. Of note, sleep quality was moderate, with higher age and worse baseline sleep quality contributing to worse sleep scores. More studies are needed to investigate interventions to improve sleep quality after major abdominal surgery.

Rapid degradation of psychomotor memory causes poor quality chest compressions in frequent cardiopulmonary resuscitation providers and feedback devices can only help to a limited degree: A crossover simulation study

Studies report a decline in the psychomotor memory of cardiopulmonary resuscitation (CPR) providers within months of training, but they are prone to subject bias. We hypothesized that this degradation is faster and more prevalent in real world practice. The aims of our study were to 1. assess the quality of chest compressions (CC) delivered routinely by CPR-certified clinicians who are not primed by study conditions, and 2. investigate if psychomotor memory degrades if feedback devices are removed. Forty anaesthetists and intensivists participated in a voluntary, half-day, randomized crossover study using case-based simulation. Participants were paired and randomly assigned into 2 groups; each receiving automated feedback either in the first or second cycle of CPR. Two cycles of CC and defibrillation (ACLS protocol) were administered on a manikin. CC parameters including overall quality were measured by a feedback device. The median proportion of good quality CC was poor at baseline but improved with feedback; 38.2% (IQR 27.7, 58.7) to 57.7% (IQR 38.0, 68.7), P < .05. The median proportion of good quality CC fell after feedback withdrawal; 50.5% (IQR 24.5, 67.7) to 25.6% (9, 37.6), P < .05. No carryover effect was observed. Treatment effect and period effect were detected. Baseline quality of CC amongst frequent CPR providers is poor, and can be improved partly by feedback devices. As psychomotor memory of good quality CCs degrades rapidly after removal of feedback, a multimodal approach is required for CPR skill retention. Future research on the optimal frequency of CPR training, including the use of feedback devices in clinical practice should be explored.

Effectiveness of 3-in-1 Continuous Femoral Block of Differing Concentrations Compared to Patient Controlled Intravenous Morphine for Post Total Knee Arthroplasty Analgesia and Knee Rehabilitation

We assessed the effectiveness of the 3-in-l continuous femoral block as a form of postoperative pain relief for unilateral total knee arthroplasty (TKA). Sixty patients undergoing elective unilateral TKA under subarachnoid block were randomized into three groups. Postoperative analgesia was provided with a continuous 3-in-l femoral nerve catheter with 0.15% ropivacaine in group A, a continuous 3-in-l femoral nerve catheter with 0.2% ropivacaine in group B, or patient controlled intravenous morphine in group C (control group). Groups A and B received patient controlled intravenous morphine pumps for rescue analgesia. Patients in each group were followed for 72 hours postoperatively. Five patients were excluded after randomization. In the remaining 55 patients there was no statistical difference in pain score between the groups. Total morphine use was highest in group C (P< 0.05). No appreciable difference could be found with sensorimotor blockade, morphine usage and satisfaction scores when comparing groups A and B. Femoral catheter dislodgement rate was 7.9%. There was no statistical difference between the groups when comparing the day of first ambulation and the time to discharge from the hospital. Satisfaction scores were higher in group A (P = 0.028) and group B (P = 0.002) compared to group C. We conclude that a continuous 3-in-l femoral nerve block with ropivacaine 0.15% or 0.2% for elective unilateral TKA has an opioid-sparing effect.

An overview of lower limb cellulitis in an acute medical ward-a few lessons we can learn

Lower limb cellulitis is a common cause for hospital admissions. In this retrospective study, we assessed the characteristics and outcome of patients admitted in an acute medical unit. The mean duration of treatment was 10.48 days, with 95.5% receiving antibiotics for more than 5 days. Mean length of stay (LOS) was 5.19 days. 12-month readmission rate was higher in patients with diabetes, chronic kidney disease (CKD) and previous stroke. Diabetes, CKD, previous stroke, and elevated procalcitonin levels were independently associated with prolonged admission (>3 days).

Use of a Load Distributing Band Device (with Ventilation Prompts) during Cardiopulmonary Resuscitation

Introduction

Over-ventilation can compromise coronary perfusion pressures during cardiopulmonary resuscitation (CPR) and should be minimised. We compared ventilations during manual and mechanical (load-distributing band - LDB) CPR, which gives ventilation prompts. Our primary objective was to compare the ventilation rate between manual CPR and LDB-CPR.

Method

This was a phased, non-randomised study at a tertiary hospital emergency department. All out-of-hospital, non-traumatic cardiac arrest adult patients during the study period from February 2007 till July 2008 were eligible. Pregnant females and patients aged less than 18 years of age were excluded. Ventilation rates in the first and second 5 minutes segments were recorded. Over-ventilation was defined as ventilation rate above 12 breaths per minute. All data analyses were performed with SPSS, version 17.0. Mean differences with 95% confidence interval (CI) were compared between the 2 treatment groups.

Results

From February 2007 till August 2007, there were 29 patients with manual CPR; and from September 2007 till July 2008, there were 62 with LDB-CPR. In the first 5 minutes of CPR, the proportion of patients that were over-ventilated, was 27.6% (manual) and 4.8% (LDB) (difference = 22.7%; 95% CI: 3.5-46.4%). In the next 5 minutes, the proportion of patients that were over-ventilated was 37.9% and 1.6% for manual and mechanical CPR respectively (difference = 36.3%; 95% CI: 16.5-58.9%).

Conclusion

Over-ventilation is reduced significantly in LDB-CPR compared to manual CPR during the first and second 5 minutes of resuscitation.

Predictive Value of Electrophysiology for Presence of Thymic Pathology in Myasthenia Gravis

OBJECTIVE

Single fibre electromyography (SFEMG) and repetitive nerve stimulation (RNS) are routinely performed investigations in evaluation of patients with myasthenia gravis (MG). Significant number of MG patients have a thymic pathology. We aimed to explore the relationship between the SFEMG and RNS findings with the presence of thymic pathology.

METHODS

We studied 159 consecutive patients with MG over a 10 year period. The SFEMG parameters - mean jitter (MJ) and percentage of abnormal fibres (POAF) and the RNS result were correlated with the thymic findings.

RESULTS

As compared to patients with normal thymus (MJ:58.3 μsec; POAF:63.5%), patients with thymic pathology had a significantly higher MJ (80.9 μsec; p &lt; 0.0005) and POAF (83.5%; p &lt; 0.0005). MG patients with thymic hyperplasia had the highest MJ (87.6 μsec) and POAF (84.4%) followed by patients with thymoma (MJ:78.6 μsec; POAF:83.2%). The MJ and POAF did not correlate with the stage of thymoma. Mean jitter values above 34.9 μsec and POAF above 31% had 100% sensitivity for the presence of thymic pathology. A positive RNS increased the risk of thymic pathology (OR = 3.9, CI = 1.8-8.5) and thymoma. (OR = 3.5; CI = 1.5-8.1).

CONCLUSION

Electrophysiology could be valuable complimentary tool to identify MG patients at high risk for thymic pathology. However, it does not aid us to identify the exact thymic pathology and does not correlate with the stage of thymoma. All OMG patients with higher MJ and PAOF values should also be screened for thymoma. The results reinforce the immunological role of thymic pathology in neuromuscular transmission interference.

ACE gene sequence and nucleotide variants in IgA nephropathy

INTRODUCTION

Association studies with single nucleotide polymorphisms (SNPs) have been contradictory. Haplotypes may be more helpful. With gene sequencing, all SNPs can be found for construction of haplotypes.

METHODS

The ACE gene was sequenced in four healthy Chinese subjects and 20 patients with IgA nephropathy (IgAN) to observe if differences exist among SNPs and haplotypes. 20 patients on angiotensin 1-converting enzyme inhibitor/angiotensin receptor antagonist (ACEI/ATRA) therapy were then compared with another 20 patients not treated with ACEI /ATRA to determine their renal outcome in response to ACEI/ATRA therapy and whether their genetic profile of ACE gene could play a role in determining their outcome to ACEI /ATRA therapy and progression to end-stage renal failure (ESRF).

RESULTS

IgAN patients had 53 variants, of which 17 were unique, whereas normal subjects had 38 variants, of which two were unique (p less than 0.005). No unique variant was a significant risk factor for IgAN. Significant genotype and allele frequency differences in five variants were observed between IgAN patients with renal impairment and those with ESRF (p less than 0.02).

CONCLUSION

Our data suggests that at least in the ACE gene, haplotyping SNPs within a single gene seems to have no added advantage over genotyping the individual component SNPs. The D allele and haplotype 3 confer an adverse prognosis, while the I allele and haplotype 5 appear to be renoprotective. The data suggests that genotypes of the ACE gene are linked to certain haplotypes, which could influence IgAN patients' response to ACEI/ATRA therapy.

Ovarian hyperstimulation syndrome: an analysis of patient characteristics in the Asian population

INTRODUCTION

We aimed to identify the variables associated with ovarian hyperstimulation in Asian patients and compare them with western standards.

METHODS

This is a retrospective case record analysis of 79 patients with ovarian hyperstimulation at a tertiary restructured hospital.

RESULTS

Gonadotropin doses resulting in hyperstimulation did not vary between long and antagonist cycles in women less than 35 years with polycystic ovaries (PCO). Mean oestradiol levels at hyperstimulation were not different between PCO and non-PCO patients in a long cycle. Hyperstimulation was mostly due to higher starting doses. Total follicle counts of more than 20 on Day 5-7 after stimulation may be predictive of subsequent hyperstimulation. Hyperstimulation tended to be more severe in lean PCO patients, and prophylactic albumin helped to reduce its severity.

CONCLUSION

Gonadotropin doses at stimulation should start at 150 iu or less in women below 35 years of age, with a step up of 37.5 iu, as necessary. Transfer should be abandoned in the presence of high oestradiol levels (more than 5,000 pg/ml), when the total number of intermediate and large follicle count exceeds 30 on the day of oocyte retrieval, or when more than 19 eggs are retrieved. Variables in the Asian population appear to be similar to those in the western population.

A pilot study of topiramate dosages for migraine prophylaxis in an Asian population

Topiramate is known to be efficacious in migraine prophylaxis, but its optimal dose has not been systematically studied in the Asian population. Here, we show that a fixed low dose of topiramate 25 mg/day is efficacious in migraine prophylaxis and also attest to advantages in terms of medication cost savings and more favourable side effect profile.

Clinical and physiological effects of transcranial electrical stimulation position on motor evoked potentials in scoliosis surgery

Background

During intraoperative monitoring for scoliosis surgery, we have previously elicited ipsilateral and contralateral motor evoked potentials (MEP) with cross scalp stimulation. Ipsilateral MEPs, which may have comprised summation of early ipsilaterally conducted components and transcallosally or deep white matter stimulated components, can show larger amplitudes than those derived purely from contralateral motor cortex stimulation. We tested this hypothesis using two stimulating positions. We compared intraoperative MEPs in 14 neurologically normal subjects undergoing scoliosis surgery using total intravenous anesthetic regimens.

Methods

Trancranial electrical stimulation was applied with both cross scalp (C3C4 or C4C3) or midline (C3Cz or C4Cz) positions. The latter was assumed to be more focal and result in little transcallosal/deep white matter stimulation. A train of 5 square wave stimuli 0.5 ms in duration at up to 200 mA was delivered with 4 ms (250 Hz) interstimulus intervals. Averaged supramaximal MEPs were obtained from the tibialis anterior bilaterally.

Results

The cross scalp stimulating position resulted in supramaximal MEPs that were of significantly higher amplitude, shorter latency and required lower stimulating intensity to elicit overall (Wilcoxon Signed Rank test, p < 0.05 for all), as compared to the midline stimulating position. However, no significant differences were found for all 3 parameters comparing ipsilaterally and contralaterally recorded MEPs (p > 0.05 for all), seen for both stimulating positions individually.

Conclusions

Our findings suggest that cross scalp stimulation resulted in MEPs obtained ipsilaterally and contralaterally which may be contributed to by summation of ipsilateral and simultaneous transcallosally or deep white matter conducted stimulation of the opposite motor cortex. Use of this stimulating position is advocated to elicit MEPs under operative circumstances where anesthetic agents may cause suppression of cortical and spinal excitability. Although less focal in nature, cross scalp stimulation would be most suitable for infratentorial or spinal surgery, in contrast to supratentorial neurosurgical procedures.

High-resolution ultrasound in the evaluation and prognosis of Bell's palsy

INTRODUCTION

Bell's palsy is a commonly encountered paralysis of the facial nerve occurring worldwide. Prognosis for Bell's palsy is good, but the proportion of patients with poor outcomes may reach 30%. Ultrasound (US) may provide a novel approach for evaluating and prognosticating Bell's palsy, in comparison with known electrophysiological techniques.

METHODS

In this study, we measured the diameter of the distal facial (VII) nerve using US in patients with Bell's palsy treated with prednisolone, in comparison with healthy controls. Blink reflex and VII nerve conduction studies were also performed. Studies were prospective and performed within 1 week of disease onset.

RESULTS

Our results have shown that diameter of the distal VII nerve is a good predictor of favorable (positive predictive value: 100%) and bad outcomes (negative predictive value: 77%) in Bell's palsy at 3 months after clinical presentation. Furthermore, we also noted the lack of correlation of VII diameter with conventional VII nerve conduction studies (NCS) and blink reflex studies. US was superior to VII nerve conduction and blink reflex studies in outcome prediction.

CONCLUSIONS

This first study utilizing US in Bell's palsy highlights its role in outcome prediction and contributes to our understanding of recovery processes in this common neurological disorder.

Electrophysiological evidence of cerebellar fiber system involvement in the Miller Fisher syndrome

BACKGROUND

In the Miller Fisher syndrome (MFS), ataxia may be due involvement of Ia afferents and the cerebellum. Transcranial magnetic stimulation (TMS) over the cerebellum is known to interfere transiently with normal function.

METHODS

In this study, we utilized a previously described TMS protocol over the cerebellum in combination with ballistic movements to investigate cerebellar dysfunction in MFS patients.

RESULTS

The agonist (biceps) reaction time in MFS patients during a motor cancellation task was not significantly reduced during the initial TMS study. However, during the repeat TMS study, significant reduction was seen for all patients, in tandem with clinical recovery. There was significant correlation between anti-GQ1b IgG titers and change in agonist reaction time between the initial and repeat TMS studies.

CONCLUSIONS

TMS likely affected horizontally orientated parallel fibers in the cerebellar molecular layer. During disease onset, antibody binding may have interfered with facilitation of reaction time during motor cancellation tasks seen in normal subjects. Normalization of reaction time facilitation corresponded to resolution of antibody-mediated interference in the molecular layer. Our study has provided evidence suggesting parallel fiber involvement in MFS, and suggested a role of anti-GQ1b IgG antibody in these changes.

Three-dimensional MR volumetric analysis of the posterior fossa CSF space in hemifacial spasm

BACKGROUND

We hypothesize that a smaller posterior fossa (PF) CSF space may be a risk factor for hemifacial spasm (HFS).

OBJECTIVE

We conducted a case-control 3-dimensional magnetic resonance (MR) volumetric study in patients with HFS and determined the clinical predictive factors of PF CSF volume.

METHODS

Patients with clinically diagnosed HFS and controls matched for age, sex, race, and hypertension underwent MRI/magnetic resonance angiography examination. The PF CSF space was segmented and quantified on a heavily T2-weighted high-resolution 3-dimensional MR volume slab, centered over the porus acusticus.

RESULTS

Eighty-two study subjects (41 patients and 41 controls) were included. The mean PF CSF volume in patients with HFS and controls was 17,303.0 +/- 3,900.0 vs 19,216.0 +/- 3,912.0 mm(3). The mean volume in patients with HFS was 11.4% smaller than in controls (p = 0.015). Analysis of differences between individually matched pairs and controls also revealed that PF CSF for controls was larger than that for patients with HFS (p = 0.007). A multivariate linear regression analysis revealed that a small PF CSF volume was associated with HFS (p = 0.01). Decreasing age (p = 0.001) and female gender (p < 0.0005), but not hypertension (p = 0.892), were also found to be predictors of a low PF CSF volume.

CONCLUSIONS

Our results showed that the posterior fossa (PF) CSF volume was lower in patients with HFS compared with matched controls. HFS, female gender, and younger age were associated with smaller PF CSF volume. These observations could explain the strong female preponderance in both clinic- and population-based epidemiologic studies.

CALHM1 variant is not associated with Alzheimer's disease among Asians

In a case control study involving 484 study subjects, we showed that the CALHM1 allele (13.5% vs 16.7%) and genotype frequency was not significantly different between Alzheimer's disease (AD) and controls. Logistic regression analysis did not reveal any interaction between ApoE4 allele and CALHM1 allele.

Analysis of the UCHL1 genetic variant in Parkinson's disease among Chinese

The inverse association of the functional ubiquitin carboxy-terminal hydrolase L1 (UCHL1) S18Y variant with Parkinson's disease (PD) among Caucasian populations has been debated. We conducted a large-scale analysis to investigate the age-of-onset effect of the UCHL1 variant in PD among ethnic Chinese. Individual data sets from 5 centers comprising a total of 4088 study subjects were analyzed. In the univariate analysis, only data from 1 center showed a trend towards a protective effect among young subjects. However, in the combined analysis, no significant association between the UCHL1 variant and PD was detected (A allele frequency 0.531 vs. 0.528, p=0.87, OR 1.01, 95% CI 0.92-1.1). Among subjects less than 60 years old, the OR is 0.99 (95% CI 0.84-1.16, p=0.88). A multivariate logistic regression analysis showed that family history, UCHL1 variant and the interaction of UCHL1 variant and age at onset (p=0.816) were not significantly associated with PD.

Graves ophthalmopathy: the bony orbit in optic neuropathy, its apical angular capacity, and impact on prediction of risk

BACKGROUND AND PURPOSE

Optic neuropathy (ON), a serious complication of Graves ophthalmopathy, is often subclinical and masked by symptoms of orbitopathy. We examined herein bony and soft-tissue CT features associated with ON, including an angular assessment of orbital apex capacity, and their usefulness in the risk prediction of ON.

MATERIALS AND METHODS

The CT scans of 41 patients with Graves ophthalmopathy (17 men, 24 women; mean age, 49.1 years) clinically diagnosed with (19 patients, 32 orbits) or without ON were evaluated by 2 independent raters. Quantitative linear and angular measurements of the orbital structures and bony walls and categoric scores of apical crowding and intracranial fat prolapse were assessed on a clinical workstation. Inter- and intrarater variability of these features was determined. The CT features of the 2 patient groups were compared, and multivariate logistic regression analysis was performed to evaluate the predictive features of ON.

RESULTS

Bony orbital angles (P < .005), length of the lateral orbital wall (P < .05), muscular diameters (P < .0005), muscular bulk of the medial rectus muscle relative to the bony orbit (P < .05), and apical crowding (P < .0005) were associated with clinical ON. Stepwise multivariate logistic regression analysis revealed the muscle diameter index and medial and lateral wall angles to be independent predictors. Combining these in a single multivariate equation yielded sensitivity, specificity, and positive and negative predictive values of 73%, 90%, 82%, and 85%, respectively.

CONCLUSIONS

Orbital wall angles, especially the medial wall, and muscular enlargement are independent risk predictors.

Clinical correlates of phosphene perception in migraine without aura: An Asian study

INTRODUCTION

Although controversy exists with regard to the presence of hypoexcitability versus hyperexcitability of the visual cortex in migraine patients, there remain a group who do not perceive phosphenes (P-). However, its clinical implications have not been systematically addressed. In this study, we hypothesize that P- patients classified as migraine without aura (MO) have distinct clinical features.

METHODS

Twenty-nine Asian MO patients (7 men; mean age: 44; median: 45; range: 25 to 65) were consecutively entered into the study. Visual cortex transcranial magnetic stimulation (TMS) was performed in the migraine interictum.

RESULTS

Of the 19 patients, 19 (66%) were able to perceive phosphenes (P+), while 10 (34%) were not able to after repeated TMS (P-). P- patients had significantly higher headache frequency (p=0.008) and pain score (p=0.002) compared with P+ patients. In addition, there was significant positive correlation of phosphene threshold with pain score (r=0.52, p=0.02) in P+ patients. There was no significant difference between P+ and P- patients in terms of age (t-test, p=0.6).

CONCLUSIONS

Our study is inkeeping with the hypothesis that interictal visual cortex excitability is reduced in relation to the severity of migraine in Asian MO patients, and lack of phosphene perception may be related to significantly elevated thresholds beyond the output of TMS stimulators.

Case control study of diffusion tensor imaging in Parkinson's disease

BACKGROUND

Preliminary work has shown that diffusion tensor MRI (DTI) may contribute to the diagnosis of Parkinson's disease (PD).

OBJECTIVES

We conducted a large, prospective, case control study to determine: (1) if fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values on DTI in the basal ganglia and substantia nigra are different between patients with PD and healthy controls; and (2) the predictive value of these parameters and their clinical utility.

METHODS

DTI imaging was carried out in patients with PD and controls. FA and ADC values were obtained from various brain structures on the DTI scan using the diffusion tensor taskcard. The structures studied were: caudate, putamen, globus pallidus, thalamus and substantia nigra.

RESULTS

151 subjects (73 PD patients, 41 men, 32 women; mean age 63.6 years) and 78 age and sex matched control subjects were studied. The FA value of the substantia nigra in patients with PD was lower compared with controls (0.403 vs 0.415; p = 0.001). However, no significant differences were demonstrated for FA or ADC values of other structures. Multiple regression analysis revealed that the clinical severity of PD correlated inversely with the FA value in the substantia nigra in patients with PD (regression coefficient -0.019). No single FA value had both a high positive and negative predictive power for PD.

CONCLUSIONS

We demonstrated in a large, prospective, case control study that the FA value in the substantia nigra on DTI was lower in PD compared with healthy controls, and correlated inversely with the clinical severity of PD. Further longitudinal studies would be helpful to assess the clinical utility of serial FA measurements of the substantia nigra in objective quantification of disease progression and monitoring of the therapeutic response.

Intersensory facilitation in rapid single-joint voluntary activation and cancellation of arm movements

The ability to initiate and cancel actions is a basic requirement for motor control in humans. Rapid movements to stationary targets over single joints are characterized by triphasic bursts of electromyographic (EMG) activity. While analysis of reaction time in motor activation tasks, in relation to different modalities of sensory inputs, has studied, its diametrically opposite task of motor cancellation has not been adequately addressed. We studied 9 normal right-handed subjects using biceps (agonist) and triceps (antagonist) EMG recordings. Each underwent 3 motor activation and 3 motor cancellation tasks to light, sound and dual stimuli (6 blocks). The former consisted of ballistic elbow flexion over 45 degrees, while the latter involved dropping of the forearm from a 45-degree elbow flexion angle. For motor activation, onset latencies and duration of agonist (Lat1, Dur1) and antagonist (Lat2, Dur2) muscles were recorded. For motor cancellation, onset latencies and duration of agonist (Lat1 only) and antagonist (Lat2, Dur2) were noted. Motor cancellation showed significantly shorter Dur2 EMG bursts (p < .0005) for all 3 stimuli conditions. Lat1 and Lat2 demonstrated significant correlation (p < 0.0005 for all), with the exception of dual stimulus condition during motor cancellation (p = 0.089). While dual stimulus during motor cancellation resulted in significantly shorter Lat2 (p = .013) in comparison with light and sound stimuli, this was not evident for motor activation tasks. The findings suggest that while a common central program exists for executing motor activation and cancellation, generation of antagonist activity in the latter may involve distinct neural pathways specifically robust to the effects of intersensory facilitation. This is discussed in relation to reciprocal motor oscillatory activity manifestations at the level of single joint movements.

Comparing knowledge and attitudes towards genetic testing in Parkinson's disease in an American and Asian population

INTRODUCTION

Recent discoveries of disease-causing genes in Parkinson's disease (PD) have generated considerable interest regarding genetic testing in PD. The attitudes toward genetic testing are largely influenced by knowledge and preconceived notions.

OBJECTIVE

We investigated the relationship between knowledge of and attitude towards predictive genetic testing of PD in two independent centers in America and Asia involving PD patients and caregivers.

METHODS

In a prospective study involving 515 subjects comprising of PD patients and their caregivers in two independent centers in America and Asia, the level of knowledge about genetic testing and patients' attitudes towards such testing were evaluated using a standardized questionnaire.

RESULTS

American PD patients had a higher level of knowledge of PD genetics than Asian PD (31.1% vs. 12.3%, p=0.0002). A greater number of American PD patients and caregivers reported a positive attitude towards the potential medical benefits of genetic testing compared to their Asian counterparts (85.4% vs. 42.2%, 92.2% vs. 32.1%, p<0.00005), but a more negative attitude towards potential compromise in getting health and life insurance (43.7% vs. 25.8%, p=0.0002). However, in the Asian cohort, multivariate analysis revealed that a high level of genetics knowledge was associated with a positive attitude response regarding the potential medical benefits of testing (p<0.0005), but a negative attitude towards compromises in healthcare and life insurance, getting a job and starting a family (p<0.0005). These associations were not observed amongst American subjects.

CONCLUSIONS

The relationship between level of genetic knowledge and attitude towards potential risks and benefits of predictive genetic testing in PD was distinctly different in two independent, racially and culturally different PD populations and caregivers. These observations have clinical implications in the development of PD genetic counseling programs.

The LRRK2 Gly2385Arg variant is associated with Parkinson’s disease: genetic and functional evidence

Evidence of LRRK2 haplotypes associated with Parkinson's disease (PD) risk was recently found in the Chinese population from Singapore, and a common LRRK2 missense variant, Gly2385Arg, was independently detected as a putative risk factor for PD in the Chinese population from Taiwan. To test the association between the Gly2385Arg variant in a large case-control sample of Chinese ethnicity from Singapore, and to perform functional studies of the wild type and Gly2385Arg LRRK2 protein in human cell lines. In a case-control study involving 989 Chinese subjects, the frequency of the heterozygous Gly2385Arg genotype was higher in PD compared to controls (7.3 vs. 3.6%, odds ratio = 2.1, 95% CI: 1.1-3.9, P = 0.014); these values yield an estimated population attributable risk (PAR) of approximately 4%. In a multivariate logistic regression analysis with the disease group (PD vs. controls) as the dependent variable and the genotype as an independent factor with adjustments made for the effect of age and gender, the heterozygous Gly2385Arg genotype remained associated with an increased risk of PD compared to wild type genotype (odds ratio = 2.67, 95% CI: 1.43-4.99, P = 0.002). The glycine at position 2385 is a candidate site for N-myristoylation, and the Gly2385Arg variant replaces the hydrophobic glycine with the hydrophilic arginine, and increases the net positive charge of the LRRK2 WD40 domain. In transfection studies, we demonstrated that both the wild type and Gly2385Arg variant LRRK2 protein localize to the cytoplasm and form aggregates. However, under condition of oxidative stress, the Gly2385Arg variant was more toxic and associated with a higher rate of apoptosis. Our study lends support to the contention that the Gly2385Arg is a common risk factor for PD in the Chinese population. Our bioinformatics and in-vitro studies also suggest that the Gly2385Arg variant is biologically relevant and it might act through pro-apoptotic mechanisms.

Intraoperative monitoring study of ipsilateral motor evoked potentials in scoliosis surgery

Ipsilateral motor evoked potentials (MEPs) in spinal cord surgery intraoperative monitoring is not well studied. We show that ipsilateral MEPs have significantly larger amplitudes and were elicited with lower stimulation intensities than contralateral MEPs. The possible underlying mechanisms are discussed based on current knowledge of corticospinal pathways. Ipsilateral MEPs may provide additional information on the integrity of descending motor tracts during spinal surgery monitoring.

Magnetic brainstem stimulation of the hypoglossal nerve in normal subjects

Electrophysiological evaluation of motor pathways to the lingual muscles is technically challenging. Previous studies utilizing transcranial magnetic stimulation (TMS) of the parieto-occipital region with a round coil reported difficulties in eliciting tongue motor responses. In this study, we utilized TMS with a double cone coil at the posterior head region to obtain tongue motor evoked potentials. Our findings suggest activation at or distal to the hypoglossal nuclear level, but proximal to the hypoglossal canal region. Our method can be usefully applied in future studies of brainstem and cranial nerve function.

Transcranial magnetic stimulation screening for cord compression in cervical spondylosis

OBJECTIVE

Cervical spondylosis (CS) often results in various degrees of cord compression, which can be evaluated functionally with transcranial magnetic stimulation (TMS). We investigate the use of TMS as a screening tool for myelopathy in CS.

METHODS

We prospectively studied 231 patients classified into Groups 1 to 4 based on MRI grading of severity of cord compromise. TMS elicited central motor conduction times and motor evoked potential (MEP) amplitudes in all 4 limbs. The results were compared with those from 45 healthy controls.

RESULTS

TMS showed 98% sensitivity and 98% specificity for cord abnormality using MRI as reference standard.

CONCLUSIONS

MEP abnormalities are useful for electrophysiological evaluation of cord compression in CS. While TMS is not a substitute for MRI, it is of value as a rapid, inexpensive and non-invasive technique for screening patients before MRI studies.

Validation of a short disease specific quality of life scale for hemifacial spasm: correlation with SF-36

BACKGROUND

A short, practical, and validated quality of life (QoL) scale for hemifacial spasm (HFS) is not currently available.

OBJECTIVES

To examine the reliability and validity of a short self-rating scale (HFS-7) by comparing HFS patients with healthy controls. We also evaluated the correlation of HFS-7 with the physical and mental domains of SF-36, a generic QoL scale.

METHODS

Seven self-rating items (HFS-7) were administered to HFS patients and healthy controls. In addition, HFS patients answered the SF-36 questionnaire. The validity and reliability of HFS-7 were analysed and correlation between HFS-7 and SF-36 examined.

RESULTS

A total of 178 subjects were enrolled in the study, including 85 HFS patients with mean age of 54.8 (SD 11.0) years, of whom 52 (61.2%) were women, and 93 controls with mean age of 51.4 (SD 10.0) years, of whom 59 (63.4%) were women. The test-retest intraclass correlation coefficient for the seven items was between 0.75 and 0.90 and Cronbach's coefficient of reliability for the HFS-7 scale was 0.88. Every item in HFS-7 discriminated between disease and controls (p<0.0001). The HFS-7 summary index correlated with the SF-36 summary score (Spearman's correlation r = -0.28, p = 0.009), in particular the mental health summary score (r = -0.416, p<0.0001) and the emotional domain (r = -0.466, p<0.00001).

CONCLUSION

HFS-7 could prove useful as a simple clinical tool to assess and monitor QoL measures in HFS patients.

Non-motor manifestations in essential tremor: use of a validated instrument to evaluate a wide spectrum of symptoms

INTRODUCTION

Recent studies suggest an association between non-motor symptoms and essential tremor (ET). Few studies have assessed psychological symptoms in ET. These studies were limited to western white populations and utilized scales that were specific to only one or two psychiatric domains. By contrast, the Symptom Checklist-90R (SCL-90R) is a validated clinical scale to screen for symptoms related to a spectrum of nine different psychological domains.

OBJECTIVE

To determine whether a wide spectrum of non-motor manifestations is associated with ET in patients in an Asian cohort.

METHODS

Consecutive ET patients and a group of control subjects were evaluated using the SCL-90R, which is comprised of items in nine major symptom dimensions and three global indices, including the positive symptom distress index.

RESULTS

ET patients (N = 84) and controls (N = 78) were similar in age (50.0+/-18.0 vs 46.0+/-14.4 years), gender and other demographic variables. ET patients had higher scores in three of nine major symptom dimensions: anxiety, phobic anxiety (p < 0.0005) and psychoticism (p = 0.005). In multivariate analysis, the anxiety (p < 0.0005) and the positive symptom distress index scores (p < 0.0005) were greater in ET patients compared to controls after adjusting for sex, age, marital status and educational level. The severity, but not duration of ET was correlated with the severity of anxiety symptoms.

CONCLUSIONS

Utilizing the SCL-90R, we highlighted that ET patients reported more non-motor symptoms than healthy controls. The more frequent occurrence of anxiety symptoms in our Asian cohort extends the observation that such non-motor manifestations should be considered in the clinical management of ET.

Ventrolateral medullary compression in hypertensive patients with hemifacial spasm

In a patient-controlled study, the authors demonstrated a significantly higher prevalence of rostral ventrolateral medulla (VLM) compression in hypertensive patients with hemifacial spasm (HFS) compared with age-, sex-, race-, disease duration-, and disease severity-matched normotensive patients with HFS (p = 0.02). Hypertensive HFS patients were more likely to have a greater severity of neurovascular compression at the VLM compared with normotensive HFS patients (p = 0.008). VLM compression is associated with risk of hypertension in this study population.

Impaired transcriptional upregulation of Parkin promoter variant under oxidative stress and proteasomal inhibition: clinical association

We provided data to show that the transcriptional activity of wildtype -258T in the parkin promoter region was significantly higher than the -258G variant in human cell lines. The transcriptional activity of wildtype -258T was significantly increased under oxidative stress by hydrogen peroxide, but this was not observed for the -258G variant. The transcriptional upregulation was significantly higher for wildtype -258T compared to -258G variant at 0.1, 0.2 and 0.4 mM of hydrogen peroxide. Similar results were obtained when the cells were treated with a proteasome inhibitor, MG132.Furthermore, in a case control study involving 753 subjects, we demonstrated that the parkin promoter -258G variant was associated with an increased risk of sporadic Parkinson's disease (PD) in the elderly ethnic Chinese population. Our clinical and laboratory data provide corroborative evidence that some older individuals who have the -258G variant may have a higher risk of developing PD.

Differential expression of splice variant and wild-type parkin in sporadic Parkinson's disease

BACKGROUND

Altered splicing of parkin under cellular stress could lead to changes in gene expression and altered protein activity. The causative role of parkin in sporadic Parkinson's disease (PD) is unknown.

OBJECTIVES

We described a parkin splice variant (SV) in the substantia nigra and leukocytes of sporadic PD patients. Using a case control methodology, we investigated the exon 4 SV (E4SV) and wild-type parkin expression in the leukocytes of sporadic PD patients and healthy individuals.

METHODS/RESULTS

We identified a parkin E4SV in the substantia nigra and leukocytes of sporadic PD patients and controls by reverse transcriptase-polymerase chain reaction (PCR). The exon 4 (122 bp) deletion resulted in a reading frame shift over the junction of exons 3-5 and a stop codon (tga) 17 bp downstream from exon 3. The translated truncated protein was associated with a total loss of the two-RING finger functional domain. Utilizing TaqMan real-time PCR with probes located across the junction of exons 3-4 or 3-5, we demonstrated an over-expression of E4SV/wild-type parkin ratio in the leukocytes of sporadic PD patients compared to age-, gender-, and race-matched controls (p<0.0005). A multivariate regression analysis demonstrated that the ratio of E4SV/wild-type parkin expression increased with age in PD patients, but this was not observed in the controls (p<0.0005).

CONCLUSION

The relative expression of E4SV/wild type parkin was increased in sporadic PD compared to healthy controls. Based on our observations, further functional studies to determine the pathophysiologic role of E4SV in sporadic PD patients will be of importance.

Reflex vasoconstrictor responses of the healthy human fingertip skin. Normal range, repeatability, and influencing factors

Skin vasoconstrictor reflexes (SVCRs) are mediated by sympathetic vasoconstrictor nerve fibers and used to test sympathetic function of the extremities. Since there is a dearth of published systematic data on inspiratory gasp-induced SVCR, we studied its range, repeatability, and influencing factors in 64 healthy subjects (mean age 41.9 years, range 20-78 years, 32 males). Mean vasoconstriction for the second digit was 54% (+/-19)/54% (+/-19) (right/left) and 69% (+/-16)/68% (+/-15) for the fourth digit. Forth digit vasoconstriction was significantly larger than the second digit (P < 0.01), but second and fourth digit correlation was good (Pearson: 0.521-0.741). Repeatability using single measure intraclass correlation was good with 0.62/0.69 for the second digit and 0.64/0.80 for the fourth digit (right/left). A trend for decreasing SVCR was seen with increasing age and weight, no effect was seen for gender, height, or blood pressure. The SVCR repeatability and range of variation seen in this study compare favorably with tests of heart rate variability, thermal threshold detection, and motor nerve conduction.

The effect of acupuncture on motor cortex excitability and plasticity

Acupuncture has been used extensively in facilitating motor recovery after stroke. Its mechanism of action remains uncertain. In this sham-controlled study, we demonstrate for the first time that acupuncture has a real and enduring effect on motor cortex functional changes, in terms of cortical excitability and output mapping using transcranial magnetic stimulation.

Behind the facial twitch: depressive symptoms in hemifacial spasm

BACKGROUND

Depression impairs psychosocial and occupational functioning and contributes to significant morbidity and mortality. Hemifacial spasm (HFS) causes social embarrassment and visual and verbal disability.

OBJECTIVE

We examined; (1) the prevalence and predictive factors of depressive symptoms (Becks Depression Inventory (BDI) and clinical assessment) in HFS and (2) the sensitivity and specificity of BDI as a screening and diagnostic tool in HFS.

METHODS

A large cohort of HFS patients in a movement disorders clinic was clinically evaluated and the BDI self-administered by patients. Univariate analysis and multivariate logistic regression were undertaken to investigate the effect of age, gender, body-mass index, duration and severity of HFS on the outcome of BDI score. ROC (receiver operating characteristics) analysis was utilized to evaluate the sensitivity and specificity and discriminative property of the scale.

RESULTS

There were 90 HFS patients with a mean age of 54.4+11.1 (35-79) years, comprising of 58.9% women and with a mean severity HFS score of 2.9+0.8 (range 1-4). The mean BDI score was higher in depressed HFS than in non-depressed HFS (19.7+6.7 vs 4.2+4.9, p<0.0001). Female gender and a younger age were risk factors (p=0.07). In the multivariate analysis, the severity of HFS was an independent predictor of BDI scores (p<0.0001). The AUC was 97.1% suggesting excellent discriminative property of BDI. For cut-off score of 12/13, the sensitivity was 93.3%, specificity 94.7%, Positive Predictive Value 77.8% and Negative Predictive Value 98.6%.

CONCLUSIONS

The prevalence of depressive disorder in HFS was 16.7%, with younger women at greater risk. The severity of HFS was positively correlated with the severity of depressive symptoms. The BDI can be a complimentary screening and/or diagnostic instrument for depressive disorder in HFS. Early diagnosis of at-risk patients will prevent unnecessary morbidity and mortality.