Efficacy of cabergoline in restless legs syndrome: A placebo-controlled study with polysomnography (CATOR)

OBJECTIVE

To assess the efficacy and safety of the dopamine agonist cabergoline in the treatment of patients with idiopathic restless legs syndrome (CATOR study).

METHODS

Patients with moderate to severe restless legs syndrome (RLS) were randomly assigned to cabergoline (single evening dose: 2 mg) or placebo and treated for 5 weeks in a double-blind, multicenter polysomnography (PSG) trial. The primary efficacy measures were the periodic leg movements during sleep arousal index (PLMS-AI) and sleep efficiency. These and further PSG variables were monitored by centrally evaluated PSG. Severity of RLS was assessed using the International RLS Study Group Severity Scale (IRLS), the RLS-6 scales, the Sleep Questionnaire Form A (SF-A; quality of sleep), and the Quality of Life for RLS questionnaire.

RESULTS

Forty-three patients were treated and 40 patients were evaluated with PSG (age 56 +/- 10 years, 73% women). Cabergoline was superior to placebo in terms of the PLMS-AI (-17.7 +/- 16.4 vs -4.5 +/- 20.0 placebo; p = 0.0024), sleep efficiency (+6.2 +/- 13.9% vs +3.3 +/- 11.7%; p = 0.0443), PLMS index (p = 0.0014), PLM index (p = 0.0012), and total sleep time (p = 0.0443). Improvements in IRLS total score (-23.7 +/- 11.2 vs -7.9 +/- 11.0 placebo; p = 0.0002), RLS-6 severity scales during the night (p = 0.0010) and during the day (p = 0.0018), Clinical Global Impressions severity item (p = 0.0003), sleep quality (p = 0.0180), SF-A sleep quality (p = 0.0371), and QoL-RLS (p = 0.0247) were larger in patients treated with cabergoline compared with the placebo group. Adverse events were only mild and well-known side effects of dopamine agonists.

CONCLUSION

Single-evening cabergoline is an efficacious and well-tolerated short-term therapy for sensorimotor symptoms of restless legs syndrome and associated sleep disturbances.

Effective cabergoline treatment in idiopathic restless legs syndrome

OBJECTIVE

To assess the efficacy and safety of the dopamine agonist cabergoline (CAB) in patients with restless legs syndrome (RLS).

METHODS

Patients with moderate to severe RLS were randomized into four groups receiving placebo, 0.5 mg, 1 mg, or 2 mg CAB once daily in a double-blind, placebo-controlled, multicenter dose-finding trial followed by an open long-term extension trial of 47 weeks. Efficacy was assessed with the RLS-6 scales and International RLS Study Group severity scale (IRLS).

RESULTS

A total of 85 patients (age 56 +/- 10 years, 71% females) were treated. Severity of RLS-6 scale symptoms during the night (the primary endpoint) was markedly improved by all CAB doses compared to placebo (placebo: -1.4 +/- 3.1, 0.5 mg CAB: -4.2 +/- 3.0 [p = 0.0082], 1.0 mg CAB: -4.0 +/- 2.9 [p = 0.0040], 2.0 mg CAB: -4.8 +/- 3.7 [p = 0.0026]). Similar results were found for the RLS severity at bedtime and during the day, IRLS, and satisfaction with sleep. A stable, clinically relevant improvement was achieved in all efficacy measures (severity during the night: change between last assessment and baseline: -5.6 +/- 2.5, rate of remission: 71.2%) throughout 1 year with a mean CAB dose of 2.2 mg per day. During long-term treatment, 6 of 66 treated patients were affected (n = 2) or possibly affected (n = 4) by mild augmentation. Under CAB therapy up to 1 year, 11 of 85 patients discontinued treatment due to a drug-related adverse event.

CONCLUSIONS

Cabergoline is an efficacious and well-tolerated option for the treatment of restless legs symptoms during the night and the day.

Simplified models of flue instruments: influence of mouth geometry on the sound source

Flue instruments such as the recorder flute and the transverse flute have different mouth geometries and acoustical response. The effect of the mouth geometry is studied by considering the aeroacoustical response of a simple whistle. The labium of a transverse flute has a large edge angle (60 degrees) compared to that of a recorder flute (15 degrees). Furthermore, the ratio W/h of the mouth width W to the jet thickness h can be varied in the transverse flute (lips of the musician) while it is fixed to a value W/h approximately 4 in a recorder flute. A systematic experimental study of the steady oscillation behavior has been carried out. Results of acoustical pressure measurements and flow visualization are presented. The sharp edge of the recorder provides a sound source which is rich in harmonics at the cost of stability. The larger angle of the labium of the flute seems to be motivated by a better stability of the oscillations for thick jets but could also be motivated by a reduction of broadband turbulence noise. We propose two simplified sound source models which could be used for sound synthesis: a jet-drive model for W/h>2 and a discrete-vortex model for W/h<2.

Multicenter evaluation of the Glucometer Elite XL meter, an instrument specifically designed for use with neonates

OBJECTIVE

To evaluate the clinical performance of the Glucometer Elite XL Diabetes Care System in neonatal settings using a multicenter study

RESEARCH DESIGN AND METHODS

A total of 388 blood specimens from 333 neonates were included in the study. A capillary or arterial sample was analyzed for determination of glucose with the Glucometer Elite XL system by an attending trained nurse. Through the same sampling site, a specimen was collected and sent to the laboratory for measurement of plasma glucose, bilirubin, and hematocrit.

RESULTS

The regression analysis between the results of the Glucometer Elite XL system and comparative methods resulted in the following: Glucometer Elite XL meter = 1.01 x laboratory method + 0.02 mmol/l (n = 388). For the 1.1-4.0 mmol/l plasma glucose range, the regression was Glucometer Elite XL meter = 1.07 x laboratory method + 0.12 mmol/l (n = 150). A difference plot indicated a mean bias of 0.04 mmol/l (95% CI -0.01 to 0.10). No relationship was found between meter glucose biases and hematocrit levels (r = 0.10, P = 0.14). Although a statistically significant correlation existed between bilirubin levels and the glucose meter biases (r = 0.14, P = 0.005), the predicted mean biases were of little clinical significance.

CONCLUSIONS

The Glucometer Elite XL system showed a good performance when used in neonatal settings.

Effect of point of care testing on length of stay in an adult emergency department

Devices are now available that are practical for point of care testing (PCT) in hospital settings. Previous studies in clinical settings, however, have failed to demonstrate a reduction in patients' length of stay (LOS) associated with the use of PCT. This randomized controlled study compared PCT with central laboratory testing in a hospital Emergency Department to assess the difference in patients' LOS. Patients randomized to PCT (n = 93) had a median stay of 3 h, 28 min (interquartile range [IR] 2:28 to 5:30), while those allocated to the central laboratory (n = 87) had a median stay of 4 h, 22 min (IR 3:04 to 5:47). The median stay associated with PCT was significantly shorter. Among patients who were destined to be discharged home, there was also a significantly shorter stay, but not among those who were destined to be admitted. It was concluded that the use of PCT can achieve significant time savings in an Emergency Department.

[An anatomic study of the superficial radial nerve and its clinical implications]

In hand surgery, the k-wires are used frequently and effectively. Several texts mention complications following surgery of the wrist and hand. A safe zone has been described by Steinberg et al., where 40 K-wires were placed in the anatomic snuffbox of 10 cadaveric forearms. The placement of the k-wires were evaluated radiologically and by dissection to examine the underlying structures. A branch of the superficial radial nerve (NRS) was injured in 22% (2/9) of the specimens and the cephalic vein in 33% (3/9). The radial artery was never injured but had a K-wires at least 1 mm away in 22% of the specimens. The anatomy and pattern of distribution of the NRS was studied and compared with the data found in the literature. The NRS emerged between the tendons the muscles of brachioradialis and extensor carpi radialis longus in 9 of 10 specimens, and at a mean distance of 7.8 cm from the radial styloid. The first and second division were at a mean distance proximal to the radial styloid of 4.5 and 3.0 cm, respectively. The mean number of branches of the NRS at the radial styloid was 5.1. Despite a relatively consistent anatomy of the NRS, the anatomic snuffbox remains a complex and dangerous area due to the variability of the nerve's anatomy. An open surgical approach is thus preferred to avoid traumatizing the nerves and vascular structures.

[Biomechanical evaluation and clinical correlation of 3 methods of internal fixation of metacarpophalangeal arthrodesis of the thumb]

Three methods of internal fixation for MCP arthrodesis of fifteen cadaveric thumbs were used to analyze the biomechanical stability by applying a palmar force, lateral force, and torsion moment. The techniques used included two K-wires 0.045 in parallel (BK), 2 cerclage metallic wires #25 perpendicular to each other (CP), and a 6-holes plate and screws construct from Synthes (PV). The initial rigidity was measured using a Bionix MTS-858. The results after statistical analysis showed: 1) CP was just as rigid as PV for the palmar and lateral tests; 2) CP was, overall, superior to BK in palmar and lateral tests; 3) no difference existed in torsion between the three types of fixation. A comparison was done between the rigidity of the fixation techniques used and the rates of bony nonunion found in the literature. The mean rates of nonunion were reported to be 0-4.0% for the following techniques: CP, tension band wiring (TB), plate and screws, external fixation, compression screw. The rates of nonunion were higher, 7.5-12.5%, for BK, cerclages not perpendicular (CM), bone pegs. According to the results of this biomechanical study and the review of the literature, fixation with BK is the least rigid, and fixation with CP is just as rigid as with PV. The success clinically of CP is yet to be demonstrated. Other studies on the properties of CP for fatigue would be necessary to give a better analysis.

Multianalyte serum analysis using mid-infrared spectroscopy

This study assesses the potential for using mid-infrared (mid-IR) spectroscopy of dried serum films as the basis for the simultaneous quantitation of eight serum analytes: total protein, albumin, triglycerides, cholesterol, glucose, urea, creatinine and uric acid. Infrared transmission spectra were acquired for 300 serum samples, each analysed independently using accepted reference clinical chemical methods. Quantitation methods were based upon the infrared spectra and reference analyses for 200 specimens, and the models validated using the remaining 100 samples. Standard errors in the IR-predicted analyte levels (Sy/x) were 2.8 g/L (total protein), 2.2 g/L (albumin), 0.23 mmol/L (triglycerides), 0.28 mmol/L (cholesterol), 0.41 mmol/L (glucose) and 1.1 mmol/L for urea, with correlation coefficients (IR vs reference analyses) of 0.95 or better. The IR method emerged to be less suited for creatinine (Sy/x = mumol/L) and uric acid (Sy/x = 140 mumol/L) due to the relatively low concentrations typical of these analytes.

Three-dimensional joint moments analysis in a vertical quadrupedal posture associated with a leg release

This study reports on rock climbers biomechanical adjustments following a leg release from a quadrupedal vertical initial stance. Six climbers of international level have been studied. They were asked to maintain a quadrupedal posture on artificial holds equipped with strain gauges and then to release their right foot. The results show that all the rock climbers adjust differently the vertical forces and the horizontal forces on the holds. They distribute the vertical forces over the three remaining holds and the horizontal forces over the controlateral holds. A quasi-static three-dimensional multi-segment model was used to produce the net reaction forces and joint moments at each joint. Moment results enhance the role of the controlateral limbs, particularly the left leg. The gravity seems to be counteracted at the left knee joint, while body balance seems to be managed at the left hip and ankle joints.

Quantitation of protein, creatinine, and urea in urine by near-infrared spectroscopy

OBJECTIVES

To determine the feasibility of near-infrared analysis for quantitating urea, creatinine, and protein in urine. Practical advantages of this method include ease of sample presentation and the absence of reagents or disposables.

DESIGN AND METHODS

The near-infrared methods were developed by first measuring the spectra of 123 different urine samples and, using independent clinical analyses, determining the protein, creatinine, and urea levels in each. Calibration models relating near-infrared spectroscopic features to those independently determined concentrations were optimized, and each model then validated using a set of 50 additional samples.

RESULTS

Standard errors of calibration were 14.4 mmol/L, 0.66 mmol/L, and 0.20 g/L, and standard errors of prediction 16.6 mmol/L, 0.79 mmol/L, and 0.23 g/L, respectively, for urea, creatinine, and protein.

CONCLUSIONS

Near-infrared urea quantitation is as accurate as the reference method, enzymatic (urease) conductivity, used here for calibration. Creatinine analysis is slightly less accurate relative to the reference (Jaffe rate) method; however, these errors can be minimized by careful attention to factors affecting precision. The accuracy of the near-infrared protein analysis cannot approach that of the reference method; nevertheless, the technique is potentially useful for coarse screening and for quantifying protein levels above 0.3 g/L.

Effect of initial posture on biomechanical adjustments associated with a voluntary leg movement in rock climbers

This study compares the biomechanical adjustments following a leg displacement in vertical and horizontal position on expert rock climbers. The results show a non-diagonal pattern in the vertical condition and a diagonal one in the horizontal condition. A multi-link analysis shows that the non-diagonal pattern displayed by expert climbers in the vertical condition resulted in a new distribution of body weight to preserve the possibility of moving any limb from the three legged stance. Conversely, in the horizontal condition, the diagonal pattern appears to be strongly dominated by mechanical and anthropometric factors.