The clinical use of drugs influencing neurotransmitters in the brain to promote motor recovery after stroke; a Cochrane systematic review\ud

The objective of this review was to compare and to discuss the results of studies that investigated the ability of drugs to improve motor recovery after stroke by influencing dopamine, norepinephrine, or serotonin concentrations in the brain. A systematic literature search up to January 2009 was conducted in MEDLINE, Pubmed, EMBASE and in the database of the Cochrane Stroke Group Trial Register. In addition, the literature reference lists of the relevant publications were checked. The literature search was conducted in order to identify randomized controlled trials focusing on the effects of drugs on motor recovery after stroke. In order to structure the data, motor recovery was sub-divided into motor control and motor function. The methodological quality of the studies was also assessed. Six studies, investigating the effects of 7 different kinds of drugs were included. Methodological scores varied between 10 and 14 (max 19). Motor control was not influenced by any of the drugs. Motor function improved in patients treated with methylphenidate, trazodone, and nortriptyline. Results for fluoxetine and levodopa were contradicting. There is insufficient evidence to conclude that neuromodulating drugs targeting serotonin, norepinephrine, or dopamine influence motor recovery after strok

Fluoxetine and motor imagination to facilitate recovery after ischemic stroke

Plasticity of the brain is thought to play a crucial role in the recovery of motor function after stroke. The main objective of this thesis is to examine the possibility to facilitate the recovery of motor function by investigating (1) the use of psychoactive agents affecting the concentration of neurotransmitters in the brain, and (2) the use of movement imagination.\ud \ud 1. Studies examining the effects of pharmacological interventions show contradicting results since many confounders influence the effects of the psychoactive agents on motor function. We examined the impact of fluoxetine on motor function, and related these outcomes to changes in muscle activity and brain activity. By doing so more insight was obtained in the potential of fluoxetine to affect cortical processes improving the recovery of motor function after stroke.\ud \ud After administration of a single dose of fluoxetine 20 mg in chronic stroke patients an increased muscle activity was found in the paretic arm in both agonistic and antagonistic muscles. A significantly larger brain activity was found in the affected (ipsilateral) hemisphere during execution of the movement by the healthy hand. We found no significant relation between these changes. \ud \ud 2. Other interventions possibly facilitating neuroplasticity are observation and imagination of a movement. A significantly larger modification of the cortical activity was found during the combination of observation and imagination compared to observation-only in healthy subjects, during the whole period of imagination. This suggests an additive effect of imagination to observation.\ud In stroke patients, the motor cortex was found to be activated during imagination. However, the activity of the motor cortex was significantly higher during execution compared to imagination of the movement.\ud \ud The interaction between both therapies was studied as well. Fluoxetine was found to significantly increase the cortical activity related to movement in the non-affected motor cortex during the execution of the movement. During imagination of the movement trends were found indicating the same effect of fluoxetine.\ud \ud The results described in this thesis on the effects of fluoxetine and imagination on the recovery of motor function are very promising and give clear leads for continuation of this line of research

Differential cortical activation during observation and observation-and-imagination

The activity of the brain during observation or imagination of movements might facilitate the relearning of motor functions after stroke. The present study examines whether there is an additional effect of imagination over observation-only. Eight healthy subjects observed and observed-and-imagined a movement of a hand; 64-channel EEG was used to measure brain activity. The synchronization of the theta (4–8 Hz), alpha (8–13 Hz) and beta (13–25 Hz) frequency bands was calculated and plotted in topoplots. The temporal changes of the sensorimotor area (C3, C4) and the centro-parietal cortex (Pz) were analyzed in the two experimental conditions. During observation-and-imagination, a significant larger desynchronization (p = 0.004) in the sensorimotor area was found compared to observation-only in all electrodes and frequency bands. In addition, temporal differences were found between observation and observation-and-imagination in the alpha frequency bands. During observation-and-imagination, modulations of EEG rhythms were stronger than during observation-only in the theta, alpha and beta frequency bands and during almost the whole activity fragment. These findings suggest an additive effect of imagination to observation in the rehabilitation after stroke

Body mass index and complications following major gastrointestinal surgery: A prospective, international cohort study and meta-analysis

Aim Previous studies reported conflicting evidence on the effects of obesity on outcomes after gastrointestinal surgery. The aims of this study were to explore the relationship of obesity with major postoperative complications in an international cohort and to present a metaanalysis of all available prospective data. Methods This prospective, multicentre study included adults undergoing both elective and emergency gastrointestinal resection, reversal of stoma or formation of stoma. The primary end-point was 30-day major complications (Clavien–Dindo Grades III–V). A systematic search was undertaken for studies assessing the relationship between obesity and major complications after gastrointestinal surgery. Individual patient meta-analysis was used to analyse pooled results. Results This study included 2519 patients across 127 centres, of whom 560 (22.2%) were obese. Unadjusted major complication rates were lower in obese vs normal weight patients (13.0% vs 16.2%, respectively), but this did not reach statistical significance (P = 0.863) on multivariate analysis for patients having surgery for either malignant or benign conditions. Individual patient meta-analysis demonstrated that obese patients undergoing surgery formalignancy were at increased risk of major complications (OR 2.10, 95% CI 1.49–2.96, P < 0.001), whereas obese patients undergoing surgery for benign indications were at decreased risk (OR 0.59, 95% CI 0.46–0.75, P < 0.001) compared to normal weight patients. Conclusions In our international data, obesity was not found to be associated with major complications following gastrointestinal surgery. Meta-analysis of available prospective data made a novel finding of obesity being associated with different outcomes depending on whether patients were undergoing surgery for benign or malignant disease