Escitalopram and enhancement of cognitive recovery following stroke

Post stroke use of selective serotonin reuptake inhibitors and clinical outcome among patients with ischemic stroke: a nationwide propensity score-matched follow-up study

BACKGROUND AND PURPOSE

Selective serotonin reuptake inhibitors (SSRIs) are widely prescribed after stroke. We aimed to investigate whether potential antiplatelet or vasospastic effects have important clinical implications.

METHODS

Using data from Danish medical registries, we did a nationwide follow-up study among ischemic stroke patients between 2003 and 2009. We identified 5833 SSRI users, and propensity score matched these patients with nonusers in a 1:1 ratio, followed by Cox regression analysis to compute hazard ratios (HRs) of acute myocardial infarction, recurrent stroke, major bleeding, and death.

RESULTS

Median follow-up time (from 30 days after discharge to death/end of follow-up) was 1159 days. In total, 2.9% had myocardial infarction, 8.1% recurrent ischemic stroke, 20.2% major bleeding, 1.4% intracranial bleeding, and 34.4% died during follow-up. SSRI users had a lower risk of the combined outcome of myocardial infarction or recurrent ischemic stroke (adjusted HR, 0.77; confidence interval [CI], 0.62-0.96). However, the SSRI users also experienced a higher risk of overall major bleeding (adjusted HR, 1.33; CI, 1.14-1.55) and a nonsignificantly higher risk of intracranial bleedings (adjusted HR, 1.14; CI, 0.62-2.12). Mortality increased in SSRI users (adjusted HR, 1.13; CI, 1.00-1.28) and death caused by bleeding increased (adjusted HR, 1.89; CI, 0.97-3.66) as compared with death by other causes (adjusted HR, 1.11; CI; 0.98-1.26).

CONCLUSIONS

SSRI use after ischemic stroke was associated with a lower risk of new cardiovascular events and also with an increased bleeding risk. There was an increased mortality among SSRI users, which may be related to the increased bleeding risk.

Post-stroke depression: mechanisms, translation and therapy

The interaction between depression and stroke is highly complex. Post-stroke depression (PSD) is among the most frequent neuropsychiatric consequences of stroke. Depression also negatively impacts stroke outcome with increased morbidity, mortality and poorer functional recovery. Antidepressants such as the commonly prescribed selective serotonin reuptake inhibitors improve stroke outcome, an effect that may extend far beyond depression, e.g., to motor recovery. The main biological theory of PSD is the amine hypothesis. Conceivably, ischaemic lesions interrupt the projections ascending from midbrain and brainstem, leading to a decreased bioavailability of the biogenic amines – serotonin (5HT), dopamine (DA) and norepinephrine (NE). Acetylcholine would also be involved. So far, preclinical and translational research on PSD is largely lacking. The implementation and characterization of suitable animal models is clearly a major prerequisite for deeper insights into the biological basis of post-stroke mood disturbances. Equally importantly, experimental models may also pave the way for the discovery of novel therapeutic targets. If we cannot prevent stroke, we shall try to limit its long-term consequences. This review therefore presents animal models of PSD and summarizes potential underlying mechanisms including genomic signatures, neurotransmitter and neurotrophin signalling, hippocampal neurogenesis, cellular plasticity in the ischaemic lesion, secondary degenerative changes, activation of the hypothalamo-pituitary-adrenal (HPA) axis and neuroinflammation. As stroke is a disease of the elderly, great clinical benefit may especially accrue from deciphering and targeting basic mechanisms underlying PSD in aged animals.

Treatment of neurodevelopmental disorders in adulthood

Brain development in neurodevelopmental disorders has been considered to comprise a sequence of critical periods, and abnormalities occurring during early development have been considered irreversible in adulthood. However, findings in mouse models of neurodevelopmental disorders, including fragile X, Rett syndrome, Down syndrome, and neurofibromatosis type I suggest that it is possible to reverse certain molecular, electrophysiological, and behavioral deficits associated with these disorders in adults by genetic or pharmacological manipulations. Furthermore, recent studies have suggested that critical period-like plasticity can be reactivated in the adult brain by environmental manipulations or by pharmacotherapy. These studies open up a tantalizing possibility that targeted pharmacological treatments in combination with regimes of training or rehabilitation might alleviate or reverse the symptoms of neurodevelopmental disorders even after the end of critical developmental periods. Even though translation from animal experimentation to clinical practice is challenging, these results suggest a rational basis for treatment of neurodevelopmental disorders in adulthood.

Stroke rehabilitation: recent advances and future therapies

Despite advances in the acute management of stroke, a large proportion of stroke patients are left with significant impairments. Over the coming decades the prevalence of stroke-related disability is expected to increase worldwide and this will impact greatly on families, healthcare systems and economies. Effective neuro-rehabilitation is a key factor in reducing disability after stroke. In this review, we discuss the effects of stroke, principles of stroke rehabilitative care and predictors of recovery. We also discuss novel therapies in stroke rehabilitation, including non-invasive brain stimulation, robotics and pharmacological augmentation. Many trials are currently underway, which, in time, may impact on future rehabilitative practice.

Selective serotonin reuptake inhibitors (SSRIs) for stroke recovery

BACKGROUND

Stroke is the major cause of adult disability. Selective serotonin reuptake inhibitors (SSRIs) have been used for many years to manage depression. Recently, small trials have demonstrated that SSRIs might improve recovery after stroke, even in people who are not depressed. Systematic reviews and meta-analyses are the least biased way to bring together data from several trials. Given the promising effect of SSRIs on stroke recovery seen in small trials, a systematic review and meta-analysis is needed.

OBJECTIVES

To determine whether SSRIs improve recovery after stroke, and whether treatment with SSRIs was associated with adverse effects.

SEARCH METHODS

We searched the Cochrane Stroke Group Trials Register (August 2011), Cochrane Depression Anxiety and Neurosis Group Trials Register (November 2011), Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2011, Issue 8), MEDLINE (from 1948 to August 2011), EMBASE (from 1980 to August 2011), CINAHL (from 1982 to August 2011), AMED (Allied and Complementary Medicine) (from 1985 to August 2011), PsycINFO (from 1967 to August 2011) and PsycBITE (Pyschological Database for Brain Impairment Treatment Efficacy) (March 2012). To identify further published, unpublished and ongoing trials we searched trials registers, pharmaceutical websites, reference lists, contacted experts and performed citation tracking of included studies.

SELECTION CRITERIA

We included randomised controlled trials that recruited stroke survivors (ischaemic or haemorrhagic) at any time within the first year. The intervention was any SSRI, given at any dose, for any period. We excluded drugs with mixed pharmacological effects. The comparator was usual care or placebo. In order to be included, trials had to collect data on at least one of our primary (dependence and disability) or secondary (impairments, depression, anxiety, quality of life, fatigue, healthcare cost, death, adverse events and leaving the trial early) outcomes.

DATA COLLECTION AND ANALYSIS

We extracted data on demographics, type of stroke, time since stroke, our primary and secondary outcomes, and sources of bias. For trials in English, two review authors independently extracted data. For Chinese papers, one review author extracted data. We used standardised mean differences (SMD) to estimate treatment effects for continuous variables, and risk ratios (RR) for dichotomous effects, with their 95% confidence intervals (CIs).

MAIN RESULTS

We identified 56 completed trials of SSRI versus control, of which 52 trials (4059 participants) provided data for meta-analysis. There were statistically significant benefits of SSRI on both of the primary outcomes: RR for reducing dependency at the end of treatment was 0.81 (95% CI 0.68 to 0.97) based on one trial, and for disability score, the SMD was 0.91 (95% CI 0.60 to 1.22) (22 trials involving 1343 participants) with high heterogeneity between trials (I(2) = 87%; P < 0.0001). For neurological deficit, depression and anxiety, there were statistically significant benefits of SSRIs. For neurological deficit score, the SMD was -1.00 (95% CI -1.26 to -0.75) (29 trials involving 2011 participants) with high heterogeneity between trials (I(2) = 86%; P < 0.00001). For dichotomous depression scores, the RR was 0.43 (95% CI 0.24 to 0.77) (eight trials involving 771 participants) with high heterogeneity between trials (I(2) = 77%; P < 0.0001). For continuous depression scores, the SMD was -1.91 (95% CI -2.34 to -1.48) (39 trials involving 2728 participants) with high heterogeneity between trials (I(2) = 95%; P < 0.00001). For anxiety, the SMD was -0.77 (95% CI -1.52 to -0.02) (eight trials involving 413 participants) with high heterogeneity between trials (I(2) = 92%; P < 0.00001). There was no statistically significant benefit of SSRI on cognition, death, motor deficits and leaving the trial early. For cognition, the SMD was 0.32 (95% CI -0.23 to 0.86), (seven trials involving 425 participants) with high heterogeneity between trials (I(2) = 86%; P < 0.00001). The RR for death was 0.76 (95% CI 0.34 to 1.70) (46 trials involving 3344 participants) with no heterogeneity between trials (I(2) = 0%; P = 0.85). For motor deficits, the SMD was -0.33 (95% CI -1.22 to 0.56) (two trials involving 145 participants). The RR for leaving the trial early was 1.02 (95% CI 0.86 to 1.21) in favour of control, with no heterogeneity between trials. There was a non-significant excess of seizures (RR 2.67; 95% CI 0.61 to 11.63) (seven trials involving 444 participants), a non-significant excess of gastrointestinal side effects (RR 1.90; 95% CI 0.94 to 3.85) (14 trials involving 902 participants) and a non-significant excess of bleeding (RR 1.63; 95% CI 0.20 to 13.05) (two trials involving 249 participants) in those allocated SSRIs. Data were not available on quality of life, fatigue or healthcare costs.There was no clear evidence from subgroup analyses that one SSRI was consistently superior to another, or that time since stroke or depression at baseline had a major influence on effect sizes. Sensitivity analyses suggested that effect sizes were smaller when we excluded trials at high or unclear risk of bias.Only eight trials provided data on outcomes after treatment had been completed; the effect sizes were generally in favour of SSRIs but CIs were wide.

AUTHORS' CONCLUSIONS

SSRIs appeared to improve dependence, disability, neurological impairment, anxiety and depression after stroke, but there was heterogeneity between trials and methodological limitations in a substantial proportion of the trials. Large, well-designed trials are now needed to determine whether SSRIs should be given routinely to patients with stroke.

A critical review of the mechanism of action for the selective serotonin reuptake inhibitors: do these drugs possess anti-inflammatory properties and how relevant is this in the treatment of depression?

The selective serotonin reuptake inhibitors (SSRIs) are the most widely prescribed pharmacological treatment for depression. Since their introduction many have considered the primary mechanism by which the SSRIs produced therapeutic improvement in depression is their effect on monoaminergic signalling. In recent years, however, the credibility of the monoamine theory and the therapeutic efficacy of these compounds in the treatment of depression has been extensively criticized. In the current review the legitimacy of these criticisms is critically examined, in many instances the evidence base used to support these criticisms is found to be weak. Nevertheless, the apparent 'failure' of the monoamine theory has been of benefit in motivating research into alternative mechanisms through which the SSRIs may act. Given research demonstrating that depressive symptoms are intimately linked with disturbances in pro-inflammatory signalling, perhaps the most promising discovery has been the realisation that SSRIs posses significant anti-inflammatory properties. These recent findings are discussed and contextualised with respect to the neurogenic, neurotrophic and gluatamatergic effects that these drugs also possess.

Association among depression, cognitive impairment and executive dysfunction after stroke

The relationship between depression and cognitive impairment, frequent after stroke, is complex and has not been sufficiently elucidated.

Post-stroke depression: an update

INTRODUCTION

Post-stroke depression (PSD) is the most common mood disorder following a stroke, and also the main factor limiting recovery and rehabilitation in stroke patients. In addition, it may increase mortality by up to ten times.

DEVELOPMENT

PSD occurs in 1 in 3 stroke patients and more than half of all cases are neither diagnosed nor treated. Several mechanisms, including biological, behavioral, and social factors, are involved in its pathogenesis. Symptoms usually occur within the first three months after stroke (early onset PSD), and less frequently at a later time (late onset PSD). Symptoms resemble those of other types of depression, although there are some differences: PSD patients experience more sleep disturbances, vegetative symptoms, and social withdrawal. For PSD diagnosis, we recommended vigilance and use of specific diagnostic tools such as the Patient Health Questionnaire-2 (PHQ-2). The treatments of choice are selective serotonin reuptake inhibitors (SSRI). However, there are still many unanswered questions in the treatment of PSD, such as the best time to start treatment or the effects of antidepressants on cognition and motor function, among others.

CONCLUSIONS

Neurologists play a pivotal role in the care and management of patients recovering from stroke. They must be familiar with methods for early detection and treatment of PSD, as this can facilitate a patient's functional recovery and social reintegration, and improve quality of life for patients and their families.

Exofocal dopaminergic degeneration as antidepressant target in mouse model of poststroke depression

BACKGROUND

Although poststroke depression (PSD) is a frequent chronic complication of stroke with high relevance for outcome and survival, underlying pathomechanisms remain inadequately understood. This may be because suitable animal models are largely lacking and existing models are poorly characterized.

METHODS

Male 129/SV mice were subjected to 30-min middle cerebral artery occlusion (MCAo)/reperfusion and serial magnetic resonance imaging scans. A subset of animals received selective serotonin reuptake inhibitor citalopram starting 7 days after MCAo. Behavioral assessment was performed at 14 weeks. To identify biological correlates of PSD, we quantified corticosterone levels in serum and brain-derived neurotrophic factor levels in brain. The integrity of the mesolimbic dopaminergic system was assessed using tyrosine hydroxylase and dynorphin in situ hybridizations as well as dopamine transporter autoradiography.

RESULTS

Left, but not right, MCAo, elicited anhedonia and increased anxiety and despair. This depression-like syndrome was associated with alterations in the mesolimbic reward system. MCAo resulted in delayed degeneration of dopaminergic neurons in ipsilateral midbrain, which was accompanied by reduced dopamine concentrations and decreased levels of dopamine transporter density along with increased brain-derived neurotrophic factor protein levels in ischemic striatum and increased dynorphin messenger RNA expression in nucleus accumbens. Chronic antidepressant treatment initiated as late as 7 days after stroke reversed the behavioral phenotype, prevented degeneration of dopaminergic midbrain neurons, and attenuated striatal atrophy at 4 months.

CONCLUSIONS

Our results highlight the importance of the dopaminergic system for the development of PSD. Prevention of secondary neurodegeneration by antidepressants may provide a novel target for subacute stroke therapy.

Depression, strokes and dementia: new biological insights into an unfortunate pathway

The literature emphasizes the risk of depression after a stroke. Less well known is the fact that depression may be as big a risk factor for strokes as hypertension, particularly in the older age group. This article reviews the risk for stroke and cognitive impairment consequent to depression, and describes the cardiovascular and immunological mechanisms that would appear to link depression to its cerebrovascular consequences. As well, the article refers to the brain imaging signatures that may allow prediction of impending brain injury. Finally, some questions that might be explored by future research are suggested, and some practical means to identify and help those at risk for the development of depression-associated vascular disease of the brain are suggested.

A phase I study of low-pressure hyperbaric oxygen therapy for blast-induced post-concussion syndrome and post-traumatic stress disorder

This is a preliminary report on the safety and efficacy of 1.5 ATA hyperbaric oxygen therapy (HBOT) in military subjects with chronic blast-induced mild to moderate traumatic brain injury (TBI)/post-concussion syndrome (PCS) and post-traumatic stress disorder (PTSD). Sixteen military subjects received 40 1.5 ATA/60 min HBOT sessions in 30 days. Symptoms, physical and neurological exams, SPECT brain imaging, and neuropsychological and psychological testing were completed before and within 1 week after treatment. Subjects experienced reversible middle ear barotrauma (5), transient deterioration in symptoms (4), and reversible bronchospasm (1); one subject withdrew. Post-treatment testing demonstrated significant improvement in: symptoms, neurological exam, full-scale IQ (+14.8 points; p<0.001), WMS IV Delayed Memory (p=0.026), WMS-IV Working Memory (p=0.003), Stroop Test (p<0.001), TOVA Impulsivity (p=0.041), TOVA Variability (p=0.045), Grooved Pegboard (p=0.028), PCS symptoms (Rivermead PCSQ: p=0.0002), PTSD symptoms (PCL-M: p<0.001), depression (PHQ-9: p<0.001), anxiety (GAD-7: p=0.007), quality of life (MPQoL: p=0.003), and self-report of percent of normal (p<0.001), SPECT coefficient of variation in all white matter and some gray matter ROIs after the first HBOT, and in half of white matter ROIs after 40 HBOT sessions, and SPECT statistical parametric mapping analysis (diffuse improvements in regional cerebral blood flow after 1 and 40 HBOT sessions). Forty 1.5 ATA HBOT sessions in 1 month was safe in a military cohort with chronic blast-induced PCS and PTSD. Significant improvements occurred in symptoms, abnormal physical exam findings, cognitive testing, and quality-of-life measurements, with concomitant significant improvements in SPECT.

Increased frequency of first-episode poststroke depression after discontinuation of escitalopram

BACKGROUND AND PURPOSE

The purpose of this study was to compare escitalopram, problem-solving therapy, and placebo to prevent poststroke depression during 6 months after discontinuation of treatment.

METHODS

We examined for depression 33 patients assigned to placebo, 34 to escitalopram, and 41 to problem-solving therapy.

RESULTS

After controlling for age, gender, prior mood disorder, and severity of stroke, new-onset major depression and Hamilton Depression scores were significantly higher 6 months after escitalopram was discontinued compared with the problem-solving therapy or placebo groups.

CONCLUSIONS

Discontinuation of escitalopram may increase poststroke depressive symptoms.

Listening to Fluoxetine: A Hot Message from the FLAME Trial of Poststroke Motor Recovery

The fluoxetine for motor recovery after acute ischemic stroke study was a double blind, placebo-controlled trial examining the effects of fluoxetine in patients five- to 10 days after an ischemic stroke. The study found motor improvement to 90 days poststroke, measured as the change in the Fugl–Meyer score, was significantly greater in the fluoxetine group as compared with the placebo group, and that this finding was significant after adjusting for depression. Patients randomized to fluoxetine also had less disability (modified Rankin Scale 0–2). The study adds to the weight of data suggesting that viable strategies exist to improve patient outcomes by initiating a restorative agent, days after stroke injury is fixed. Stroke remains among the leading causes of human disability. Currently, a minority of patients can access approved reperfusion therapies, and among those so treated a substantial fraction derives limited benefit. Therapies that target restorative events have a time window measured in days–weeks and so hold the potential to help many patients with stroke.

Vascular cognitive impairment: disease mechanisms and therapeutic implications

The prevalence of vascular cognitive impairment (VCI) is likely to increase as the population ages and cardiovascular disease survival improves. We provide an overview of the definition and disease mechanisms of VCI and present a systematic literature review of the current evidence for the pharmacologic and nonpharmacologic therapies used to treat the VCI symptoms of cognitive dysfunction or to modify VCI through primary and secondary prevention. The Cochrane Database of Systematic Reviews was searched from 2005 to October 2010 using the keywords "vascular dementia" or "vascular cognitive impairment and therapy." MEDLINE was searched for English-language articles published within the last 10 years using the combined Medical Subject Headings (MeSH) "therapeutics and dementia," "vascular" or "vascular cognitive impairment." Although cholinesterase inhibitors and memantine produce small cognitive improvements in patients with VCI, these drugs do not improve global clinical outcomes and have adverse effects and costs. Selective serotonin reuptake inhibitors and dihydropyridine calcium channel blockers may improve short-term cognitive function in patients with VCI. Anti-hypertensive therapy with an ACE inhibitor-based regimen and statins may prevent the major subtype of VCI known as poststroke cognitive decline. Clinical and effectiveness studies with long-term follow-up are needed to determine the benefits and risks of pharmacologic and nonpharmacologic therapies to prevent and treat VCI. Given its growing health, social, and economic burden, the prevention and treatment of VCI are critical priorities for clinical care and research.

Poststroke depression and treatment effects on functional outcomes

BACKGROUND

Poststroke depression (PSD) is common after stroke; however, the relationship to poststroke function is inconclusive. Our objectives were to 1) determine the relationship between PSD at baseline (1 month poststroke) and function (12 weeks later) and 2) assess the impact of depression improvement on 12-week function among those with depression at baseline.

METHODS

We completed a secondary analysis of data from a cohort study of participants with and without PSD. We used logistic regression to identify factors associated with 12-week functional dependence for 1) all 367 participants and 2) the 174 participants with PSD.

RESULTS

In the PSD cohort, 3 characteristics were found to be independently associated with 12-week dependence: increased medical comorbidity (odds ratio [OR] 1.10, 95%confidence interval [CI] 1.02-1.22), increased stroke severity (OR 1.42, 95% CI 1.19-1.69), and increased baseline depression severity (OR 1.13, 95% CI 1.03-1.23). Depression severity was significantly different between those considered dependent and independent at 12 weeks (entire cohort, PHQ-9 7.31 vs 5.18, p = 0.008; depressed cohort, PHQ-9 9.94 vs 7.27, p = 0.019).

CONCLUSION

Among study participants with PSD, the severity of depression symptoms at baseline was associated with dependence; however, our results are inconclusive as to whether improvement of depression is independently associated with functional recovery at 12 weeks. Even if the treatment and improvement of PSD does not directly influence functional recovery poststroke, it is essential for PSD to be identified and treated due to its high symptom burden and association with other negative health and social outcomes.

Genetic influences on neural plasticity

Neural plasticity refers to the capability of the brain to alter function or structure in response to a range of events and is a crucial component of both functional recovery after injury and skill learning in healthy individuals. A number of factors influence neural plasticity and recovery of function after brain injury. The current review considers the impact of genetic factors. Polymorphisms in the human genes coding for brain-derived neurotrophic factor and apolipoprotein E have been studied in the context of plasticity and stroke recovery and are discussed here in detail. Several processes involved in plasticity and stroke recovery, such as depression or pharmacotherapy effects, are modulated by other genetic polymorphisms and are also discussed. Finally, new genetic polymorphisms that have not been studied in the context of stroke are proposed as new directions for study. A better understanding of genetic influences on recovery and response to therapy might allow improved treatment after a number of forms of central nervous system injury.

Cognitive enhancement by drugs in health and disease

Attempts to improve cognitive function in patients with brain disorders have become the focus of intensive research efforts. A recent emerging trend is the use of so-called cognitive enhancers by healthy individuals. Here, we consider some of the effects - positive and negative - that current drugs have in neurological conditions and healthy people. We conclude that, to date, experimental and clinical studies have demonstrated relatively modest overall effects, most probably because of substantial variability in response both across and within individuals. We discuss biological factors that might account for such variability and highlight the need to improve testing methods and to extend our understanding of how drugs modulate specific cognitive processes at the systems or network level.

Clinical trials for preventing post stroke cognitive impairment

Post stroke dementia (PSD) develops in up to 40% of patients and often co-exists with Alzheimer's disease in the elderly. Unsurprisingly, the combination of stroke and dementia is associated with considerable morbidity and mortality, and is devastating to patients and carers. Limited trial evidence suggests that lowering high blood pressure reduces the development of cognitive decline, vascular dementia and PSD, although whether this relates to the magnitude of BP reduction or specific drug classes remains unclear. Biological plausibility and/or existing studies suggest that other types of drug treatments might also be effective, including choline esterase inhibitors, lipid lowering agents, antiplatelet agents, and selective serotonin reuptake inhibitors. Preventing cognitive decline and dementia post stroke is critical and large definitive trials are now needed.

Post-stroke depression: can prediction help prevention?

Depression is common after stroke. Post-stroke depression (PSD) is an independent predictor of poor long-term functional outcome following stroke. PSD has been associated with poor social and rehabilitation outcomes, cognitive impairment and increased mortality. Prevalence varies widely between studies because of differences in patient selection, time, evaluation methods and diagnostic criteria. Approximately a third of stroke survivors may suffer from PSD. Potential confounders include anosognosia, apathy and emotional lability. The identification of risk factors is important to prevent and detect PSD early, and provide appropriate interventions. PSD may be associated with restriction in social activities and dependence in activities of daily living in the chronic phase of stroke. Pharmacologic and rehabilitation strategies are needed to treat PSD. More evidence is required before recommendations can be made about the routine use of antidepressants to prevent PSD.