Nathan Herrmann

A Meta-Analysis of Cytokines in Major Depression

BACKGROUND Major depression occurs in 4.4% to 20% of the general population. Studies suggest that major depression is accompanied by immune dysregulation and activation of the inflammatory response system (IRS). Our objective was to quantitatively summarize the data on concentrations of specific cytokines in patients diagnosed with a major depressive episode and controls. METHODS We performed a meta-analysis of studies measuring cytokine concentration in patients with major depression, with a database search of the English literature (to August 2009) and a manual search of references. RESULTS Twenty-four studies involving unstimulated measurements of cytokines in patients meeting DSM criteria for major depression were included in the meta-analysis; 13 for tumor necrosis factor (TNF)-alpha, 9 for interleukin (IL)-1beta, 16 for IL-6, 5 for IL-4, 5 for IL-2, 4 for IL-8, 6 for IL-10, and 4 for interferon (IFN)-gamma. There were significantly higher concentrations of TNF-alpha (p < .00001), weighted mean difference (WMD) (95% confidence interval) 3.97 pg/mL (2.24 to 5.71), in depressed subjects compared with control subjects (438 depressed/350 nondepressed). Also, IL-6 concentrations were significantly higher (p < .00001) in depressed subjects compared with control subjects (492 depressed/400 nondepressed) with an overall WMD of 1.78 pg/mL (1.23 to 2.33). There were no significant differences among depressed and nondepressed subjects for the other cytokines studied. CONCLUSIONS This meta-analysis reports significantly higher concentrations of the proinflammatory cytokines TNF-alpha and IL-6 in depressed subjects compared with control subjects. While both positive and negative results have been reported in individual studies, this meta-analytic result strengthens evidence that depression is accompanied by activation of the IRS.

Sedative hypnotics in older people with insomnia: meta-analysis of risks and benefits

Abstract Objectives To quantify and compare potential benefits (subjective reports of sleep variables) and risks (adverse events and morning-after psychomotor impairment) of short term treatment with sedative hypnotics in older people with insomnia. Data sources Medline, Embase, the Cochrane clinical trials database, PubMed, and PsychLit, 1966 to 2003; bibliographies of published reviews and meta-analyses; manufacturers of newer sedative hypnotics (zaleplon, zolpidem, zopiclone) regarding unpublished studies. Selection criteria Randomised controlled trials of any pharmacological treatment for insomnia for at least five consecutive nights in people aged 60 or over with insomnia and otherwise free of psychiatric or psychological disorders. Results 24 studies (involving 2417 participants) with extractable data met inclusion and exclusion criteria. Sleep quality improved (effect size 0.14, P < 0.05), total sleep time increased (mean 25.2 minutes, P < 0.001), and the number of night time awakenings decreased (0.63, P < 0.001) with sedative use compared with placebo. Adverse events were more common with sedatives than with placebo: adverse cognitive events were 4.78 times more common (95% confidence interval 1.47 to 15.47, P < 0.01); adverse psychomotor events were 2.61 times more common (1.12 to 6.09, P > 0.05), and reports of daytime fatigue were 3.82 times more common (1.88 to 7.80, P < 0.001) in people using any sedative compared with placebo. Conclusions Improvements in sleep with sedative use are statistically significant, but the magnitude of effect is small. The increased risk of adverse events is statistically significant and potentially clinically relevant in older people at risk of falls and cognitive impairment. In people over 60, the benefits of these drugs may not justify the increased risk, particularly if the patient has additional risk factors for cognitive or psychomotor adverse events.

Antipsychotic Drug Use and Mortality in Older Adults with Dementia

Context Recent reports suggest that antipsychotics are associated with increased risk for death in patients with dementia. Contribution This large, population-based study from Canada assessed the risk for death after dispensation of antipsychotics in older adults with dementia. New use of antipsychotics compared with nonuse was associated with increased risk for death at 30 days. Conventional agents were associated with higher risks than were atypical agents. Caution Sensitivity analyses showed that unmeasured confounders might diminish or erase observed associations. Implication Both conventional and atypical antipsychotics may be associated with an increased risk for death in elderly persons with dementia. The Editors Various challenging behavioral and psychological symptoms commonly develop in older adults with dementia and predispose them and their caregivers to poor outcomes (1). Nonpharmacologic strategies are recommended as first-line management for these symptoms (2), but they may be difficult to implement in clinical practice (3). For many reasons, antipsychotic medications are routinely prescribed in this setting (4, 5). Conventional antipsychotics, such as haloperidol, have been available since the 1950s. Meta-analyses of clinical trials evaluating conventional antipsychotics to treat agitation in dementia show that these agents have modest efficacy and important adverse effects compared with placebo (6, 7). In the past decade, use of newer atypical antipsychotics has been rapidly increasing in clinical practice because these agents were thought to produce fewer adverse effects than conventional agents (2). A Canadian study found that the prevalence of antipsychotic use in older adults increased from 2.2% in 1993 to 3.0% at the end of 2002. In that study, atypical antipsychotics, which were unavailable in 1993, accounted for 82.5% of all antipsychotics dispensed in 2002 (8). Short-term randomized, controlled trials (RCTs) have studied the role of atypical antipsychotics in the management of behavioral and psychological symptoms of dementia (2, 9). An RCT involving 421 outpatients with Alzheimer disease and psychosis, aggression, or agitation concluded that the adverse effects of these newer drugs offset their advantages (10). As a result, improvements in behavioral symptoms with antipsychotic drug treatment do not necessarily lead to improvements in overall quality of life for patients or their caregivers (11). In April 2005, the U.S. Food and Drug Administration (FDA) issued a public health advisory that the use of atypical antipsychotics to treat elderly patients with dementia was associated with an increased risk for death compared with placebo (12). In June 2005, Health Canada issued a similar warning and additional data (13). These warnings stem from reviews of RCTs that involve the atypical agents risperidone, olanzapine, quetiapine, and aripiprazole. The mortality rate was approximately 1.6 to 1.7 times higher than with placebo and was greater with antipsychotics than with placebo in 15 of the 17 trials reviewed by the U.S. FDA (12). The warnings extend to all currently available atypical antipsychotics. Other publications have provided support for these warnings and have raised further safety concerns about older conventional antipsychotics (1416). Important questions remain unanswered. Although RCTs provide the best evidence of treatment efficacy and harm, the individual RCTs in this case had low event rates. Reliable estimates of the mortality risk were generated only when data were combined by meta-analysis (14). Furthermore, these RCTs were generally short in duration and could not provide information about the long-term effect of antipsychotics on mortality (14, 17). Finally, these trials provide estimates of harm primarily for atypical antipsychotics. Relatively few data are available on harms associated with older conventional antipsychotics. Studies suggest that important differences may exist in the safety profiles of conventional and atypical agents (15, 16, 18, 19). Using population-based data, we sought to determine the risk for all-cause mortality in older adults with dementia who received atypical antipsychotics, conventional antipsychotics, or no antipsychotic. Because important baseline differences exist among these groups, we used propensity score matching to improve their comparability. We also evaluated the effect of duration of treatment with antipsychotics on the risk for death. Methods Data Sources Ontario is Canadas most populous province. During our study, Ontario had a population of approximately 12 million people, of whom 1.4 million were 65 years of age or older. A universally funded health program covers nearly all physician services, medications, and hospital services for patients 65 years of age or older in Ontario. Information from 4 administrative health care databases was linked to develop the study cohort: pharmacy records from the Ontario Drug Benefit program, hospitalization records from the Canadian Institute for Health Information Discharge Abstract Database, physician billing information for inpatient and outpatient services from the Ontario Health Insurance Plan, and basic demographic information and vital statistics from the Registered Persons Database. We used encrypted unique identifiers that are common among databases to link anonymous information on demographic characteristics and health services utilization for patients in our study. Little basic information on patients is missing in these databases. For example, the coding accuracy of drug claims in the Ontario Drug Benefit program database is excellent, with an error rate of only 0.7% (20). The study was approved by the ethics review board of Sunnybrook and Womens College Health Sciences Centre, Toronto, Ontario, Canada. Dementia Cohort We identified a cohort of all Ontario residents 66 years of age or older with a diagnosis of dementia (in the Ontario Health Insurance Plan or Discharge Abstract Database) between 1 April 1997 and 31 March 2002. To focus on antipsychotic drug treatment for behavioral and psychological symptoms of dementia, we excluded patients who had evidence of other psychotic disorders (such as schizophrenia) or were receiving palliative care services. To reduce the potential for selection bias, we studied only new users of antipsychotics and excluded those who had received antipsychotics in the year before cohort entry (21). Exposure to Antipsychotics We identified new use of antipsychotics if any agent available through the Ontario Drug Benefit program was dispensed after cohort entry. Cohort entry (that is, the index date) was defined as the date of the first dispensed antipsychotic drug. Available atypical drugs included olanzapine, quetiapine, and risperidone, and available conventional drugs included chlorpromazine, flupenthixol, fluphenazine, haloperidol, loxapine, pericyazine, perphenazine, pimozide, thioridazine, and trifluoperazine. Clozapine was rarely used in Ontario during the study period, and we therefore excluded patients who were receiving this medication. Other atypical antipsychotics (such as aripiprazole and ziprasidone) are not licensed for use in Canada. We decided that exposure to an antipsychotic was discontinued (and we censored follow-up) if the patient did not refill his or her antipsychotic prescription within an interval composed of the days of drug supply plus a grace period of 20%. For example, we censored follow-up for a patient who did not refill his or her 60-day antipsychotic prescription within 72 days. We also censored follow-up for patients who switched from atypical to conventional antipsychotics (or vice versa). However, we continued follow-up for patients who switched from 1 atypical antipsychotic to another, because data suggest no statistically significant difference in the risk for death associated with individual drugs in this class (13, 14, 16). We applied the same rules to conventional antipsychotics. All-Cause Mortality The primary outcome was all-cause mortality, as recorded in the Registered Persons Database (for patients who were not hospitalized at the time of death) or the Discharge Abstract Database (for patients who died while hospitalized). To assess the influence of the duration of antipsychotic exposure on the outcome, we evaluated the risk for death at 30, 60, 120, and 180 days after the initial dispensing of antipsychotic medication. Cohort Matching We stratified the dementia cohort to support separate analyses among persons living in the community and those residing in long-term care at cohort entry. Studies have demonstrated that rates of antipsychotic prescribing are substantial among older adults newly admitted to long-term care facilities (4). Furthermore, long-term care residents typically carry a greater burden of comorbid disease and are more vulnerable to adverse drug events than are their counterparts in the community (22, 23). Our first objective was to determine the risk for death among older adults with dementia who received atypical antipsychotics compared with those who were not exposed to any antipsychotic. Because antipsychotic use was not randomly assigned in the study cohorts, we addressed potential confounding and selection biases by developing a propensity score for antipsychotic use. We then applied this score to match users of atypical antipsychotics with nonusers in the dementia cohort. The rationale and methods underlying the use of a propensity score for a proposed causal exposure variable are described elsewhere (24). Recent studies provide guidance on the selection of variables to include in the propensity score (25, 26). We developed a logistic regression model by using 42 covariates describing patient characteristics. Tables 1 and 2 list many of the characteristics included in the propensity score. After a structured and iterative assessment of the balance of measured covariates betwe

A Meta-Analysis of Cytokines in Alzheimer's Disease

BACKGROUND Studies suggest that inflammation is involved in the neurodegenerative cascade leading to Alzheimers disease (AD) pathology and symptoms. This study sought to quantitatively summarize the clinical cytokine data. METHODS Original English language peer-reviewed studies measuring cytokine concentrations in AD and healthy control subjects were included. Mean (± standard deviation) cytokine concentrations for AD and control subjects were extracted. RESULTS Forty studies measuring peripheral blood cytokine concentrations and 14 measuring cerebrospinal fluid (CSF) cytokine concentrations were included. In peripheral blood, there were significantly higher concentrations (weighted mean difference [95% confidence interval]) of interleukin (IL)-6 (2.86 [1.68, 4.04] pg/mL, p < .00001, N[AD/control subjects] = 985/680, 14 studies), tumor necrosis factor (TNF)-α (3.25 [.76, 5.74] pg/mL, p = .01, N = 680/447, 14 studies), IL-1β (.55 [.32, .78] pg/mL, p < .00001, N = 574/370, 10 studies), transforming growth factor (TGF)-β (67.23 [28.62, 105.83] pg/mL, p = .0006, N = 190/158, 5 studies), IL-12 (7.60 [5.58, 9.62] pg/mL, p < .00001, N = 148/106, 5 studies), and IL-18 (15.82 [1.98, 29.66] pg/mL, p = .03, N = 131/94, 4 studies) but not of IL-4, IL-8, IL-10, interferon-γ, or C-reactive protein in AD subjects compared with control subjects. There were significantly higher concentrations of TGF-β (7.81 [2.27, 13.35] pg/mL, p =.006, N = 113/114, 5 studies) but not IL-6, TNF-α, and IL-1β in the CSF of AD subjects compared with control subjects. CONCLUSIONS These results strengthen the clinical evidence that AD is accompanied by an inflammatory response, particularly higher peripheral concentrations of IL-6, TNF-α, IL-1β, TGF-β, IL-12 and IL-18 and higher CSF concentrations of TGF-β.

The Sunnybrook Stroke Study A Prospective Study of Depressive Symptoms and Functional Outcome

BACKGROUND AND PURPOSE To assess the prevalence of depressive symptoms, their clinical correlates, and the effects of depressive symptoms on stroke recovery, a relatively unselected, well-diagnosed cohort of consecutive stroke survivors was followed prospectively. METHODS Consecutive admissions to a regional stroke center who met World Health Organization and National Institute of Neurological Disorders and Stroke criteria for stroke were eligible. Subarachnoid hemorrhage and brain stem strokes were excluded. Patients underwent CT, single-photon emission CT, and standardized neurological and cognitive examinations at entry. At 3 months and 1 year after stroke, depressive symptoms were assessed with the Montgomery Asberg Depression Rating Scale (MADRS) and the Zung Self-Rating Depression Scale (SDS). Functional outcome was measured with the Functional Independence Measure, and handicap was assessed by the Oxford Handicap Scale. RESULTS We assessed 436 patients at entry (mean +/- SD age, 74.9 +/- 11.6 years). There were 150 patients available for assessment at 3 months and 136 at 1 year. Marked depressive symptoms were noted in 22% (SDS) to 27% (MADRS) at 3 months and 21% (SDS) to 22% (MADRS) at 1 year. Patents with marked depressive symptoms had more neurological impairment (P<.008), were more likely to be female (P<.05), and were more likely to have previous histories of depression (P<.03). There was no relationship between depressive symptoms and age, lesion volume, or side of lesion. Depressive symptoms were correlated with functional outcome (r = -.31, P<.0001) and handicap (r = .41, P<.0001) at 3 months and 1 year (r= -.28, P<.001; r = .35, P<.0001). CONCLUSIONS Depressive symptoms and functional outcome are correlated. In view of the prevalence of depressive symptoms in this population, diagnosis and treatment of depression are important in optimizing recovery.

Atypical antipsychotic drugs and risk of ischaemic stroke: population based retrospective cohort study

Abstract Objective To compare the incidence of admissions to hospital for stroke among older adults with dementia receiving atypical or typical antipsychotics. Design Population based retrospective cohort study. Setting Ontario, Canada. Patients 32 710 older adults (≤ 65 years) with dementia (17 845 dispensed an atypical antipsychotic and 14 865 dispensed a typical antipsychotic). Main outcome measures Admission to hospital with the most responsible diagnosis (single most important condition responsible for the patients admission) of ischaemic stroke. Observation of patients until they were either admitted to hospital with ischaemic stroke, stopped taking antipsychotics, died, or the study ended. Results After adjustment for potential confounders, participants receiving atypical antipsychotics showed no significant increase in risk of ischaemic stroke compared with those receiving typical antipsychotics (adjusted hazard ratio 1.01, 95% confidence interval 0.81 to 1.26). This finding was consistent in a series of subgroup analyses, including ones of individual atypical antipsychotic drugs (risperidone, olanzapine, and quetiapine) and selected subpopulations of the main cohorts. Conclusion Older adults with dementia who take atypical antipsychotics have a similar risk of ischaemic stroke to those taking typical antipsychotics.

Effect of rivastigmine on delay to diagnosis of Alzheimer's disease from mild cognitive impairment: the InDDEx study

OBJECTIVE To assess the effect of rivastigmine in patients with mild cognitive impairment (MCI) on the time to clinical diagnosis of Alzheimers disease (AD) and the rate of cognitive decline. METHODS The study was a double-blind, randomised, placebo-controlled trial of up to 48 months. All patients had MCI operationally defined by having cognitive symptoms, a global clinical dementia rating stage of 0.5, a score of less than 9 on the New York University delayed paragraph recall test, and by not meeting the diagnostic criteria for AD. Primary efficacy variables were time to clinical diagnosis of AD, and change in performance on a cognitive test battery. This study is registered with the US National Institutes of Health clinical trials database (ClinicalTrials.gov), number NCT00000174. FINDINGS Of 1018 study patients enrolled, 508 were randomly assigned to rivastigmine and 510 to placebo; 17.3% of patients on rivastigmine and 21.4% on placebo progressed to AD (hazard ratio 0.85 [95% CI 0.64-1.12]; p=0.225). There was no significant difference between the rivastigmine and placebo groups on the standardised Z score for the cognitive test battery measured as mean change from baseline to endpoint (-0.10 [95% CI -0.63 to 0.44], p=0.726). Serious adverse events were reported by 141 (27.9%) rivastigmine-treated patients and 155 (30.5%) patients on placebo; adverse events of all types were reported by 483 (95.6%) rivastigmine-treated patients and 472 (92.7%) placebo-treated patients. The predominant adverse events were cholinergic: the frequencies of nausea, vomiting, diarrhoea, and dizziness were two to four times higher in the rivastigmine group than in the placebo group. INTERPRETATION There was no significant benefit of rivastigmine on the progression rate to AD or on cognitive function over 4 years. The overall rate of progression from MCI to AD in this randomised clinical trial was much lower than predicted. Rivastigmine treatment was not associated with any significant safety concerns.

Functional and Neuroanatomic Correlations in Poststroke Depression The Sunnybrook Stroke Study

BACKGROUND AND PURPOSE The purpose of our study was to determine the functional and neuroanatomic correlates of poststroke depressive symptoms. METHODS Patients with consecutive admissions to a regional stroke center for new-onset unilateral hemispheric stroke who met World Health Organization and National Institute of Neurological and Communicative Disorders and Stroke criteria were eligible for inclusion in a longitudinal study. Acutely, patients underwent CT scanning, and at 3 months and 1 year after stroke, depressive symptoms were assessed by using both the Montgomery-Asberg Depression Rating Scale and the Zung Self-Rating Depression Scale. The Functional Independence Measure (FIM) served as an indication of functional outcome and was obtained at 1 month, 3 months, and 1 year after stroke, along with other demographic information. The Talairach and Tournoux stereotactic atlas was used for the primary determination of CT lesion localization. Lesion proximity to the anterior frontal pole was also measured. RESULTS Eighty-one patients participated in the longitudinal study. Stepwise linear regression analyses generated a highly significant model (F(3,76)=9.8, R(2)=28%, P<0.0005), with lower 1-month total FIM scores, living at home, and damage to the inferior frontal region predicting higher depression scores at 3 months. Similarly, lower 3-month total FIM scores correlated with higher 3-month depression scores, and lower 1-year total FIM scores correlated with higher 1-year depression scores. CONCLUSIONS Functional measures correlated with poststroke depression across time and, together with neuroanatomic measures, predicted depressive symptoms longitudinally. Although inferior frontal lesion location, irrespective of side, appeared to play a role as a risk factor in this study, the degree of functional dependence after stroke imparted the greatest risk.

Current and Emerging Drug Treatment Options for Alzheimer’s Disease

Alzheimer’s disease (AD) is a progressive and ultimately fatal condition that causes debilitating memory loss and extensive deterioration of cognitive and functional abilities. Currently available treatments for AD (donepezil, rivastigmine, galantamine and memantine) are symptomatic and do not decelerate or prevent the progression of the disease. These therapies demonstrate modest, but particularly consistent, benefit for cognition, global status and functional ability. The search for disease-modifying interventions has focused largely on compounds targeting the amyloid-β pathway. To date, the treatments targeting this pathway, such as tramiprosate and semagacestat, have been unsuccessful in demonstrating efficacy in clinical stages of testing. At this point, it is likely that not only amyloid-β aggregation but other possible neuronal mechanisms — such as hyperphosphorylated tau, neuro-inflammation and other processes — play important roles in the pathophysiology of this multifactorial disorder. Development of better disease models and biomarkers is essential for the advancement of knowledge of the disease mechanisms. This systematic review critically examines the efficacy and safety data for currently approved drugs and emerging treatments in AD, as well as discussing the present and future directions of innovation in this field.

Do atypical antipsychotics cause stroke

Post hoc analyses of pooled results from 11 randomised controlled trials of risperidone and olanzapine in elderly dementia subjects revealed an increased incidence of cerebrovascular adverse events compared with placebo. Reanalysis of the risperidone trials suggests that some of the increased incidence may be accounted for by nonspecific events that were not strokes. Large observational administrative health database studies appear to confirm that risperidone and olanzapine are not associated with an increased risk of stroke in elderly patients compared with typical antipsychotics or untreated dementia patients. A larger number of subjects with vascular and mixed dementias were included in the risperidone studies compared with the olanzapine studies, which likely accounts for the increased incidence of cerebrovascular adverse events in the risperidone trials compared with the olanzapine studies. Potential mechanisms proposed to explain an association between atypical antipsychotics and cerebrovascular adverse events include thromboembolic effects, cardiovascular effects (e.g. orthostatic hypotension, arrhythmias), excessive sedation resulting in dehydration and haemoconcentration, and hyperprolactinaemia. However, there is little evidence to support these hypothesised mechanisms at present. The association between atypical antipsychotics and cerebrovascular adverse events requires further clarification. At the present time, this association is another factor that clinicians should consider when weighing the risks and benefits of treating behavioural and psychological disturbances in elderly dementia patients.