David E. Kemp

Inflammation and the phenomenology, pathophysiology, comorbidity, and treatment of bipolar disorder: a systematic review of the literature.

OBJECTIVE To review extant literature implicating inflammation in the pathophysiology of bipolar disorder. Furthermore, we review evidence regarding the anti-inflammatory actions of mood-stabilizing medication, the putative reciprocal association of inflammation with behavioral parameters and medical burden in bipolar disorder, and the potential role of anti-inflammatory agents in the treatment of bipolar disorder. DATA SOURCES MEDLINE and PubMed searches were conducted of English-language articles published from 1950 to April 2008 using the search terms bipolar disorder, manic, or mania, cross-referenced with inflammation, inflammatory, interleukin, cytokine, C-reactive protein, or tumor necrosis factor. The search, which was conducted most recently on August 20, 2008, was supplemented by manually reviewing reference lists from the identified publications. STUDY SELECTION Articles selected for review were based on adequacy of sample size, the use of standardized experimental procedures, validated assessment measures, and overall manuscript quality. DATA EXTRACTION Studies were reviewed for statistical comparisons of cytokines among persons with and without bipolar disorder, during symptomatic and non-symptomatic intervals and before and after pharmacologic treatment. Significant and nonsignificant findings were tabulated. DATA SYNTHESIS Available evidence indicates that bipolar disorder and inflammation are linked through shared genetic polymorphisms and gene expression as well as altered cytokine levels during symptomatic (i.e., mania and depression) and asymptomatic intervals. However, results are inconsistent. Several conventional mood stabilizers have anti-inflammatory properties. The cyclooxygenase-2-selective anti-inflammatory celecoxib may offer antidepressant effects. Inflammation is closely linked with behavioral parameters such as exercise, sleep, alcohol abuse, and smoking, as well as with medical comorbidities including coronary artery disease, obesity and insulin resistance, osteoporosis, and pain. Methodological limitations precluding definitive conclusions are heterogeneity in sample composition, cytokine assessment procedures, and treatment regimens. The inclusion of multiple ethnic groups introduces another source of variability but also increases the generalizability of study findings. CONCLUSION Inflammation appears relevant to bipolar disorder across several important domains. Further research is warranted to parse the reciprocal associations between inflammation and symptoms, comorbidities, and treatments in bipolar disorder. Studies of this topic among youth are needed and may best serve this purpose.

Antipsychotic-Induced Extrapyramidal Side Effects in Bipolar Disorder and Schizophrenia: A Systematic Review

Objectives: Newer atypical antipsychotics have been reported to cause a lower incidence of extrapyramidal side effects (EPS) than conventional agents. This review is to compare antipsychotic-induced EPS relative to placebo in bipolar disorder (BPD) and schizophrenia. Methods: English-language literature cited in Medline was searched with terms antipsychotics, placebo-controlled trial, and bipolar disorder or schizophrenia and then with antipsychotic (generic/brand name), safety, akathisia, EPS, or anticholinergic use, bipolar mania/depression, BPD, or schizophrenia, and randomized clinical trial. Randomized, double-blind, placebo-controlled, monotherapy studies with comparable doses in both BPD and schizophrenia were included. Absolute risk increase and number needed to treat to harm (NNTH) for akathisia, overall EPS, and anticholinergic use relative to placebo were estimated. Results: Eleven trials in mania, 4 in bipolar depression, and 8 in schizophrenia were included. Haloperidol significantly increased the risk for akathisia, overall EPS, and anticholinergic use in both mania and schizophrenia, with a larger magnitude in mania, an NNTH for akathisia of 4 versus 7, EPS of 3 versus 5, and anticholinergic use of 2 versus 4, respectively Among atypical antipsychotics, only ziprasidone significantly increased the risk for overall EPS and anticholinergic use in both mania and schizophrenia, again with larger differences in mania, an NNTH for overall EPS of 11 versus 19, and anticholinergic use of 5 versus 9. In addition, risks were significantly increased for overall EPS (NNTH = 5) and anticholinergic use (NNTH = 5) in risperidone-treated mania, akathisia in aripiprazole-treated mania (NNTH = 9) and bipolar depression (NNTH = 5), and overall EPS (NNTH = 19) in quetiapine-treated bipolar depression. Conclusions: Bipolar patients, especially in depression, were more vulnerable to having acute antipsychotic-induced movement disorders than those with schizophrenia.

Bipolar disorder and metabolic syndrome: an international perspective.

INTRODUCTION The ubiquity and hazards posed by abnormal body composition and metabolic parameters in the bipolar population are a priority research and clinical issue. Herein, we summarize and synthesize international studies describing the rate of US National Cholesterol Education Program (NCEP) Expert Panel on Detection, Evaluation, and Treatment of High Blood Cholesterol in Adults (Adult Treatment Panel III [ATP III])- and International Diabetes Federation (IDF)-defined metabolic syndrome and its criterion components in individuals with bipolar disorder. METHODS We conducted a PubMed search of all English-language articles published between January 2005 and July 2009 with the following search terms: metabolic syndrome and bipolar disorder, mania and manic-depression. Articles selected for review were based on adequacy of sample size, the use of standardized experimental procedures, validated assessment measures, and overall manuscript quality. RESULTS The rate of metabolic syndrome in individuals with bipolar disorder is increased relative to the general population. Disparate estimates are reported ranging from comparability to approximately twofold greater than the general population. The increased hazard for metabolic syndrome amongst bipolar individuals is now documented in twelve countries from Europe, Australia, Asia, North and South America. The co-occurrence of metabolic syndrome in the bipolar population is associated with a more complex illness presentation, less favourable response to treatment, and adverse course and outcome. The association between metabolic syndrome and bipolar disorder is mediated/moderated by both iatrogenic and non-iatrogenic factors. DISCUSSION The increased hazard for metabolic syndrome in bipolar populations is due to the clustering of traditional (and emerging) risk factors as well as iatrogenic and health systems factors. Extant data support recommendations for prioritizing, surveillance, prevention, diagnosis and management of metabolic syndrome as routine care of the bipolar patient.

Medical comorbidity in bipolar disorder: relationship between illnesses of the endocrine/metabolic system and treatment outcome.

OBJECTIVE The present study examined the relationship between medical burden in bipolar disorder and several indicators of illness severity and outcome. It was hypothesized that illnesses of the endocrine/metabolic system would be associated with greater psychiatric symptom burden and would impact the response to treatment with lithium and valproate. METHODS Data were analyzed from two studies evaluating lithium and valproate for rapid-cycling presentations of bipolar I and II disorder. General medical comorbidity was assessed by the Cumulative Illness Rating Scale (CIRS). Descriptive statistics and logistic regression analyses were conducted to explore the relationships between medical burden, body mass index (BMI), substance use disorder status, and depressive symptom severity. RESULTS Of 225 patients enrolled, 41.8% had a recent substance use disorder, 50.7% were male, and 69.8% had bipolar I disorder. The mean age of the sample was 36.8 (SD = 10.8) years old. The mean number of comorbid medical disorders per patient was 2.5 (SD = 2.5), and the mean CIRS total score was 4.3 (SD = 3.1). A significant positive correlation was observed between baseline depression severity and the number of organ systems affected by medical illness (p = 0.04). Illnesses of the endocrine/metabolic system were inversely correlated with remission from depressive symptoms (p = 0.02), and obesity was specifically associated with poorer treatment outcome. For every 1-unit increase in BMI, the likelihood of response decreased by 7.5% [odds ratio (OR) = 0.93, 95% confidence interval (CI): 0.87- 0.99; p = 0.02] and the likelihood of remission decreased by 7.3% (OR = 0.93, 95% CI: 0.87-0.99; p = 0.03). The effect of comorbid substance use on the likelihood of response differed significantly according to baseline BMI. The presence of a comorbid substance use disorder resulted in lower odds of response, but only among patients with a BMI > or = 23 (p = 0.02). CONCLUSION Among patients with rapid-cycling bipolar disorder receiving lithium and valproate, endocrine/metabolic illnesses, including overweight and obesity, appear to be associated with greater depressive symptom severity and poorer treatment outcomes.

Treatment-emergent mania in unipolar and bipolar depression: focus on repetitive transcranial magnetic stimulation

This review focused on the treatment-emergent mania/hypomania (TEM) associated with repetitive transcranial magnetic stimulation (rTMS) treatment of depression. English-language literature published from 1966-2006 and indexed in Medline was searched. Ten of 53 randomized controlled trials on rTMS treatment of depression specifically addressed TEM. The pooled TEM rate is 0.84% for the active treatment group and 0.73% for the sham group. The difference is not statistically significant. Along with case reports, a total of 13 cases of TEM associated with rTMS treatment of depression have been published. Most of these patients were diagnosed with bipolar disorder and the majority of patients experiencing TEM took medication concurrent with rTMS. The parameters of rTMS used in these cases were scattered over the spectrum of major parameters explored in previous studies. Most train durations and intervals were within the published safety guidelines of the field. Reducing the frequency of sessions from two per day to one per day might be associated with a lower likelihood of TEM recurrence. The severity of manic symptoms varied significantly, but all cases responded to treatment that included a decrease or discontinuation of antidepressant and/or rTMS treatment and/or use of anti-manic medication. Current data suggests that rTMS treatment carries a slight risk of TEM that is not statistically higher than that associated with sham treatment. More systematic studies are needed to better understand TEM associated with rTMS. Special precautions and measures should be adopted to prevent, monitor, and manage TEM in research and practice.

Second-generation antipsychotics in major depressive disorder: update and clinical perspective

Purpose of review The aim of this systematic review was to examine the efficacy and safety of second-generation antipsychotics (SGAs) in nonpsychotic major depressive disorder (MDD). Recent findings In MDD, SGA monotherapy or adjunctive therapy to conventional antidepressants showed rapid onset of antidepressant efficacy. Although maintenance data are limited, quetiapine monotherapy, risperidone adjunctive therapy, and amisulpride adjunctive therapy significantly delayed the time to relapse as compared with placebo. In general, extrapyramidal symptoms appeared to be low with SGAs, but a higher incidence of akathisia was observed with aripiprazole. An elevated risk of weight gain was observed with olanzapine–fluoxetine combination, risperidone, aripiprazole, and quetiapine compared with placebo. At present, there are insufficient data to confidently distinguish between different SGAs in the treatment of MDD. A recent meta-analysis found that adjunctive SGAs were significantly more effective than placebo, but differences in efficacy were not identified among the studied agents, nor were outcomes affected by trial duration or the method of establishing treatment resistance. Summary Both SGA monotherapy and adjunctive therapy showed greater efficacy in the treatment of MDD than placebo, but augmentation is more widely utilized in treatment-resistant depression. Clinicians should routinely monitor for cardiometabolic side-effects and extrapyramidal symptoms during SGA therapy.

Use of Insulin Sensitizers for the Treatment of Major Depressive Disorder: A Pilot Study of Pioglitazone for Major Depression Accompanied by Abdominal Obesity

OBJECTIVE This study was conducted to examine the safety and efficacy of pioglitazone, a thiazolidinedione insulin sensitizer, in adult outpatients with major depressive disorder. METHOD In a 12-week, open-label, flexible-dose study, 23 patients with major depressive disorder received pioglitazone monotherapy or adjunctive therapy initiated at 15 mg daily. Subjects were required to meet criteria for abdominal obesity (waist circumference>35 in. in women and >40 in. in men) or metabolic syndrome. The primary efficacy measure was the change from baseline to Week 12 on the Inventory of Depressive Symptomatology (IDS) total score. Partial responders (≥25% decrease in IDS total score) were eligible to participate in an optional extension phase for an additional three months. RESULTS Pioglitazone decreased depression symptom severity from a total IDS score of 40.3±1.8 to 19.2±1.8 at Week 12 (p<.001). Among partial responders (≥25% decrease in IDS total score), an improvement in depressive symptoms was maintained during an additional 3-month extension phase (total duration=24 weeks) according to IDS total scores (p<.001). Patients experienced a reduction in insulin resistance from baseline to Week 12 according to the log homeostasis model assessment (-0.8±0.75; p<.001) and a significant reduction in inflammation as measured by log highly- sensitive C-reactive protein (-0.87±0.72; p<.001). During the current episode, the majority of participants (74%, n=17), had already failed at least one antidepressant trial. The most common side effects were headache and dizziness; no patient discontinued due to side effects. LIMITATIONS These data are limited by a small sample size and an open-label study design with no placebo control. CONCLUSION Although preliminary, pioglitazone appears to reduce depression severity and improve several markers of cardiometabolic risk, including insulin resistance and inflammation. Larger, placebo-controlled studies are indicated.

General Medical Burden in Bipolar Disorder: Findings from the LiTMUS Comparative Effectiveness Trial

This study examined general medical illnesses and their association with clinical features of bipolar disorder.

Number needed to treat to harm for discontinuation due to adverse events in the treatment of bipolar depression, major depressive disorder, and generalized anxiety disorder with atypical antipsychotics.

OBJECTIVE To estimate the number needed to treat to harm (NNTH) for discontinuation due to adverse events with atypical antipsychotics relative to placebo during the treatment of bipolar depression, major depressive disorder (MDD), and generalized anxiety disorder (GAD). DATA SOURCES English-language literature published and cited in MEDLINE from January 1966 to May 2009 was searched with the terms antipsychotic, atypical antipsychotic, generic and brand names of atypical antipsychotics, safety, tolerability, discontinuation due to adverse events, somnolence, sedation, weight gain, akathisia, or extrapyramidal side effect; and bipolar depression, major depressive disorder, or generalized anxiety disorder; and randomized, placebo-controlled clinical trial. This search was augmented with a manual search. STUDY SELECTION Studies with a cumulative sample of ≥ 100 patients were included. DATA EXTRACTION The NNTHs for discontinuation due to adverse events, somnolence, sedation, ≥ 7% weight gain, and akathisia relative to placebo were estimated with 95% confidence intervals to reflect the magnitude of variance. DATA SYNTHESIS Five studies in bipolar depression, 10 studies in MDD, and 4 studies in GAD were identified. Aripiprazole and olanzapine have been studied in bipolar depression and refractory MDD. Only quetiapine extended release (quetiapine-XR) has been studied in 3 psychiatric conditions with different fixed dosing schedules. For aripiprazole, the mean NNTH for discontinuation due to adverse events was 14 in bipolar depression, but was not significantly different from placebo in MDD. For olanzapine, the mean NNTHs were 24 in bipolar depression and 9 in MDD. The risk for discontinuation due to adverse events during quetiapine-XR treatment appeared to be associated with dose. For quetiapine-XR 300 mg/d, the NNTHs for discontinuation due to adverse events were 9 for bipolar depression, 8 for refractory MDD, 9 for MDD, and 5 for GAD. CONCLUSIONS At the same dose of quetiapine-XR, patients with GAD appeared to have a lower tolerability than those with bipolar depression or MDD. Due to flexible dosing, the risk for discontinuation due to adverse events in the treatment of bipolar depression, MDD, or GAD with other atypical antipsychotics could not be compared.

Medical and substance use comorbidity in bipolar disorder.

OBJECTIVE National Comorbidity Survey data indicate that bipolar disorder is characterized by high lifetime rates of co-occurring anxiety and substance use disorders (SUDs). Although compelling evidence suggests SUD comorbidity predicts non-response to treatment, the relationship between medical comorbidity and treatment response has not been studied adequately. In an attempt to understand the impact of medical comorbidity on treatment outcome, an analysis was conducted to inform the relationship between co-occurring medical illness, the phenomenology of bipolar disorder, and response to treatment with mood stabilizers. METHOD A total of 98 adult outpatients with rapid-cycling bipolar I or II disorder and co-occurring SUDs were prospectively treated with the combination of lithium and valproate for up to 24 weeks. A logistic regression analysis was conducted to explore the relationship between phenomenology, response to mood stabilizers, and medical comorbidity as assessed by the Cumulative Illness Rating Scale (CIRS). High and low medical comorbidity burden were defined as a CIRS total score > or = 4 and < or = 3, respectively. RESULTS Every patient enrolled into this study had at least 1 medical illness (most commonly respiratory, 72%) and on average had 4.9 different medical conditions. Over half of patients (52%) exhibited illnesses across four or more different organ systems, 24% had uncontrollable medical illnesses, and the mean overall total CIRS score was 5.56. The average body mass index (BMI) was 28.1 with 38% being overweight and 29% being obese. High medical burden was observed in 64% and was most strongly predicted by a diagnosis of bipolar I disorder (OR=34.9, p=0.002, 95%CI=3.9-316.1). A history of attempted suicide (OR=10.3, p=0.01, 95%CI=1.7-62.0), a history of physical abuse (OR=7.6, p=0.03, 95%CI=1.3-45.7) and advancing age (OR=1.2, p<0.001, 95%CI=1.1-1.3) also independently predicted a high burden of general medical problems. Only 21% (N=21) of subjects enrolled into this study showed a bimodal response to treatment with lithium plus valproate, and neither BMI nor any summary CIRS measure predicted response. CONCLUSION Rapid cycling with co-occurring substance use is not only associated with poor response to mood stabilizers, but is also a harbinger of serious medical problems. A high burden of medical comorbidity was associated with the bipolar I subtype, a history of attempted suicide, a history of physical abuse, and advancing age.