Antipsychotics in the treatment of bipolar disorder

Sex differences in antipsychotic-related triglyceride levels are associated with metabolic hormone differences in patients with severe mental disorders

BACKGROUND

Adverse effects of antipsychotics (AP) contribute to cardiovascular disease (CVD) risk in patients with severe mental disorders (SMD). We investigated sex differences in AP-related CVD risk factors and the role of metabolic hormones.

METHODS

Patients with SMD (N = 1791) receiving AP with different CVD risk were recruited and grouped into olanzapine and/or clozapine (N = 532), other APs (N = 744) or no use of APs (N = 515). Associations between CVD risk factor (total cholesterol, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), triglycerides (TG), body mass index (BMI), glucose, blood pressure), sex and AP groups were tested in multiple linear regression with interactions, controlling for diagnostic group, lifestyle factors, polypharmacy, age and ethnicity. Next, we tested associations between sex differences in AP-related CVD risk factors and metabolic regulatory hormones.

RESULTS

AP groups and male sex were significantly associated with higher levels of LDL-C, TG and BMI, and lower levels of HDL-C. Significant interaction between AP groups and sex were found for TG (p = 0.017), with larger increase in males. Serum adiponectin, insulin, cortisol, leptin, testosterone, free thyroxine and thyroid-stimulating hormone (TSH) were associated with TG levels (all p ≤ 0.001), and a significant interaction with sex for insulin (p = 0.005), cortisol (p = 0.016), leptin (p < 0.001) and TSH (p = 0.001).

CONCLUSIONS

We found more severe AP-related CVD risk factors in male patients with SMD. The male-dependent increase in TG levels was associated with leptin, insulin, cortisol and TSH levels. Clinicians treating patients with SMD should be aware of increased vulnerability for AP-related lipid abnormalities in males.

Polygenic risk scores across the extended psychosis spectrum

As early detection of symptoms in the subclinical to clinical psychosis spectrum may improve health outcomes, knowing the probabilistic susceptibility of developing a disorder could guide mitigation measures and clinical intervention. In this context, polygenic risk scores (PRSs) quantifying the additive effects of multiple common genetic variants hold the potential to predict complex diseases and index severity gradients. PRSs for schizophrenia (SZ) and bipolar disorder (BD) were computed using Bayesian regression and continuous shrinkage priors based on the latest SZ and BD genome-wide association studies (Psychiatric Genomics Consortium, third release). Eight well-phenotyped groups (n = 1580; 56% males) were assessed: control (n = 305), lower (n = 117) and higher (n = 113) schizotypy (both groups of healthy individuals), at-risk for psychosis (n = 120), BD type-I (n = 359), BD type-II (n = 96), schizoaffective disorder (n = 86), and SZ groups (n = 384). PRS differences were investigated for binary traits and the quantitative Positive and Negative Syndrome Scale. Both BD-PRS and SZ-PRS significantly differentiated controls from at-risk and clinical groups (Nagelkerke's pseudo-R2: 1.3-7.7%), except for BD type-II for SZ-PRS. Out of 28 pairwise comparisons for SZ-PRS and BD-PRS, 9 and 12, respectively, reached the Bonferroni-corrected significance. BD-PRS differed between control and at-risk groups, but not between at-risk and BD type-I groups. There was no difference between controls and schizotypy. SZ-PRSs, but not BD-PRSs, were positively associated with transdiagnostic symptomology. Overall, PRSs support the continuum model across the psychosis spectrum at the genomic level with possible irregularities for schizotypy. The at-risk state demands heightened clinical attention and research addressing symptom course specifiers. Continued efforts are needed to refine the diagnostic and prognostic accuracy of PRSs in mental healthcare.

Role of COMT V158M Polymorphism in the Development of Dystonia after Administration of Antipsychotic Drugs

Antipsychotics (APDs) represent the main pharmacological strategy in the treatment of schizophrenia; however, their administration often may result in severe adverse effects, such as extrapyramidal symptoms. Typically, dystonic movements are considered the result of impaired function and/or abnormalities of dopaminergic neurotransmission/signaling in the basal ganglia. The catechol O-methyltransferase (COMT) gene is located within the 22q11.2 region, and its product is an enzyme involved in transferring a methyl group from S-adenosylmethionine to catecholamines, including dopamine. Studies showed that COMT Val158Met polymorphism modifies enzymatic activity and, consequently, synaptic dopamine concentration in specific brain areas. We identified a patient with 22q11.2 deletion syndrome presenting with cervical and trunk dystonia after paliperidone administration, which persisted even after drug discontinuation. Given the patient’s genetic condition, we hypothesized that the dopaminergic dysfunction had been aggravated by COMT involvement, thus causing dystonia. In line with this hypothesis, we carried out a study on psychiatric patients in chronic treatment with APD to evaluate the distribution of the COMT Val158Met polymorphism and its role in the onset of adverse extrapyramidal symptoms. The study included four patients with dystonia after administration of APDs compared to 17 patients who never presented adverse drug reactions. Our data suggest that the Val/Val and Met/Met polymorphisms of the COMT gene are associated with a protective effect for the development of collateral extrapyramidal symptoms in patients treated with APDs, while the Val/Met genotype could be considered a risk factor for the development of dystonia after APDs administration.

Risk Factors of Metabolic Syndrome Among Patients Receiving Antipsychotics: A Retrospective Study

This study aimed to assess the differential effects of first-generation (FGA) and second-generation antipsychotics (SGA) on the prevalence of risk factors for metabolic syndrome among mentally ill patients in Qatar. We also wanted to check if there is proper adherence with the guidelines for prescribing antipsychotics and the monitoring of metabolic effects in this population. We collected the available retrospective data (socio-demographic, psychiatric, anthropometric, and metabolic measures) from the records of 439 patients maintained on antipsychotics. The majority were males, married, employed, having a psychotic disorder, and receiving SGA. Patients on SGA showed more obesity, higher BP, and more elevated triglycerides compared to those on FGA. The prevalence of the abnormal metabolic measures was high in this sample, but those on SGA showed a significantly higher prevalence of abnormal body mass index and BP. Obesity and hypertension were common in patients maintained on antipsychotics, especially those on SGA. Polypharmacy was common, and many metabolic measures were not monitored properly in those maintained on antipsychotics. More prospective studies with guided monitoring of the patients' clinical status and metabolic changes are needed to serve better this population of patients.

Adipokine levels are associated with insulin resistance in antipsychotics users independently of BMI

BACKGROUND

The prevalence of obesity, metabolic syndrome and type 2 diabetes mellitus is increased among patients with severe mental disorders, and particularly use of second generation antipsychotic drugs is associated with metabolic side effects. Antipsychotics have been found to alter levels of adipokines which regulate insulin sensitivity, but their role in antipsychotic-associated insulin resistance is not established, and it is unclear whether adipokines affect insulin resistance independently of body mass index (BMI).

METHODS

We included 1050 patients with severe mental disorders and 112 healthy controls aged 18-65 years from the Oslo area, Norway. Clinical variables, BMI and use of medication were assessed, fasting blood samples were obtained for calculation of the leptin/adiponectin ratio (L/A ratio) and estimate of insulin resistance using the Homeostatic Model Assessment for Insulin Resistance (HOMA-IR). Case-control analyses were followed by mediation analyses to evaluate the possible direct effect of antipsychotics on HOMA-IR and indirect effect mediated via the L/A ratio. This was performed both with and without adjustment for BMI, in the total sample and in an antipsychotic monotherapy subsample (N = 387).

RESULTS

BMI, L/A ratio and HOMA-IR were significantly higher in patients than controls (p < 0.001-p = 0.01). There was a significant direct effect from use of antipsychotics in general on HOMA-IR both without (b = 0.03, p = 0.007) and with adjustment for BMI (b = 0.03, p = 0.013), as well as a significant mediating effect via L/A ratio both without (b = 0.03, p < 0.001) and with adjustment for BMI (b = 0.01, p = 0.041). Use of olanzapine (b = 0.03, p < 0.001) or aripiprazole (b = 0.04, p < 0.001) in monotherapy showed significant effects on HOMA-IR mediated via L/A ratio.

CONCLUSIONS

The study suggests that use of antipsychotics may alter adipokine levels, and that increased L/A ratio may play a role in the development of insulin resistance associated with use of antipsychotics also independently of BMI.

Free thyroxine and thyroid-stimulating hormone in severe mental disorders: A naturalistic study with focus on antipsychotic medication

BACKGROUND

Disturbances in thyroid function have been associated with use of psychotropic drugs, including antipsychotics. Still, the thyroid function in relation to commonly prescribed antipsychotic drugs and polypharmacy is not fully known. We investigated thyroid function associated with use of antipsychotics in patients with psychotic disorders compared with healthy controls.

METHODS

We included 1345 patients and 989 healthy controls from the Thematically Organized Psychosis (TOP) study, recruiting participants between 18 and 65 years of age in the Oslo-area. All patients underwent a thorough clinical investigation and assessment of medication data. Thyroid function was determined from plasma levels of free thyroxin (fT4) and thyroid-stimulating hormone (TSH). Multiple linear regression analyses were performed to evaluate the association between thyroid parameters and use of antipsychotics, and monotherapy users of olanzapine, quetiapine, aripiprazole or risperidone (N = 473) were investigated separately.

RESULTS

We found lower levels of fT4 (median 13.70 vs 14.00, p < 0.001) in patients compared to healthy controls, and a prevalence of 12.9% of previously undiagnosed deviant thyroid states in the patient group. Lower fT4 levels was associated with use of antipsychotics in general (p = 0.001), and quetiapine (p = 0.003) and olanzapine (p = 0.018) in particular, while the associations with TSH were non-significant. Using antipsychotics in combination with other psychotropic drugs, and with antidepressants in particular, was associated with lower fT4 level (p < 0.001) than use of antipsychotics alone.

CONCLUSIONS

Our findings indicate an association between use of antipsychotics and lower fT4. Clinicians should be aware that patients using quetiapine, olanzapine or antipsychotics in psychotropic polypharmacy are especially at risk.

Reduced heart rate variability in schizophrenia and bipolar disorder compared to healthy controls

OBJECTIVE

Despite current diagnostic systems distinguishing schizophrenia (SZ) and bipolar disorder (BD) as separate diseases, emerging evidence suggests they share a number of clinical and epidemiological features, such as increased cardiovascular disease (CVD) risk. It is not well understood if poor cardiac autonomic nervous system regulation, which can be indexed non-invasively by the calculation of heart rate variability (HRV), contributes to these common CVD risk factors in both diseases.

METHOD

We calculated HRV in 47 patients with SZ, 33 patients with BD and 212 healthy controls. Measures of symptom severity were also collected from the patient groups.

RESULTS

Heart rate variability was significantly reduced in both these disorders in comparison with the healthy participants; however, there were no HRV differences between disorders. Importantly, these reductions were independent of the medication, age or body mass index effects. There was also preliminary evidence that patients with reduced HRV had increased overall and negative psychosis symptom severity regardless of SZ or BD diagnosis.

CONCLUSION

We suggest that HRV may provide a possible biomarker of CVD risk and symptom severity in severe mental illness. Thus, our results highlight the importance of cardiometabolic screening across SZ and bipolar spectrum disorders.

Pharmacotherapy of bipolar disorder with quetiapine: a recent literature review and an update

Bipolar disorder is a chronic, recurrent condition with the usual onset during adolescence or early adulthood. In the Diagnostic and Statistical Manual of Mental Disorders 5th edition, it is conceptualized as a spectrum disorder usually associated with such comorbidities as anxiety disorders and substance use disorders. It is a relatively prevalent condition often complicated by mixed episodes, rapid cycling, subsyndromal symptoms, and treatment refractoriness. In spite of carrying substantial morbidity and mortality, effective treatments are few and far between and conventional mood stabilizers are often unsuccessful in controlling the various manifestations of the disorder. In this scenario, second generation antipsychotics are emerging as treatments with valid efficacy in all phases of bipolar disorder. Quetiapine is a versatile atypical antipsychotic which was first approved for the treatment of schizophrenia, but latter on the basis of controlled studies earned United States Food and Drug Administration’s approval for acute as well as maintenance treatment of this difficult to treat condition. In this review, recently published studies in the last 10 years were examined to update the knowledge about the efficacy and safety of quetiapine in the treatment of bipolar disorder. The medication’s clinical pharmacology was first considered followed by a literature review summarizing its uses in bipolar disorder. The conclusion was that quetiapine was efficacious in manic, mixed and depressive episodes and as a maintenance agent with a good tolerability profile.

Polygenic risk score and the psychosis continuum model

OBJECTIVE

Schizophrenia (SZ) and bipolar disorder (BD) are heritable, polygenic disorders with shared clinical characteristics and genetic risk indicating a psychosis continuum. This is the first study using polygenic risk score (PGRS) to investigate the localization of diagnostic subcategories along the entire psychosis spectrum.

METHOD

Based on results from the Psychiatric Genomics Consortium (PGC), we assigned a SZ and BD PGRS to each individual in our independent sample [N=570 BD spectrum cases, 452 SZ spectrum cases and 415 healthy controls (CTR)]. Potential differences in mean SZ and BD PGRS across diagnostic spectrums and subcategories were explored.

RESULTS

SZ and BD PGRSs were significantly associated with both SZ and BD spectrums compared with CTR. For the subcategories, SZ PGRS was significantly associated with SZ, schizoaffective disorder, psychosis not otherwise specified, and BD1, while BD PGRS was significantly associated with BD1 and BD2. There were no significant differences between any of the diagnostic spectrums or subgroups for neither the SZ nor BD PGRS. Lifetime psychosis was significantly associated with SZ PGRS but not with BD PGRS.

CONCLUSION

These findings further support the psychosis continuum model and provide molecular polygenetic validation of the localization of diagnostic subcategories within this continuum.

Indian Psychiatric Society multicentric study: Prescription patterns of psychotropics in India

BACKGROUND

There is a lack of national level data from India on prescription of psychotropics by psychiatrists.

AIM AND OBJECTIVE

This study aimed to assess the first prescription handed over to the psychiatrically ill patients whenever they contact a psychiatrist.

MATERIALS AND METHODS

Data were collected across 11 centers. Psychiatric diagnosis was made as per the International Classification of Diseases Classification of Mental and Behavioural Disorders 10(th) edition criteria based on Mini International Neuropsychiatric Interview, and the data of psychotropic prescriptions was collected.

RESULTS

Study included 4480 patients, slightly more than half of the subjects were of male (54.8%) and most of the participants were married (71.8%). Half of the participants were from the urban background, and about half (46.9%) were educated up to or beyond high school. The most common diagnostic category was that of affective disorders (54.3%), followed by Neurotic, stress-related and somatoform disorders (22.2%) and psychotic disorders (19.1%). Other diagnostic categories formed a very small proportion of the study participants. Among the antidepressants, most commonly prescribed antidepressant included escitalopram followed by sertraline. Escitalopram was the most common antidepressant across 7 out of 11 centers and second most common in three centers. Among the antipsychotics, the most commonly prescribed antipsychotic was olanzapine followed by risperidone. Olanzapine was the most commonly prescribed antipsychotic across 6 out of 11 centers and second most common antipsychotic across rest of the centers. Among the mood stabilizers valproate was prescribed more often, and it was the most commonly prescribed mood stabilizer in 8 out of 11 centers. Clonazepam was prescribed as anxiolytic about 5 times more commonly than lorazepam. Clonazepam was the most common benzodiazepine prescribed in 6 out of the 11 centers. Rate of polypharmacy was low.

CONCLUSION

Escitalopram is the most commonly prescribed antidepressant, olanzapine is the most commonly prescribed antipsychotic and clonazepam is most commonly prescribed benzodiazepine. There are very few variations in prescription patterns across various centers.

Drug safety evaluation of olanzapine/fluoxetine combination

INTRODUCTION

Bipolar disorder and treatment-resistant depression (TRD) are common and recurrent conditions associated with significant disability, morbidity and mortality. Despite the clear need for effective treatments, only a few medications have been approved in the US for these indications. The combined formulation of olanzapine-fluoxetine (OFC) has been available for a decade now, thus a review on its safety profile and comparative efficacy is timely and can help clinicians to determine the benefit/risk profile of OFC within the context of other treatment alternatives.

AREAS COVERED

This paper summarizes the rationale and evidence supporting the use of OFC for both bipolar I depressive episodes and TRD with a focus on safety and tolerability. Product labels and the search engine PubMed was used to obtain relevant information on this subject.

EXPERT OPINION

Although further comparative studies are needed, the literature confirms that the OFC is an effective treatment for bipolar I depressive episodes, as well as major depressive episodes that have not responded to several adequate courses of antidepressant therapy. Its use as a first-line treatment for bipolar I depressive episodes and at a higher rung of algorithms for patients with TRD is limited by its propensity to cause weight gain and associated metabolic symptoms.