The potential role of Marginal Structural Models (MSMs) in testing the effectiveness of antidepressants in the treatment of patients with major depression in everyday clinical practice.

OBJECTIVES: To better evaluate the effectiveness of antidepressant drugs in the treatment of major depression in clinical practice. METHODS: A simulation experiment was used to illustrate an application of marginal structural models (MSMs) via inverse probability of treatment weighting (IPTW) approach in the context of non-randomized data on N = 1,000 depressed subjects, initially subjected to "watchful waiting". In simulation we assumed that subjects with worse intermediate outcome have a higher probability of being subsequently assigned to antidepressant treatment while those who receive antidepressant treatment are more likely to reach remission and less likely to reach relapse state. The outcomes from multiple (500) simulated data sets are analyzed using simple unadjusted analysis based on logistic regression and using MSM. RESULTS: In contrast to unadjusted analysis, but consistent with the treatment assumptions, using MSM via IPTW results in strong evidence of the effectiveness of the antidepressant treatment. Furthermore MSM via IPTW substantially reduces the probability of wrongly rejecting the null hypothesis. However, the instability of weights due to the sparse data and incorrectly specified MSM may still result in inflation of Type I error rates. CONCLUSIONS: MSMs may allow evaluating the causal effects associated with antidepressant treatment from the data observed in clinical practice.

The Hypomania Checklist-32 and the Mood Disorder Questionnaire as screening tools--going beyond samples of purely mood-disordered patients.

BACKGROUND: Bipolar disorders are often not recognized. Several screening tools have been developed, e.g., the Hypomania Checklist-32 (HCL-32) and the Mood Disorder Questionnaire (MDQ) to improve this situation. Whereas the German HCL-32 has been used in non-clinical samples, neither the HCL-32 nor the MDQ has been validated in German samples of mood-disordered patients. Additionally, hardly any prior study has included patients with non-mood disorders or has considered potential effects of comorbid conditions. Therefore the goal of this study was to test the validity of both scales in a diverse patient sample while also taking into account psychiatric comorbidity. METHOD: A multi-site study was conducted involving seven centers. Patients (n=488) completed the HCL-32 and MDQ and were independently interviewed with the Structured Clinical Interview for DSM (SCID). RESULTS: Sensitivity for bipolar I was similar for HCL-32 and MDQ (.88 and .84) but slightly different for bipolar II (.90 and .83), specificity, however, was higher for MDQ. In general, a comorbid condition led to increased scores in both tools regardless of whether the primary diagnosis was bipolar or not. LIMITATIONS AND DISCUSSION: Although we included not just mood-disordered patients, detailed subgroup analyses for all diagnostic categories were not possible due to sample sizes. In summary, HCL-32 and MDQ seem fairly comparable in detecting bipolar disorders although their effectiveness depends on the goal of the screening, psychiatric comorbidity, and potentially the setting.

The impact of homocysteine levels on cognition in euthymic bipolar patients: a cross-sectional study.

OBJECTIVE: Bipolar disorder is associated with cognitive impairment. High homocysteine levels seem to have a negative impact on cognition in the elderly. The aim of the present study was to investigate the potential relationship of elevated homocysteine levels and cognitive impairment in bipolar patients. METHOD: Cognitive functioning of DSM-IV bipolar disorder patients who were euthymic (Hamilton Rating Scale for Depression score < or = 5 and Young Mania Rating Scale score < or = 5) and healthy controls was assessed with the revised Wechsler Adult Intelligence Scale Information Subtest, the Wechsler Adult Intelligence Scale III Letter-Number Sequencing Subtest, the Trail Making Test, and the Repeatable Battery for the Assessment of Neuropsychological Status Form A to examine premorbid IQ, information processing speed, working memory, verbal learning, visuospatial/constructional abilities, delayed memory, and executive functions. Total homocysteine plasma concentration was measured by using high-performance liquid chromatography. Multivariate analyses of variance and multiple regression analyses were conducted to examine group differences and possible associations between cognitive functioning and homocysteine level. The study was conducted from 2002 through 2006. RESULTS: Seventy-five euthymic bipolar patients and 42 healthy controls participated in the study. Patients performed significantly worse than controls in all cognitive domains tested (Pillai Spur: F = 3.32, p = .038) except premorbid IQ (p = .068). The mean +/- SD homocysteine levels were 10.2 +/- 3.2 microM/L for patients and 8.9 +/- 2.8 microM/L for controls (p = .036). Stepwise regression analyses revealed a significant and independent association of homocysteine levels with verbal learning (p = .002), delayed memory (p = .030), and executive function (p = .011) in the patient group. About 11% of the variance was explained by only the homocysteine level. CONCLUSIONS: Elevated homocysteine levels may have a negative impact on verbal learning, delayed memory, and executive function in euthymic bipolar patients, but further studies are warranted.

Impact of cognitive-psychoeducational interventions in bipolar patients and their relatives.

BACKGROUND: In recent years, several controlled studies could show that psychoeducational interventions have been effective for relapse prevention in bipolar disorders. We therefore established a cognitive-psychoeducational group intervention with 14 sessions providing information about the illness, early warning signs, cognitive and behavioural strategies for stress management and social rhythm. Additionally we offered a group intervention for the patients' relatives. The objective of this study was to describe the outcome associated with our psychoeducational intervention in bipolar patients and their relatives. METHODS: Sixty-two bipolar patients attended 14 sessions (à 90 min) of cognitive-psychoeducational group therapy. Patients' knowledge of bipolar disorder and their satisfaction with the treatment were assessed using self-developed questionnaires before and after the group intervention. Additionally, 49 relatives of bipolar patients received two psychoeducational workshops of 4 hours each. We assessed demographic variables, burden, high expressed emotion and depressive symptoms of the relatives before and after the two workshops and at 1-year follow-up. RESULTS: Patients significantly improved their knowledge of bipolar disorder. They also have benefited from the discussions and the exchange of useful coping strategies. Burden and high expressed emotions showed no significant reductions at post-assessment, however they were significantly reduced at 1-year follow-up. Relatives also felt significantly better informed about the illness. CONCLUSIONS: These findings show that psychoeducational interventions in bipolar patients and their relatives improve patients' and their relatives' knowledge of the illness and the burden of the disorder as well as high expressed emotions are reduced in relatives at 1-year follow-up.

The safety and tolerability of atypical antipsychotics in bipolar disorder.

Atypical antipsychotics (aAPs), have become a first-line treatment option, both in schizophrenia and bipolar disorders. Almost all aAPs now have proven efficacy in acute mania, some also in bipolar depression and in maintenance treatment. This provides reliable data on their safety and tolerability in this particular group of patients. This review focuses on the safety and tolerability of aAPs in the treatment of bipolar disorders. Both tolerability, for example, extrapyramidal symptoms, and safety issues, for example, occurrence of weight gain and hyperglycaemia, will be highlighted for olanzapine, quetiapine, risperidone, ziprasidone and aripiprazole.