понедельник, 30 мая 2011 г.

Метирапон и психотравмирующие воспоминания

“Metyrapone is a drug that significantly decreases the levels of cortisol, a stress hormone that is involved in memory recall,” explained lead author Marie-France Marin, a doctoral student.

Manipulating cortisol close to the time of forming new memories can decrease the negative emotions that may be associated with them, the researchers said.

“The results show that when we decrease stress hormone levels at the time of recall of a negative event, we can impair the memory for this negative event with a long-lasting effect,” said Sonia Lupien, Ph.D., who directed the research.

The Drug Metyrapone to Erase Bad Memories?

понедельник, 23 мая 2011 г.

Индивидуальные различия в ответе на терапию оланзапином

The antipsychotic drug, olanzapine, one of the most widely used drugs in clinical medicine, has a high rate of discontinuation due to inefficacy and/or adverse effects. We identified a single nucleotide polymorphism in the drug metabolizing enzyme, cytochrome P450 3A43 (CYP3A43; rs472660), that highly significantly predicted olanzapine clearance in the Clinical Antipsychotic Trials of Intervention Effectiveness trial (P=5.9e−7). Moreover, at standard antipsychotic doses, 50% of individuals with the high clearance genotype (AA) have trough blood levels below the therapeutic range. Interestingly, a much higher proportion of African Americans carry the A allele compared with Caucasians (allele frequency 67 vs 14%). After accounting for CYP3A43 genotype, race is no longer a significant predictor of olanzapine clearance. Olanzapine clearance was associated with measures of clinical response. Patients with greater clearance had higher symptom ratings and were more likely to discontinue treatment due to an inadequate response. Our data identify a genetic mechanism for variation in olanzapine response and demonstrate that blood level monitoring of olanzapine treatment is advisable.

Genetic variation in CYP3A43 explains racial difference in olanzapine clearance

среда, 18 мая 2011 г.

Лекарственные средства вызывающие депрессию

Interferons are powerful antivirals but they have the dubious honor of being one of the few medical drugs clearly implicated in causing depression. Others include reserpine, an anti-hypertensive and rimonabant, a weight-loss drug (it got banned for this reason).

The anti-malarial mefloquine can cause a range of neuropsychiatric symptoms including depression but also hallucinations and nightmares, as can the HIV drug efavirenz which I covered recently.

Most people who take each of these drugs don't experience problems but in a non-trivial minority it happens. It obviously poses a serious problem for doctors, but it's also very interesting for people researching mood and depression. Work out why these drugs cause depression, and it might help work out why people get "normal" clinical depression.

For example, just recently it was shown that mefloquine has a unique and unusual effect on cells in the dopamine system of the brain, responsible for motivation and pleasure. Whether this explains the side-effects is an open question but without mefloquine we wouldn't even be able to ask it.

As for interferons, which are actually not drugs as such but rather molecules produced by the immune system during infections, it's given rise to the inflammation theory of depression. There's always a risk, though, that by focussing too much on just one class of depressing drug, you'll end up with a narrow theory that can't account for the others.

Antivirals and Suicide

Социальное функционирование при долгосрочном приёме антипсихотиков, преимущества оланзапина

Background
When treating schizophrenia, improving patients' productivity level is a major goal considering schizophrenia is a leading cause of functional disability. Productivity level has been identified as the most preferred treatment outcome by patients with schizophrenia. However, little has been done to systematically investigate productivity levels in schizophrenia. We set out to better understand the change in productivity level among chronically ill patients with schizophrenia treated with olanzapine compared with other antipsychotic medications. We also assessed the links between productivity level and other clinical outcomes.

Methods
This post hoc analysis used data from 6 randomized, double-blind clinical trials of patients with schizophrenia or schizoaffective disorder, with each trial being of approximately 6 months duration. Change in productivity level was compared between olanzapine-treated patients (HGBG, n=172; HGHJ, n=277; HGJB, n=171; HGLB, n=281; HGGN, n=159; HGDH, n=131) and patients treated with other antipsychotic medications (separately vs. haloperidol [HGGN, n=97; HGDH, n=132], risperidone [HGBG, n=167; HGGN, n=158], quetiapine [HGJB, n=175], ziprasidone [HGHJ, n=271] and aripiprazole [HGLB, n=285]). Productivity was defined as functional activities/work including working for pay, studying, housekeeping and volunteer work. Productivity level in the prior 3 months was assessed on a 5-point scale ranging from no useful functioning to functional activity/work 75% to 100% of the time.

Results
Chronically ill patients treated with olanzapine (OLZ) experienced significantly greater improvement in productivity when compared to patients treated with risperidone (RISP) (OLZ= 0.22+/-1.19, RISP=-0.03+/-1.17, p=0.033) or ziprasidone (ZIP) (OLZ=0.50+/-1.38, ZIP=0.25+/-1.27, p=0.026), but did not significantly differ from the ziprasidone, quetiapine, aripiprazole or haloperidol treatment groups. Among first episode patients, OLZ therapy was associated with greater improvements in productivity levels compared to haloperidol (HAL), during the acute phase (OLZ=-0.31+/-1.59, HAL=-0.69+/-1.56, p=0.011) and over the long-term (OLZ=0.10+/-1.50, HAL=-0.32+/-1.91, p=0.008). Significantly more chronically ill and first episode patients treated with olanzapine showed moderately high (>50%-75% of the time) and high levels of productivity (>75%-100% of the time) at endpoint, when compared to risperidone- or haloperidol-treated patients (p<.05), respectively. Higher productivity level was associated with significantly higher study completion rates and better scores on the positive, negative, disorganized thoughts, hostility and depression subscales of the Positive and Negative Symptom Scale (PANSS).

Conclusions
Some antipsychotic medications significantly differed in beneficial impact on productivity level in the long-term treatment of patients with schizophrenia. Findings further highlight the link between clinical and functional outcomes, showing significant associations between higher productivity, lower symptom severity and better persistence on therapy. TRIAL REGISTRATION: clinicaltrials.gov identifier NCT00088049; NCT00036088

Change in Level of Productivity in the Treatment of Schizophrenia with Olanzapine or Other Antipsychotics

вторник, 10 мая 2011 г.

Нейропсихиатрические побочные эффекты варениклина

Background

Varenicline is an α4β2 partial nicotinic agonist approved for smoking cessation. There have been spontaneous postmarketing reports of neuropsychiatric adverse events (NPAEs) in smokers without a history of psychiatric illness quitting with varenicline.

Methods

One hundred ten smokers without history of psychiatric illness (screened by Structured Clinical Interview for DSM-IV) were randomized to 12 weeks of varenicline 1 mg twice daily (n = 55) or placebo. Adverse events were solicited systematically. Depressive symptoms, anxiety, aggression, and irritability were measured at baseline and weekly using the Montgomery-Åsberg Depression Rating Scale (MADRS), the Hamilton Anxiety Scale (HAM-A), and the Overt Aggression Scale—Modified (OAS-M). The Profile of Mood States (POMS) was administered daily. Mixed-model analysis of repeated measures was conducted to compare mean changes in scores between groups across study periods.

Results

Participants' mean baseline characteristics were 33 years of age, 22 cigarettes/day and Fagerström Test for Nicotine Dependence score > 7. Reported NPAEs were similar between groups. No suicidal events were reported. There were no significant differences between groups for the MADRS (treatment difference vs. placebo = .03, 95% confidence interval [CI] −.68–.73; NS), HAM-A (treatment difference [TD] = .14, 95% CI −.62–.90; NS), OAS-M Aggression subscale (TD = .5, 95% CI −1.18–2.18; NS), OAS-M Irritability subscale (TD = .08, 95% CI −.17–.34; NS), and the POMS total scores (TD = .5, 95% CI −.52–1.53; NS).

Conclusions

There were no significant differences between groups on measures of depressive symptoms, anxiety, or aggression/hostility. Systematically solicited NPAEs were similar between the varenicline and placebo groups.

A Double-Blind Randomized Placebo-Controlled Pilot Study of Neuropsychiatric Adverse Events in Abstinent Smokers Treated with Varenicline or Placebo

среда, 4 мая 2011 г.

Комбинации антидепрессантов не превосходят по эффективности монотерапию антидепрессантом

The first group took escitalopram (a selective serotonin reuptake inhibitor, or SSRI, brand name Lexapro) and a placebo; the second group received the same SSRI along with bupropion (a non-tricyclic antidepressant, brand name Wellbutrin); and the third group took two different antidepressants: venlafaxine (a tetracyclic antidepressant, Effexor) and mirtazapine (a serotonin norepinephrine reuptake inhibitor, Remeron).

After 12 weeks of treatment, all three groups showed similar remission and response rates: 39 percent, 39 percent and 38 percent, respectively, for remission; response rates were approximately 52 percent in all three groups. After seven months, remission and response rates remained similar in all three groups, but side effects were more frequent in the third group.

Two Antidepressants Appear No Better Than One

вторник, 3 мая 2011 г.

Влияние нестероидных противовоспалительных средств на антидепрессивное действие СИОЗС

Cytokines may be important in depression. These immunomodulators are produced by glial cells, regulate brain serotonin and noradrenergic systems, and activate the hypothalamic-pituitary-adrenal axis. Antidepressants increase levels of p11, a specific protein that regulates depression in rodent models and interacts with the serotonin receptor. To learn about possible interactions of antidepressants, cytokines, p11, and anti-inflammatory drugs (NSAIDs), researchers conducted experiments in mice and reanalyzed data from the large STAR*D study.

The selective serotonin reuptake inhibitors citalopram and fluoxetine increased p11 levels in mouse frontal cortex, but coadministered ibuprofen (IBU) or acetylsalicylic acid (ASA) blocked this increase. IBU lowered plasma citalopram levels. The tricyclic desipramine produced a small p11 increase, which was not affected by IBU or ASA. Antidepressant-related p11 increases were dependent on signaling by two cytokines (interferon-gamma and tumor necrosis factor-alpha). In a mouse model of depression, IBU, ASA, and acetaminophen prevented the behavioral response to SSRIs but not to antidepressants of other types.

Of STAR*D patients who took citalopram for 12 weeks, significantly fewer achieved remission if taking NSAIDs than if not taking NSAIDs (45% vs. 55%). Findings were similar in a comparison of other analgesic use with nonuse (37% vs. 54%).

Do Analgesics Interfere with Efficacy of Selective Serotonin Reuptake Inhibitors?