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Prescriptions for antidepressants in a population of psychiatrists and non-psychiatrists
OBJECTIVE: Much proof has been accumulated over the last decade demonstrating that depression is a major public health issue. Use of psychotropics and more precisely antidepressants is considered to be excessive. It is however paradoxical that prescribing antidepressants has become commonplace. The aim of this study was to better assess the process of prescribing antidepressants in the hospital setting. METHODS: An epidemiological study was carried out to examine prescribing practices used by psychiatrists and non psychiatrists working in the Rennes University Hospital. The psychiatrist population was used as the reference population for univariate and multivariate analysis designed to ascertain differences concerning prescription practices. RESULTS: Duration of the clinical examination (shortest for non-psychiatric physicians, p = 0.0001), use of a diagnostic scale (more frequently for psychiatrists, p = 0.0008), reasons for choosing an antidepressant (pharmacological considerations more frequent among psychiatrists, p = 0.0009), and co-therapies (neuroleptic association more frequent among psychiatrists, p = 0.0001) were found to be different between the two prescribing populations. CONCLUSION: All patients with signs of depression are not necessarily given optimal care. Errors in assessing antidepressants is probably a common problem.
Activation of the TrkB neurotrophin receptor is induced by antidepressant drugs and is required for antidepressant-induced behavioral effects.
Recent studies have indicated that exogenously administered neurotrophins produce antidepressant-like behavioral effects. We have here investigated the role of endogenous brain-derived neurotrophic factor (BDNF) and its receptor trkB in the mechanism of action of antidepressant drugs. We found that trkB.T1-overexpressing transgenic mice, which show reduced trkB activation in brain, as well as heterozygous BDNF null (BDNF(+/)-) mice, were resistant to the effects of antidepressants in the forced swim test, indicating that normal trkB signaling is required for the behavioral effects typically produced by antidepressants. In contrast, neurotrophin-3(+/)- mice showed a normal behavioral response to antidepressants. Furthermore, acute as well as chronic antidepressant treatment induced autophosphorylation and activation of trkB in cerebral cortex, particularly in the prefrontal and anterior cingulate cortex and hippocampus. Tyrosines in the trkB autophosphorylation site were phosphorylated in response to antidepressants, but phosphorylation of the shc binding site was not observed. Nevertheless, phosphorylation of cAMP response element-binding protein was increased by antidepressants in the prefrontal cortex concomitantly with trkB phosphorylation and this response was reduced in trkB.T1-overexpressing mice. Our data suggest that antidepressants acutely increase trkB signaling in a BDNF-dependent manner in cerebral cortex and that this signaling is required for the behavioral effects typical of antidepressant drugs. Neurotrophin signaling increased by antidepressants may induce formation and stabilization of synaptic connectivity, which gradually leads to the clinical antidepressive effects and mood recovery.
Long-term treatment with antidepressants increases glucocorticoid receptor binding and gene expression in cultured rat hippocampal neurones.
Since the glucocorticoid receptor (GR) and/or mineralocorticoid receptor (MR) in the hippocampus have been implicated in cortisol feedback of the hypothalamus-pituitary-adrenal (HPA) axis, abnormalities in those receptors might underlie the hyperactivity of the HPA axis described in patients with major depression. Animal studies have shown that long-term in-vivo treatment with antidepressants up-regulates hippocampal GR and/or MR, but it is not clear whether this up-regulation is evoked through a direct action of antidepressants on these receptors. We therefore examined the direct effects of long-term antidepressant treatment on GR binding and the levels of GR messenger RNA (mRNA) in primary cultures of rat hippocampal neurones. The time course of the effects of the tricyclic antidepressants desipramine and Amitriptyline ( Elavil ) on GR binding, as assessed by dexamethasone binding using RU 28362, a specific agonist for GR, showed a biphasic mode of stimulation: desipramine significantly increased the GR binding with 2-day exposure by 36% over that in controls and by 99% and 60% with 10- and 14-day exposures, respectively. Amitriptyline ( Elavil ) also led to a significant increase in GR binding, with peaks at 2 (by 60%) and 14 days of exposure (by 60%). The effects of 14-day treatment with desipramine required at least the first 4-day exposure, and the first 10-day exposure was required for the full effect. Northern blot analysis demonstrated that the GR mRNA level was significantly increased by 14-day treatment with desipramine (+142% over control), Amitriptyline ( Elavil ) (+108%), mianserin (+124%), Paroxetine ( Paxil ) (+42%) and sulpiride (+92%), but not with haloperidol. Immunocytochemistry for GR revealed that 2- or 14-day treatment with desipramine significantly increased the number of GR-positive cells with dominant immunoreactivity in the nuclei of granule cell-like neurones or in perikarya of pyramidal cell- and granule cell-like neurones. These findings suggest that tricyclic antidepressants directly increase hippocampal GR by short-term (2-day) and long-term (14-day) exposure, and that the increase by long-term exposure is evoked commonly with different classes of antidepressants through transcriptional up-regulation of GR expression.
Electrophysiologic analysis of antidepressant drug effects on the GABA(A) receptor complex based upon antagonist-induced encephalographic power spectrum changes.
To better understand antidepressant drug effects on the GABA(A) receptor complex (the GABA(A) receptor, chloride ionophore and benzodiazepine receptor), we investigated how antidepressants influenced power spectrum changes induced by pentylenetetrazol (PTZ), a chloride ionophore antagonist, in the rat hippocampal electroencephalogram (EEG). In control recording, PTZ (27.5 mg/kg i. p.) increased EEG power at frequencies under 12 Hz up to five times. After rats were pretreated with imipramine, Fluoxetine ( Prozac ) or trazodone for 7 days (10 mg/kg i.p., twice a day), PTZ could not increase EEG power to more than three times the power before injection; this effect was not observed after pretreatment for 3 days. These three antidepressants inhibit serotonin uptake, while two other antidepressants, desipramine and nortriptyline, that inhibit norepinephrine uptake failed to counter the PTZ effect. We concluded that antidepressants with serotonergic effects enhanced the function of the GABA(A) receptor complex.
Selection of antidepressant drugs in general practice.
Depression is a common psychiatric illness and since majority of patients suffering from depression are first seen and treated by general practitioners, it is important for them to identify and treat depressive illness more effectively. Fortunately, depression is a treatable condition. Identifying the optimal antidepressant agent requires careful consideration of the patient's age, health status, and history of response to antidepressants. Other considerations include adverse effect profile, cost of drug therapy and convenient dosage schedule. Selective serotonin reuptake inhibitors are well tolerated and are considered by many to be the agents of choice in primary care treatment of depression because of their favourable adverse effect profile. Heterocyclic antidepressants are preferred in elderly patients and patients with medical problems. Tricyclic antidepressants can also be of great help specially to younger group of patients and patients who have failed to respond to other antidepressants.
Relative risk of vaginal candidiasis after use of antibiotics compared with antidepressants in women: postmarketing surveillance data in England.
BACKGROUND: Vaginal candidiasis is a common infection in women. The microflora of the vagina are influenced by a number of factors, including pregnancy, oral contraceptive use, menses and diabetes mellitus. Previous antibiotic use is generally accepted to be a risk factor for vaginal candidiasis but the published evidence to support this is limited.Aim: To determine the relative risk of vaginal candidiasis following the use of antibiotics compared with antidepressants in prescription-event monitoring (PEM) studies. METHODS: Using data from postmarketing surveillance studies of six antibiotics and six antidepressants, conducted using the observational cohort technique of PEM, the number of reports of vaginal candidiasis was determined in women aged > or =16 years, in each of the first 7 weeks following a prescription for one of these drugs. The relative risks for vaginal candidiasis following the use of these antibiotics and for each of the individual antibiotics compared with antidepressants were calculated for each week and for the overall 7-week period. Women treated with antidepressants were the most suitable comparator group from the PEM database, as they were of a similar age range and the studies were conducted at a similar time period to those of the antibiotics. Also, there was no pharmacological plausibility for vaginal candidiasis being associated with antidepressants. RESULTS: There were 188 reports of vaginal candidiasis in 31 588 women, aged > or =16 years, treated with antibiotics and 70 in the 45 492 treated with antidepressants. The relative risk for vaginal candidiasis (antibiotic/antidepressants), was highest in the second week, 10.70 (95% CI 4.86-23.55) but was also significantly greater in the first and third weeks after the start of treatment. The risk was also higher in each of the 3 weeks after starting the course for five of the antibiotics, compared individually to the group treated with antidepressants, the exception being fosfomycin, which had a much smaller cohort. CONCLUSION: This study shows a significant increase in the risk of developing vaginal candidiasis following the use of the antibiotics studied (ciprofloxacin, ofloxacin, norfloxacin, cefixime, azithromycin and fosfomycin) compared with that after taking the antidepressants fluvoxamine, Fluoxetine ( Prozac ), Paroxetine ( Paxil ), Sertraline HCL ( Zoloft ), Venlafaxine ( Effexor ) and nefazodine in these PEM studies.
An investigation of monoamine receptors involved in antinociceptive effects of antidepressants.
We attempted to determine which monoamine receptor subtypes are predominantly involved in antidepressant-induced antinociception. Antinociceptive effects were evaluated by using formalin tests with rats. antidepressants acting as potent inhibitors of norepinephrine reuptake (nisoxetine, nortriptyline, and maprotiline) or inhibiting reuptake of both norepinephrine and serotonin (5-HT) (imipramine and milnacipran) induced dose-dependent antinociception. Simultaneous intraperitoneal administration of antidepressants and either prazosin (alpha(1) antagonist) or ketanserin (5-HT(2) antagonist) significantly antagonized antinociceptive effects. Fluvoxamine (selective serotonin reuptake inhibitor) induced antinociception less potently than other antidepressants and was significantly antagonized by ketanserin, but not prazosin. Ondansetron (5-HT(3) antagonist) significantly antagonized antinociception by 10 mg/kg of imipramine. In contrast, SDZ-205,557 (5-HT(4) antagonist) markedly enhanced antinociception by small-dose (2.5 mg/kg) imipramine. Imipramine-induced antinociception was significantly antagonized by intracerebroventricular administration of prazosin or ketanserin, but not by yohimbine (alpha(2) antagonist) or ondansetron, and was significantly enhanced by intracerebroventricularly administered SDZ-205,557. These findings suggest that alpha(1) adrenoceptors and 5-HT(2) receptors in the brain are involved in antidepressant-induced antinociception. In addition, the results suggested functional interactions between noradrenergic and serotonergic neurons as mechanisms for antidepressant-induced antinociception. IMPLICATIONS: Formalin tests of rats treated with antidepressants and antagonists of monoamine receptors indicate that alpha(1) adrenoceptors, serotonin (5-HT)(2) receptors, and 5-HT(3) receptors are involved in antidepressant-induced antinociception, suggesting functional interactions between noradrenergic and serotonergic neurons as mechanisms of antidepressant-induced antinociception.
Counseling versus antidepressant therapy for the treatment of mild to moderate depression in primary care: economic analysis.
OBJECTIVE: To compare the cost-effectiveness of generic psychological therapy (counseling) with routinely prescribed antidepressant drugs in a naturalistic general practice setting for a follow-up period of 12 months. METHODs: Economic analysis alongside a randomized clinical trial with patient preference arm. Comparison of depression-related health service costs at 12 months. Cost-effectiveness analysis of bootstrapped trial data using net monetary benefits and acceptability curves. RESULTS: No significant difference between the mean observed costs of patients randomized to antidepressants or to counseling (342 pounds sterling vs 302 pounds sterling , p = .56 [t test]). If decision makers are not willing to pay more for additional benefits (value placed on extra patient with good outcome, denoted by K, is zero), then we find little difference between the treatment modalities in terms of cost-effectiveness. If decision makers do place value on additional benefit (K > 0 pounds sterling), then the antidepressant group becomes more likely to be cost-effective. This likelihood is in excess of 90% where decision makers are prepared to pay an additional 2,000 pounds sterling or more per additional patient with a good global outcome. The mean values for incremental net monetary benefits (INMB) from antidepressants are substantial for higher values of K (INMB = 406 pounds sterling when K = 2,500 pounds sterling). CONCLUSION: For a small proportion of patients, the counseling intervention (as specified in this trial) is a dominant cost-effective strategy. For a larger proportion of patients, the antidepressant intervention (as specified in this trial) is the dominant cost-effective strategy. For the remaining group of patients, cost-effectiveness depends on the value of K. Since we cannot observe K, acceptability curves are a useful way to inform decision makers.
Serotonergic antidepressants are associated with REM sleep without atonia.
STUDY OBJECTIVES: Rapid eye movement (REM) sleep behavior disorder (RBD) is generally observed in older men and in individuals with specific neurologic diseases. There are case reports of RBD in individuals taking serotonergic antidepressants. Our objective was to assess electromyogram (EMG) activity during REM sleep in individuals taking serotonergic antidepressants and in a matched control group not on such medication. DESIGN: Chart review of clinical and polysomnographic data. SETTING: Sleep laboratory affiliated with a general hospital. PARTICIPANTS: 15 subjects taking a serotonergic antidepressant and 15 age-matched individuals not on such medication. MEASUREMENTS: Submental and anterior tibialis tonic and phasic EMG activity during REM sleep, REM latency, time in REM, apnea-hypopnea index, periodic leg movements of sleep index, and sleep-architecture measures. RESULTS: Tonic, but not phasic, submental EMG activity during REM sleep was significantly more common in the antidepressant-treated group than in the control group (P < .02). Tonic REM submental EMG activity correlated with REM latency (r = .42, P = .02) and inversely with REM time (r = -.36, P = .05). Subject age correlated with tonic REM submental EMG activity (r = .58, P = .02) in the antidepressant group There were also trends for more phasic activity in the anterior tibialis (P = .09) and submental (P = .07) EMG in REM sleep in the antidepressant group than in the control group. CONCLUSIONS: Subjects taking serotonergic antidepressants had more EMG activity in the submental lead during REM sleep than did controls. This correlated with measures of REM suppression and age. Individuals taking such medications may be at increased risk of developing REM sleep behavior disorder, particularly with increasing age.
Racial variation in antidepressant treatment in a Medicaid population.
BACKGROUND: Many studies have found racial and socioeconomic variation in medical care for a variety of conditions. Undertreatment of depression for individuals of all races is a concern, but especially may affect vulnerable populations such as Medicaid recipients and minorities. With this study, we examine racial differences in the antidepressant usage in a Medicaid population. METHOD: Treatment of 13,065 depressed patients (ICD-9-CM criteria) was examined in a state Medicaid database covering the years 1989 through 1994. Treatment differences were assessed in terms of whether an antidepressant was received at the time of the initial depression diagnosis and the type of antidepressant prescribed (tricyclic antidepressants [TCAs] vs. selective serotonin reuptake inhibitors [SSRIs]), using logistic regression techniques. RESULTS: African Americans were less likely than whites to receive an antidepressant at the time of their initial depression diagnosis (27.2% vs. 44.0%, p < .001). Of those receiving an antidepressant, whites were more likely than African Americans to receive SSRIs versus TCAs. These findings remained even after adjusting for other covariates. CONCLUSION: Despite the easy availability of effective treatments, we found that only a small portion of depressed Medicaid recipients receive adequate usage of antidepressants. Within this Medicaid population, limited access to treatment was especially pronounced among African Americans. Racial differences existed in terms of whether an antidepressant was received and the type of medication used.
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