Risk of adverse events with the use of augmentation therapy for the treatment of resistant depression

Augmentation of response and remission to serial intravenous subanesthetic ketamine in treatment resistant depression

BACKGROUND

Ketamine has been showing high efficacy and rapid antidepressant effect. However, studies of ketamine infusion wash subjects out from prior antidepressants, which may be impractical in routine practice. In this study, we determined antidepressant response and remission to six consecutive ketamine infusions while maintaining stable doses of antidepressant regimen. We also examined the trajectory of response and remission, and the time to relapse among responders.

METHODS

TRD subjects had at least 2-month period of stable dose of antidepressants. Subjects completed six IV infusions of 0.5mg/kg ketamine over 40min on a Monday-Wednesday-Friday schedule during a 12-day period participants meeting response criteria were monitored for relapse for 4 weeks.

RESULTS

Fourteen subjects were enrolled. Out of twelve subjects who completed all six infusions, eleven (91.6%) achieved response criterion while eight (66.6%) remitted. After the first infusion, only three and one out of twelve subjects responded and remitted, respectively. Four achieved response and six remitted after 3 or more infusions. Five out of eleven subjects remain in response status throughout the 4 weeks of follow-up. The mean time for six subjects who relapsed was 16 days.

LIMITATIONS

Small sample and lack of a placebo group limits the interpretation of efficacy.

CONCLUSIONS

Safety and efficacy of repeated ketamine infusions were attained without medication-free state in patients with TRD. Repeated infusions achieved superior antidepressant outcomes as compared to a single infusion with different trajectories of response and remission. Future studies are needed to elucidate neural circuits involved in treatment response to ketamine.

Prevalence and characteristics of antidepressant drug prescriptions in older Italian patients

BACKGROUND

During last few decades, the proportion of elderly persons prescribed with antidepressants for the treatment of depression and anxiety has increased. The aim of this study was to evaluate prevalence of antidepressant prescription and related factors in elderly in-patients, as well as the consistency between prescription of antidepressants and specific diagnoses requiring these medications.

METHODS

Thirty-four internal medicine and four geriatric wards in Italy participated in the Registro Politerapie SIMI-REPOSI study during 2008. In all, 1,155 in-patients, 65 years or older, were enrolled. Prevalence of the use of antidepressants was calculated at both admission and discharge. Logistic regression was used to evaluate the association between patients' characteristics (age, gender, Charlson Index, number of drugs, specific diseases, other psychotropic medications) and the prescription of antidepressants.

RESULTS

The number of patients treated with antidepressant medication at hospital admission was 115 (9.9%) and at discharge 119 (10.3%). In a multivariate analysis, a higher number of drugs (OR = 1.2; 95% CI = 1.1-1.3), use of anxiolytic drugs (OR = 2.1; 95% CI = 1.2-3.6 and OR = 3.8; 95% CI = 2.1-6.8), and a diagnosis of dementia (OR = 6.1; 95% CI = 3.1-11.8 and OR = 5.8; 95% CI = 3.3-10.3, respectively, at admission and discharge) were independently associated with antidepressant prescription. A specific diagnosis requiring the use of antidepressants was present only in 66 (57.4%) patients at admission and 76 (66.1%) at discharge.

CONCLUSIONS

Antidepressants are commonly prescribed in geriatric patients, especially in those receiving multiple drugs, other psychotropic drugs, and those affected by dementia. There is an inconsistency between the prescription of antidepressants and a specific diagnosis that the hospitalization only slightly improves.

Risk of adverse events in treatment-resistant depression: propensity-score-matched comparison of antidepressant augment and switch strategies

OBJECTIVE

The objective was to assess differences in adverse events between major depressive patients augmented with a second medication and patients switched to an alternative monotherapy after failing first-step treatment with citalopram.

METHOD

Adverse event profiles for second-step switch and augment medication strategies were compared using public data files from the Sequenced Treatment Alternatives to Relieve Depression (STAR*D) trial. In the STAR*D trial, participants failing citalopram selected acceptable next-step strategies and were randomized within acceptable strategies. This design resulted in clinically important differences when comparing across strategies, so a propensity-score-matched sample was created to compare switch (n=269) and augment (n=269) strategies.

RESULTS

Incidence proportions of any adverse event and specific adverse events were similar between the augment and switch groups. The overall incidence proportion of any distressing event was 0.78 [95% confidence interval (CI) 0.72-0.84] in the augment group and 0.80 (95% CI 0.74-0.85) in the switch group. This contrasts unmatched analyses where distressing adverse events were less common in the augment group than the switch group (risk ratio 0.85, 95% CI 0.81-0.90).

CONCLUSION

After adjusting for selection bias inherent in the STAR*D comparison of augment with switch, clinically meaningful differences in the adverse event profiles between these treatment strategies were not observed.

Antidepressant augmentation and combination in unipolar depression: strong guidance, weak foundations

Depression will be the second leading contributor to the global burden of disease by 2020. In Ireland, in 2009, 6061 people were hospitalised with depressive disorders. This represents a significant economic and social burden. There is growing awareness of the difficulty in treating depression with medications alone. The likelihood that a patient will achieve remission with the first antidepressant tried is around 30%, and the rates are similar for the second antidepressant tried. This falls to around 15% after three trials. Many patients are exposed to pharmacotherapy for extended periods of time with little beneficial effect, but often with side-effects. Patients are therefore in great need of clear information with regard to their chance of success. Clinicians are in need of clear guidance on prescribing strategies which have proven efficacy. However, this guidance often discusses treatment strategies based on varying levels of evidence. Guiding bodies may approach the problem from varying perspectives. The UK National Institute for Health and Clinical Excellence (NICE) has a clear government mandate with regard to provision of not only effective but cost-effective treatments. The British Association of Psychopharmacology (BAP) is an independent body of interested researchers and therefore may discuss prescribing options from the point of view of tertiary care institutions, and university centres. The South London and Maudsley NHS Foundation Trust publish the popular Maudsley guidelines. These are perhaps more pragmatic in nature, but include very low levels of evidence, including case series. The American Psychiatric Association (APA) is an independent member association which also publishes guidelines. These are published in the American Journal of Psychiatry and the latest guidelines were published in October 2010. All these bodies attempt to weigh their advice according to the level of evidence available and aim to provide clinical guidance in difficult situations. The burden on guiding organisations is to provide some direction and clarity in areas that are often unclear or controversial. Clinical guidelines are one method of providing support and guidance to busy clinicians. However, this clinician-centered approach has limitations. The onus is on the authors of the guidance to provide ever-more treatment options. This may mean that conclusions about the efficacy of medications is overstated or the limitations of the literature not fully explored in explanatory notes.

Therapeutic options for treatment-resistant depression

Treatment-resistant depression (TRD) presents major challenges for both patients and clinicians. There is no universally accepted definition of TRD, but results from the US National Institute of Mental Health's (NIMH) STAR*D (Sequenced Treatment Alternatives to Relieve Depression) programme indicate that after the failure of two treatment trials, the chances of remission decrease significantly. Several pharmacological and nonpharmacological treatments for TRD may be considered when optimized (adequate dose and duration) therapy has not produced a successful outcome and a patient is classified as resistant to treatment. Nonpharmacological strategies include psychotherapy (often in conjunction with pharmacotherapy), electroconvulsive therapy and vagus nerve stimulation. The US FDA recently approved vagus nerve stimulation as adjunctive therapy (after four prior treatment failures); however, its benefits are seen only after prolonged (up to 1 year) use. Other nonpharmacological options, such as repetitive transcranial stimulation, deep brain stimulation or psychosurgery, remain experimental and are not widely available. Pharmacological treatments of TRD can be grouped in two main categories: 'switching' or 'combining'. In the first, treatment is switched within and between classes of compounds. The benefits of switching include avoidance of polypharmacy, a narrower range of treatment-emergent adverse events and lower costs. An inherent disadvantage of any switching strategy is that partial treatment responses resulting from the initial treatment might be lost by its discontinuation in favour of another medication trial. Monotherapy switches have also been shown to have limited effectiveness in achieving remission. The advantage of combination strategies is the potential to build upon achieved improvements; they are generally recommended if partial response was achieved with the current treatment trial. Various non-antidepressant augmenting agents, such as lithium and thyroid hormones, are well studied, although not commonly used. There is also evidence of efficacy and increasing use of atypical antipsychotics in combination with antidepressants, for example, olanzapine in combination with fluoxetine (OFC) or augmentation with aripiprazole. The disadvantages of a combination strategy include multiple medications, a broader range of treatment-emergent adverse events and higher costs. Several experimental pharmaceutical treatment alternatives for TRD are also being explored in combination with antidepressants or as monotherapy. These less studied alternative compounds include pindolol, inositol, CNS stimulants, hormones, herbal supplements, omega-3 fatty acids, S-adenosyl-L-methionine, folic acid, lamotrigine, modafinil, riluzole and topiramate. In summary, despite an increasing variety of choices for the treatment of TRD, this condition remains universally undefined and represents an area of unmet medical need. There are few known approved pharmacological agents for TRD (aripiprazole and OFC) and overall outcomes remain poor. This might be an indication that depression itself is a heterogeneous condition with a great diversity of pathologies, highlighting the need for careful evaluation of individuals with depressive symptoms who are unresponsive to treatment. Clearly, more research is needed to provide clinicians with better guidance in making those treatment decisions--especially in light of accumulating evidence that the longer patients are unsuccessfully treated, the worse their long-term prognosis tends to be.

Lithium and venlafaxine interaction: a case of serotonin syndrome

Serotonin syndrome, which occurs as a result of enhanced serotonin concentration in the central nervous system, is a well-known adverse effect of serotonin-active medications. The concomitant use of antidepressant drugs associated with lithium as a co-adjuvant seems to increase the risk of this adverse reaction. We report a case of the serotonin syndrome during treatment with lithium and venlafaxine, an antidepressant with a dual selective re-uptake inhibition mechanism, and review the literature for similar cases. A 71-year-old woman developed serotonin syndrome while receiving treatment with moderate doses of lithium and venlafaxine for refractory depression. She had been taking higher doses of venlafaxine during the previous months with no significant secondary effects. Use of the Naranjo adverse drug reaction probability algorithm indicated a probable relationship between serotonin syndrome and treatment with lithium and venlafaxine.

Immediate switching of antidepressant therapy: results from a clinical trial of duloxetine

BACKGROUND

Approximately half of all treated depressed patients fail to show adequate response to their initially prescribed antidepressant medication. Switching to another medication represents one possible next-step approach for nonresponsive or partially responsive patients. However, specific techniques for switching between antidepressants have not been well studied. We examined the efficacy and tolerability associated with a switch from a selective serotonin reuptake inhibitor (SSRI) or venlafaxine to duloxetine.

METHODS

All patients met criteria for major depressive disorder as defined in DSM-IV. Patients (N = 88) exhibiting suboptimal response or poor tolerability to their current antidepressant medication (citalopram <or=40 mg/d, escitalopram <or=20 mg/d, fluvoxamine <or=150 mg/d, paroxetine <or=40 mg/d, sertraline <or=150 mg/d, or venlafaxine <or=150 mg/d) were switched to duloxetine 60 mg once-daily (QD) without intermediate tapering or titration ("switching" group). A comparator group (N = 67), comprising patients not currently receiving antidepressant medication, initiated duloxetine therapy at 60 mg QD ("initiating" group). Safety assessments included comparisons of discontinuation rates, treatment-emergent adverse events, and changes in vital signs. Efficacy measures included the HAMD(17), Hamilton Anxiety Scale (HAMA), and the Clinical Global Impression of Severity (CGI-S) scale.

RESULTS

The efficacy of duloxetine in switched patients did not differ significantly from that observed in untreated patients initiating duloxetine therapy (mean changes: HAMD(17) total score: -12.3 vs. -12.6; HAMA: -9.36 vs. -9.55, CGI-S: -1.94 vs. -2.12, respectively). However, the rate of discontinuation due to adverse events among patients switched to duloxetine was significantly lower than that in patients initiating duloxetine therapy (4.5% vs. 17.9%, p = .008). Treatment-emergent adverse events occurring in >or=10% of patients in both treatment groups were nausea, headache, dry mouth, insomnia, and diarrhea. Patients switched to duloxetine reported significantly lower rates of nausea and fatigue compared with patients initiating duloxetine.

CONCLUSIONS

In this study, the efficacy of duloxetine in switched patients was comparable to that observed in patients initiating duloxetine therapy. Immediate switching from an SSRI or venlafaxine to duloxetine (60 mg QD) was well tolerated.

Amantadine as augmentation therapy in the management of treatment-resistant depression

Treatment-resistant depression is an important clinical problem presenting a major challenge to clinical psychiatry. While several strategies have been attempted, including medication switch, antidepressant polypharmacy and various augmentative regimens, success remains limited. Amantadine (AMN), an agent traditionally used in the treatment and prophylaxis of influenza, is now known to exhibit prominent effects at the level of dopaminergic, monoamine oxidase and N-methyl-D-aspartate systems. The present reports on the efficacy of AMN as augmentation to standard antidepressant treatment in patients with treatment-resistant depression. Eight patients with treatment-resistant depression consented to receive AMN, titrated up to a dose of 300 mg, over a period of 4 weeks in a non-blinded fashion. Improvement in both depression and anxiety scores were observed from week 1, with patients exhibiting improvement of depressive scores of up to 49% by study completion. Females appeared to exhibit a stronger response, and within a shorter period of time. Side-effects reported included dry mouth and sedation. AMN appears to demonstrate efficacy as a safe and effective augmentative agent in treatment-resistant depression. Further studies are clearly mandated to test these preliminary observations in a double-blinded manner.

Co-prescribing of SSRIs and TCAs in Australia: how often does it occur and who is doing it?

AIMS

To determine the frequency with which the selective serotonin re-uptake inhibitor (SSRI) antidepressants are used as add-on therapy to the tricyclic antidepressants (TCA) rather than as replacement therapy.

METHODS

The data analysed were profiles of prescription records by date of supply to the patient. From within the national administrative dispensing claims database, the subset eligible for social security entitlements was identified as individuals by means of their coded permanent identification numbers (PINs). Following the initial supply of an SSRI in January 1996, the subsequent 6 months dispensing of SSRI and TCA antidepressants to these individuals was examined. The main outcome measure was the proportion of individuals to whom SSRIs and TCAs were dispensed concurrently, as an indirect measure of coprescription. In instances where a patient was receiving prescriptions for SSRIs and TCAs that had been written by the one doctor only, the major specialty of the doctor was investigated.

RESULTS

55 271 PINs were dispensed 63 865 SSRI prescriptions in January 1996 which represented over half (52%) of the total community SSRI prescriptions dispensed in that month. The number of these patients meeting the criteria for coprescription of SSRIs and TCAs over the next 6 months was 2773 (5%). The coprescribing instances were highest in Queensland and the prescribers most frequently involved had psychiatry major specialty codes.

CONCLUSIONS

Among SSRI users there is a cohort of patients who, within the same time frame, are receiving supplies of a TCA, the nonselective drug that the SSRIs were designed to replace. This is indirect evidence of probable coprescription. Such combination use is of uncertain clinical and cost effectiveness, and carries additional risks. The SSRIs were included on the subsidy list in Australia on the basis of reasonable cost effectiveness as monotherapy compared with the TCAs. Our data imply that for some patients, antidepressant prescribing is inconsistent with the basis on which government subsidy was approved.

Antidepressant augmentation and combinations

A significant proportion of patients with MDD are treatment resistant or only partial responders to adequate therapy with a single agent. In this situation, one must consider augmentation with another agent. Lithium and thyroid augmentation have been investigated for many years. In a meta-analysis of double-blind studies involving augmentation with lithium or placebo after nonresponse to conventional antidepressants, lithium augmentation was concluded to be the first-line therapy for depressed patients who failed to respond to monotherapy. One important study reported no significant difference in response rates between T3 and lithium as augmentation agents in patients who had failed to respond to TCAs. Very few controlled, double-blind trials show consistently positive results for the other augmentation strategies, although some open-labeled trials and case reports are promising. Additional placebo-controlled, double-blind studies are needed to assess the efficacy and tolerability of all of these agents, especially in combination with the newer classes of antidepressants.

[Serotonin syndrome associated to the use of paroxetine. Case report]

We report on a case of serotonin syndrome associated to the use of the paroxetine, a serotonin reuptake inhibitor drug. Serotonin syndrome related to this drug not combined with other drugs had not yet been described in literature.