R347C Polymorphisms in ADRA1A Genes and Mirtazapine Treatment Response in Koreans with Major Depression

OBJECTIVES: Adrenergic alpha 1 and 2 receptors work as pathways to control the serotonergic neuron moderation and mirtazapine acts as antagonist of these receptors. The adrenoreceptor alpha 1a (ADRA1A) gene, which encodes adrenergic alpha 1 receptor, has Arg347Cys genetic polymorphism and the polymorphism has strong relationship with many neuro-psychiatric diseases. In this study, we explored the relationship between ADRA1A R347C polymorphism and mirtazapine treatment response in Koreans with major depression. METHODS: 352 patients enrolled in this study, and the symptoms were evaluated by 17-item Hamilton Depression Rating (HAMD-17) scale. After 1, 2, 4, 8, and 12 weeks of mirtazapine treatment, the association between ADRA1A R347C polymorphism and remission/response outcomes was evaluated. RESULTS: Treatment response to mirtazapine was significantly better in T allele carriers than C allele homozygotes after 12 weeks of mirtazapine monotherapy. The percentile decline of HAMD-17 score in T allele carriers was larger than that of C allele homozygotes. ADRA1A R347C genotypes were not significantly associated with remission. CONCLUSIONS: The result showed that treatment response to mirtazapine was significantly associated with ADRA1A R347C genetic polymorphism. T allele carriers showed better treatment response than C allele homozygotes. It can be supposed that T allele carriers have a trend of better treatment response to mirtazapine monotherapy.

Evidence-Based Korean Pharmacological Treatment Guideline for Depression, Revised Edition (II) : Antidepressant Efficacy Compared with Placebo, Difference in Efficacy of Antidepressants, and Appropriate Time of Efficacy Judgment in Antidepressant Therapy / 신경정신의학

OBJECTIVES: The purpose of this study was to suggest recommendations of antidepressant efficacy compared with placebo, difference in efficacy of antidepressants, and appropriate time of efficacy judgment in antidepressant therapy. METHODS: Using recommendations from 12 international and domestic clinical practice guidelines for depression, drawing of recommendation drafts, and peer review, the executive committee developed the guideline. RESULTS: Tricyclic antidepressants (TCAs), monoamine oxidase inhibitors (MAOI), selective serotonin reuptake inhibitors (SSRI), serotonin and norepinephrine reuptake inhibitors (SNRIs), norepinephrine and specific serotonergic antidepressants (NaSSAs), norepinephrine and dopamine reuptake inhibitors (NDRIs), and serotonin antagonist and reuptake inhibitors (SARIs) were strongly recommended as having antidepressant efficacy compared with placebo. Difference in efficacy of antidepressants was as follows. TCAs, MAOI, SSRI, SNRIs, and NaSSAs were strongly recommended, however, NDRIs, SARIs were weakly recommended. If there was no or minimal improvement with treatment, appropriate time of efficacy judgment in antidepressant therapy was estimated to be after two to four weeks. CONCLUSION: We hope that the results of this study will be helpful in encouraging the optimal treatment by understanding antidepressant efficacy compared with placebo, difference in efficacy of antidepressants, and appropriate time of efficacy judgment in antidepressant therapy.

Evidence-Based Korean Pharmacological Treatment Guideline for Depression, Revised Edition (III) : Dose Increment, Switching, Combination, and Augmentation Strategy in Antidepressant Therapy / 신경정신의학

OBJECTIVES: The aim of this study was to demonstrate the recommendations for antidepressant treatment strategy of dose increment, switching, combination, and augmentation therapy derived from Evidence-Based Korean Pharmacological Treatment Guideline for Depression, Revised Edition. METHODS: The guideline was developed through adaptation of 12 domestic and foreign clinical guidelines for depression, with key questions concerning pharmacotherapy of depression, and drawing of recommendations. RESULTS: The guideline strongly recommended dose increment, switching, and combination and augmentation therapy of antidepressant when patients with depression showed inadequate treatment outcomes from initial antidepressant treatment. The dose increment was strongly recommended when the patients had insufficient response from treatment with tricyclic antidepressants (TCAs), monoamine oxidase inhibitors, selective serotonin reuptake inhibitors (SSRIs), and serotonin and norepinephrine reuptake inhibitors (SNRIs). Switching from SSRI to non-SSRI was also strongly recommended. The combination of initial medication and other classes of antidepressants could benefit from treatment with TCAs, SSRIs, SNRIs, and noradrenergic and specific serotonergic antidepressants. Combination with norepinephrine and dopamine reuptake inhibitors or serotonin-2 antagonist/reuptake inhibitors was weakly recommended. The guideline strongly recommended use of the augmentation strategy of adding lithium or benzodiazepine to initial antidepressants. Augmentation of lamotrigine, T3, methylphenidate, and modafinil was weakly recommended. CONCLUSION: If the initial outcomes of antidepressant therapy are unsatisfactory to the patients the next-step strategies of dose increment, switching, combination and augmentation of antidepressants should be considered after rechecking the patients' drug compliance, dose, and diagnosis.

No Association between Serotonin Receptor 2C-759C/T Polymorphism and Weight Change or Treatment Response to Mirtazapine in Korean Depressive Patients

OBJECTIVE: Activation of one or more serotonin (5-HT) receptors may play a role in mediating the antidepressant effects of serotonergic antidepressants. The serotonin 2C (5HT 2C) receptor is known to be associated with antidepressant action and weight gain. We sought to determine whether the 5-HTR 2C receptor -759C/T polymorphism was associated with weight gain and treatment response to mirtazapine in major depressive disorder (MDD) patients. METHODS: The 5-HT 2C receptor -759C/T polymorphism was analyzed in 323 MDD patients. All patients were evaluated using the 21-item Hamilton Depression Rating Scale at the beginning of the study and at 1, 2, 4, and 8 weeks of mirtazapine treatment. RESULTS: There was no significant difference in the 5-HT 2C receptor -759C/T genotype distribution between responder and non-responder groups. The 5-HT 2C receptor -759C/T polymorphism was not associated with weight change over time after mirtazapine administration. CONCLUSION: The 5-HT 2C receptor -759C/T polymorphism does not appear to be a predictor of treatment response to mirtazapine. This polymorphism was not associated with weight change after 8 weeks of mirtazapine treatment. Further investigation on other polymorphisms of the 5-HT 2C gene is required to determine whether the 5-HT 2C gene influences treatment response and weight change after mirtazapine administration in patients with major depressive disorder.

Evidence-Based Korean Pharmacological Treatment Guideline for Depression, Revised Edition (I) : Initial Choice of Antidepressant Treatment / 신경정신의학

OBJECTIVES: The aim of this study is to establish Korean pharmacological treatment guidelines for the initial choice of antidepressant for treatment of moderate or severe depression. METHODS: The process for establishment of guidelines involved determination of important key questions, selection of 12 international and domestic clinical practice guidelines for depression, drawing of recommendation drafts, and peer review. RESULTS: Selective serotonin reuptake inhibitors (SSRIs), serotonin-norepinephrine reuptake inhibitors (SNRIs), norepinephrine-dopamine reuptake inhibitors (NDRI), and noradrenergic and specific serotonergic antidepressants (NaSSA) were strongly recommended as the first-line antidepressants for treatment of moderate or severe depression. SSRIs were weakly recommended for patients who had problems with tolerability. Consideration of not only efficacy but also provisional adverse effects, drug-drug interactions, history of treatment response, preference, acceptability, cost, comorbid illnesses, and other factors in the choice of first-line antidepressants was strongly recommended. The treatment recommendations for specific clinical features of depression were as follows. SSRIs were weakly recommended for atypical depression. Augmented use of antipsychotics to antidepressants was strongly recommended for psychotic depression. Bupropion and SSRIs were weakly recommended for seasonal depression. CONCLUSION: The results of this study may contribute toward improving the quality of depression treatment by providing clear and definite recommendations for the initial choice of antidepressant for treatment of moderate or severe depression.