Psychiatric Morbidity in Ketamine Users Attending Counselling and Youth Outreach Services

Background: No study has examined ketamine users’ psychiatric morbidity using structured diagnostic instruments. The aim of this study was thus to determine the psychiatric comorbidity of community-based ketamine users using the Structured Clinical Interview for DSM-IV (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition), Axis I Disorders (SCID). Methods: A convenience sample of 200 frequent ketamine users was recruited from community organizations in Hong Kong. Participants were screened with the Severity of Dependence Scale (SDS), Beck Depression Inventory (BDI), Anxiety subscale of the Hospital Anxiety Depression Scale (HADSA), and SCID psychotic symptoms. Those who scored above the threshold (cutoff point of 8/9 on the BDI and 4/5 on HADSA) or displayed evidence of psychotic symptoms were referred for a structured clinical interview conducted by a psychiatrist. Results: One hundred and seventy participants scored above the cutoff point on 1 or more of the scales, and 115 participants attended the SCID interview. Fifty-one of these 115 participants received a psychiatric diagnosis of 1 or more comorbidities for the month preceding the interview. Mood disorders accounted for 80.4% of the diagnoses, anxiety disorders for 33.3%, and psychotic disorders for 7.8%. Conclusions: Female gender and history of psychiatric/psychological clinic attendance were significantly associated with comorbid psychiatric disorders, whereas ketamine dependence had a borderline association.     

Role of BDNF in the pathophysiology and treatment of depression: Activity‐dependent effects distinguish rapid‐acting antidepressants

The pathophysiology and treatment of depression have been the focus of intense research and while there is much that remains unknown, modern neurobiological approaches are making progress. This work demonstrates that stress and depression are associated with atrophy of neurons and reduced synaptic connectivity in brain regions such as the hippocampus and prefrontal cortex that contribute to depressive behaviors, and conversely that antidepressant treatment can reverse these deficits. The role of neurotrophic factors, particularly brain‐derived neurotrophic factor (BDNF), has been of particular interest as these factors play a key role in activity‐dependent regulation of synaptic plasticity. Here, we review the literature demonstrating that exposure to stress and depression decreases BDNF expression in the hippocampus and PFC and conversely that antidepressant treatment can up‐regulate BDNF in the adult brain and reverse the effects of stress. We then focus on rapid‐acting antidepressants, particularly the NMDA receptor antagonist ketamine, which produces rapid synaptic and antidepressant behavioral actions that are dependent on activity‐dependent release of BDNF. This rapid release of BDNF differs from typical monoaminergic agents that require chronic administration to produce a slow induction of BDNF expression, consistent with the time lag for the therapeutic action of these agents. We review evidence that other classes of rapid‐acting agents also require BDNF release, demonstrating that this is a common, convergent downstream mechanism. Finally, we discuss evidence that the actions of ketamine are also dependent on another growth factor, vascular endothelial growth factor (VEGF) and its complex interplay with BDNF.     

瑞芬太尼和氯胺酮静脉麻醉用于重睑术的效果比较

目的：比较瑞芬太尼复合异丙酚和氯胺酮复合异丙酚在重睑成形手术中的静脉镇痛、镇静效果及清醒时间、手术时间和不良反应的发生率。方法：选择200例ASAⅠ-Ⅱ级择期行重睑成形术患者,随机分为A、B两组各100例。A组：瑞芬太尼复合异丙酚;B组：氯胺酮复合异丙酚。分别以瑞芬太尼复合异丙酚或氯胺酮复合异丙酚缓慢静脉推注,观察记录两组患者在入室麻醉前（t0）、静脉麻醉后即刻（t1）、局部浸润麻醉后即刻（t2）、局部浸润麻醉后5min（t3）、局部浸润麻醉后10min（t4）、局部浸润麻醉后20min（t5）时的心率（HR）、收缩压（SBP）、舒张压（DBP）变化情况及脉搏血氧饱和度（SpO2）,并记录两组患者的静脉麻醉镇痛与镇静效果、清醒时间、手术时间以及术中与术后恶心呕吐、呼吸抑制及躁动等不良反应。结果：A组患者静脉麻醉后（t1）与麻醉前（t0）相比HR、SBP、DBP有所下降,但差异无统计学意义（P＞0.05）;B组患者静脉麻醉后（t1）HR、SBP、DBP较麻醉前（t0）有所升高,差异有统计学意义（P＜0.05）;t1、t2、t3、t4节点B组HR、SBP、DBP均明显高于A组,两组差异有统计学意义（P＜0.05）;两组患者的静脉麻醉镇痛、镇静效果均很好,差异无统计学意义（P＞0.05）;A组与B组清醒时间分别为（6.5±2.2）min、（25.1±4.5）min,差异有统计学意义（P＜0.05）;A组与B组手术时间分别为（50.1±9.7）min、（83.4±11.5）min,差异有统计学意义（P＜0.05）;A组不良反应、并发症低于B组,差异有统计学意义（P＜0.05）。结论：瑞芬太尼与异丙酚静脉复合麻醉用于重睑成形术对患者的心血管刺激小,血流动力学影响小、并发症少;患者清醒时间、手术时间均较氯胺酮复合异丙酚麻醉时间短。总之,瑞芬太尼与异丙酚静脉复合麻醉用于重睑成形术效果优于氯胺酮复合异丙酚麻醉。     

Evidence‐based treatment strategies for treatment‐resistant bipolar depression: a systematic review

Sienaert P, Lambrichts L, Dols A, De Fruyt J.
Evidence‐based treatment strategies for treatment‐resistant bipolar depression: a systematic review.
Bipolar Disord 2012: 00: 000–000. © 2012 John Wiley & Sons A/S.Published by Blackwell Publishing Ltd. Objectives: Treatment resistance in bipolar depression is a common clinical problem that constitutes a major challenge for the treating clinician as there is a paucity of treatment options. The objective of this paper was to review the evidence for treatment options in treatment‐resistant bipolar depression, as found in randomized controlled trials and with special attention to the definition and assessment of treatment resistance. Methods: A Medline search (from database inception to May 2012) was performed using the search terms treatment resistance or treatment refractory, and bipolar depression or bipolar disorder, supplemented with 43 separate searches using the various pharmacologic agents or technical interventions as search terms. Results: Only seven studies met our inclusion criteria. These studies examined the effects of ketamine (n = 1), (ar)modafinil (n = 2), pramipexole (n = 1), lamotrigine (n = 1), inositol (n = 1), risperidone (n = 1), and electroconvulsive therapy (ECT) (n = 2). Conclusions: The available level I evidence for treatment strategies in resistant bipolar depression is extremely scarce, and although the response rates reported are reassuring, most of the strategies remain experimental. There is an urgent need for further study in homogeneous patient samples using a clear concept of treatment resistance.     

Propofol with N-Acetylcysteine Reduces Global Myocardial Ischemic Reperfusion Injury More than Ketamine in a Rat Model

Objective: We examined the cardioprotective effects of propofol and ketamine with and without N-acetylcysteine (NAC). Methods: 60 rats were divided into six groups of 10 rats each. Anesthesia induction was produced with an intraperitonal injection of ketamine in Groups 1–3 and propofol in Groups 4–6. NAC (200 mg kg^{? 1}) was given intraperitonally during anesthesia induction in Groups 3 and 6. Groups 2, 3, 5, and 6 were subjected to 90 s of myocardial ischemia by clamping the ascending aorta, and then reperfusion was begun by unclamping the ascending aorta. After 60 min of reperfusion, blood samples were taken from the ascending aorta for biochemical analyses, and heart tissue samples were taken for biochemical and histopathological analyses. Results: Creatine kinase (CK), myocardial band of creatine kinase (CK-MB), and troponin-I (Tn-I) levels were significantly higher in the ischemia–reperfusion groups (2, 3, 5, 6) compared to the nonischemic groups (1, 4). CK, CK-MB, and Tn-I levels did not differ significantly between the ketamine groups (1–3) and the propofol groups (4–6) p >. 05). Malondialdehyde levels were significantly higher in Groups 2 and 3 than in Group 1 and were significantly lower in Groups 4 and 6 than in Group 5 (p <. 05). Malondialdehyde levels in the propofol groups (4–6) were significantly lower than in the ketamine groups (1–3; p <. 05). Catalase levels in propofol groups were higher than ketamine groups. Superoxide dismutase levels were significantly higher in Group 6 than in Group 3 (p <. 05). Conclusions: In this rat model of global cardiac ischemia, propofol with NAC attenuates myocardial injury more than ketamine (with or without NAC).     

亚麻醉剂量氯胺酮对抑郁小鼠肠道菌群的影响

目的：　探究亚麻醉剂量氯胺酮对雄性和雌性抑郁样小鼠肠道菌群的影响。方法：　SPF级健康雄性和雌性C57BL/6小鼠各20只,随机分为8组（n=5）：雌性对照组（FC组）,雌性氯胺酮组（FCK组）,雌性抑郁组（FD组）和雌性抑郁+氯胺酮组（FDK组）;雄性对照组（MC组）,雄性氯胺酮组（MCK组）,雄性抑郁组（MD组）和雄性抑郁+氯胺酮组（MDK组）。FCK组和MCK组经尾静脉注射质量分数为10 mg/kg的氯胺酮,FC组和MC组经尾静脉注射等量生理盐水;FD组、FDK组、MD组和MDK组采用慢性不可预知温和应激（chronic unpredictable mild stress,CUMS）造模,造模后FDK组和MDK组分别经尾静脉注射10 mg/kg氯胺酮,FD组和MD组注射等量生理盐水。采用强迫游泳实验、糖水偏好实验和旷场试验评价小鼠抑郁行为变化,接着采集不同组别小鼠粪便进行粪便微生物16S rDNA序列定性分析及功能预测分析。采用单因素方差分析（one-way ANOVA）不考虑性别时各组肠道菌群的变化,采用双因素方差分析（two-way ANOVA）性别因素和氯胺酮处理对肠道菌群的影响,必要时进一步采用Tukey校正的多重比较对实验结果进行后检验。P<0.05为差异有统计学意义。结果：　分别与不同性别的对照组比较,使用CUMS方法处理小鼠后,强迫游泳不动时间明显延长（P<0.05）,糖水偏好度明显下降（P<0.05）,旷场试验水平运动得分和垂直运动得分明显减少（P<0.05）。经亚麻醉剂量氯胺酮处理后,行为学检测结果表明小鼠均有不同程度的改善（P<0.05）。物种组成分析结果显示,在经过CUMS造模处理后,各组小鼠肠道菌群多样性和丰度未发生明显改变。物种差异分析发现,亚麻醉剂量氯胺酮可以改善抑郁小鼠放线菌的降低程度,使肠道菌群的组成发生变化,并使雌性抑郁小鼠Bacteroidaceae相对丰度降低程度得到缓解,而雄性抑郁小鼠Alistipes相对丰度增加。结论：　不同性别小鼠对CUMS刺激和亚麻醉剂量氯胺酮处理表现出不同的肠道菌群变化。亚麻醉剂量氯胺酮可以改善抑郁小鼠放线菌的降低程度,并缓解雌性抑郁小鼠Bacteroidaceae相对丰度降低程度,增加雄性抑郁小鼠Alistipes相对丰度,进而改善小鼠的抑郁样行为。