隨意使用大麻和酒精會降低重度憂鬱青少年的治療效果
作者：Caroline Cassels
出處：WebMD醫學新聞
【24drs.com】October 30, 2009 (檀香山) — 不經意的使用一些物質會顯著降低重度憂鬱異常(major depressive disorder，MDD)且有治療阻抗性之青少年的抗憂鬱治療效果，這項研究發現建議醫師們必須篩檢此一高風險族群的物質濫用，一旦發現有此現象，就必須進一步介入。
來自匹茲堡大學的研究者在美國兒童與青少年精神科學院第56屆年會發表這篇新研究，顯示常有低於最低限度的物質使用，在12週治療之後，低物質分數與較佳的治療反應有關，與研究對象在開始時的物質濫用相關缺損高低無關。
研究者、Benjamin I. Goldstein醫師向Medscape Psychiatry表示，更重要的是，研究結束時還有多少物質濫用的小孩。那些一開始就沒有濫用物質者以及後來停止使用者，有比較好的抗憂鬱治療反應。但是，那些繼續濫用物質者或在研究期間開始濫用物質者，其治療反應顯著降低。
這些發現來自「Treatment of Resistant Depression in Adolescents (TORDIA)」研究的次研究，檢視於選擇性血清素再吸收抑制劑venlafaxine的治療中，新增認知行為治療是否會改善原本治療失敗之MDD青少年的治療結果。
【矛盾的醫師】
MDD青少年的物質濫用異常與自殺行為、不佳治療結果、法律方面的困難、有風險的性行為、功能不佳等有關。不過，研究者指出，少有人知道降低物質濫用的程度對於那些未達物質濫用或未成癮之青少年治療反應的影響。
Goldstein醫師表示，醫師關於消遣性濫用大麻或酒精的矛盾看法促成了這個次研究。
Goldstein醫師表示，某種程度上，實驗之於青少年的發展是適合的，醫師通常不願意介入。但是，治療阻抗性MDD青少年的實驗性物質濫用風險，和一般青少年使用大麻或酒精的風險不同。
該研究包括了334名MDD青少年，以藥物使用與嚴重度指數(Drug Use and Severity Index)評估與治療和憂鬱症狀有關的物質使用。
研究者發現，28.1%的研究對象指出在開始時曾反覆嘗試性的使用酒精或大麻。物質濫用相關缺陷與開始時的憂鬱嚴重度、年紀較長、肢體/性暴力、家庭衝突、無望、併有對立性反抗疾患/ 品行疾患等有關。
該研究也顯示，開始時的自殺意念可預測物質濫用相關缺陷增加，父母親的憂鬱症狀可預測持續較高的物質濫用相關缺陷。
【臨床上值得注意】
Goldstein醫師表示，此研究認為，不管某人是否符合物質濫用或成癮規範，都必須注意這些病患的物質濫用情況。身為醫師，我們必須微調有關物質濫用的方法，且瞭解即使是嘗試性或不經意的物質濫用，在臨床上都值得注意，也必須直接向青少年提出。
雖然還不清楚其中的潛在機轉，以及不經意的物質濫用對於抗憂鬱治療會有直接影響。但Goldstein醫師推測，物質濫用的青少年比較不會有動機去恢復。
Goldstein醫師表示，需要後續研究來檢視這類病患偶爾物質濫用與縱向結果之間的關聯。研究者也正在進行此一世代的24週資料分析。
美國兒童與青少年精神科學院第56屆年會：摘要1.41。發表於2009年10月26日。
Casual Cannabis, Alcohol Use Reduces Treatment Efficacy in Adolescents With Major Depression
By Caroline Cassels
Medscape Medical News
October 30, 2009 (Honolulu, Hawaii) — Casual substance can significantly reduce the efficacy of antidepressant therapy in adolescents with treatment-resistant major depressive disorder (MDD) — a finding that suggests clinicians need to screen for — and intervene when they detect — any substance use in this at-risk population.
New research presented here at the American Academy of Child and Adolescent Psychiatry 56th Annual Meeting by investigators from the University of Pittsburgh, Pennsylvania, shows that subthreshold substance use is common and that low substance scores after 12 weeks of therapy were associated with better treatment response regardless of whether participants had high or low baseline substance-related impairment.
"It was more important how much substance use kids were involved in at the end of the study than at study outset. So those who started off using and ended up not using had...[an] antidepressant response [that] was as good as anyone else's. But those who continued to use substances or who progressed to substance use during the study had a significantly lower treatment response," study investigator Benjamin I. Goldstein, MD, told Medscape Psychiatry.
These current findings are a substudy of the larger Treatment of Resistant Depression in Adolescents (TORDIA) study, which is examining whether adding cognitive therapy to treatment with the selective serotonin reuptake inhibitor venlafaxine improved outcomes in adolescents with MDD who had failed previous treatment.
Physician Ambivalence
Substance use disorders among adolescents with MDD have been associated with suicidality, poor treatment outcomes, legal difficulties, risky sexual behavior, and functional impairment. However, the researchers note that little is known about the effect of lower levels of substance use and treatment response in adolescents who do not meet criteria for substance abuse or dependence.
Dr. Goldstein said the substudy was also prompted by the ambivalence clinicians have with regard to recreational substance abuse with cannabis or alcohol.
"To a certain extent, it is developmentally appropriate for adolescents to experiment, and clinicians are often reluctant to intervene. But the risks of experimental substance use in adolescents with treatment-resistant MDD are not the same as the risks of cannabis or alcohol use for adolescents in general," said Dr. Goldstein.
The study included 334 adolescents with MDD who were assessed for substance use with the Drug Use and Severity Index in relation to treatment and depressive symptoms.
The investigators found that 28.1% of the participants reported repeated substance use experimentation with alcohol or cannabis at baseline. Substance-related impairment was associated with baseline depression severity, older age, physical/sexual abuse, family conflict, hopelessness, and comorbid oppositional defiant disorder/conduct disorder.
The study also showed that baseline suicidal ideation predicted increased substance-related impairment, and parental depressive symptoms predicted persistence of high substance-related impairment.
Clinically Noteworthy
"This study suggests that regardless of whether someone meets the criteria for substance abuse or dependence, substance use should be an area of clinical focus in these patients. As clinicians, we have to be more fine-tuned in our approach to substance use and understand that even recreational or social substance use is something that is clinically noteworthy and worth addressing directly with adolescents," said Dr. Goldstein.
Although the underlying mechanisms are not clear, it is possible that casual substance abuse has a direct effect on antidepressant therapy. Dr. Goldstein also speculated that youth involved in substance use may be less motivated to recover.
Dr. Goldstein said further research is needed to examine the association of occasional substance use and longitudinal outcomes in this patient population. The researchers are also conducting analyses on 24-week data in this cohort.
American Academy of Child Adolescent Psychiatry 56th Annual Meeting: Abstract 1.41. Presented October 26, 2009.
