成瘾

成瘾英語:)是指一種重複性的強迫行為,即使這些行為已知可能造成不良後果的情形下,仍然被持續重複[5]。這種行為可能因中樞神經系統功能失調造成,重複這些行為也可以反過來造成神經功能受損[6]可用于描述生理依賴或者过度的心理依赖,例如物質依賴药物滥用(即俗称的滥药瘾)、酒瘾瘾、性癮。或是持續出現特定行為(赌、暴食),网瘾赌瘾瘾、财迷、工作狂暴食症跟蹤狂偷窃狂整形迷恋、购物狂、發表廢文甚至恋物癖等,是生理或者心理上,甚至是同時具备的一种依赖症。

成瘾
Addiction
Brain positron emission tomography images that compare brain metabolism in a healthy individual and a cocaine addict
类型行為, 健康問題[*], 习惯
分类和外部资源
醫學專科成癮精神病學
成癮醫學
ICD-10F10-F19 subdivision .2
「成癮及生理、心理依賴」的相關術語詞彙表[1][2][3][4]
  • 成瘾腦部失調的情形,特徵是會強迫性的接觸犒赏刺激,不去考慮其帶來的負面結果。
  • 成瘾行为:具有犒赏性及正向增強效應的行為
  • 成瘾药物:具有犒赏性及正向增強效應的藥物
  • 依赖性:之前曾頻繁接觸刺激源(例如藥物攝取),中斷接觸後出現戒斷症狀的情形
  • 药物敏化逆耐药性:在固定藥物劑量的情形下重複給藥,而相同劑量的藥物效果增強的情形
  • 藥物戒斷:在重複藥物使用後停藥,出現的症狀
  • 生理依赖:出現持續生理戒斷症狀(例如疲勞及震顫性譫妄)的依赖性
  • 心理依赖:出現情緒或是精神戒斷症狀(例如煩躁失乐)的依赖性
  • 增强刺激:特定類型的刺激,接觸後會增加再接觸此刺激的可能性
  • 犒赏刺激:特定類型的刺激,大腦會認為此刺激是正向的,會想再進行的
  • 敏化作用:重複接受某一刺激後產生的刺激增強性反應
  • 物質使用疾患 :使用特定物質,而且造成臨床上或是功能上的損傷或是困境的情形
  • 藥物耐受性:重複接受某一藥物後產生的藥物降低性反應

瘾有分為物質成癮及行為成癮,行為成癮是和物质无关的强迫症,如赌瘾和网瘾。在这几种通常的用法中,瘾是描述一种某人高频率反复从事可能对其身心健康和社交生活有害的活动的一种强迫行为。而精神疾病診斷與統計手冊的第五版DSM-5中有將赌瘾(gambling disorder)列入[7]。有時成瘾(addiction)會和物質依賴(substance dependence)混淆[8]。兩者主要的不同是:物質依賴者在中斷物質使用後,會出現戒斷症狀,甚至造成更多的使用該物質,而成瘾是強制性的攝取某種物質或從事特定行為,不一定有戒斷症狀。

物質成瘾會對個人和社會帶來顯著的影響,包括成癮物質帶來的直接影響、伴隨的醫療費用、長期的併發症(例如吸煙可能造成的肺癌、酒癮可能會有的肝硬化、靜脈注射甲基苯丙胺會出現的冰毒嘴症狀)、神经可塑性(因為經驗原因引起大腦結構的改變)帶來的影響、以及後續生產力的下降[9][10][11]。成瘾的典型現象包括對於物質或是行為的無法控制及過度關注,雖然有不良結果,卻仍然繼續攝取成瘾物質或從事特定行為的情形[12]。伴隨著成癮的習慣或是行為模式通常是立即性的滿足(短期回報)及延遲出現的不良影響(長期不良結果)[13]

有时在口语上,瘾也用于指某些人的一些癖好,例如读书、收集(集邮)、看电视、玩游戏、购物、工作、上网、运动及进食等。不過在本条目中,瘾主要是被用于滥用药物和物质滥用问题,也就是有生理依賴或者过度心理依赖的行為。

醫學觀點

医学上,成癮是腦中犒賞系統在基因转录表觀遺傳機制上出現的失調,成癮有許多心理上的原因,但依生理來說,是在長期暴露在高度的成癮刺激原(addictive stimulus,例如嗎啡、可卡因、性交、賭博等)後出現的情形[2][14][15]。重複暴露在成癮刺激原是主要導致成癮以及維持成癮現象的主要病理因素[2][16]。成癮刺激原有二個特性,一個是其正向增強(接觸後會增加再去進行類似行為的可能性),另一個是內在犒賞(認為此物質或是行為有趣、會想要再去進行)[2][3][17]

转录因子ΔFosB是各種成癮(行為成癮或物質成癮)發展中的關鍵成份及共同因素[14][15][18][19]。二十多年針對ΔFosB在成瘾當中的研究,結果指出成瘾的出現以及伴隨的强迫行为加剧或减弱,都和伏隔核中D1型中度多刺神經元中ΔFosB的基因過度表現(genetic overexpression)有關[2][14][15][18]。因為ΔFosB基因表現與成瘾之間有因果關係,ΔFosB在臨床前研究中常作為成瘾的生物標記[2][14][18]。ΔFosB在這些神經元的表現會一方面會直接調高藥物Self-administration及犒賞敏感度,也會透過正增強達到這些效果,另一方面也會降低對厭惡(aversion)的敏感度[note 1][2][14]

腹側被蓋區被認為與神經生物學理論中的成癮現象有關。[20][21]

藥物成癮

診斷藥物成癮可診斷為生理成癮、成癮有增加或減退跡象、和沒有成癮。DSM-IV中介紹的包括:

流行病學

因為文化的不同,特定時間內出現藥物成癮或是行為成癮的比例(即患病率)會隨時代及國家而不同,也會因為年齡層、社會經濟地位等人口学資料而不同[22]。澳洲2009年的藥物濫用患病率為5.1%[23]。依照美國2011年在青少年中抽樣的結果來看,其酒癮及非法藥物濫用的lifetime prevalence(個體從出生後,一直到接受抽樣之前,曾出現過的比例)分別是8%及2-3%[10]

参见

腳註

  1. 降低對厭惡的敏感度,簡單來說,就是讓個人的行為比較不會被其不想要的負面結果而影,比較不因為有可能負面結果而不去做該行為

參考資料

  1. Malenka RC, Nestler EJ, Hyman SE. . Sydor A, Brown RY (编). 2nd. New York: McGraw-Hill Medical. 2009: 364–375. ISBN 9780071481274.
  2. Nestler EJ. . Dialogues Clin. Neurosci. December 2013, 15 (4): 431–443. PMC 3898681. PMID 24459410.
  3. . Mount Sinai School of Medicine. Department of Neuroscience. [9 February 2015].
  4. Volkow ND, Koob GF, McLellan AT. . N. Engl. J. Med. January 2016, 374 (4): 363–371. PMID 26816013. doi:10.1056/NEJMra1511480.
  5. Angres DH, Bettinardi-Angres K. . Dis Mon. October 2008, 54 (10): 696–721. PMID 18790142. doi:10.1016/j.disamonth.2008.07.002.
  6. American Society for Addiction Medicine. . 2012.
  7. Clinical and Research Implications of Gambling Disorder in DSM-5
  8. American Psychiatric Association. (PDF). American Psychiatric Publishing: 1–2. 2013 [10 July 2015]. Additionally, the diagnosis of dependence caused much confusion. Most people link dependence with "addiction" when in fact dependence can be a normal body response to a substance.
  9. Malenka RC, Nestler EJ, Hyman SE. . Sydor A, Brown RY (编). 2nd. New York: McGraw-Hill Medical. 2009: 4. ISBN 9780071481274. Drug abuse and addiction exact an astoundingly high financial and human toll on society through direct adverse effects, such as lung cancer and hepatic cirrhosis, and indirect adverse effects—for example, accidents and AIDS—on health and productivity.
  10. KR Merikangas KR, McClair VL. . Hum. Genet. June 2012, 131 (6): 779–789. PMC 4408274. PMID 22543841. doi:10.1007/s00439-012-1168-0.
  11. (PDF). American Board of Addiction Medicine. 14 March 2016 [3 April 2016].
  12. Morse RM, Flavin DK. . JAMA. August 1992, 268 (8): 1012–4. PMID 1501306. doi:10.1001/jama.1992.03490080086030.
  13. Marlatt GA, Baer JS, Donovan DM, Kivlahan DR. . Annu Rev Psychol. 1988, 39: 223–52. PMID 3278676. doi:10.1146/annurev.ps.39.020188.001255.
  14. Ruffle JK. . Am. J. Drug Alcohol Abuse. November 2014, 40 (6): 428–437. PMID 25083822. doi:10.3109/00952990.2014.933840.
    The strong correlation between chronic drug exposure and ΔFosB provides novel opportunities for targeted therapies in addiction (118), and suggests methods to analyze their efficacy (119). Over the past two decades, research has progressed from identifying ΔFosB induction to investigating its subsequent action (38). It is likely that ΔFosB research will now progress into a new era – the use of ΔFosB as a biomarker. ...
    Conclusions
    ΔFosB is an essential transcription factor implicated in the molecular and behavioral pathways of addiction following repeated drug exposure. The formation of ΔFosB in multiple brain regions, and the molecular pathway leading to the formation of AP-1 complexes is well understood. The establishment of a functional purpose for ΔFosB has allowed further determination as to some of the key aspects of its molecular cascades, involving effectors such as GluR2 (87,88), Cdk5 (93) and NFkB (100). Moreover, many of these molecular changes identified are now directly linked to the structural, physiological and behavioral changes observed following chronic drug exposure (60,95,97,102). New frontiers of research investigating the molecular roles of ΔFosB have been opened by epigenetic studies, and recent advances have illustrated the role of ΔFosB acting on DNA and histones, truly as a ‘‘molecular switch’’ (34). As a consequence of our improved understanding of ΔFosB in addiction, it is possible to evaluate the addictive potential of current medications (119), as well as use it as a biomarker for assessing the efficacy of therapeutic interventions (121,122,124). Some of these proposed interventions have limitations (125) or are in their infancy (75). However, it is hoped that some of these preliminary findings may lead to innovative treatments, which are much needed in addiction.
  15. Olsen CM. . Neuropharmacology. December 2011, 61 (7): 1109–1122. PMC 3139704. PMID 21459101. doi:10.1016/j.neuropharm.2011.03.010. Functional neuroimaging studies in humans have shown that gambling (Breiter et al, 2001), shopping (Knutson et al, 2007), orgasm (Komisaruk et al, 2004), playing video games (Koepp et al, 1998; Hoeft et al, 2008) and the sight of appetizing food (Wang et al, 2004a) activate many of the same brain regions (i.e., the mesocorticolimbic system and extended amygdala) as drugs of abuse (Volkow et al, 2004). ... Cross-sensitization is also bidirectional, as a history of amphetamine administration facilitates sexual behavior and enhances the associated increase in NAc DA ... As described for food reward, sexual experience can also lead to activation of plasticity-related signaling cascades. The transcription factor delta FosB is increased in the NAc, PFC, dorsal striatum, and VTA following repeated sexual behavior (Wallace et al., 2008; Pitchers et al., 2010b). This natural increase in delta FosB or viral overexpression of delta FosB within the NAc modulates sexual performance, and NAc blockade of delta FosB attenuates this behavior (Hedges et al, 2009; Pitchers et al., 2010b). Further, viral overexpression of delta FosB enhances the conditioned place preference for an environment paired with sexual experience (Hedges et al., 2009). ... In some people, there is a transition from "normal" to compulsive engagement in natural rewards (such as food or sex), a condition that some have termed behavioral or non-drug addictions (Holden, 2001; Grant et al., 2006a). ... In humans, the role of dopamine signaling in incentive-sensitization processes has recently been highlighted by the observation of a dopamine dysregulation syndrome in some patients taking dopaminergic drugs. This syndrome is characterized by a medication-induced increase in (or compulsive) engagement in non-drug rewards such as gambling, shopping, or sex (Evans et al, 2006; Aiken, 2007; Lader, 2008)."
    Table 1: Summary of plasticity observed following exposure to drug or natural reinforcers"
  16. American Society for Addiction Medicine. . 2012.
  17. Taylor SB, Lewis CR, Olive MF. . Subst. Abuse Rehabil. February 2013, 4: 29–43. PMC 3931688. PMID 24648786. doi:10.2147/SAR.S39684. Initial drug use can be attributed to the ability of the drug to act as a reward (ie, a pleasurable emotional state or positive reinforcer), which can lead to repeated drug use and dependence.8,9 A great deal of research has focused on the molecular and neuroanatomical mechanisms of the initial rewarding or reinforcing effect of drugs of abuse. ... At present, no pharmacological therapy has been approved by the FDA to treat psychostimulant addiction. Many drugs have been tested, but none have shown conclusive efficacy with tolerable side effects in humans.172 ...A new emphasis on larger-scale biomarker, genetic, and epigenetic research focused on the molecular targets of mental disorders has been recently advocated.212 In addition, the integration of cognitive and behavioral modification of circuit-wide neuroplasticity (ie, computer-based training to enhance executive function) may prove to be an effective adjunct-treatment approach for addiction, particularly when combined with cognitive enhancers.198,213–216 Furthermore, in order to be effective, all pharmacological or biologically based treatments for addiction need to be integrated into other established forms of addiction rehabilitation, such as cognitive behavioral therapy, individual and group psychotherapy, behavior-modification strategies, twelve-step programs, and residential treatment facilities.
  18. Biliński P, Wojtyła A, Kapka-Skrzypczak L, Chwedorowicz R, Cyranka M, Studziński T. . Ann. Agric. Environ. Med. 2012, 19 (3): 491–496. PMID 23020045. For these reasons, ΔFosB is considered a primary and causative transcription factor in creating new neural connections in the reward centre, prefrontal cortex, and other regions of the limbic system. This is reflected in the increased, stable and long-lasting level of sensitivity to cocaine and other drugs, and tendency to relapse even after long periods of abstinence. These newly constructed networks function very efficiently via new pathways as soon as drugs of abuse are further taken ... In this way, the induction of CDK5 gene expression occurs together with suppression of the G9A gene coding for dimethyltransferase acting on the histone H3. A feedback mechanism can be observed in the regulation of these 2 crucial factors that determine the adaptive epigenetic response to cocaine. This depends on ΔFosB inhibiting G9a gene expression, i.e. H3K9me2 synthesis which in turn inhibits transcription factors for ΔFosB. For this reason, the observed hyper-expression of G9a, which ensures high levels of the dimethylated form of histone H3, eliminates the neuronal structural and plasticity effects caused by cocaine by means of this feedback which blocks ΔFosB transcription
  19. Robison AJ, Nestler EJ. . Nat. Rev. Neurosci. November 2011, 12 (11): 623–637. PMC 3272277. PMID 21989194. doi:10.1038/nrn3111. ΔFosB has been linked directly to several addiction-related behaviors ... Importantly, genetic or viral overexpression of ΔJunD, a dominant negative mutant of JunD which antagonizes ΔFosB- and other AP-1-mediated transcriptional activity, in the NAc or OFC blocks these key effects of drug exposure14,22–24. This indicates that ΔFosB is both necessary and sufficient for many of the changes wrought in the brain by chronic drug exposure. ΔFosB is also induced in D1-type NAc MSNs by chronic consumption of several natural rewards, including sucrose, high fat food, sex, wheel running, where it promotes that consumption14,26–30. This implicates ΔFosB in the regulation of natural rewards under normal conditions and perhaps during pathological addictive-like states.
  20. . 博客來: 187. [2018-12-23].
  21. . 9900 新聞頻道 - 9900 台灣網站導航. [2018-12-23].
  22. Vassoler FM, Sadri-Vakili G. . Neuroscience. 2014, 264: 198–206. PMC 3872494. PMID 23920159. doi:10.1016/j.neuroscience.2013.07.064. The environment also plays a large role in the development of addiction as evidenced by great societal variability in drug use patterns between countries and across time (UNODC, 2012). Therefore, both genetics and the environment contribute to an individual's vulnerability to become addicted following an initial exposure to drugs of abuse.
  23. Slade, T.; Johnston, A.; Teesson, M.; Whiteford, H.; Burgess, P.; Pirkis, J.; Saw, S. (PDF). Department of Health and Ageing, Canberra. May 2009.

外部連結

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