title: Addiction resistance: Definition, validation and association with mastery.
abstract: BACKGROUND
  For given levels of psychoactive substance use, symptoms of substance use disorder (SUD) can vary widely. The concept of addiction resistance (AR) seeks to capture this variation so we can understand its causes.
  
  
  METHODS
  In a population-based twin sample, AR was defined as the deviation in the number of reported SUD criteria for a given substance from that predicted from the level of maximal consumption. Therefore, subjects with strong AR demonstrate few symptoms of SUD even at high levels of consumption. Twin modeling was performed by Mx.
  
  
  RESULTS
  We assessed AR for alcohol, nicotine and cannabis. Heritability was assessed at two occasions thereby correcting for measurement error and ranged from 35 to 52% with no evidence for shared environment. ARs for alcohol, nicotine and cannabis were relatively stable over time and were substantially predicted by parental history of SUD, early adversity, comorbidity with both internalizing and externalizing disorders, personality and especially by the trait of mastery.
  
  
  CONCLUSIONS
  AR, which assesses individual variation in sensitivity to the development of SUD for a given level of drug exposure, may be a useful concept for addiction research. As applied to common psychoactive substances, AR is moderately heritable, relatively stable and predicted by family history, comorbidity and personality. The relationship with mastery is of particular interest in that it may reflect an ability to resist the progression of the addictive process into key life domains and to avoid loss of control of intake, even when consuming at high levels.
authors.affiliation: Virginia Institute for Psychiatric and Behavioral Genetics, Virginia Commonwealth University School of Medicine, Richmond, VA, USA; Department of Psychiatry, Virginia Commonwealth University School of Medicine, Richmond, VA, USA; Department of Human and Molecular Genetics, Virginia Commonwealth University School of Medicine, Richmond, VA, USA. Electronic address: kendler@vcu.edu.
authors.forename: Kenneth S
authors.initials: KS
authors.lastname: Kendler
authors.affiliation: Virginia Institute for Psychiatric and Behavioral Genetics, Virginia Commonwealth University School of Medicine, Richmond, VA, USA; Department of Psychiatry, Virginia Commonwealth University School of Medicine, Richmond, VA, USA.
authors.forename: John
authors.initials: J
authors.lastname: Myers
mesh_terms: D016739:Behavior, Addictive / Q000523:psychology*; D002188:Cannabis / Q000009:adverse effects*; D015897:Comorbidity; D000431:Ethanol / Q000009:adverse effects; D005192:Family Health; D005260:Female; D006801:Humans; D008297:Male; D001523:Mental Disorders / Q000150:complications; D008960:Models, Psychological; D009538:Nicotine / Q000009:adverse effects*; D010551:Personality; D010554:Personality Disorders / Q000453:epidemiology; D019655:Quantitative Trait, Heritable; D012649:Self Concept; D019966:Substance-Related Disorders / Q000150:complications / Q000175:diagnosis* / Q000453:epidemiology / Q000235:genetics / Q000523:psychology*; D014427:Twins / Q000523:psychology*
chemical_list: D000431:Ethanol; D009538:Nicotine
keywords: Addiction; Alcohol; Cannabis; Mastery; Nicotine; Resistance