title: Startle response to unpredictable threat in comorbid panic disorder and alcohol dependence.
abstract: BACKGROUND
  Although the adverse consequences of comorbid panic disorder (PD) and alcohol dependence (AD) are well-established, relatively little is known about the mechanisms underlying their co-occurrence. Several researchers have postulated that alcohol's ability to dampen response to unpredictable threat may be an important motivational factor in comorbid PD and AD. To date, no research has examined these processes using a clinical sample and it is unclear whether individuals with PD and AD evidence different reactivity to unpredictable threat relative to individuals with PD-only.
  
  
  METHODS
  The aim of the current study was to examine differences in aversive responding during predictable and unpredictable threat-of-shock in three groups of individuals with: (1) current PD and remitted AD (PD and AD), (2) current PD but no lifetime diagnosis of AD (PD-only), and (3) no lifetime diagnoses of PD or AD (controls). Aversive responding was assessed using a well-established electromyography (EMG) startle paradigm.
  
  
  RESULTS
  Results indicated that PD and AD individuals evidenced greater startle potentiation during unpredictable (but not predictable) threat relative to controls and PD-only individuals (who did not differ).
  
  
  CONCLUSIONS
  These findings suggest that heightened reactivity to unpredictable threat may be an important process in PD and AD comorbidity and a possible key motivational factor underlying engagement in alcohol use.
authors: University of Illinois - Chicago, Department of Psychology (M/C 285), 1007 West Harrison Street, Chicago, IL 60657, United States.
authors: Stephanie M
authors: SM
authors: Gorka
authors: Brady D
authors: BD
authors: Nelson
authors: Stewart A
authors: SA
authors: Shankman
mesh_terms: D000328:Adult; D000437:Alcoholism / Q000150:complications / Q000523:psychology*; D001007:Anxiety / Q000523:psychology; D003865:Major Depressive Disorder / Q000150:complications / Q000523:psychology; D039721:Diagnostic and Statistical Manual of Mental Disorders; D019263:Dysthymic Disorder / Q000150:complications / Q000523:psychology; D004576:Electromyography; D004644:Emotions / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D009483:Neuropsychological Tests; D016584:Panic Disorder / Q000150:complications / Q000523:psychology*; D011569:Psychiatric Status Rating Scales; D013216:Reflex, Startle / Q000502:physiology*; D012959:Socioeconomic Factors; D019966:Substance-Related Disorders / Q000150:complications / Q000523:psychology; D055815:Young Adult
keywords: Alcohol dependence; Anxiety; Comorbidity; Panic disorder; Startle response; Unpredictable threat