Hippocampal volume, PTSD, and alcoholism in combat veterans.
Studies imposing rigorous control over lifetime alcohol intake have usually not found smaller hippocampal volumes in persons with posttraumatic stress disorder. Because the majority of negative studies have used adolescent samples, it has been suggested that chronicity is a necessary condition for such findings. To test the hypothesis that a smaller hippocampus in PTSD is unrelated to comorbid alcoholism or to chronicity, this study estimated hippocampal volume in a relatively large group (N=99) of combat veterans in which PTSD, lifetime alcohol abuse/dependence, and Vietnam versus Gulf War service were crossed. In subjects with histories of alcoholism, unadjusted hippocampal volume was 9% smaller in persons with PTSD than in those without PTSD. In nonalcoholic subjects, the PTSD-related difference in hippocampal volume was 3%. The failure to observe a strong association between PTSD and hippocampal volume in nonalcoholic subjects was not ascribable to younger age, reduced PTSD chronicity, or lower PTSD symptom severity. The possibility that smaller hippocampal volume is limited to groups in which PTSD is compounded by comorbid alcoholism is not necessarily incompatible with results suggesting a smaller hippocampus is predispositional to PTSD. Further examination of the role of alcoholism and other comorbid conditions in studies of brain structure and function in PTSD appears warranted.
National Center for PTSD, Clinical Laboratory and Education Division, Mail Code 334 PTSD, VA Palo Alto HCS, 3801 Miranda Ave., Palo Alto, CA 94304, USA. steve.woodward@med.va.gov
Steven H
SH
Woodward
Danny G
DG
Kaloupek
Chris C
CC
Streeter
Matthew O
MO
Kimble
Allan L
AL
Reiss
Stephan
S
Eliez
Lawrence L
LL
Wald
Perry F
PF
Renshaw
Blaise B
BB
Frederick
Barton
B
Lane
Javaid I
JI
Sheikh
Wendy K
WK
Stegman
Catherine J
CJ
Kutter
Lorraine P
LP
Stewart
Rebecca S
RS
Prestel
Ned J
NJ
Arsenault
D000328:Adult; D000367:Age Factors; D000437:Alcoholism / Q000175:diagnosis* / Q000453:epidemiology / Q000473:pathology; D001284:Atrophy / Q000473:pathology; D003130:Combat Disorders / Q000175:diagnosis* / Q000453:epidemiology / Q000473:pathology; D015897:Comorbidity; D003865:Major Depressive Disorder / Q000175:diagnosis / Q000453:epidemiology; D017831:Diagnosis, Dual (Psychiatry); D004198:Disease Susceptibility / Q000175:diagnosis; D005260:Female; D047830:Gulf War; D006624:Hippocampus / Q000473:pathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011569:Psychiatric Status Rating Scales; D013313:Stress Disorders, Post-Traumatic / Q000175:diagnosis* / Q000453:epidemiology / Q000473:pathology; D014728:Veterans / Q000523:psychology / Q000706:statistics & numerical data*; D047829:Vietnam Conflict; D014888:Wechsler Scales