To examine risk and protective processes for posttraumatic stress reactions and negative sequelae following the Northridge earthquake (EQ) among youths diagnosed for pre-EQ psychopathology.

Symptoms of posttraumatic stress disorder (PTSD), depression, general anxiety, and social Impairment were evaluated using telephone interviews among 66 children participating in a family-genetic study of childhood-onset depression at the time of the EQ.

Significant predictors of PTSD symptoms 1 year after the EQ included perceived stress and resource loss associated with the EQ, a pre-EQ anxiety disorder, and more frequent use of cognitive and avoidance coping strategies. PTSD symptoms were associated with high rates of concurrent general anxiety symptoms, depressive symptoms, and social adjustment problems with friends. The only significant correlation between sibling scores was on measures of sibling reports of objective exposure.

Preexisting anxiety disorders represent a risk factor for postdisaster PTSD reactions. Postdlsaster services need to attend to the needs of these youths as well as those of youths experiencing high levels of subjective stress, resource loss, and/or high exposure. That children within families show significant variation in postdisaster reactions underscores the need for attention to individual child characteristics and unshared environmental attributes. J. Am. Acad. Child Adolesc. Psychiatry, 1999, 38(8):1016–1023.