PURPOSE: This study presents psychiatric correlates in Chronic Fatigue Syndrome (CFS) that emerged from the CDC's Surveillance Study. It seeks to determine the time of onset and rates of syndromal psychiatric disorders and identify the predominant disorder. Other goals are to ascertain whether depression is associated with CFS symptomatology, compare syndromal to self- reported depression, and test for the specificity of the 1988 CDC case definition for CFS.METHODS: All 565 enrolled subjects had fatiguing illnesses and were evaluated for CFS. They completed the Diagnostic Interview Schedule for the DSM-III-R and the Beck Depression Inventory. Prevalence estimates for current syndromal psychiatric disorders were calculated. CFS symptoms were compared by depression status. Syndromal and self-reported depression were contrasted. Groups that did and did not meet the case definition were compared by three outcome variables.RESULTS: Rates of current psychiatric disorders were high in CDC subjects compared to the community. The predominant disorder was depression. Although prior disorders tended to persist (75%), many disorders were incident to the fatiguing illness (57%). Depression was not associated with increased CFS symptomatology. There was only weak agreement between measures of syndromal and self-reported depression (kappa = 0.3219). Subjects designated as CFS had similar rates of syndromal psychiatric disorders, syndromal depression, and self-reported depression as did non-CFS subjects.CONCLUSIONS: Current syndrome; psychiatric disorders appear associated with fatiguing illnesses. While prior psychiatric disorders are risk factors for current, the onset was largely concurrent with the fatiguing illnesses. The BDI should probably not be used as a measure for psychiatric morbidity in CFS subjects. Regardless of outcome, there was no evidence of specificity of psychiatric features to the CDC case definition.