CHRONIC FATIGUE - RISK-FACTORS FOR SYMPTOM PERSISTENCE IN A 2-1 2-YEAR FOLLOW-UP-STUDY/

BACKGROUND: The prolonged disability of patients suffering from chroni c fatigue may be due to sustaining factors that are independent of the cause and subject to intervention. This study reexamined a cohort of patients with chronic fatigue to define medical and psychiatric predic tors of persistent symptoms. METHODS: Seventy-eight patients with chro nic fatigue present for 6 months or more (not required to meet the Cen ters for Disease Control case definition for chronic fatigue syndrome [CFS]) completed a self-report, follow-up questionnaire to measure the overall improvement or worsening of their condition at a mean of 2.5 years after their initial examination. At the time of initial evaluati on, patients underwent a structured psychiatric examination, physical examination, laboratory studies, and self-report measures of psycholog ical distress and functional disability. The psychiatric examination q ueried the patient about 28 somatic symptoms that are separate from th ose associated with CFS. Discriminant analysis was used to determine w hich variables present at the initial examination were significant pre dictors of persistent symptoms and disability at 2.5 years. RESULTS: T he factors most important at the time of initial presentation in predi cting persistent illness were: (1) more than eight medically unexplain ed physical symptoms separate from those associated with CFS case defi nition; (2) lifetime history of dysthymia; (3) duration of chronic fat igue symptoms greater than 1.5 years; (4) less than 16 years of formal education; and (5) age older than 38 years. None of the results of th e initial physical examination, or immunologic, general laboratory, or viral antibody measurements were significant in predicting persistenc e of symptoms. Recovery rates for those who met the criteria for CFS b y rate of noncases, but the differences were not statistically signifi cant. The five aforementioned variables formed a significant discrimin ative function, correctly classifying 78% of those who recovered and 7 4% of those with persistent symptoms. CONCLUSIONS: At initial examinat ion, patients with chronic fatigue, more than eight medically unexplai ned physical symptoms (excluding symptoms in the case criteria for CFS ), a lifetime history of dysthymic disorder, longer than 1.5 years of chronic fatigue, less than 16 years of formal education, and who were older than 38 years were the most likely to have persistence of sympto ms of chronic fatigue at the 2.5-year follow-up.