RESUMO
The symptom of poor concentration and the ability to process information were measured prospectively in 245 subjects three times in the 6 months after glandular fever or an ordinary upper respiratory tract infection. The effects of the different infections, having a fatigue state, a psychiatric disorder, sleep disturbance, and estimates of premorbid intelligence were also assessed. The most frequent complaint of poor concentration and the worst information processing occurred at the onset of the infection, but these problems decreased over time, and were not related to each other. Multiple regression modeling showed that higher socioeconomic class and vocabulary IQ were associated with information processing ability at all three interviews. In contrast, logistic regression modeling showed that the symptom of poor concentration was associated with the severity of general psychiatric morbidity (CIS score) followed by suffering from a fatigue state. These results suggest that the ability to process information after these particular infections is related to estimates of premorbid IQ, whereas poor concentration is related independently to both psychiatric morbidity and a fatigue state, but not the particular infection itself.