Personality and outcome in depression: an 18-month prospective follow-up study

Background: The relationship between personality and depressive illness is complex. The aim of this study was to assess whether the presence of a personality disorder or high neuroticism (N) scores predicted longer times to discharge or remission onset or higher risks of relapse for a cohort of depressed subjects admitted for the first time. Methods: 100 consecutive subjects with ICD-10-defined depression were recruited on admission and followed up prospectively over an 18-month period. Personality function was rated using the informant-rated Standard Assessment of Personality in addition to the self-rated Maudsley Personality Inventory. Remission onset and relapse were defined operationally by scores on the Hamilton Rating Scale using recommended criteria. Results: The presence of a personality disorder predicted longer times to remission onset. Personality trait accentuation did not. Higher end N-scores correlated with longer times to remission onset. Neither personality disorder nor high N-scores predicted relapse or discharge risk. Subjects with a personality disorder were treated as aggressively as those without but those with higher N-scores were not. Limitations: It is an in-patient sample. Fifteen subjects dropped out of follow-up and those who did so were more likely to have met criteria for two or more personality disorder categories or four or more traits from one personality disorder category. The analysis assumes that state and scar effects on N-scores were minimised. Treatment decisions were not controlled. Conclusions: These findings support the view that the presence of a personality disorder and high N-scores modify the short-term course to remission onset in depression.