Remission onset and relapse in depression. An 18-month prospective study of course for 100 first admission patients

Few prospective studies of course for first admission depressives are reported.

One hundred consecutive depressed inpatients were followed prospectively over 18 months. Course was defined operationally using the Hamilton Depression scale and ICD-10 criteria. Results were analysed using life-tables.

The cumulative probabilities of remission onset by 3 and 18 months were 0.67 (95% C.I.=0.57-0.77) and 0.82 (95% C.I.=0.74-0.90). The cumulative probability of relapse was 0.25 (95% C.I.=0.15-0.35); 53% of those relapsing did so in the first 2 months. Younger age at onset, longer illness length, higher depression and anxiety ratings, predicted delayed remission onset. ICD-10 episode severity predicted relapse.

The chances of remission onset at 3 months and relapse were increased relative to other studies; risk of chronicity was similar. Predictors of outcome to emerge were similar to other studies.

Adoption of these remission onset criteria may identify earlier (at 3 months), subjects at high risk of chronicity. After remission onset, subjects with severe illnesses warrant careful follow-up to detect relapse, particularly during the first 2 months.

The operational criteria used were different to other prospective studies. Relatively few psychosocial variables were included in the analysis.