OBJECTIVE: To examine period trends in the rate of suicide in the first 28 days after discharge from psychiatric hospital.

DESIGN: Cohort study of patients discharged from psychiatric hospital. Setting: Scotland. Subjects: All patients aged 15-84 who were discharged from Scottish psychiatric hospitals during 1968 to 1992. Outcome measure: The rate of suicide (classified as codes E950-9 and E980-9 according to the International Classification of Diseases, Ninth Revision) within 28 days of discharge per 100000 person years at risk for five year periods during 1968 to 1992. Crude, within cohort rates and externally standardised rates were calculated.

RESULTS: Overall, 196 male patients committed suicide in 20520 person years at risk, and 171 female patients committed suicide in 24114 person years at risk. A significant linear trend was seen in period effect on externally standardised mortality ratios in both sexes: a decrease in male patients (P=0.008) and an increase in female patients (P=0.0001). The adjusted standardised mortality ratio in 1988-92 compared with 1968-72 was 0.62 (95% confidence interval 0.39 to 0.98) in male patients and 2.73 (1.64 to 4.56) in female patients.

CONCLUSION: The increase in the rate of suicide in the 28 days after discharge in female psychiatric patients makes this an increasingly important period to target. The rise has occurred against the background of a reduction of 60% in the number of psychiatric beds for adults. Key messages Key messages In Scotland during 1968 to 1992 the standardised rate of suicide in the first 28 days after discharge almost trebled in female patients and decreased by 40% in male patients These period trends have occurred against a background of important changes in mental health service provision, with a 60% reduction in the number of psychiatric beds for adults between 1976 and 1992 and a trend towards shorter stays The increase in the suicide rate soon after discharge in female patients highlights the increasing importance of targeting services at recently discharged patients