To describe the Lundby Study and present recent data for the period 1947-1997.

The Lundby population consisting of 3563 probands was investigated by semi-structured interviews in 1947, 1957, 1972 and 1997. Sufficient information was available for 94-99%. Best estimate consensus diagnoses have been used since 1957 together with DSM-IV and ICD-10 in 1997.

From 1947-1972 to 1972-1997 a decrease in almost all age- and sex-specific incidences of neurotic and organic disorders was observed, whereas psychotic disorders increased consistently in males, but decreased in most age intervals in females. Women had higher first incidence depression rates than men and the average annual rate was lower for women and tended to be lower for men 1972-1997 as compared with 1947-1972. Median age at first onset of depression was around 35 years for individuals followed up for 30-49 years. The recurrence rate was about 40% and varied from 17% to 76% depending on length of follow-up. Transition to diagnoses other than depression was registered in 21% of the total sample, alcohol disorders in 7% and bipolar disorders in 2%.

The overall long-term suicide risk varied from 5,6% to 6.8%. The long term suicide risk was 3.1% for medium and 13.7% for severe MDD. Severity and male sex were risk factors. After the introduction of TCAs a fall in suicide rates among depressed individuals was observed. Certain clusters of personality traits may predict functional psychosis.

Low attrition rates over 50 years and reasonable diagnostic uniformity make comparisons over time justifiable.