Affective diseases–their course in a longitudinal perspective: the Lundby Study

Abstract

SummaryTo gain an impression of the course of affective diseases such as Anxiety and Depression in a longitudinal perspective, information was taken from the Lundby Study, Sweden. This is an epidemiological, longitudinal and prospective study of an entire population followed up over 25 years. The first prevalence study was undertaken by Essen-Möller et al. who in 1947 examined every person registered in a geographically delimited area, Lundby, in southern Sweden. They personally interviewed and described every single individual of the 2 550 inhabitants. They were as interested in healthy as in sick people. This is important, since many persons do not consult a psychiatrist, or even another doctor, for their suffering. In this way, the examining psychiatrists saw the whole panorama of mental disease. In 1957 Hagnell carried out a reinvestigation of the same people wherever they then lived, and in 1972 Hagnell and Öjesjö performed a third examination of all the probands of the 1947 cohort. On all three occasions the drop-out rate was negligible: a few percent only. Each time additional information was collected from various outside sources of relevance.Anxiety and Depression are common diseases. Within the Lundby Study single episodes as well as relapses into the same or another mental illness are described. During the 25-year period, the total number of registered spells of Anxiety was 215 (79 for men and 136 for women), while the number of spells of Depression was 516 (189 for men and 327 for women).The cumulative probability of contracting an affective illness at least once in a lifetime (lifetime risk) was for “Anxiety proper” in men 2.6 and in women 6.1 percent; for “Anxiety plus other psychiatric symptoms” in men 8.6 and in women 16.8 percent; for “Depression proper” in men 6.8 and in women 15.5 percent; for “Depression plus other psychiatric symptoms” in men 17.3 and in women 32.1 percent.We found that in “Anxiety proper” relapses, the subsequent episodes contain more complicated syndromes along with the anxiety state. “Anxiety plus other psychiatric symptoms” seems to be a diagnosis that includes many symptoms which, if relapses occur, may develop into various other syndromes.Many of those who have an initial episode of Depression proper remain within to this diagnosis if they relapse. “Depression plus other psychiatric symptoms”, on the other hand, mostly relapses into other mental diagnoses. It thus seems to be a prodromal syndrome to other mental illnesses.