S. A. Mednick

The schizophrenia high‐risk project in Copenhagen: three decades of progress

We describe the design, theoretical approach and major recent findings of a prospective longitudinal study of the offspring of schizophrenic mothers and controls, initiated in 1962 by Sarnoff Mednick and Fini Schulsinger in Copenhagen, Denmark. Over 90% of the original 207 high‐risk and 104 low‐risk subjects have been successfully followed up since the initial assessment. At the time of the most recent assessment (1989), the subjects averaged 42 years of age and were nearly completely through the risk period for developing schizophrenia. By relating the lifetime psychiatric diagnoses of the subjects back to information on their premorbid experiences and functioning, we have identified several precursors of schizophrenia. This paper reviews our recent findings concerning whether outcomes of schizophrenia that differ in the relative prominence of negative versus positive symptoms represent discrete longitudinal syndromes. Predominantly negative and predominantly positive symptom schizophrenia were found to follow different patterns of symptom development from adolescence through the adult course of illness and were predicted by different combinations of genetic and environmental influences. Taken together, the findings suggest that the pathological processes underlying these two forms of schizophrenia are 1) partly independent of each other, 2) at least partly active during the premorbid state and 3) to some degree stable in the adult course of illness.

MMPI variables predictive of schizophrenia in the Copenhagen High-Risk Project: a 25-year follow-up

Moldin et al. (1) have identified a cluster of Minnesota Multiphasic Personality Inventory (MMPI) scales that discriminate adolescents at risk for schizophrenia from those not at risk. The present study examines how well Moldins scales predict schizophrenic decompensation in a sample of 207 Danish adolescents at high genetic risk for schizophrenia. Subjects were assessed using a modified, 304‐item MMPI in 1962 (mean age=15.1 years) and diagnosed in 10‐year and 25‐year follow‐ups. Premorbidly. schizophrenic subjects (n = 31) scorcd higher than subjects with no mental illness on the frequency (F) and psychoticism (PSY) scales. When paranoid and non‐paranoid preschizophrenics were separated, three scales (F, Pz (paranoid schizophrenia) and PSY) significantly discriminated paranoid preschizophrenics. Discriminant function analyses confirmed these results. It is concluded that the MMPI may be useful for identifying schizophrenia premorbidly.

Height, weight and body mass index in early adulthood and risk of schizophrenia

Objective:  To illuminate the possible associations between height, weight, and body mass index (BMI) during early adulthood and the development of schizophrenia.

A 30‐year follow‐up study of the sons of alcoholic men

The nature‐nurture question in the etiology of alcoholism is discussed. The research results from twin and adoption studies indicate a considerable genetic (= biological) component in the etiology of alcoholism. A longitudinal high‐risk study of alcoholism is presented. The sons of alcoholic men and matched controls have been followed prospectively since before birth. The main results from previous phases of the study and a recent 30‐year follow‐up assessment are presented.

Breastfeeding and risk of schizophrenia in the Copenhagen Perinatal Cohort

Objective:  The aim was to study whether early weaning from breastfeeding may be associated with increased risk of schizophrenia.

Hyperactive behavior and minor physical anomalies

ABSTRACT– Minor physical anomalies (MPAs) are congenital abnormalities of body structure which reflect fetal maldevelopment. They originate in the same embryonic layer that produces the central nervous system, and it is reasoned that MPAs are markers of nervous system anomalies. High MPA counts have been associated with hyperactive behavior in normal and clinical populations of boys, and with inhibited behavior in normal groups of girls. The present sample of children from a longitudinal study of a Danish birth cohort show no significant sex differences in mean number of MPAs, but the male hyperactivity‐MPA relation and the female inhibition‐MPA relation is supported in this non‐clinical sample. MPAs are not recommended for use in clinical screening or diagnosis at this time, but the evidence of a congenital, biological component to hyperactive behavior may eventually have useful implications for prevention and/or intervention.

Temporal course of symptoms and social functioning in relapsing schizophrenics: A 6-year follow-up

As a part of the Copenhagen High Risk project, a 6 year follow-up of relapses after first hospitalisation of 67 schizophrenic women was performed. Four dimensions of psychopathology were examined: positive symptoms, negative symptoms, formal thought disorder and depressive symptoms. Each symptom group was its own best predictor over time. Only depressive symptoms diminished significantly at a relapse 6 years after first hospitalisation. Broadly defined subtyping of schizophrenia into paranoid and non-paranoid, retained stability over a 6 year period. It is concluded that there is a stability of psychopathology across onset episodes and relapses.

Class drift and schizophrenia

ABSTRACT– This study is part of an ongoing analysis of 207 children with schizophrenic mothers (high‐risk subjects) and 104 low‐risk controls begun in 1962 by Mednick & Schulsinger. The purpose of this study was to examine class mobility in schizophrenics, using a prospective paradigm. In the present study, 14 high‐risk schizophrenics were matched with 14 high‐risk non‐schizophrenics and 14 low‐risk non‐schizophrenics on age, sex and social class origin. Groups were compared on highest class attainment and socio‐economic status in 1972. Results indicated that while high‐risk non‐schizophrenics were comparable in class attainment to low‐risk non‐schizophrenics, the high‐risk schizophrenics were downwardly mobile in comparison to their non‐schizophrenic high‐risk counterparts. The class drift hypothesis was thus supported.

Paternal alcoholism predicts the occurrence but not the remission of alcoholic drinking : a 40-year follow-up

Objective:  To test the effects of fathers alcoholism on the development and remission from alcoholic drinking by age 40.

Early Predictors of Onset and Course of Schizophrenia and Schizophrenia Spectrum

The purpose of this article is to provide an overview of early predictors of the onset and course of schizophrenia, with special emphasis on the results from the temporally most advanced prospective study of children of schizophrenic mothers, launched in Copenhagen in 1962 by Mednick and Schulsinger (1965), the so-called Copenhagen High Risk Project. The focus will be on predictors of onset rather than those related to course.