In our Forum discussion "journal club" series, the editors of Schizophrenia Bulletin provide access to the full text of a recent article. A short introduction by a journal editor gets us started, and then it's up to our readers to share their ideas and insights, questions, and reactions to the selected paper. So read on".
An introduction by Gunvant Thaker gets us started, and then it's up to our readers to share their ideas and insights, questions and reactions to these papers.
Send in your comments now! The paper under discussion:
Harvey PD, McClure MM, Patterson TL, McGrath JA, E Pulver A, Bowie CR, Siever LJ. Impairment in Functional Capacity as an Endophenotype Candidate in Severe Mental Illness. Schizophr Bull . 2011 May 11. Abstract
Background Text By Gunvant Thaker, Professor and Chief, Schizophrenia Related Disorders Program, Maryland Psychiatric Research Center and Deputy Editor, Schizophrenia Bulletin
The majority of individuals with severe mental illnesses, such as schizophrenia and bipolar disorder, experience impairments in everyday functioning in real-world settings. These impairments occur early in the course of the illness and persist even after successful treatment of overt symptoms. Functional impairments are some of the main reasons for the high individual and societal burden associated with severe mental illnesses. In a recent paper published online in Schizophrenia Bulletin, Phil Harvey and colleagues argue that genetics may contribute to these impairments, although there are complex other determinants of real-world functional impairments, including environmental factors that need to be parsed out. One way of achieving this is to focus on measures of functional capacity that have robust psychometric properties and arguably are less influenced by environmental factors. The paper identifies a need for further examination of functional capacity measures as endophenotypes establishing their familial characteristics and heritability estimates.
Considering the burden associated with functional impairments, ideas presented by the paper are interesting and provide new directions. At the same time, it raises many questions for discussion: Do measures of functional disability represent much more complex phenotypes than clinical diagnosis, making them ill-suited for genetic studies? Successful gene hunting for complex phenotypes is likely dependent on identifying simple endophenotypes that are more proximal to genetic effects. Considering this, is the focus on measures of functional capacity misguided? Or, is such a focus likely to identify processes underlying the functional capacity measures and thus better suited for genetic studies as Harvey and colleagues propose?