What would Sherlock Holmes have deduced from this book? The medical writer, Richard Asher, once likened understanding of the physical basis of mental illness to one of the Great Detective's astute remarks. In the episode in question Holmes responded to a request to solve a mysterious case from scraps of paper alone with the comment that the clues opened up a ‘pleasing field for intelligent speculation’.

The concept of lifetime comorbidity extends the familiar concept relating co-existing disorders to temporal discontinuity between two or more disorders in the same individual. This collection of essays examines the contribution of life-course epidemiology as an investigative tool in the search for clues to the aetiology of medical and psychiatric disorders. There is a selection bias towards contributors based in North America and the usual defects of conference-based publications are present, although largely ameliorated by consistent editing and rapid publication.

The strength of this book resides in its readable accounts of the concepts underpinning complex lines of research, examples being investigation of links between foetal experience and the pathogenesis of schizophrenia, and between depression and bone loss and osteoporosis. Risk factors, emotions and health, and others aspects of mood disorders and schizophrenia are also covered. As might be expected, the contributions introduce many ‘new’ concepts - allostasis, translational and reverse translational research, postmodern illness, and the fundamental social causes hypothesis, to cite a few. I found the discussion of putative autoimmune and metabolic mediation of physical comorbidities of schizophrenia of particular interest.

I suspect that both Holmes and Richard Asher would have enjoyed reading this book. Compared with Asher's essay of 1954, itself state of the art, there is clear evidence here of recent progress, from speculation to conceptualisation and beyond, in the understanding of medical aspects of the aetiology of major psychiatric disorders and, conversely, the role of psychiatric disorder in the causation of medical illness. In Holmesian terms this is a ‘three pipe’ book to be mulled over at leisure, in contemplation of new investigative ideas, rather than to be dipped into. It will thus probably appeal most to the research minded who I suspect would be best advised to recommend purchase to their library committee.