Psychosocial factors and public health: a suitable case for treatment?

Adverse psychosocial exposure or "misery" is associated with physical disease. This association may not be causal. Rather it may reflect issues of reverse causation, reporting bias, and confounding by aspects of the material environment typically associated with misery. A non-causal relation will not form the basis of effective public health interventions. This may be why psychosocial interventions have, so far, showed little effect on objective physical health outcomes. This paper reviews evidence for the "psychosocial hypothesis" and suggests strategies for clarifying these issues. It concludes that, although misery is clearly a bad thing as it erodes people's quality of life, there is little evidence that psychosocial factors cause physical disease. In the absence of better evidence, suggestions that psychosocial interventions are needed to improve population physical health, in both absolute and relative terms, seem premature.