Stress–Diathesis Model of Suicidal Behavior

Suicide and attempted suicide are complex behaviors, and a large number of proximal and distal risk factors have been identified (Hawton and van Heeringen, 2009). These risk factors can be categorized in explanatory models, which may help to understand suicidal individuals and facilitate the assessment of suicide risk. Early models have identified key determinants operating during the development of disorders or behavioral problems. For example, psychologists have developed schema models that focused on cognitive characteristics of, for example, depression, anxiety, and personality disorders. This conceptual approach and the empirical research motivated by such models have led to significant insights into these disorders (Ingram and Luxton, 2005). Stress has also been identified as a key determinant of psychopathology, so that a variety of models have featured stress as a primary determinant. Such models suggest that severe enough negative events can precipitate disorders even without reference to individual biological or psychological characteristics. The stress model of suicidal behavior is an example of such models. It is based on the observation that stressful life events are commonly recognized as triggers of suicidal behavior. A variety of explanatory models, including those applied by lay people, have indeed featured stress as a primary determinant of suicidal behavior. Such models indicate that negative life events if severe enough can precipitate suicidal behavior even without the existence of individual predisposing psychological or biological characteristics. Until recently, most studies of suicidal behavior were based on such early models and thus restricted to one domain of possible risk factors, for example, social, psychiatric, or psychological. As pointed out by Mann et al. (1999), such studies are too narrowly focused to estimate the relative importance of different types as risk factors or their interrelationship. A model of suicidal behavior has to take into account proximal and distal risk factors and their potential interaction (Hawton and van Heeringen, 2009). Stress models of suicidal behavior can indeed not explain the observations that even extreme stress does not lead to suicidal behaviors in all exposed individuals. Such observations have led to the recognition that the development of suicidal behavior involves a vulnerability or diathesis as a distal risk factor, which predisposes individuals to such behavior when stress is encountered. This chapter will review the scientific literature on the stress–diathesis model of suicidal behavior. Preceding this review, general issues regarding the origins, definitions, and components of stress–diathesis models will be addressed. The concluding discussion will point at the advantages of using stress–diathesis models for treating and preventing suicide risk and address issues with regard to future research.