Differentiating adults who think about self-harm from those who engage in self-harm: the role of volitional alcohol factors

Background: Self-harm, an act of self-poisoning or self-injury irrespective of motivation, is a major public health concern. Use of alcohol prior to or alongside acts of self-harm is common but little is known about the alcohol-related mechanisms of self-harm enaction. We utilised an ideation-to-action approach to clarify the extent to which volitional alcohol factors differentiated those who have thoughts of self-harm but do not act on them (self-harm ideation) and those who engage in self-harm (self-harm enaction). Methods: Cross-sectional analyses of the baseline phase of the Health Lifestyle and Wellbeing study: 1546 adults (1079 female; Mean age = 34 y; 92% White) resident in Scotland completed measures of demographics, lifetime self-harm, volitional alcohol factors and psychosocial factors. Multinomial logistic regression compared those with a history of self-harm thoughts ('ideation', n = 297), self-harm acts ('enaction', n = 346) and 'controls' (n = 897) to identify volitional alcohol factors associated with self-harm enaction. Results: Volitional alcohol factors differentiated those with a history of self-harm enaction from those with a history of self-harm ideation (as well as those with no history) in initial models adjusted for demographics and depressive symptoms: the self-harm enaction group reported stronger alcohol-related negative urgency (OR = 1.74, 95% CI 1.41-2.16, p < .001), more frequent heavy drinking (OR = 1.46, 95% CI 1.24-1.72, p < .001) and stronger expectancies that drinking alcohol leads to negative self-perceptions (OR = 1.33, 95% CI 1.03-1.72, p = 0.03) and markers of self-harm risk (OR = 1.64, 95% CI 1.18-2.30, p = 0.004). Alcohol-related negative urgency and heavy-drinking frequency continued to differentiate those in the self-harm enaction group from those in ideation group in multivariate models. Consistent with theoretical models positing phase-specific moderators of self-harm ideation and enaction, psychosocial factors (perceived stress, support, negative mood regulation expectancies) differentiated those with a history of self-harm ideation from those without but not those in the ideation and enaction groups. Conclusions: Management of self-harm risk requires better understanding of alcohol-related mechanisms of self-harm enaction. Volitional alcohol factors may play a role in governing the translation of self-harm thoughts into self-harm acts.