Background: Social environment plays a central role in substance use behaviors. However, it is not clear whether its role varies as a function of individual dispositional characteristics.
Objectives: To investigate the interaction between dispositional characteristics (i.e. sensation seeking, anxiety/neuroticism) and social environment (i.e. perceived social support [PSS]) in association with substance use.
Methods: A representative sample of 5,377 young Swiss males completed a questionnaire assessing substance use, sensation seeking, anxiety/neuroticism, and PSS from friends and from a significant other.
Results: Sensation seeking and anxiety/neuroticism were positively related to most substance use outcomes. PSS from friends was significantly and positively related to most alcohol and cannabis use outcomes, and significantly and negatively associated with the use of hard drugs. PSS from a significant other was significantly and negatively associated with most alcohol and cannabis use outcomes. The associations of sensation seeking with drinking volume, alcohol use disorder and the use of illicit drugs other than cannabis were stronger in individuals reporting high levels of PSS from friends than those with low levels. The associations of sensation seeking with risky single-occasion drinking and the use of hard drugs were weaker in participants reporting high levels of PSS from a significant other than in those with low levels.
Conclusions: Sensation seeking and anxiety/neuroticism may constitute risk factors for substance use and misuse. PSS from friends may amplify the risk for alcohol and illicit drug use (other than cannabis) associated with high sensation seeking, whereas the PSS from a significant other may reduce it.
Keywords: Risky single-occasion drinking; alcohol; cannabis; drugs; moderator; personality; social support; tobacco.