The effects of the Dark Triad personality traits on health protective behaviours: dyadic approach on self-reports and partner-reports

Abstract

Objective

The growing evidence show that romantic partners’ personality traits mutually influence each other’s health. The research on relationship between personality and health behaviours should include both partner’s perspectives - relations between individuals’ traits and their own outcomes (actor effects), and relations between individuals’ traits and their partners’ outcomes (partner effects). The objective of this study was to examine the actor and partner effects of the Dark Triad (DT) personality traits (psychopathy, Machiavellianism and narcissism) on the health protective behaviours (HPB) in romantic couples.

Design

A convenience sample of 188 heterosexual romantic couples participated in a cross-sectional round-robin study. Three predictor measures were Self-Report Psychopathy Scale-III, Narcissistic Personality Inventory and MACH-IV inventory, whereas HPB inventory was used as criterion variable.

Results

Data were analysed using the Actor-Partner Interdependence Model (APIM). The results suggest that men’s psychopathy, and to a lesser extent men’s Machiavellianism exert deleterious effects on their own and their partner’s HPB. The majority of these effects replicated across both self-reports and partner-reports. Women’s DT traits exerted weaker actor and partner effects on the HPB than men’s DT traits.

Conclusions

Findings show that men’s psychopathy and Machiavellianism have detrimental effects on their own as well as their partner’s HPB.

Keywords:

• Dark Triad personality traits
• actor-partner interdependence model
• romantic relationships
• health protective behaviours

Acknowledgement

We would like to thank two anonymous reviewers for their helpful comments.

Disclosure statement

No potential conflict of interest was reported by the authors.

Data availability

The data that support the findings of this study are available from the corresponding author, Jasna Hudek-Knezevic, upon reasonable request.

Additional information

Funding

This work has been fully supported by the University of Rijeka under the project number uniri-drustv-18-231.