Personality, Stress and the Partner: Prospective and Dyadic Predictors of Couple Dissolution in Two US Cohorts

Background. Personality and stress are known to go together with relationship problems. It is less clear whether they predict the end of a relationship years ahead, and whether a partner's traits matter on top of a person's own. These questions are central to the 2WO model (2-partner Weighted Odds), a planned model of couple risk developed by the author, which is intended to combine personality, neurodivergence, stress and reactions during conflict. Methods. Analyses in two US cohorts, each planned and written down before the data for that outcome were analysed. In Add Health (N = 4,923 at Wave IV, ages 24–32), neuroticism, trait anger and perceived stress were related to relationship quality and partner violence, resting pulse and blood pressure were related to partner violence, and the traits, stress and partner violence were related to marital dissolution and partner tension (a partner who criticizes or makes too many demands) about ten years later (Wave V). In the Health and Retirement Study (HRS), chronic stress in 2006 was related to spouse tension and dissolution through 2022 (N = 4,461 to 4,753). In 4,457 HRS couples, where husband and wife each answered their own questionnaire, we tested two things: whether a person's own anger, hostility, neuroticism and stress were related to the tension that person felt in the marriage (the "actor" effect), and whether the partner's traits were related to it as well (the "partner" effect). We also tested whether both spouses' traits predicted later separation or divorce. Results. Per SD, neuroticism, trait anger and perceived stress in Add Health predicted dissolution a decade later by +4.5, +2.9 and +6.1 percentage points (base rate 23%), and any partner violence at Wave IV predicted it by +15.1 points. Estimates were unchanged after weighting for selective attrition. Resting pulse and blood pressure were unrelated to partner violence. In HRS, chronic stress predicted dissolution over 16 years (+0.9 points per SD; base rate 4.1%). In couples, a partner's outwardly expressed anger (anger-out) went with as much tension in a person's marriage as that person's own anger did (+0.20 vs +0.18 SD), and partner neuroticism (+0.15), hostility (+0.08) and stress (+0.07) also contributed. Husbands' and wives' anger-out and hostility jointly predicted separation (Holm p = .038 and .002), with significant estimates Analysis code and aggregate output: https://doi.org/10.17605/OSF.IO/4X7RF