Abstract P405: Low Social Support Mediates the Effect of Marital Stress on 12-month Cardiac-Specific Quality of Life in Young Adults With Acute Myocardial Infarction

Background: Marital stress is associated with worse cardiac outcomes in young adults (≤55 years) with acute myocardial infarction (AMI), but whether psychosocial factors mediate this association remains largely unknown. We conducted a mediation analysis to investigate whether marital stress worsened quality of life (QoL) after AMI by increasing the likelihood of depression or low social support. Methods: There were 1,037 married/partnered AMI survivors aged 18-55 years enrolled in the VIRGO (Variation in Recovery: Role of Gender on Outcomes of Young AMI Patients) study (2008-2012) (67% women, mean age 47 years). Marital stress was measured by the Stockholm Marital Stress Scale at 1 month post-AMI; categorized as absent/moderate or severe. Depression (Patient Health Questionnaire-9 score ≥10), low social support (ENRICHD Social Support Instrument score ≤3 on ≥2 items and total score ≤18), and cardiac-specific QoL (Seattle Angina Questionnaire) were assessed at 1 year post-AMI. Natural direct and indirect effects of marital stress, depression, and low social support on QoL were estimated by causal mediation analysis with bias-corrected bootstrapped confidence intervals. Baseline QoL, sex, age, race, and socioeconomic factors (education, income, employment, and insurance status) were entered as covariates in all models. Results: There was a statistically significant direct effect from severe marital stress to lower 1-year cardiac-specific QoL after adjusting for covariates ( Figure ). Low social support and depression mediated 14.7% and 11.1% of the total relationship between marital stress and QoL, respectively; however, only the mediating effect through low social support was statistically significant. Conclusion: Marital stress was significantly associated with worse 1-year cardiac-specific QoL, and this effect was partially mediated by low social support. Interventions to decrease marital stress that also screen and provide resources for social support may help to improve AMI outcomes.