“Be Good to Others and Treat People as you Would Like to be Treated Yourself.” A Mixed Methods Investigation of Positive Social Relationships and Cardiovascular Health in the MIDUS Study

OBJECTIVE: We analyzed qualitative data about social relationships and examined their quantitative associations with concurrent and prospective cardiovascular health (CVH). METHODS: Cross-sectional analyses involved the Midlife in the United States (MIDUS) Study wave 2 (M2) and Refresher (MR) biomarker samples (N=2036). Longitudinal analyses involved participants with both M2 and MIDUS wave 3 (M3) biological data (N=650). Participants wrote responses to the question "What do you do to make your life go well?" Judges evaluated each response for 11 aspects of relationships (e.g., communication, mentoring). CVH was assessed at M2, MR, and M3 via the American Heart Association's Life's Essential 8 measure (i.e., a composite of diet, physical activity, smoking, sleep, blood pressure, cholesterol, glucose, BMI). Pre-registered linear regression models examined associations between each positive relationship aspect and CVH. RESULTS: Positive relationships were mentioned in 71.8% of responses. Aspects of relationships that were associated with CVH in unadjusted cross-sectional or longitudinal models included positively evaluating a relationship (i.e., loving, caring, respecting), spending time together, and physical intimacy. None of the relationship subthemes were associated with concurrent or prospective CVH after adjusting for sociodemographic factors and response word count. CONCLUSIONS: Qualitative assessments captured unique perspectives on social relationships that are relevant for well-being and are not well-represented with self-report measures. Although relational subthemes did not show significant associations with CVH, the null findings may reflect limited statistical power rather than the absence of meaningful effects. Promises and challenges of mixed methods biopsychosocial science and medicine research are discussed.