Persistently high psychological well-being predicts better HDL cholesterol and triglyceride levels: findings from the midlife in the U.S. (MIDUS) longitudinal study

BACKGROUND: Psychological correlates of blood lipid levels have been previously evaluated mostly in cross sectional studies. However, prospectively measured psychological factors might also predict favorable blood lipid profiles, thereby indicating a healthy mind/body interplay that is associated with less disease, better health and longer lives. METHODS: This paper examined whether longitudinal profiles of psychological well-being over 9-10 years are predictors of blood lipid profiles. Using the MIDUS (Midlife in the U.S.) biological subsample (n = 1054, aged 34 to 84, 55% female), cross-time trajectories of well-being were linked with three lipid outcomes (i.e., HDL cholesterol, triglycerides, and LDL cholesterol), measured for the first time at the 2nd wave of the study. RESULTS: Most adults showed largely stable profiles of well-being, albeit at different levels. Some showed persistently high well-being over time, while others revealed persistently low or moderate well-being. After adjusting for the effect of demographics, health behaviors, medications, and insulin resistance, adults with persistently high levels of environmental mastery and self-acceptance-two components of psychological well-being-had significantly higher levels of HDL as well as significantly lower levels of triglycerides compared to adults with persistently low levels of well-being. Converging with prior findings, no association was found between well-being and LDL cholesterol. CONCLUSIONS: Over 9-10 years, persistently high levels of psychological well-being measures predicted high HDL cholesterol and low triglycerides. These findings add longitudinal evidence to the growing body of research showing that positive psychological factors are linked with better lipoprotein profiles. A better blood lipid profile, particularly higher HDL-C, may be key in mediating how psychological well-being positively impacts health and length of life. Additional research is required to further validate this hypothesis as well as to establish potential underlying mechanisms.