How are you doing? The person-specificity of daily links between neuroticism and physical health

Objective: The mind and body function in tandem across days and development, and in unique ways for individuals, but most work on the relation between personality and physical health is cross-sectional, assuming homogeneity across time and people. For instance, although neuroticism is associated with poor health, the direction of the relation and whether it characterizes all people all of the time is unclear. The goal of this study is to fill knowledge gaps concerning the person-specific, day-to-day neuroticism-health link.

Methods: A 75-occassion intensive longitudinal study was conducted in which 119 adults reported daily on 12 indicators of neuroticism and 3 symptoms of physical health. Person-specific network analyses, conducted using the multiple solutions version of group iterative multiple model estimation (GIMME-MS), were used to determine the presence, valence, daily lag, and direction of relations among the daily variables. Network features were compared within and between individuals.

Results: Person-specific networks were heterogeneous. Participants were significantly more likely to have networks in which physical symptoms predicted indicators of neuroticism compared to the reverse; this was particularly true for next-day relations, and for women. Exploratory analyses suggested that participants with a disproportionate amount of these health-to-neuroticism relations scored high on conscientiousness.

Conclusions: Person-specific network mapping of ecologically-valid intensive longitudinal data revealed heterogeneity in day-to-day relations between indicators of neuroticism and physical health, with long-term implications for personalized healthcare. There was some consistency, however, in that "body" symptoms were more likely to predict "mind" features across people.