Generalized trust and all-cause mortality: A population-based prospective cohort study.

Aims: Social science literature suggests that unlimited trust in others may lead to adverse outcomes, and that moderate trust may be more optimal in social interactions. The aim was to analyze associations between generalized trust in other people and all-cause mortality using a four-alternative generalized trust item that includes moderate trust.

Study design: Prospective cohort study.

Methods: The 2008 Public Health Survey in Scania, southern Sweden, was conducted with a postal questionnaire followed by three reminders, with 28,198 respondents (54.1% response rate). The survey was linked to all-cause mortality register data with 9.3-year follow-up. Multiple Cox regression analyses were performed.

Results: The item "Most people can be trusted" yielded 5.5% "Completely agree," 57.6% "Agree," 29.5% "Don't agree" and 7.4% "Don't agree at all." Covariates of age, sex, socioeconomic status, chronic disease, mental health, health-related behaviors, social participation and social support showed significant bivariate associations with all-cause mortality. All-cause mortality remained significantly lower in the moderately high trust category ("Agree") compared to the very high trust reference category ("Completely agree") in the multiple analyses. In contrast, all-cause mortality in the low and very low trust categories did not significantly differ from the very high trust reference. Trust was also dichotomized into high trust ("Completely agree"/"Agree") versus low trust. Dichotomized low trust showed significantly higher all-cause mortality only when sex and age were included as covariates in the model.

Conclusions: The construction, use and interpretation of generalized trust items should be scrutinized, and moderate generalized trust in others investigated as a health protective factor.