Does missing trust lead to overuse or underuse of health care services?

Research about mistrust in health care often relies on the narrative that lacking trust causes underuse of health care services. This narrative seemed to hold up in the COVID-19 pandemic era, when mistrust in systems and providers led to widely recognized vaccine hesitancy and reluctance to seek care. In this review, we suggest that the "mistrust leads to underuse" narrative is important but incomplete, as mistrust in health care may also cause patients to overuse health care services. We searched the literature for studies, meta-analyses, and interviews that assessed the effect of patient trust on health care utilization. Although overuse literature is sparse, surveys and physician interviews indicate that patients who do not trust their clinicians may seek multiple opinions on the same diagnosis and utilize more costly interventions that are not recommended. Physicians also report being more likely to utilize extraneous tests and medications when patients do not trust them. Hence, problems of trust may lead to both underuse and overuse of health care services. We postulate several factors that may influence whether a mistrustful patient underuses or overuses health care resources, including personal characteristics, environmental characteristics, and levels of analysis, and we encourage more investigation about mistrust and health care overutilization.