Effect of continuity of care on medical expenditures for hypertensive patients in high-altitude areas of China

Managing hypertension is particularly challenging in high-altitude regions of China due to chronic hypoxia and limited healthcare access. Continuity of care has been proposed as a cost-effective approach, yet its economic impact in this context remains unclear. Using basic medical insurance claims data from 11,823 hypertensive patients in three high-altitude cities (January 2022-December 2023), this study examined the association between continuity of care and medical expenditures. A generalized linear model with a log link function was employed to analyze total medical costs, while a Tobit regression model was used to assess out-of-pocket (OOP) costs. Heterogeneity was analyzed based on sex, insurance type, and ethnic groups. If the Bice-Boxerman Continuity of Care Index (COC) were maximized, hypertensive patients could experience a 15.63% reduction in total medical costs and 25.92% in OOP costs. If the Usual Provider of Care Index (UPC) were maximized, total medical costs and OOP costs could decrease by 18.94% and 31.61%, respectively. Heterogeneity analysis indicated that both COC and UPC were negatively associated with OOP costs across sex and insurance types, but significant associations with total medical costs were mainly observed among Tibetan patients, females, and those enrolled in Urban and Rural Resident Basic Medical Insurance. Higher continuity of care was significantly associated with lower medical expenditures for hypertensive patients residing in high-altitude areas; however, the magnitude of this beneficial effect varied considerably across different population subgroups. These heterogeneous effects suggest that interventions designed to enhance care continuity may need to be tailored to specific patient demographics. Therefore, future prospective studies or policy interventions are warranted to validate these findings.