Cost-consequence analysis of salvianolate injection for the treatment of coronary heart disease

Background: Complicated with the impact of aging population and urbanization, coronary heart disease (CHD) incurs more and more disease burdens in China. Salvianolate injection is a Chinese patent drug widely used for treating CHD in China. A series of studies have verified the efficacy of salvianolate injection, but the high drug cost has raised concerns. It is, therefore, important to conduct cost-consequence analysis to demonstrate whether salvianolate injection is associated with outcome improvement and cost containment. The aim of this study was to retrospectively evaluate the cost-consequence of salvianolate injection for the treatment of coronary heart disease by combining salvianolate injection with conventional treatment from a societal perspective. Methods: We retrospectively studied hospitalized patients with CHD from August 2011 to December 2015 by using electronic medical record database. Patients who received salvianolate injection combined with conventional treatment were selected as exposed group, while those who received conventional treatment alone were selected as unexposed group. Propensity score matching (PSM) analysis was used to balance the characteristics of patients. After PSM, we evaluated hospital stay, total nitrates dosage, total medical costs, and subcategories costs. Patients with chronic ischemic heart disease were analyzed as a highly selected subcohort. Results: For the overall group, hospital stay was significantly decreased by 2.9 days (P < 0.05) and total nitrates dosage was significantly decreased by 172.4 mg (P < 0.05) in exposed group; cost savings of pharmacy cost, examination cost, laboratory cost, operation cost and treatment was observed as significant (at P < 0.05); and the additional expenditure of Chinese patent drug (1174.9 CNY) was less than the saving of total medical costs (2636.4 CNY). For chronic ischemic heart disease subcohort, compared with unexposed group, significant decreases were also found in hospital stay and total nitrates dosage (P < 0.05); cost savings were significant (P < 0.05) for exposed group in terms of total medical costs (4339.5 CNY) and subcategories costs (including pharmacy cost, examination cost, operation cost and treatment cost); and the additional expenditure of Chinese patent drug (1189.3 CNY) was less than the saving of total medical costs. Conclusion: Compared with conventional treatment for the treatment of CHD, combination of salvianolate injection and conventional treatment was associated with a reduction in hospital stay and total nitrates dosage. The acquisition cost of Chinese patent drug (including salvianolate injection) was offset by a higher reduction in total medical costs, especially for chronic ischemic heart disease.