Association between a regional reimbursement policy and treatment escalation in pulmonary arterial hypertension: a real-world cohort study with long-term Markov cost-effectiveness analysis.

Background: Pulmonary arterial hypertension (PAH) requires long-term treatment with high-cost targeted therapies. However, evidence regarding the associations of reimbursement policies with real-world treatment escalation and long-term economic outcomes remains limited. Objectives: To examine the association between implementation of a regional reimbursement policy and real-world treatment patterns and to evaluate the long-term cost-effectiveness of the observed post-policy treatment distribution compared with the pre-policy distribution. Methods: A retrospective single-center before-and-after cohort study including 147 patients with PAH was conducted using real-world data from a tertiary hospital in China. Descriptive analyses and multivariable logistic regression were used to examine factors associated with ambrisentan use and combination therapy. A lifetime Markov model incorporating World Health Organization functional class states was developed to compare the observed treatment distributions before and after policy implementation from the Chinese healthcare system perspective. During each model cycle, the time spent in each World Health Organization functional-class state was weighted by the corresponding health utility to calculate quality-adjusted life-years (QALYs). Results: Following policy implementation, the proportion of patients receiving combination therapy increased from 27.4% to 80.5% (P < 0.001). Policy implementation and ambrisentan use were both associated with receipt of combination therapy, although the policy association was attenuated after adjustment for ambrisentan use. Compared with the pre-policy treatment distribution, the post-policy distribution generated an incremental gain of 0.51 quality-adjusted life years (QALYs) at an additional cost of ¥1,212,269, resulting in an incremental cost-effectiveness ratio (ICER) of ¥2,378,493/QALY. Sensitivity analyses demonstrated that the results were primarily influenced by mortality and utility parameters associated with World Health Organization functional class IV (WHO FC IV). Cost-effectiveness was achieved only when targeted therapy prices were reduced by approximately 90%. Conclusion: Implementation of the reimbursement policy was associated with substantial changes in real-world treatment patterns among patients with PAH, including increased use of combination therapy. However, under current drug pricing conditions, the post-policy treatment distribution was not cost-effective from the Chinese healthcare system perspective. Substantial reductions in targeted therapy prices may be necessary to improve the economic feasibility of intensified combination treatment strategies.