Regional Analysis of the Structural Availability of Physical and Rehabilitation Medicine Services Funded by the National Health Insurance Fund for Patients with Rare Diseases in Bulgaria

Background: Rare diseases are associated with chronic progression, functional impairment, and complex care needs, requiring long-term and coordinated rehabilitation. Physical and Rehabilitation Medicine (PRM) plays a key role in maintaining functional capacity and improving quality of life; however, access to rehabilitation services remains uneven across regions. Aim: This study aims to assess the regional structural availability of PRM services across Bulgaria and to identify territorial differences in the organizational profile of rehabilitation services that may influence the potential availability of rehabilitation care for patients with rare diseases. Methods: A descriptive cross-sectional study was conducted using publicly available aggregated data from the NHIF and the National Statistical Institute as of 31 December 2024. Structural indicators included the number of outpatient and inpatient PRM healthcare facilities and PRM specialists, standardized per 100,000 population, as well as the outpatient-to-inpatient facility ratio (OFs/IFs). Hierarchical cluster analysis (Ward’s method, Euclidean distance) was applied as an exploratory tool to identify similarities in regional service availability profiles. Results: Substantial regional differences in the structural availability of PRM services were identified. Outpatient facilities ranged from 4.46 to 6.74 per 100,000 population, while inpatient facilities ranged from 2.30 to 3.42 per 100,000 population. The OFs/IFs ratio varied between 1.30 and 2.26, indicating different organizational profiles of PRM service provision. Exploratory hierarchical clustering suggested two broad regional service profiles: one characterized by a relatively balanced distribution of outpatient and inpatient structures and another characterized by a predominance of outpatient-oriented rehabilitation services. Conclusion: The findings reveal substantial regional differences in the organization of PRM services in Bulgaria. Regions with a predominance of outpatient structures may demonstrate different capacities for delivering comprehensive rehabilitation services, particularly for patients with complex long-term needs, including rare diseases. The results highlight the need for targeted regional planning, improved integration of rehabilitation services, and policy measures aimed at ensuring equitable access to care.