Distance to specialized care predicts emergency department, pain infusion clinic, and inpatient utilization patterns in adults with sickle cell disease

Abstract Background: Adults with sickle cell disease (SCD) often experience fragmented or crisis-driven care. While geographic distance from specialized centers is often cited as a significant barrier to access, its specific impact on different types of healthcare service use—such as emergency department (ED), pain infusion clinic, inpatient, and outpatient visits—remains poorly quantified. This study aimed to characterize how residential distance from a specialized SCD care center influenced real-world healthcare utilization patterns by type of service. Methods: We analyzed visit data from patients residing within 100 miles of a specialized SCD care center, grouped in 10-mile increments: 0-10, 10-20, 20-30, 30-40, 40-50, 50-60, 60-70, 70-80, 80-90, 90-100. Visit counts were examined for four service types: ED, pain infusion clinic, inpatient, and outpatient visits. Zero-inflated Poisson regression models were used to assess associations between distance and utilization rates for each service type. Predicted mean visit counts were compared across distance groups, with statistical significance determined by z-tests and p-values < 0.05. Results: Healthcare utilization varied significantly by distance from the medical center. However, the patterns of variation were complex and heterogeneous by service type. Patients living 30–40 or 40-50 miles away exhibited the highest predicted ED use, with mean visit counts of 18.96 and 39.78, respectively. ED utilization was significantly influenced by distance for 52% of individuals living 10–70 miles away (p<0.05). Pain infusion clinic utilization peaked at 80–90 miles away (mean visits = 12.12), followed by a secondary peak at 0–30 miles away (p<0.05). Further, among individuals living 0–30 miles away, 64% varied significantly in pain infusion clinic use based on distance (P < 0.05). Somewhat similar to pain infusion clinic use, the highest inpatient utilization occurred in the group living 70–80 miles away, with a predicted mean of 5.2 visits, compared to 2 visits for the next group of distance. In total, 62% of patients residing 10–40 and 60–70 miles from the center had inpatient visits significantly affected by distance. Last, outpatient visit patterns varied inconsistently across distance groups. Predicted visit counts ranged between 9 and 13, but the distribution appeared random by distance. Overall, 54% of patients varied significantly in their outpatient visit frequency by distance, while 46% showed a notable distance effect specifically between 20–40 miles. Outpatient visists peaked at 20-30 miles away (mean visits =13). In particular, patients living within 0–10 miles of the center demonstrated relatively high pain infusion clinic usage but lower ED reliance, suggesting a shift from crisis-driven to scheduled pain care when living in close proximity to a specialized SCD care center. Conclusions:Distance from aspecialized SCD care center is a key driver of SCD healthcare utilization patterns. Patients living 30–50 miles from the center exhibit the highest reliance on ED services, while those farther away—particularly at 80–90 miles—use more episodic pain infusion clinic services, possibly reflecting deferred or crisis-based care. These findings underscore the need for specialized SCD care centers to develop tailored, distance-sensitive SCD care delivery solutions, especially for pain care. Examples include mobile care units, decentralized service networks, or a hub-and-spoke care model, to reduce access disparities and support proactive continuity of care for individuals with SCD. Kanter J, Smith WR, Desai PC, Treadwell M, Andemariam B, Little J, Nugent D, Claster S, Manwani DG, Baker J, Strouse JJ, Osunkwo I, Stewart RW, King A, Shook LM, Roberts JD, Lanzkron S. Building access to care in adult sickle cell disease: defining models of care, essential components, and economic aspects. Blood Adv. 2020 Aug 25;4(16):3804-3813. doi: 10.1182/bloodadvances.2020001743. PMID: 32785684; PMCID: PMC7448595.