Intersection of Pain-Related Healthcare Utilization with Neighborhood Factorsin Adults Living with Sickle Cell Disease

Introduction.Sickle cell disease (SCD) is the most commonly detected genetic disorder on newborn screening, leading to severe morbidity and early mortality. People with SCD account for more than 230,000 annual hospitalizations costing $2.4 billion and an extraordinarily high 30-day hospital readmission rate of 36.1%. About 95% of hospitalizations are due to painful vaso-occlusive episodes. People with SCD experience severe episodic and chronic pain which contributes to acute care visits and hospitalizations. Access to primary care and community pharmacies is key to controlling pain and overall disease management for people with SCD (Kanter et al., 2020). Community access to primary care and pharmacies is restricted by residential segregation which disproportionally limits access to those resources (Gaskin et al., 2012). The existing body of work examining neighborhoods among people living with SCD is limited to primarily child-focused studies and largely overlooks pain-related outcomes. To our knowledge, no study has comprehensively examined associations between multiple neighborhood characteristics and pain-related outcomes in communities where people with SCD live.

Purpose. The study examined the associations between neighborhood-level factors and pain-related outcomes among people living with SCD.

Methods. The study merged individual-level data from Examining Sickle Cell Acute Pain in the Emergency vs Day Hospital study participants (n=482) in Baltimore, Cleveland, Milwaukee, and Baton Rouge with neighborhood-level data (Lanzkron et al., 2018; Lanzkron et al., 2018). Study exposures are a standardized residential segregation score that measures Black-white extremes, number of pharmacies, number of physicians, distance from SCD infusion center, number of public transit stops, percent of households without cars, medication adjustments, Emergency Department (ED) visits, infusion center visits, and hospital admissions. Mixed-effects Poisson models were used to account for random effects within individuals and to account forpotential correlation within zip codes. Models adjusted for age, current hydroxyurea use, disability status, employment status, gender, hematologist and primary care provider status, education attainment, income, SCD genotype, residential status, health insurance type, and whether they experienced daily chronic pain.

Results. The study included 482 participants residing in 169 neighborhoods. Ninety-seven percent were Black, 61% female, and average age 34 years. On average, participants had 2.5 admissions (3.3 SD), 6.6 ED visits (10.4 SD), and 6 infusion center visits (11.4 SD) during the 18-month study period. Residing in a neighborhood with more pharmacies (IRR=6.05, 95% CI: 1.27, 28.7) and more transit stops (IRR=0.86, 95% CI: 0.79, 0.93) were associated with more and less medication adjustments respectively. Neighborhood racial segregation (IRR=0.42, 95% CI: 0.24, 0.73) and neighborhood race-income extremes (IRR=0.38, 95% CI: 0.18, 0.80) were significantly associated with fewer admissions in the bivariate analysis. Neighborhood distance from the infusion site was significantly associated with fewer admissions (IRR=0.99, 95% CI: 0.98, 0.99) in the bivariate analyses. After adjusting for demographics, healthcare access, and clinical characteristics, increases in neighborhood distance to the study site were associated with a decrease of both infusion center visits (IRR=0.97, 95% CI: 0.96, 0.98) and ED visits (IRR=0.99, 95% CI: 0.98, 0.99).

Conclusions. Among people with SCD, living in areas with more white residents compared to black residents and areas of higher concentration of high-income white residents compared to low-income black residents are associated with fewer hospital admissions. The data suggests that residential segregation deserves additional study within the context of land use, resource allocation, and urban development. Additionally, living farther away from care was associated with less health utilization. This may suggest a need to expand access to high quality care to more remote locations. Further analysis is required to determine if increased medication adjustments' association with greater number of pharmacies enables appropriate care utilization. Overall, greater attention should be paid to the neighborhoods in which people with SCD live their daily lives.

Lanzkron:Bluebird BIo: Membership on an entity's Board of Directors or advisory committees; Novo Nordisk: Membership on an entity's Board of Directors or advisory committees; Pfizer: Consultancy; Merck: Consultancy; Novartis: Consultancy; Agios: Membership on an entity's Board of Directors or advisory committees; GMI: Consultancy; Takeda: Research Funding; GBT: Research Funding; CSL-Behring: Research Funding; PCORI: Research Funding; HRSA: Research Funding; Pfizer: Other: Stock in Family trust; Teva: Other: Stock in Family trust.