Geographic disparities in the care and outcomes in adult chronic immune thrombocytopenia

Abstract

Introduction: Despite expert-based recommendations, real-world adherence to immune thrombocytopenia (ITP) guidelines is unclear. The impact of geographic and socioeconomic disparities on the quality of care and outcomes is unknown. We sought to determine the association between geographic remoteness and material deprivation on ITP care and outcomes.

Methods: We conducted a multi-centre retrospective cohort study of adults with chronic ITP requiring a second-line therapy between 2012 and 2019 in the province of Alberta, Canada. Socioeconomic status was measured using the Pampalon material deprivation index quintiles. Geographic disparities were assessed by the driving distance to a major centre, with geographic remoteness defined as >200 km from major centre. We examined the impact of geographic and material deprivation on quality of care, resource utilization (hospitalizations, transfusions), and outcomes (major bleeding, all-cause mortality and ITP-related mortality). Cox proportional hazards models were used to examine the impact of geographic remoteness, rural residence and material deprivation on overall survival and ITP-related survival.

Results: We included 326 ITP patients, median age of ITP diagnosis was 57 years, 182 (56 %) were female. Most patients (58 %) lived within 20 km of a major centre, whereas 49 (15 %) lived in a geographically remote area (>200 km). Geographic remoteness was significantly associated with material deprivation and lower likelihood of management by hematologists (84 % vs 99 %, P = 0.0001). It was also associated with lower rates of hepatitis C (71 % vs 89 %, P = 0.005) and hepatitis B testing (69 % vs 86 %, P = 0.03), and a non-significant trend towards lower rates of HIV testing (73 % vs 83 %, P = 0.051) compared with those <20 km from a major centre. Incomplete hyposplenic vaccinations among splenectomized patients (52 %), early splenectomy within 12 months of ITP diagnosis (35 %), inappropriate platelet transfusions (41 %), and inappropriate hospitalizations for asymptomatic thrombocytopenia (16 %) were common regardless of geographic distribution. There were 28 (9 %) ITP-related deaths (major bleeding or infections), most occurred within the first year of ITP diagnosis. Material deprivation, but not geographic remoteness, was an independent predictor of all-cause mortality (aHR 1.9, 95 % CI 1.1-3.3 in the most deprived quintile vs least deprived quintile). Rural residence trended towards increased hazard of ITP-related deaths (aHR 1.7, 95 % CI 0.9-3.2).

Conclusion: We demonstrated substantial deviations of ITP care from consensus guidelines, and geographic disparities in access to care and diagnostic workup. Future quality improvement initiatives are critical to improve the quality of care and reduce inequities.

Keywords: Healthcare disparities; Hemorrhage; Immune thrombocytopenia; Mortality; Quality of care; Socioeconomic factors.