Continuity of care for patients with chronic lymphocytic leukemia: an analysis of real-world data

This study hypothesized that greater continuity of care (CoC) would be associated with lower all-cause healthcare resource utilization and improved overall survival (OS) among patients with chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL) among patients who received covalent Bruton tyrosine kinase inhibitor (cBTKi)-based therapy. Optum’s de-identified Clinformatics^® Data Mart Database was used for this retrospective study. Patient-level CoC measured by continuity of hematologist/oncologist provider care was evaluated using published measures; the Herfindahl-Hirschman Index (HHI) was the primary measure (range 0 = no continuity to 1.0 = complete continuity). Outcomes included all-cause emergency room (ER) visits, inpatient hospitalizations, and OS. Multivariable regression models (logistic, negative binomial, and Cox proportional hazards), adjusted for baseline covariates, were conducted to evaluate the relationship of CoC with outcomes. In total, 5,990 patients were included in the analysis; median follow-up was 31.8 months. Median HHI was 0.7210 (interquartile range = 0.4749, 1.0000). With higher CoC, there were lower odds of having an ER visit (HHI odds ratio [OR] = 0.89; 95% confidence interval [CI]: 0.87–0.91; <i>p</i> &lt; 0.0001), lower number of ER visits (HHI rate ratio [RR] = 0.93; 95%CI 0.92–0.94; <i>p</i> &lt; 0.0001), lower odds of inpatient hospitalization (HHI OR = 0.85; 95%CI: 0.84–0.87; <i>p</i> &lt; 0.0001), and lower number of hospitalizations (HHI RR = 0.89; 95%CI: 0.88–0.90; <i>p</i> &lt; 0.0001). There was no significant difference in OS (HHI hazard ratio = 0.99 (95%CI: 0.97–1.01) <i>p</i> = 0.18. Causality cannot be inferred in this retrospective study. Greater CoC was significantly associated with reduced ER visits and reduced hospitalization, among patients diagnosed with CLL who received cBTKi therapy. While interpretation may be limited in the retrospective design, sensitivity and post-hoc analyses support this relationship. The findings from this study suggest the importance of maintaining a consistent oncologist/hematologist for the patient with CLL to reduce these healthcare events; however, causality cannot be inferred from this study. This retrospective real-world database study investigated the continuity of oncology provider care among patients with CLL, to understand the relationship between continuity of care (CoC) and healthcare resource utilization and patient outcomes. This study found that higher CoC was associated with lower healthcare resource utilization, but inconsistent findings were observed with overall survival. While a causal relationship cannot be determined, these findings suggest the importance of maintaining consistent oncologist/hematologist care for the patient with CLL.