Causes of death among patients diagnosed with chronic lymphocytic leukemia: A population‐based study in the Netherlands, 1996–2020

Chronic lymphocytic leukemia (CLL) manifests heterogeneously with varying outcomes. This population-based study examined causes of death (CODs), as registered by the physician who established the death, among 20,588 CLL patients diagnosed in the Netherlands between 1996 and 2020. Utilizing cause-specific flexible parametric survival models, we estimated cause-specific hazard ratios (HRs) and cumulative incidences of death due to CLL, solid malignancies, other hematological malignancies, infections, and other causes. Our findings reveal CLL as the predominant COD, contributing to around 40% of relative mortality, with a declining 5-year death probability from 16.8% in 1996-2002 to 7.6% in 2010-2020. Also, deaths attributed to solid malignancies, other hematological malignancies, and other COD diminished over time, as evidenced by respective HRs (95% confidence interval) of 0.68 (0.60%-0.77%), 0.45 (0.38%-0.53%), and 0.77 (0.66%-0.90%). In summary, our comprehensive, population-based analysis underscores a noticeable reduction in CLL-attributed deaths and other competing causes over the studied period. Nonetheless, CLL is registered as the most prevalent cause of mortality among contemporary diagnosed patients with CLL, emphasizing the continued relevance of CLL-centric clinical strategies and research.