Comorbidities at Diagnosis, Survival, and Cause of Death in Patients with Chronic Lymphocytic Leukemia: A Population-Based Study

Abstract

Leucèmia limfocítica crònica; Comorbiditat; Causes de mort

Chronic lymphocytic leukemia; Comorbidity; Cause of death

Leucemia linfocítica crónica; Comorbilidad; Causas de muerte

This study aimed to examine the prevalence of comorbidities in patients diagnosed with chronic lymphocytic leukemia (CLL), and to assess its influence on survival and cause-specific mortality at a population-based level. Incident CLL cases diagnosed in the Girona province (Spain) during 2008-2016 were extracted from the Girona Cancer Registry. Rai stage and presence of comorbidities at diagnosis, further categorized using the Charlson comorbidity index (CCI), were obtained from clinical records. Observed (OS) and relative survival (RS) were estimated and Cox's proportional hazard models were used to explore the impact of comorbidity on mortality. Among the 400 cases included in the study, 380 (99.5%) presented at least one comorbidity at CLL diagnosis, with diabetes without end organ damage (21%) being the most common disease. 5-year OS and RS were 68.8 (95% CI: 64.4-73.6) and 99.5 (95% CI 3.13-106.0), respectively, which decreased markedly with increasing CCI, particularly in patients with CCI ≥ 3. Multivariate analysis identified no statistically significant association between the CCI and overall CLL-related or CLL-unrelated mortality. In conclusion, a high CCI score negatively influenced the OS and RS of CLL patients, yet its effect on mortality was statistically non-significant when also considering age and the Rai stage.

We thank CERCA programme/Generalitat de Catalunya for institutional support. Thiswork was supported by Spanish Ministry of Economy and Competitiveness—Carlos III Instituteof Health co-funded by FEDER funds/European Regional Development Fund (ERDF)—A way tobuild Europe (PI11/02213, PI15/00966 and CIBERESP); and with the support of the Secretariat forUniversities and Research of the Ministry of Business and Knowledge of the Government of Catalonia(2017-SGR-733). IDIBGI is a member of the CERCA Programme, Generalitat de Catalunya.