Smoking, Occupational Exposure, Geographic Distribution, and Familial Cancer History in Relation to Disease Burden and Cardiac Outcomes in Chronic Myeloid Leukemia: A Cross-Sectional Study

Abstract

Background & Aim: Chronic myeloid leukemia (CML) shows variable hematologic burden and cardiac complications. This study evaluated smoking and occupational exposure (modifiable), and geographic distribution and familial cancer history (non-modifiable), as predictors of disease burden and cardiac outcomes in patients with CML.
Methods: A retrospective cross-sectional study was conducted among 110 patients with confirmed chronic myeloid leukemia (CML) across participating centers from January 2025 to December 2025. Disease burden was assessed using hematologic indices, blast percentages, splenic size, and clinical severity indicators. Cardiac outcomes were assessed by transthoracic echocardiography according to a prespecified composite definition that included reduced ejection fraction, diastolic dysfunction, pulmonary hypertension, significant valvular regurgitation, or left atrial/ventricular structural abnormality. Associations were evaluated using chi-square tests, independent-samples t-tests, one-way ANOVA, correlation analysis, and multivariable regression models as appropriate.
Results: Cardiac dysfunction according to the prespecified composite definition was identified in 82 of 110 patients (74.5%). Mean EF was 63.1 ± 4.5%, and only one patient (0.9%) met the reduced-EF criterion. Grade 1–2 diastolic dysfunction was the most frequent echocardiographic abnormality (46.4%), followed by significant valvular regurgitation (24.5%) and pulmonary hypertension (9.1%). On bivariate analysis, cardiac dysfunction differed significantly across occupational exposure categories (P = 0.030), whereas no significant associations were observed with smoking, geographic residence, familial cancer history, or sex. Patients with cardiac dysfunction were significantly older than those without cardiac dysfunction (52.8 ± 14.0 vs. 29.8 ± 8.2 years, P < 0.001). In multivariable logistic regression, age was independently associated with the composite cardiac outcome (OR = 1.19, 95% CI: 1.11–1.27, P < 0.001), while occupational exposure was not independently significant.
Conclusion: In this cohort of patients with CML, age was the strongest independent factor associated with the prespecified composite cardiac outcome. Although occupational exposure was associated with cardiac dysfunction on bivariate analysis, this association was attenuated after adjustment for other covariates. The high prevalence of the composite outcome was predominantly attributable to diastolic and other echocardiographic abnormalities rather than reduced EF. Prospective studies incorporating detailed treatment exposure, cardiovascular risk factors, and longitudinal echocardiographic assessment are needed to clarify the clinical significance of these findings.