Abstract
BACKGROUND: There is accumulating evidence of an association between particulate matter smaller than 2.5 μm (PM(2.5)) and cancer. However, the impact of air pollution on the survival of lymphoma patients has received little attention. METHODS: This retrospective study was conducted at Henan Cancer Hospital. We included lymphoma patients admitted between January 2017 and December 2020, with follow-ups conducted via telephone. Daily gridded data on PM(2.5) and its chemical components were obtained over a 10 km × 10 km grid. To assess the association between PM(2.5) levels and lymphoma mortality, we employed a Cox proportional-hazards model. Additionally, a restricted cubic spline function was used to evaluate nonlinear associations between chemical components and 1- and 2-year PM(2.5) exposure levels with lymphoma survival. Finally, a multi-pollutant analysis using quartile-based g-calculation was performed to estimate the joint association of PM(2.5) and chemical component exposure with mortality. RESULTS: The 1-year PM(2.5) exposure level was positively associated with the risk of lymphoma death, as were its chemical components. In contrast, the 2-year PM(2.5) exposure level showed no significant association with lymphoma mortality, although its components exhibited a positive correlation. In a multi-pollutant joint effects analysis, 1-year exposure to organic matter (OM) was associated with lymphoma mortality (HR: 1.56; 95% CI: 1.01-2.40), while 2-year exposure to black carbon (BC) was also associated with increased mortality risk (HR: 1.82; 95% CI: 1.10-3.02). CONCLUSIONS: Exposure to PM(2.5) may adversely affect the survival of lymphoma patients. Further studies, including mechanistic investigations and clinical trials, are needed to validate this association. Additionally, lymphoma patients may benefit from residing in areas with good air quality after diagnosis, as this could potentially improve their survival outcomes.