Loss of survivorship in nasopharyngeal carcinoma attributable to fine particulate matter and its constituents.

BACKGROUND: Nasopharyngeal carcinoma (NPC) is a prevalent malignant tumor in East Asia, particularly impacting China. The association between multiple constituents of fine particulate matter (PM(2.5)) and the survival time of NPC patients remains unclear, which poses a challenge for targeted public health interventions. METHODS: An accelerated failure-time model with a 12-year cohort design was used to analyze the impact of long-term PM(2.5) and its constituents on the survival time of 1492 NPC patients. Restricted cubic splines (RCS) functions and stratification analyses were conducted to identify the exposure-response curve and vulnerable subgroups, respectively. RESULTS: PM(2.5) and its constituents were significantly associated with reduced survival time in NPC patients. For per interquartile range (IQR) increase in concentrations, the time ratio changing percentage (TRCP) ranged from -28.8 % to -33.6 % for PM(2.5), -34.7 % to -39.6 % for black carbon (BC), -13.6 % to -17.4 % for nitrate (NO(3)(-)), -21.9 % to -26.6 % for ammonium (NH(4)(+)), -29.5 % to -35.5 % for organic matter (OM), and -31.5 % to -36.2 % for sulfate (SO(4)(2-)). The exposure-response relationship exhibited a nonlinear trend, with a steep slope at lower concentrations. Furthermore, females, patients with lower monocyte levels, and those with a drinking history faced a higher risk of reduced survival time. CONCLUSIONS: The study reveals the urgent need for environmental regulations to mitigate PM(2.5) and its constituents, particularly BC. The evidence of accelerated loss of survivorship is crucial for establishing air quality guidelines concerning PM constituents and formulating public health interventions and protective measures for high-risk NPC patients.