Abstract
BACKGROUND: Thyroid cancer (TC) incidence is rapidly increasing, ranking as the third most common cancer in China. This study aimed to investigate the association between light at night (LAN), air pollutants, and TC risk among the rural population in Fujian Province, China, from 2012 to 2016. METHODS: This study utilized 23,111 first reimbursement records of TC patients from the New Rural Cooperative Medical System (NRCMS) in Fujian Province between 2012 and 2016 to calculate county-level hospitalization rates. The performance of geographically weighted regression (GWR), multiscale geographically weighted regression (MGWR), and geographically and temporally weighted regression (GTWR) models were compared to identify the best model for investigating the effects of LAN, nitrogen dioxide (NO(2)), ozone (O(3)), urbanization, and number of medical and technical personnel per 1000 population (NMTP) on the hospitalization rates of TC in 74 counties. RESULTS: TC hospitalization rates exhibited an initial increase followed by a decline, with higher rates in eastern coastal and southern regions. Spatial clustering was observed (Global Moran's I: 0.152-0.284). The GTWR model performed best (R(2) = 0.821), showing positive correlations between LAN, NMTP, and TC, while urbanization was negatively correlated. LAN had a strong effect on TC in the north, while NMTP had a strong effect in the east. NO(2) and TC remained positively correlated in all regions except the south, and O(3) was consistently positively correlated with hospitalization rates in the southern region and the eastern seaboard. CONCLUSIONS: LAN, NO(2), O(3), urbanization, and NMTP exhibit significant spatiotemporal associations with TC risk in the rural population of Fujian Province. Targeted interventions are needed to reduce the TC burden based on regional risk factors.