Association between steatotic liver disease subtype and thyroid cancer in women: A nationwide population-based cohort study

Objective This study aimed to investigate association between steatotic liver disease (SLD) subtype and thyroid cancer in women using a nationwide population-based cohort. Methods This nationwide population-based cohort study included 2,089,609 women aged more than 40 years who participated in the 2009 health screening program and were followed up until 2022. Participants were divided into four groups based on their SLD status: no SLD, metabolic dysfunction-associated steatotic liver disease (MASLD), metabolic dysfunction and alcohol-related liver disease (MetALD), and alcohol-related liver disease (ALD). Results During a mean follow-up of 12.27 years, 40,072 (1.92%) women were newly diagnosed with thyroid cancer. Compared with the no SLD group, women with MASLD had a higher risk of thyroid cancer (hazard ratio [HR]: 1.19, 95% confidence interval [CI]: 1.16-1.22), whereas those with MetALD and ALD did not have a higher risk. The risk of thyroid cancer was higher in women with MASLD, including both premenopausal (HR: 1.21, 95% CI: 1.16-1.26) and postmenopausal women (HR: 1.17, 95% CI: 1.14-1.21). Women in the MetALD group showed no risk elevation of thyroid cancer regardless of their menopausal status. Postmenopausal women in the ALD group had a higher risk of thyroid cancer than those in the no SLD group (HR: 1.31, 95% CI: 1.05-1.64), whereas premenopausal women did not have a higher risk. Conclusions Thyroid cancer risk was modestly increased in women with MASLD, whereas no significant associations were observed for MetALD or ALD.