Hashimoto’s Thyroiditis is an Important Risk Factor of Papillary Thyroid Microcarcinoma in Younger Adults

The association between autoimmune thyroid disease and thyroid cancer remains unclear. We performed a matched case-control study to assess the association between Hashimoto’s thyroiditis and papillary thyroid microcarcinoma (PTMC). A total of 927 PTMC cases and 927 age- and gender- matched controls selected from the same population were recruited. Odds ratio (OR) with 95% confidence interval (95% CI) was used to assess the strength of the association between Hashimoto’s thyroiditis and PTMC. Conditional logistic regression analysis was carried out, and stratified analyses by age, gender and types of thyroid antibodies were also performed. Hashimoto’s thyroiditis was significantly associated with increased risk of PTMC (OR=1.87, 95% CI 1.49–2.34, p