Endocrine Abstracts

Objective: Subacute thyroiditis (SAT) is a transient inflammatory disease of the thyroid. As we hypothesized that clinical characteristics of SAT were changing recent years, we evaluated data of our patients.

Patients and methods: We retrospectively reviewed the medical records of 192 patients (45 men and 147 women) with SAT who visited our hospital from 1990 to 2009. We analyzed these records dividing into two groups by decade, i.e. the first 10 years (1990–1999) and the following 10 years (2000–2009).

Results: In each decade, female patients were 50/65 (76.9%) vs 97/127 (76.4%), more than 50-year-old patients were 29/65 (44.6%) vs 71/127 (55.1%), CRP higher than 5 mg/dl was observed in 25/60 (41.6%) vs 49/127 (38.6%), and F-T₄ higher than 3 ng/dl was observed in 38/65 (58.5%) vs 69/127 (54.3%). Ratio of older patients tended to increase in the second decade (P=0.13). We noticed that seasonal distribution of SAT onset changed in two decades. In the first decade, SAT onsets were often seen in spring. On the other hand, in the second decade, the peak in spring became less remarkable and onsets between late summer and autumn were increased. Onsets between August and October in each decade were 16/65 (24.6%) vs 50/127 (39.4%), and significant difference was observed (P=0.04).

Conclusion: We observed that seasonal distribution of SAT onset changed. SAT was generally considered to be developed by viral infection, so this alteration may be due to the transition of viral environment.

Declaration of interest: The authors declare that there is no conflict of interest that could be perceived as prejudicing the impartiality of the research project.

Funding: This research did not receive any specific grant from any funding agency in the public, commercial or not-for-profit sector.