Moon JH, et al. Endocrinol Metab. 2018 Jun;33(2):278-286. https://doi.org/10.3803/EnM.2018.33.2.278

A remarkable increase in the number of thyroid cancer cases has been reported in recent years; however, the markers to predict high-risk groups have not been fully established.

Lee YK, et al. J Korean Med Sci. 2020 Oct;35(46):e403. https://doi.org/10.3346/jkms.2020.35.e403

Yi KH, et al. J Korean Med Assoc. 2015 Apr;58(4):302-312. http://dx.doi.org/10.5124/jkma.2015.58.4.302

Based on the experiences of our center, we sought to verify the necessity of actively removing stones during retrograde intrarenal surgery (RIRS) for the management of renal stones. From March 2010 to March 2015, 248 patients underwent RIRS at our center. We classified these patients into 2 groups according to the performance of active stone removal; group A (n=172) included the patients whose stones were actively removed using a stone basket, and group B (n=76) included the patients whose stones were fragmented with laser lithotripsy without active removal of the fragments. We retrospectively compared the operation time, success rate, and complication rate between the 2 groups. There were no significant differences between groups A and B in terms of mean age (56.1 years vs. 58.6 years), male to female ratio (115:57 vs. 46:30), mean body mass index (24.5 kg/m(2) vs. 25.0 kg/m(2)), mean preoperative size of stone (11.1 mm vs. 11.1 mm), the ratio of unilateral and bilateral stones (136:36 vs. 64:12), success rate (89.0% vs. 86.8%), operation time (82.5 minutes vs. 82.1 minutes), overall complication rate (9.9% vs. 11.8%), incidence of febrile urinary tract infection (6.4% vs. 2.6%), gross hematuria (1.7% vs. 2.6%), or postoperative de novo hydronephrosis (2.9% vs. 5.3%). This study demonstrated that during RIRS, fragmentation only, without the active removal of stones, is a safe and effective technique in which the surgical outcomes are comparable to those of procedures involving the active removal of stones.

Background: Studies have highlighted the adverse effects of long work hours on workers' health; however, the association of long work hours with thyroid function has not been studied. This study aimed at assessing long work hours as a risk factor for thyroid dysfunction. Methods: This cross-sectional study was based on data obtained from the Korea National Health and Nutrition Examination Survey conducted from 2013 to 2015. A total of 2160 adults who worked 36–83 hours per week were included. Thyroid function was defined based on the population thyroid-stimulating hormone reference ranges, after excluding individuals with positive results for thyroid peroxidase antibody. The association between work hours and thyroid function was confirmed via multinomial logistic regression. Results: Hypothyroidism was more prevalent among those with longer work hours (3.5% vs. 1.4% for 53–83 and 36–42 work hours per week, respectively). Individuals who worked longer hours had an increased odds for hypothyroidism (odds ratio 1.46, confidence interval 1.12 − 1.90, per 10-hour increase in work hours per week), after adjustment for age, sex, body mass index, urine iodine concentration, smoking status, work schedule, and socioeconomic status. The association between work hours and hypothyroidism was consistent in various subgroups stratified by sex or socioeconomic status. Conclusions: To our knowledge, this study is the first to show that long work hours are associated with hypothyroidism. Further large longitudinal studies are needed to clarify causality.