40-LB: The Association between Changes in Physical Activity Before and After Thyroidectomy and Incident Type 2 Diabetes in Patients with Thyroid Cancer

Abstract

Background: Thyroid cancer patients who underwent thyroid-stimulating hormone suppression therapy after thyroidectomy is increased a risk for type 2 diabetes mellitus (T2DM). However, whether the changes in physical activity (PA) before and after thyroidectomy in patients with thyroid cancer are associated with T2DM has not been evaluated yet. We investigated the association between changes in PA before and after thyroidectomy and incident T2DM in patients with thyroid cancer. Methods: An observational cohort study of 69,526 thyroid cancer patients who underwent thyroidectomy between 2010 and 2016 was performed using the Korean National Health Information Database. PA was defined as mid-term or vigorous exercise at least 1 day in a week. PA changes over time were divided into four groups: persistent non-exercisers (n = 18,441), new exercisers (n = 14,599), exercise dropouts (n = 11,023), and exercise maintainers (n = 25,463). Results: During mean 4.5 years of follow-up, the incidences per 1,000 person years of T2DM were lower in patients who performed PA before or after thyroidectomy than persistent non-exercisers (10.77 in persistent non-exerciser group, 8.28 in new exerciser group, 8.59 in exercise dropout group, and 7.61 in exercise maintainer group). Compared with the persistent non-exerciser group, the exercise dropout group (adjusted hazard ratio [aHR] 0.81, 95% confidence interval [CI], 0.72-0.91), new exerciser group (aHR 0.87, 95% CI 0.78-0.97), and the exercise maintainer group (aHR 0.84, 95% CI 0.76-0.93) had lower risks of incident T2DM. When we stratified patients according to energy expenditure, PA with < 1,500 metabolic equivalent of task (MET)-min/week in exercise maintainers was associated with lower risk of incident T2DM than non-exercisers, but PA with ≥ 1,500 MET-min/week was not. Conclusion: In patients with thyroid cancer, PA before or after thyroidectomy was associated with lower risk of incident T2DM. Disclosure J. Park: None. H. Park: None. S. Kim: None. Y. Cho: None. K. Han: None. K. Kim: None.