Distribution of Outpatient Visits Among Adults With Hypothyroidism: NAMCS 2010-2019

Introduction: Hypothyroidism is a widespread chronic condition in the U.S. Gaining a comprehensive understanding of where patients with hypothyroidism seek care is critical. This study aims to estimate national trends in outpatient care visits for U.S. adults with hypothyroidism. Methods: We analyzed data from the National Ambulatory Medical Care Survey and the National Hospital Ambulatory Medical Care Survey from 2010 to 2019. Our analysis included visits for adults that were categorized by setting: primary care, medical specialty care, surgical specialty care, and emergency care. All visits associated with a diagnosis of hypothyroidism or a prescription for thyroid hormone were included. We examined 2 primary outcomes: (1) the annual mean count of visits for patients with hypothyroidism, and (2) the subset of those visits for which thyroid disease was listed as a reason for the visit. Results: An estimated 30 million primary care annual visits took place for patients with hypothyroidism, and another 15.4 million annual visits to medical specialists. Of those primary care visits, thyroid disease was a reason for visit for approximately 3.3 million visits (10.8%). Approximately 65% of all outpatient visits for patients with hypothyroidism for which thyroid disease was a reason for visit occurred in the primary care setting. Conclusion: The majority of outpatient visits for U.S. adults with hypothyroidism took place in primary care settings. These findings highlight the need to focus on primary care as a key intervention point to improve disease control in hypothyroidism.