Decreased Threshold for Initiating L-T ₄ Therapy in a Primary Care Population Over a 15-Year Period

BackgroundIncreased focus on well-being and quality-of-life issues in the management of various diseases has led to the earlier diagnosis and subsequent treatment of hypothyroidism in many patients seen by primary care physicians.In order to weigh the risks and benefits of thyroid hormone replacement therapy, recommendations concerning the diagnosis of hypothyroidism and initiation of levothyroxine (L-T 4 ) have been developed (1,2).The median serum TSH prompting the initiation of L-T 4 among over 52,000 individuals in the United Kingdom decreased from 8.7 mIU/L to 7.9 mIU/L between 2001 and 2009 (3), thus raising concerns about L-T 4 overuse and its potential harm.The current study (4) was performed to assess changes in thyroid hormone prescriptions for the treatment of hypothyroidism among general practitioners in Copenhagen between 2001 and 2015.