Epidemiologic changes in thyroid disease.

Purpose of review: To analyze the evolving epidemiologic trends in thyroid disease, focusing on risk factors, underlying drivers of these changes, and their implications on clinical practice and research priorities.

Recent findings: Thyroid disease remains one of the most prevalent groups of disorders globally, and the shift in its frequency and distribution is multifactorial. The prevalence of hypothyroidism increases with age, although normal thyrotropin ranges appear to be age-dependent, raising concern for potentially inappropriate levothyroxine use. Hyperthyroidism and Graves' disease continue to be predominant in reproductive-age women but exhibit a milder phenotype at diagnosis. Thyroid nodules are increasingly found in asymptomatic patients, likely from more widespread use of neck and chest imaging. Thyroid cancer incidence has risen exponentially over the years, mostly driven by overdiagnosis of low-risk tumors; however, a small rise in incidence of higher risk tumors has been noted. Obesity appears to be a risk factor for thyroid cancer occurrence and more aggressive forms of the disease.

Summary: Understanding epidemiologic trends in thyroid disease is crucial for guiding clinical practice and research efforts, aiming to optimize patient outcomes while preventing unnecessary and potentially harmful interventions.