Managing thyroid disease in general practice
Thyroid disease can be broadly categorised as thyroid dysfunction (hypothyroidism, hyperthyroidism) and structural disease (goitre, nodules and cancer). Management is often straightforward, but there are pitfalls that may lead to misdiagnosis, overdiagnosis and inappropriate treatment. This article reviews the approach to common thyroid problems in general practice.
Worldwide, iodine deficiency is the most common cause of thyroid disease. Iodine deficiency has long been known in Tasmania, and a survey published in 2006 found evidence of iodine deficiency in mainland Australia, particularly New South Wales and Victoria.1 In 2009, use of iodised salt in bread became mandatory in Australia and New Zealand (following a Tasmanian program started in 2001), and Australia is now considered iodine sufficient.2
Autoimmune thyroid disease is the commonest cause of thyroid dysfunction in Australia, with prevalence as shown in Box 1. Some 10–15% of the population have positive thyroid antibodies, most commonly to thyroid peroxidase (TPOAb), with a higher prevalence in women than men.3 Patients who are euthyroid with positive thyroid antibodies do not require treatment, but are at increased risk of thyroid dysfunction (particularly hypothyroidism),4,