Apathetic Hyperthyroidism — Elderly
A 68-year-old man presents with unexplained weight loss, new-onset atrial fibrillation, and mild confusion. He denies tremor, sweating, or palpitations. TSH is suppressed, FT4 is elevated. Which aspect of his presentation is most clinically relevant when considering the diagnosis of hyperthyroidism?
Correct Answer — B
This is apathetic (masked) hyperthyroidism. In patients over 65–70, the classic adrenergic symptoms (tremor, palpitations, sweating, anxiety) are often absent due to reduced beta-adrenergic receptor sensitivity. Instead, atrial fibrillation, unexplained weight loss, heart failure, or cognitive decline may be the predominant — and sometimes only — manifestations. Missing this presentation in the elderly is a common diagnostic pitfall.
Key concept
Apathetic hyperthyroidism in the elderly: absent classical signs; AF, weight loss, and heart failure may be the only features.