Thyroidectomy for Graves' disease: is hypothyroidism inevitable?

The outcome of 234 patients with Graves' disease treated by subtotal thyroidectomy over a 12-year period is analysed with specific reference to hypothyroidism. Of definite hypothyroid cases, 98% occurred within 2 years. Failure to develop hypothyroidism was statistically related to large remnant size and a large goitre preoperatively. Histological review showed that any degree of lymphocytic infiltration was associated with the development of hypothyroidism (50% vs 22%). Late onset hypothyroidism occurred rarely and is not an inevitable outcome of thyroid surgery in our hands.