Hypocalcaemia following thyroidectomy for treatment of Graves' disease: implications for patient management and cost-effectiveness.

BACKGROUND

No consensus exists on optimal treatment for Graves' disease once anti-thyroid medication fails to induce remission. Total thyroidectomy is a more cost-effective treatment than radioactive iodine or life-long anti-thyroid medication, but hypocalcaemia is an important complication, leading to longer hospital admissions and increased prescription costs. This study aimed to compare the relative risk of hypocalcaemia requiring medical treatment for patients with Graves' disease.

METHODS

Prospective cohort study of patients undergoing total thyroidectomy for Graves' disease and for multinodular goitre, calculating serum calcium levels 24-hours post-operatively and prescription rates.

RESULTS

Mean corrected calcium concentrations 24 hours post-operatively were 2.05 mmol/l for Graves' disease patients and 2.14 mmol/l for multinodular goitre patients (p = 0.003). Biochemical hypocalcaemia developed in 92 per cent (n = 34) of Graves' disease patients and 71 per cent (n = 43) of multinodular goitre patients (p = 0.012). Graves' disease patients were more likely to be prescribed calcium supplementation pre-discharge (p = 0.037).

CONCLUSION

Total thyroidectomy for Graves' disease carries an increased risk of hypocalcaemia at 24 hours, and of calcium supplementation pre-discharge. Graves' disease patients should be informed of the increased risk of hypocalcaemia associated with total thyroidectomy, and this risk must be factored into future cost-effectiveness analysis.