A woman with a history of subtotal thyroidectomy for Graves' disease presents with hyperlipidaemia. What is the most appropriate initial treatment?

In this scenario, the woman has hyperlipidaemia and a history of subtotal thyroidectomy for Graves' disease, which suggests she may have hypothyroidism as a result of the surgery. Hypothyroidism is known to contribute to metabolic changes, including alterations in lipid metabolism, potentially leading to hyperlipidaemia.

The administration of levothyroxine is the most appropriate initial treatment because this hormone replacement therapy addresses the underlying cause of her hyperlipidaemia, which is likely related to inadequate thyroid hormone levels. Restoring normal thyroid function with levothyroxine can help normalize lipid metabolism and potentially reduce her lipid levels over time.

The other treatment options, such as statins or fibrates, are aimed at managing hyperlipidaemia directly but do not treat the underlying issue of thyroid hormone deficiency. Therefore, initiating levothyroxine therapy not only targets the lipid disorder but also addresses the root cause related to her past thyroid surgery, making it the most suitable choice in this context.