Myxedema coma is most likely to occur in patients with which condition?

Myxedema coma is a severe, life-threatening complication associated with untreated hypothyroidism. In this condition, the body is unable to produce enough thyroid hormones, which are crucial for regulating metabolism, energy levels, and overall physiological functions. During myxedema coma, the severe deficiency of thyroid hormones can lead to significant alterations in mental status, hypothermia, and a host of systemic issues.

In patients with untreated hypothyroidism, the metabolic processes slow down dramatically, leading to symptoms such as extreme fatigue, weight gain, depression, and sensitivity to cold. If not addressed, these symptoms can escalate to a myxedema coma, where patients may present with altered mental status, respiratory depression, and cardiovascular collapse.

The other conditions listed do not lead to myxedema coma. Excess thyroid hormones can cause hyperthyroid symptoms but would not result in the severe hypothyroid state characterizing myxedema coma. Treatment-resistant hypertension is unrelated, as it deals primarily with blood pressure management rather than thyroid hormone levels. Finally, diabetes mellitus, while it has its own complications, is not directly connected to the severe thyroid hormone deficiency seen in myxedema coma. This highlights why untreated hypothyroidism is the condition most closely associated with this critical emergency.