Profound hypothyroidism typically presenting with hypothermia, bradycardia and impaired level of conciousness.
The majority of patients presenting with myxoedema coma have long standing hypothyroidism for which treatment has been recently interrupted.
Myxoedema may be precipitated by a sudden interruption in long standing levothyroxine replacement, or rarely by the addition of interfering medications such as iron or calcium containing compounds which may delay its absorption.
Myxoedema may also be triggered by intercurrent illness such as urinary or chest infection, myocardial infarction, or stroke.
If the patient has recently moved for example into residential care, their medication may have unwittingly been changed.
Climate induced hypothermia is a common trigger for myxoedema. This is more likely to impact the elderly patient living alone in winter.
Sedation particularly with phenothiazines may precipitate myxoedema.
Dry cool skin, constipation, tiredness, weight gain and hair loss are typical features suggesting long standing hypothyroidism. See hypothyroidism pages for full assessment.
Any of these may be associated with auto-immune thyroid dysfunction.