Ayres J, Rees J, Clark T J, Maisey M N
Clin Endocrinol (Oxf). 1982 Jan;16(1):65-71. doi: 10.1111/j.1365-2265.1982.tb03148.x.
Shortness of breath is a common symptom in thyrotoxicosis and it may have a number of causes. We have studied dyspnoea, skeletal muscle power and respiratory muscle power in eleven patients who had thyrotoxicosis with no evidence of heart failure. Four patients (36.4%) had a marked improvement with treatment in the maximal inspiratory pressure developed at the mouth. All four were breathless and had a proximal myopathy before treatment. This confirms the existence of a group of thyrotoxic patients with a reversible respiratory muscle myopathy which may explain the frequent finding of breathlessness on exertion in such patients.
