Myxedema madness: psychosis in patients with untreated hypothyroidism

Abstract

Hypothyroidism - a frequent endocrine pathology that affects approximately 3.6% of the population and manifests as bunch of clinical symptoms, which usually includes fatigue, unintentional weight gain, dry skin, edema, myalgia, constipation, cold intolerance. A chronically under-active thyroid can lead to neuropsychiatric symptoms like cognitive impairment, depression, agitation or even psychosis (“myxedema madness”). The diagnosis of myxedema psychosis (MP) is a significant challenge leading to potential oversight of an underlying hypothyroid etiology. The aim of this literature review is to summarize the latest research on the etiology, risk factors and clinical features of “myxedema madness” and show the importance of recognising it's causes. The phenomenon first described as “myxedema madness” was by Asher in 1949, who detailed 14 case reports of individuals with psychotic symptomatic in conjunction with myxedema. Literature shows that most often MP can be found in patients with Hashimoto thyroiditis, after total thyroidectomy or inappropriate use of thyroid medication. “Myxedema madness” with cognitive impairment occurs in hypothyroidism due to the accumulation of glycosaminoglycans in the body's tissues, and it is worth noting that schizophrenic patients also have a higher average glycosaminoglycan concentration. The amygdala and hippocampus contain high concentrations of thyroid triiodothyronine (T3) receptors, which have a direct influence on neural activity. Hypothyroidism is associated with increased brain dopamine and tyrosine hydroxylase activity, and a similar increase in subcortical dopamine is seen in schizophrenic patients with positive symptoms. The most common psychiatric symptoms of MP were delusions, disorder of drive and activity, formal thought disorder and disorder of perception. Hypothyroidism-induced psychotic states are sometimes associated with disturbances in orientation, such as delirious states, but are more often psychotic and well oriented at the same time, as in schizophrenia and mania. However, individual descriptions of Capgras-Syndrome, self-disorder, and manic syndromes suggests that any kind of psychopathology may occur. “Myxedema madness” is a rare but reversible psychotic state, which shows that recognition of thyroid dysfunction in psychotic patients is essential. This work raises awareness among healthcare professionals and could help improve patient outcomes and reduce healthcare costs associated with misdiagnosis.