Clinical characteristics and outcome of thyroid storm: a case series and review of neuropsychiatric derangements in thyrotoxicosis.

OBJECTIVE: The objectives of this study were (1) to describe the presentation, demographics, and clinical course of patients admitted for thyroid storm, and (2) to identify factors associated with mortality.

METHODS: A retrospective review of subjects admitted to a single academic hospital from 2006 through 2011 was conducted. Medical records for all patients who were admitted with a diagnosis of thyrotoxicosis were systematically reviewed for clinical features of thyroid storm.

RESULTS: A total of 28 cases were identified. Thyroid storm was the first clinical presentation of thyrotoxicosis in 13 patients (46.4%). Noncompliance with treatment was a major trigger in previously diagnosed patients, followed by infection. The mortality rate was 25% in this series. Cardiac manifestations were predominant, with >60% of patients having severe tachycardia (heart rate >140 beats per minunte) and/or atrial fibrillation. Although central nervous system (CNS) involvement was less frequent (n = 8, 28.6%), CNS derangement of worse than mild severity was statistically associated with mortality (P = .021). There was good agreement between the Burch-Wartofsky Point Scale and Japanese Thyroid Association criteria in the diagnosis of thyroid storm in this study cohort.

CONCLUSION: Thyroid storm was the first presentation of thyrotoxicosis in a significant proportion of patients, highlighting the importance of a high index of suspicion in an appropriate clinical context. The presence of neuropsychiatric manifestations appeared to portend greater risk of mortality. Prevailing evidence suggests that there are complex interactions between thyroid hormones and neurotransmitter circuits in the pathogenesis of CNS symptomology in thyrotoxicosis.