Clinical and socioeconomic predispositions to complicated thyrotoxicosis: A predictable and preventable syndrome?

PURPOSE: To identify the clinical, demographic, and hormonal features that characterize and place patients at greater risk for complicated thyrotoxicosis. PATIENTS AND METHODS: Fifty-nine patients with documented thyrotoxicosis complicated by cardiovascular, neuropsychiatric, gastrointestinal, or thermoregulatory dysfunction, were retrospectively identified among 498,000 hospital admissions between 1979 and 1992. Clinical, demographic, and hormonal information were obtained from these charts, as well as from the charts of 118 randomly selected thyrotoxic outpatients. RESULTS: Age distribution of complicated thyrotoxicosis patients was bimodal, with a median of 41 years. Forty-nine percent of patients had been previously diagnosed with thyrotoxicosis, but most had been noncompliant with prescribed medication. Cardiovascular complications were among the primary causes for admission in 46% of patients, followed by neuropsychiatric indications in 42%, fever in 34%, and gastrointestinal dysfunction in 17%. Only 8% had primary involvement of >2 organ systems. There was high correlation between organ systems with pre-existing dysfunction and those with a complication of thyrotoxicosis (P< 0.0001). Compared to uncomplicated controls, patients with complicated thyrotoxicosis were more likely to be uninsured or covered by Medicaid (OR, 2.64; 95% CI 1.78 to 3.91); to be <30 or >50 years old (OR, 1.93; 95% CI 1.23 to 3.03); and to have serum T4 concentrations greater than twice the upper limit of normal (OR, 1.67; 95% CI, 1.15 to 2.44). CONCLUSIONS: Certain thyrotoxic patients are at greater risk for developing complications. By addressing the medical needs of these patients, it may be possible to reduce the likelihood of complications requiring hospitalization.