Effect of the 2004 mid niigata prefecture earthquake on patients with endocrine disorders

A major earthquake (Richter scale magnitude 6.8) struck the Chuetsu district of Niigata Prefecture, Japan, a rural area with mountain villages, on October 23, 2004. Strong aftershocks (Grade 5-6 on the Japanese intensity scale, JIS) continued for 2 months. We analyzed the earthquake's impact on 229 patients with various endocrine disorders [6 central diabetes insipidus (CDI), 16 adrenal insufficiency (AI) including 5 panhypopituitarism, 10 ACTH isolated deficiency and 1 Addison's disease, 145 Graves' disease and 62 Hashimoto's disease]. The status of patients with CDI or AI was not adversely affected by the earthquake. Twenty-eight (19%) patients with Graves' disease developed more severe hyperthyroidism; the incidence of developing more severe hyperthyroidism increased with greater degrees of hyperthyroidism. Three (5%) patients with Hashimoto's disease developed increased TSH concentrations. Most patients stayed in their own houses following the first shock. The median PTSD total score for all patients was low. However, the PTSD total score in patients with CDI or Hashimoto's disease was significantly higher than in other patients, while the subscore of mental status in patients with AI was significantly much lower than in other patients. In patients with Hashimoto's disease, patients whose hypothyroidism worsened had higher total and environmental effects score than patients whose hypothyroidism remained stable. Comparing patients whose hyperthyroidism became more severe to those in whom it remained stable, as well as on multiple logistic regression analysis, serum TRAb was found to be a risk factor for developing more severe hyperthyroidism. In conclusion, our findings indicate that Graves' disease patients need to maintain their euthyroid state with a low serum TRAb titer to prevent the development of further thyroid dysfunction after an earthquake, and that all patients should continue to take their medication, since it is likely that their lives will be interrupted by environmental effects owing to earthquake-shock, especially patients with CDI or Hashimoto's disease. Due to the risk of medical facility closure during a disaster, all patients should always have a note or copy of their medical records, including medical history and medications used, to avoid relying on patients remembering their drug names and doses. Furthermore, appropriate information should be provided by all means possible, including the mass media, to affected individuals, particularly those with AI, to decrease the occurrence of adverse consequences.