Quality of life and palliative care needs of patients with Niigata Minamata disease: A complete survey after 50 years since the disaster

Background: Minamata disease (MD) is caused by the ingestion of a large amount of fish or shellfish contaminated with MeHg included in industrial wastewater. In 1965, a number of cases were found along the Agano River in Niigata Prefecture in northern central Japan, which were collectively designated as “Niigata Minamata disease.” Patients with MD suffer from a set of complicated pains accompanied by various signs and symptoms. They also have mental and social pains, including loss of identity, stigmatization that leads to the refusal of friendship and marriage, and isolation in the local community. However, few studies have investigated the care and prevention measures required to relieve the symptoms of patients with MD. Aim: The objective of this survey was to investigate the symptoms, pain, and suffering experienced by patients with Niigata Minamata disease as well as their QOL and coping strategies. Design and setting: The survey was designed as a complete study of patients with MD accessible to the local government of Niigata Prefecture and that of Niigata City. Results: The average score of the study subjects in the World Health Organization Quality of Life 26 (WHO/QOL-26) was considerably lower than that of the general population, while being female and having an occupation correlated with higher scores for some domains and/or overall QOL scores. The symptoms perceived by the subjects as distressing in their daily lives included numbness in the limbs, physical pain, disturbed sensory systems, limb dysfunctions, and fatigability. The measures commonly taken to relieve these symptoms included using medicines, taking a bath/going to springs, and maintaining warmth. The common emotional support included interpersonal relationships, emotional fulfillment, selfdiscipline in daily life, and bodily health. Those certified as having MD showed no significant difference in any domains and overall QOL. Conclusions: Palliative care providers should extend their targets for non-cancer palliative care and develop approaches for MD-specific total pain.