Objective This study attempted to clarify the association between participation in a social group and perceived health among elderly residents of a previously methylmercury-polluted area in Japan. Methods We conducted a cross-sectional study using eligible subjects from the Shiranui Sea coastal area, where mercury poisoning due to daily intake of fish and shellfish had previously caused some residents to develop the neurological disorder ''Minamata disease (MD).'' In the present study, we selected subjects aged C65 years who had never been diagnosed with MD or applied for medical treatment compensation.Results A logistic regression model after adjusting for confounding factors showed that membership in a hobby or volunteer group was associated with good perceived health (odds ratio 1.97, 95 % confidence interval 1.02-3.80). Conclusion Our results showed that the effects of membership in social groups on perceived health were not equal across all social groups, with only hobby-or volunteerrelated groups having a positive effect on perceived health. Our findings suggested that promoting participation in a social group such as hobby-or volunteer-related groups can help improve perceived health among elderly individuals who had experienced environmental pollution incidents.

Early, Recent, and Not Yet had lower ADL grades than Normal. Moreover, the population with a low ADL grade and health-related anxieties had increased throughout the previously methylmercury-polluted areas. The issue of ill health among populations living in previously methylmercury-polluted areas should be addressed in the wider context of public and community health.

The objective of this study was to evaluate the effect of estimated historical methylmercury exposure on the functional health of residents living in the Shiranui Sea communities in Japan. Functional health was measured by self-reported activities of daily living (ADL). Study areas were categorized into high, medium and low methylmercury exposure areas according to their location or distance from the Shiranui Sea. We estimated the adjusted prevalence odds ratios of impaired ADL in relation to exposure using a logistic regression model. Compared with residents in the low-exposure area, residents in the high-exposure area were significantly associated with a higher prevalence odds ratio (OR) for impaired ADL after adjustment for confounding factors (adjusted ORs = 2.8, 95% CI: 1.3-6.2). These results showed strong dose-response relationships (p for trend = 0.0050). Our findings suggest that historical methylmercury exposure might cause functional impairment in later in life depending on the exposure level.

Minamata disease (MD) is a neurological disorder caused by eating seafood contaminated with methylmercury, fi rst identifi ed in 1956 in Japan. However, reports of ill health related to MD increased sharply following a ruling by the Supreme Court in 2004. We performed logistic regression analyses to examine the relationship between MD specifi c socioeconomic status (MD status) and health inequalities amongst residents of Shiranui sea communities. Data were collected by two-stratifi ed sampling of residents 40-79 years old in 172 postal code areas on the Shiranui sea coast. A questionnaire was distributed to eligible subjects (n = 2100) and collected at a later visit or by mail. Two self-reported health outcomes were examined: MD-related physical symptoms (MDRS) and the 12-item General Health Questionnaire (GHQ-12). We classifi ed the 1546 respondents according to MD status: Early and Recent (received MD compensation before and after the Supreme Court decision, respectively) and Not Yet (yet to receive compensation). Adjusting for confounding factors, Early and Recent was signifi cantly associated with elevated MDRS and GHQ-12 compared with Not Yet. After further adjusting for perception of unfairness, the inequality between Early and Recent was reduced. Efforts to improve the population's health in these areas should consider health effects of MD status and perception of unfairness.

Background No studies have investigated the association between self-rated health (SRH) and high-sensitivity C-reactive protein (hs-CRP) in South Koreans. This study explored the association and analyzed any sex differences.Method Using data from the 2015-2017 Korea National Health and Nutrition Examination Survey, we analyzed the association between SRH and high group (>1.0 mg/L) in 14,544 Koreans aged ≥19 years who responded to the SRH survey and who had hs-CRP test results. Results The percentage of having a very poor to poor SRH was higher in the high hs-CRP level group (22.4%) than in the low level group (17.66%). Among males, the risk of a high hs-CRP level increased with worse SRH (adjusted for confounders; P for trend <0.001). After adjusting for all confounders, including chronic diseases, males with a very poor SRH showed higher odds ratio (OR) for high group than those with a very good SRH (fully adjusted OR, 1.74; 95% confidence interval, 1.04-2.90). Significant correlations were absent among females. Conclusions A poor SRH was correlated with low-grade inflammation (high hs-CRP level) among male Korean adults. The findings could be useful for developing health improvement programs and in goal setting at a national scale.