Association between Cadmium and Cognitive Function in the Elderly / 대한산업의학회지

OBJECTIVES: We conducted this study to investigate the relationship between the blood concentration of cadmium and cognitive function in elderly Koreans. METHODS: This research is a part of the Korean Elderly Environmental Panel Study (KEEPS). A total of 403 subjects were enrolled and analyzed from August 2008 through August 2010. Demographic information and medical histories were obtained using a questionnaire. Blood concentration of cadmium and Mini-Mental State Examination (MMSE) with Functional Activities Questionnaire (FAQ) were evaluated for each subject. RESULTS: The mean age of subjects was 70.67 (SD 5.18, n=403) and 72% were female. The mean blood cadmium level was 1.22 microg/dl (SD 0.56), mean MMSE score was 25.12 out of 30 and mean FAQ score was 2.03 out of 30. Using linear regression analysis to estimate the relationship between blood cadmium concentration and MMSE and FAQ, we observed a significant association between log transformed values of blood cadmium levels and MMSE (p<0.002) or FAQ (p=0.005) scores. After adjusting for age, sex, level of education, alcohol consumption and smoking habits, the relationship between blood cadmium concentration and MMSE and FAQ scores ramained statistically significant (p=0.033 and 0.029, respectively). CONCLUSIONS: These results suggest that blood cadmium concentration is strongly associated with cognitive function and functional activity in the elderly.

Relationship Between Urinary t, t-muconic Acid and Insulin Resistance in the Elderly / 대한산업의학회지

OBJECTIVES: To examine the associations between the urinary t, t-muconic acid (t, t-MA) concentration and three indices of insulin resistance; namely, the homeostasis assessment of insulin resistance (HOMA-IR) index, blood insulin level and fasting glucose level. METHODS: A panel study was performed on the elderly at a public health care center population in the northern area of Seoul between 2008 and 2010. The participants were 560 elderly, over 60 years of age whose urinary t, t-MA and insulin resistance indices had been measured; questionnaires were completed by these participants. A generalized linear mixed (GLM) analysis was adjusted for age, sex, drinking, urinary cotinine, exercise, vitamin intake and body mass index, at a significance level of p<0.05. RESULTS: A total of 411 participants were finally analyzed after excluding those with diabetes and only one visit to the public health care center. Higher urinary t, t-MA concentrations were linearly associated with the HOMA-IR index, blood insulin level and fasting glucose level in the simple and fully adjusted GLM models. Although there were few limitations, a portion of insulin resistance was proven to be explained by exposure to benzene using r-squared. A significant relationship was also observed between urinary t, t-MA and malondialdehyde (MDA) using the same GLM models. CONCLUSIONS: Urinary t, t-MA is related to the development of insulin resistance which is a key factor for development of diabetes and its complications induced by oxidative stress.