To study diffrences in dietary factors among communities with different living environments, we carried out a survey by the Cardiac Study method in 241 people (106 men and 135 women) aged between 50 and 54 years who were selected by random sampling from a total of 37, 000 inhabitants in a small city. The city was geographically divided into town, flatland farming area, and mountainous farming area, and the results of the survey were compared among these areas.
The mean Na excretion in 24-hour specimens of urine was slightly higher in the mountainous farming area than in the other two-areas. The mean serum total cholesterol was higher in men in the town than in those in the other areas.
Factor analysis of the data for nutrient intake patterns revealed a lower fat intake in the two farming areas than in the town in the men, and a higher intake of animal foods in the town and a lower fat intake in the mountainous area in the women.
These results show that risk factors for circulatory diseases such as urinary Na excretion, serum cholesterol level, and nutrient intake patterns differ even among small areas if the living environment differs.

BACKGROUNDSeveral studies have suggested that the exposure to cadmium (Cd) increased mortalities from renal diseases, cardiovascular diseases and malignant neoplasm, including lung cancer and prostate cancer among inhabitants living in Cd-polluted areas and factory workers. This study aimed to assess the influence of environmental exposure to Cd on long term outcome of inhabitants living in an area polluted by Cd.

METHODSA 22-year follow-up study was conducted with 3119 inhabitants (1403 men and 1716 women) living in the Cd polluted Kakehashi River basin in Japan. The subjects were divided into 4 groups according to the amount of urinary Cd level (< 3.0 µg/g creatinine (Cr), 3.0 - 4.9 µg/g Cr, 5.0 - 9.9 µg/g Cr, and ≥ 10.0 µg/g Cr). Mortality was calculated by the person-years method. Hazards ratios (HR) and 95% confidence intervals (CI) were assessed by the Cox's proportional hazard model.

RESULTSCompared with urinary Cd < 3.0 µg/g Cr group, the HR of 5.0 - 9.9 µg/g Cr and ≥ 10.0 µg/g Cr groups were significantly increased after adjustment for age in both sexes: 1.24 (95%CI 1.01 - 1.51) and 1.48 (95%CI 1.17 - 1.90) for men; 1.64 (95%CI 1.17 - 2.28) and 1.78 (95%CI 1.27 - 2.50) for women. The most frequent cause of death was malignant neoplasm in men and cardiovascular diseases in women. The significant increase in mortality risk for cardiovascular diseases was observed in the subjects with ≥ 10 µg/g Cr in both sexes: 1.79 for men (95%CI 1.02 - 3.12) and 2.38 for women (95%CI 1.11 - 5.07). When the subjects were divided into 2 categories (< 20 µg/g Cr and ≥ 20 µg/g Cr), the HR of the urinary Cd ≥ 20 µg/g Cr group for nephritis and nephrosis were 4.82 (95%CI 1.07 - 21.61) in men and 7.92 (95%CI 1.77 - 35.33) in women, respectively. The significant increase was not observed for malignant neoplasm.

CONCLUSIONThese results suggest a dose-response relationship between Cd body burden and mortality for cardiovascular diseases, cerebrovascular diseases and nephritis and nephrosis.

Aged ; Aged, 80 and over ; Cadmium ; toxicity ; Cardiovascular Diseases ; mortality ; Cerebrovascular Disorders ; mortality ; Environmental Exposure ; adverse effects ; Female ; Follow-Up Studies ; Hazardous Substances ; Humans ; Japan ; Male ; Middle Aged ; Nephritis ; mortality ; Nephrosis ; mortality ; Proportional Hazards Models ; Risk Factors