Serum concentration of selenium in healthy and malignant diseased population

Abstract

Preliminary researches taken part in Yugoslavia showed the risky low level of selenium (Se) in soil, food items and in serum of the examined population; therefore the aim of this research was to discover the specific factors which could influence the serum concentration of selenium and the appearance of malignant diseases. The case-control study included the group of malignant diseased patients from urban and rural regions of Belgrade and the group of healthy pairs matches the group of diseased subjects in sex and age and not blood related. We followed the serum concentration of selenium using the method of atomic absorption spectrophotometry on spectrophotometer Perkin-Elmer model 5000. We also used an interview in order to discover different factors that can influence the serum concentration of selenium and the appearance of malignant diseases, like nutrition status by 'food frequency' method, risky behavior such as: smoking, alcohol consumption, use of toxic chemical compounds. The differences in average values of serum concentration of selenium between diseased and control subjects were not statistically significant, but both were below the lowest noticed in all previous reports. We also noticed the significant difference between subjects from rural and urban communities: The lowest level of Se was found in patients with breast cancer. Factors that showed the most significant influence on malignant diseases tested by logistic regression (shown odds ratios) were dwelling conditions and intake of some food items. On the contrary: smoking, alcohol consumption, chronic diseases, use of toxic chemical compounds didn't show statistically significant correlation with malignant disease. The levels of Se of our subjects were classified in quartiles by using 35 variables in the method of canonic discrimination analyses. So these results showed the multifactorial nature. Among these factors, the most significant were those connected with dwelling place (flat dimension and comfort), health parameters, frequency of using 15 food items (milk and milky products, fish, poultry, vegetables, fruit), food supplying. We made a conclusion that modification of nutrition in with more regular meals, more cereals intake, fruit, vegetables, fish and poultry (food with great amount of selenium) as well as using food from different regions of the country, should have double positive influence on prevention of low Se and elimination the negative nutritional habits which are risky factors for malignant diseases. The usefulness of fertilizers enriched with selenium should be seriously considered.