Association of low plasma cholesterol with mortality for cancer at varioussites in men: 17-y follow-up of the prospective Basel study

Background: Low serum cholesterol has been associated with an increased ris k of cancer mortality in various studies, which has led to uncertainty rega rding the benefit of lower blood cholesterol. Objective: The: aim of our study was to evaluate the association between lo w blood cholesterol (< 5.16 mmol/L) and cancer at sites that have rarely be en evaluated. We placed special emphasis on the potential confounding effec t of antioxidant vitamins. Design: Plasma Concentrations of cholesterol and antioxidant vitamins were measured in 1971-1973 in 2974 men working in Basel, Switzerland. In 1990, t he vital status of all participants was assessed. Results: Two hundred ninety of the participants had died from cancer, 87 fr om lung, 30 from prostate, 28 from stomach, and 22 from colon cancer. Group means for plasma cholesterol concentrations did-not differ significantly b etween survivors and those who died from cancer at any of the studied sites . With plasma cholesterol, vitamins C and E, retinol, carotene: smoking, an d: age accounted for in a Cox model, an increase in total cancer mortality in lung, prostate, and colon bur not in stomach cancer mortality: was obser ved in men >60 y of age with low plasma cholesterol. When data from the fir st 2 y of follow-up were excluded from the analysis, the relative risk esti mates remained practically unchanged with regard to lung cancer but decreas ed for colon, prostate, and overall cancer. Conclusions: Increased cancer mortality risks associated with low plasma ch olesterol were not explained by the confounding effect of antioxidant vitam ins, but were attributed in part to the effect of preexisting cancer.