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This study evaluates the relation between total serum cholesterol, triglycerides, and high-density lipoprotein (HDL) cholesterol, and subsequent total, cardiovascular, and cancer mortality. These data are from 4,946 US and 5,198 Polish men and women aged 35 to 64 years at baseline with mortality follow-up over 13 years. Total cholesterol showed a U-shaped or J-shaped relation to age-adjusted total and cancer mortality across all samples, with significance only in Polish women. The multivariable adjusted relative risk for total and cancer mortality was higher in the lowest cholesterol category only in Poland and significant only for cancer. Cardiovascular mortality was positively related to cholesterol, but only in Polish men and US women was mortality significantly higher in the highest versus the lowest cholesterol category. The multivariable adjusted relative risk of cardiovascular death was greater in the highest versus the lowest cholesterol category, but this trend was significant only in the US. HDL cholesterol was inversely related to total (significant only in US men) and cardiovascular mortality (significant only in US and Polish men). A similar, but not significant, association of HDL cholesterol was found with cancer mortality. The multivariable adjusted relative risk of total mortality was inversely related to HDL cholesterol significant in both the US and Poland. The relative risk of cardiovascular mortality was significantly lower at higher HDL cholesterol levels in all samples. The relative risk of cancer mortality was highest and significant at the lowest HDL cholesterol level in the US and Poland. Elevated triglycerides were associated with increased risk of total and cardiovascular mortality, but this trend was significant only in the US. Cancer mortality was not significantly related to triglycerides. The present study indicates that in geographically and culturally diverse populations, the relation of lipids with cardiovascular mortality is similar. The relation with total and cancer mortality varies by country, gender, and lipids. This suggests that relations of total and cancer mortality with lipids or lipoproteins are weaker than associations with cardiovascular mortality.

This study examines the prevalence of abnormal low-density lipoprotein (LDL) and high-density lipoprotein (HDL) cholesterol levels in young adults to determine the ability of National Cholesterol Education Program Adult Treatment Panel (ATP) guidelines to identify persons with elevated LDL cholesterol, to compare other algorithms with those of the ATP, and to determine the contributions of race, gender, and other coronary artery disease risk factors to identifying patients with elevated LDL and low HDL cholesterol. The cohort was population-based, aged 23 to 35 years, and included relatively equal numbers of blacks and whites, and men and women. The prevalence of LDL cholesterol > or = 160 mg/dl (> 4.1 mmol/L) was 5% in black women, 4% in white women, 10% in black men, and 9% in white men. ATP identified most participants with elevated LDL cholesterol (range: 58.8% of white men to 70.7% of black women). Lipoprotein panels would have been required in 6% to 7% of women and to 15% to 18% of men. Algorithms that used nonlipid risk factors required more lipoprotein panels and identified fewer additional participants at risk. The prevalence of HDL cholesterol < 35 mg/dl (0.9 mmol/L) was 3% in women, 7% in black men, and 13% in white men. Algorithms that used nonlipid risk factors before measuring HDL cholesterol would require HDL cholesterol measurements in 35% of whites and 56% of blacks, but reduced sensitivity for identifying low HDL cholesterol (range: 58% in white men to 93% in black women). In young adults, algorithms based on nonlipid risk factors and family history have lower sensitivity, and increase rather than decrease the number of fasting lipoprotein panels required when compared with ATP levels.

We compared low-density lipoprotein cholesterol (LDL) values obtained by the Friedewald formula--i.e., total cholesterol minus high-density lipoprotein (HDL) cholesterol minus very-low-density lipoprotein (VLDL) cholesterol (estimated as triglyceride divided by 5)--with those obtained by lipoprotein fractionation, using 4736 specimens. When triglycerides were less than 2.0 g/L, greater than 90% of estimated LDL cholesterol values were acceptable, within +/- 10% of measured values. At triglyceride concentrations of 2.0-4.0 g/L and 4.0-6.0 g/L, only 72% and 39%, respectively, of the estimates were acceptable. LDL values derived from an alternative formula, estimating VLDL as triglycerides divided by 6, were even less accurate. Nevertheless, the use of estimated LDL for risk classification based on the National Cholesterol Education Program Adult Treatment Panel cutpoints of 1.30 and 1.60 g/L was considered acceptable. At triglyceride concentrations less than or equal to 5.0 g/L, 88% of classifications based on estimated LDL (using triglycerides divided by 5) were concordant with those by measured LDL. Eleven percent of classifications were shifted across one cutpoint, evenly distributed between high and low. Fewer than 1% of classifications, all with Type III hyperlipoproteinemia, were misclassified two cutpoints high. Refinements in the estimation model did not substantially improve LDL estimation or concordance of risk classification.