Association between blood pressure and serum lipids in a population. The Tromso Study. BACKGROUND. High blood pressure has been associated with elevated atherogenic blood lipid fractions, but epidemiological surveys often give inconsistent results across population subgroups. A better understanding of the relation between blood pressure and blood lipids may provide insight into the mechanism(s) whereby hypertension is associated with increased risk of coronary heart disease. METHODS AND RESULTS. We assessed the cross-sectional relations of serum total cholesterol, high density lipoprotein (HDL) cholesterol, non-HDL cholesterol (total minus HDL cholesterol), and triglyceride levels with blood pressure in a population of 8,081 men 20-54 years old and 7,663 women 20-49 years old. Stratified analyses and multivariable methods were used to control for potential confounding anthropometric and lifestyle variables. Total and non-HDL cholesterol levels increased significantly with increasing systolic or diastolic blood pressure in both sexes. Men 20-29 years old had steeper regression slopes for blood pressure by total cholesterol level than did women of similar age. In men, the association between blood pressure and total cholesterol level decreased with age, whereas in women, it increased with age. Body mass index modified the relation, whereas smoking, physical activity, and alcohol consumption had little influence on the association. Triglyceride levels increased with blood pressure, but this relation was weak in lean subjects. HDL cholesterol level correlated positively with blood pressure in population subgroups having a high alcohol consumption. CONCLUSION. These results support the hypothesis that there are biological interrelations between blood pressure and blood lipids that may influence the mechanisms whereby blood pressure is associated with risk of coronary heart disease. 