Association of serum cholesterol with cardiovascular disease and malignant tumor: 7-year folllow-up to 698 796 people

Aim: To study the association of serum cholesterol level with the mortality risk of cardiovascular diseases and malignant tumor, and investigate the best range of cholesterol level. Methods: Totally 698796 people aged 40 and above, who were guaranteed in Korea Medical Insurance Company between 1992 and 1993, were followed up for 7 years. The adjusted relative risk of different cholesterol levels with mortalities of all causes, cardiovascular disease and malignant tumor was calculated and analyzed with Cox proportional hazards model. Results: Serum cholesterol levels showed a U-shaped association with the adjusted relative risk of mortalities of all causes, cardiovascular disease and malignant tumor. The risk of mortality was all increased when the cholesterol level was lower than 4.0 mmol/L or higher than 6.0 mmol/L. Serum cholesterol level was negatively correlated with malignant tumor, the higher the serum cholesterol level, the lower the risk of malignant tumor. Conclusion: Lower serum cholesterol level increases the risk of mortalities of cardiovascular disease and malignant tumor. Higher serum cholesterol level increases the risk of cardiovascular disease mortality. The serum cholesterol level ranged 4.5 to 5.5 mmol/L is an ideal level.