[Cut offs and risk stratification of dyslipidemia in Chinese adults]

To establish cut offs and risk stratification of dyslipidemia in Chinese adults.

Data from 2 widely cited studies: the PRC-US Collaborative Study of Cardiovascular and Cardiopulmonary Epidemiology and the China Multi-Provincial Cardiovascular Cohort Study, with a total of 40 719 Chinese adults, age 35 to 64 at baseline, about half men and half women, followed up for a total of 345 140.5 person years, were used to analyze the relationship between dyslipidemia and ischemic cardiovascular diseases (ICVD, including coronary heart events and ischemic stroke events) using a common data analysis protocol co-developed by the scientists from the 2 studies. The relative risk was estimated with the Cox proportional hazard model adjusting for other conventional cardiovascular risk factors. The 10-year absolute risk of ICVD for a 50 years-old person at different risk factor combinations was used to develop the risk stratification.

(1) There was a continuous linear relationship between baseline TC (or LDL-C) and ICVD risk without a threshold; (2) The incidence (absolute risk) of ICVD was similar for LDL-C < 3.37 mmol/L (130 mg/dl) and for TC < 5.18 mmol/L (200 mg/dl); and similar for LDL-C < 4.14 mmol/L (160 mg/dl) and for TC < 6.22 mmol/L (240 mg/dl); (3) The absolute ICVD risk for TC > or = 6.22 mmol/L (240 mg/dl) was slightly less but close to that for grade 1 hypertension; (4) ICVD risk increased as HDL-C decreased; (5) No significant association was found between baseline TG and subsequent ICVD; (6) At any TC level, the absolute ICVD risk for those having only hypertension was higher than that for those having 3 other risk factors.

The cut offs for diagnosis of dyslipidemia in Chinese adults can refer to those used in relevant international guidelines: TC < 5.18 mmol/L (200 mg/dl) [or LDL-C < 3.37 mmol/L (130 mg/dl)] as normal, TC 5.18 - 6.19 mmol/L (200 - 239 mg/dl) [or LDL-C 3.37 - 4.12 mmol/L (130 - 159 mg/dl)] as borderline high, and TC > or = 6.22 mmol/L (240 mg/dl) [or LDL-C > or = 4.14 mmol/L (160 mg/dl)] as high; HDL-C < 1.04 mmol/L (40 mg/dl) as low, 1.04 - 1.53 mmol/L (40 - 59 mg/dl) as normal and > or = 1.55 mmol/L (60 mg/dl) as optimal. In risk stratification scheme, hypertension plays a role that equals to that of any other 3 risk factors.