Framingham Risk Score (FRS) included age, gender, body mass index (BMI), cigarette smoking, blood pressure, total cholesterol (TC), LDL-cholesterol (LDL-C) and diabetes mellitus (DM). Previously, Framingham cohort study and other study has confered patients with medium or high FRS had worse prognosis. However, the score list was tending to over-estimate risk in medium FRS or under-estimate risk in high FRS patients . For this reason, ACC/AHA cholesterol guidelines also recommend the use of additional markers to improve atherosclerotic cardiovascular disease (ASCVD) risk assessment and medical decision making.

Meanwhile, the ABI, which was the ratio of systolic pressure at the ankle to that in the arm, was quick, easy and used to diagnosis and assess the severity of peripheral artery disease (PAD) in the legs. Several research have shown its low value as an indicator of general atherosclerosis and independently risk associated with cardiovascular events in prospective studies . In addition, ABI aggressively modified risk factors and accelerated the adverse prognosis of ASCVD. However, whether FRS or ABI, were all related to participants and race. And, most studies were from western countries, lack of Asian date, especially aimed at risk prediction model research. Therefore, this research was aimed to validate incorporating ABI and relevant Framingham risk variables whether could improve prediction all-cause mortality and cardiac mortality in medium and high Framingham risk score (FRS) patients.

The study is a longitudinal cohort study. The first cross-sectional survey was conducted in 2011.

The inclusion criteria:

1. Patients were age older than or equal to 18 years
2. Patients with medium and high Framingham risk score，namely, Framingham Risk Score (FRS) 10%-20%,or FRS > 20%.
3. All participants gave written informed consent to this study, which was approved by the ethics committee of Tongji University.

Exclusion Criteria:

1. Patients were suffering from mental illness.
2. Life expectancy of patients were less than 1 year.

There were 3687 participants from multi-central departments with multiple classical Framingham risk factors atherosclerosis, including 1935 males and 1752 females whose age older than or equal to 18 years. All participants were followed up from November 2011 to June 2018. A total of hospitalized patients were consecutively enrolled from cardiology department and under treatment because of cardiovascular diseases .