The choice of specific risk calculators for estimation of risk and risk threshold has been an important source of variability, ambiguity, and controversy.S8.1.2-47 S8.1.2-54 In addition, implementation of a standard (worldwide) abso- lute CVD risk threshold for initiating use of BP-lowering medications would result in large variations in medication use at a given level of BP across countries.S8.1.2-48,S8.1.2-54,S8.1.2-55 Future research in this area should focus on issues related to implementation of a risk-based approach to CVD prevention, including the use of BP-lowering medications. Although several CVD risk assessment tools are available, on the basis of current knowledge, we recommend use of the ACC/AHA Pooled Cohort Equations (http://tools.acc.org/ ASCVD-Risk-Estimator/) to estimate 10-year risk of athero- sclerotic CVD (ASCVD) to establish the BP threshold for It should be kept in mind that the ACC/AHA Pooled Cohort Equations are validated for US adults ages 40 to 79 years in the absence of concurrent statin For those >79 years old, the 10-year ASCVD risk is generally >10%, and thus the SBP threshold for anti- hypertensive drug treatment for patients >79 years old is 130 mm Hg. Two recent reviews have highlighted the importance of using predicted CVD risk together with BP to guide antihy- pertensive drug therapy.S8.1.2-22,S8.1.2-23 Figure 4 is an algorithm on BP thresholds and recommen- dations for treatment and follow-up. Recommendation-Specific Supportive Text 1. For the purposes of secondary prevention, clinical CVD is defined as CHD, congestive HF, and stroke. 