Reynolds Risk Score (Men)

About Reynolds Risk Score (Men)

The Reynolds Risk Score for men, published by Ridker and colleagues in Circulation in 2008, is the male counterpart to the women's Reynolds Risk Score (Ridker 2007). The score was derived from 10,724 initially healthy U.S. men ≥45 years of age enrolled in the Physicians' Health Study II, with validation in 5,406 men from the same cohort. As in the female score, the development strategy was to start with traditional risk factors (age, blood pressure, cholesterol, smoking) and to test whether adding hs-CRP, parental history, and other biomarkers would improve discrimination, calibration, and net reclassification. The final model retained age, systolic blood pressure, total and HDL cholesterol, hs-CRP, smoking, and parental history of early MI. Optional extension with Lp(a) and apoB further improved reclassification in high-risk subgroups but was not incorporated into the standard published score because of limited biomarker availability at the time. The model was externally validated in the Women's Health Study, the Men's Physicians' Health Study, and multiple international cohorts.

What the calculator measures

The output is a 10-year probability of a first major cardiovascular event (nonfatal MI, ischemic stroke, coronary revascularization, or cardiovascular death). The endpoint is identical to the female Reynolds score, which allows direct comparison between sexes.

How the formula works

The male Reynolds Risk Score is a Weibull accelerated-failure-time model with the same structure as the female version but different coefficients. The published coefficients (Ridker 2008) are: 0.0663 per year of age; 1.7256 × log(SBP); 0.4944 × log(total cholesterol); -0.9754 × log(HDL); 1.3842 × log(hs-CRP); 0.8344 for current smoking; and 0.4944 for parental MI before age 60. The baseline survival function is derived from a Weibull distribution with location parameter 6.406.

Interpretation

The risk tiers mirror those of the women's score and the ASCVD Pooled Cohort Equations: <5% low, 5-10% borderline, 10-20% intermediate, >20% high. Compared with the ASCVD PCE for white men, the Reynolds male score typically gives similar results in the low and high range but reclassifies 20-30% of intermediate-risk men, half upward (driven by elevated hs-CRP or parental history) and half downward (driven by low hs-CRP and clean family history).

Clinical use

The male Reynolds Risk Score is most useful in the intermediate-risk range, where reclassification can change statin decisions. The 2018 ACC/AHA cholesterol guideline lists hs-CRP ≥2 mg/L and family history of premature ASCVD as 'risk-enhancing factors' that can tip the balance toward statin initiation in intermediate-risk patients; the Reynolds score formalizes this by integrating these factors into a single probability. The Reynolds score is also valuable for men with strong family histories that are not fully captured by traditional risk factors, and for men with low hs-CRP whose Framingham or ASCVD risk may overestimate true risk.

Limitations

The Reynolds score was derived in a predominantly white, male, physician cohort (Physicians' Health Study) and is not well validated in other racial groups. It requires an hs-CRP measurement, which adds cost and is not universally available. As with the female score, hs-CRP can be elevated by acute inflammation (infection, autoimmune flare, recent exercise); values >10 mg/L should be repeated after 2-4 weeks. The score does not include diabetes, antihypertensive treatment status, or race, three variables that are in the ASCVD PCE, which can lead to discrepancies in diabetics, treated hypertensives, and African American men.

Comparison with ASCVD

For most white men in the intermediate-risk range, the ASCVD PCE and the Reynolds score agree within 2-3 percentage points. Major discrepancies are most often driven by hs-CRP and parental history. When the two scores disagree, the Reynolds score is generally considered the more accurate individual-level estimate because it incorporates two additional validated risk markers; however, the ASCVD PCE remains the guideline-endorsed tool for statin decisions in the United States, and the Reynolds score should be used as an adjunct rather than a replacement.

How to use the result

A Reynolds Risk Score of 12% means approximately 12 out of 100 men with similar risk factors will have a major cardiovascular event in the next decade. The clinical conversation should focus on modifiable risk factors: smoking cessation, blood pressure control, statin therapy for elevated LDL-C, Mediterranean-style diet, and 150 minutes per week of moderate-intensity exercise. For men reclassified upward from intermediate to high risk, the conversation should escalate to high-intensity statin therapy with a goal of at least 50% LDL-C reduction.