Does smoking cannabis count as smoking when calculating the Framingham Risk Score (FRS)?

Cannabis Use and Framingham Risk Score Calculation

No, cannabis smoking does not count as "smoking" when calculating the Framingham Risk Score (FRS)—the smoking variable in FRS specifically refers to cigarette smoking only. 1

Definition of "Smoker" in FRS

The Framingham Risk Score explicitly defines smoking as cigarette smoking in the past month. 1 This is the only form of tobacco use that receives points in the FRS calculation, and cannabis use is not included in this definition. 1

Why This Matters Clinically

While cannabis doesn't count toward FRS calculation, this creates a significant clinical blind spot:

• Cannabis users have substantially elevated cardiovascular risk that the FRS will not capture. Daily cannabis use is associated with 25% increased odds of myocardial infarction, 42% increased odds of stroke, and 28% increased odds of composite cardiovascular outcomes. 2

• The risk is dose-dependent: Those using cannabis ≥2 times per month have 79% increased odds of high-risk ASCVD scores, and daily users have 87% increased odds. 3

• Cannabis may be particularly harmful in non-tobacco smokers: Among never-tobacco smokers, daily cannabis use was associated with 49% increased odds of myocardial infarction and 116% increased odds of stroke. 2

Clinical Algorithm for Cannabis Users

When calculating FRS for a cannabis user:

1. Calculate the standard FRS using only cigarette smoking status (not cannabis). 1

2. Recognize the FRS will underestimate true cardiovascular risk in cannabis users, similar to how it underestimates risk in younger patients and certain ethnic minorities. 4

3. Screen all cannabis users for cardiovascular risk factors including hypertension, dyslipidemia, diabetes, and family history. 3

4. Consider the patient's cannabis use frequency when making treatment decisions:

   • Daily users: Treat more aggressively than FRS alone would suggest 3
   • Frequent users (≥2 times/month): Consider one risk category higher 3
   • Occasional users: Use clinical judgment based on other risk factors 3

5. Implement appropriate risk reduction strategies including cannabis cessation counseling, as cannabis users demonstrate increased arterial stiffness and altered cardiac mechanics even when young and otherwise healthy. 5

Important Caveats

The FRS was developed using data that did not account for cannabis use, which was not prevalent or well-documented when the original Framingham cohort was studied. 1 The cardiovascular effects of cannabis—including arterial stiffening, altered cardiac mechanics, and increased risk of arrhythmias—are independent risk factors not captured by traditional FRS variables. 6, 5

Bottom line: Calculate FRS using cigarette smoking only, but recognize that cannabis users require more aggressive cardiovascular risk assessment and management than their calculated FRS would suggest. 3, 2