• Dates: 2025-12-21 - 2025-12-21
  • Status: finished
  • Importance: 5

I was asked to look into the benefits of statins for reducing cardiovascular risk in your 60s (if you have 1-2 cardiovascular risk factors: e.g. high blood pressure and say ~130 mg/dL LDL cholesterol). Here is my summary estimate of quantified benefits:

  Without statins With statins
Yearly chance of stroke 0.50% 0.40%
Yearly chance of heart attack 0.80% 0.50%
Yearly chance of death from any cause 1.30% 1.20%

Methodology

This is mainly based on a quick review of the US Preventive Services Task Force recommendation on statins, their corresponding meta-analysis of studies on statins, and a Lancet 2010 study.

According to the US Preventive Services Task Force:

In pooled analyses, statin therapy was associated with decreased risk of all-cause mortality (18 trials; n = 85,816; relative risk [RR], 0.92 [95% CI, 0.87 to 0.98]; absolute risk difference [ARD], −0.35%), fatal or nonfatal stroke (15 trials; n = 76,610; RR, 0.78 [95% CI, 0.68 to 0.90]; ARD, −0.39%), and fatal or nonfatal myocardial infarction (12 trials; n = 76,498; RR, 0.67 [95% CI, 0.60 to 0.75]; ARD, −0.89%). In several trials, primary outcome was reported as a composite of CVD events, with the exact components of this end point varying across trials. In a pooled analysis of 15 trials, statin therapy was also associated with a decreased risk of composite cardiovascular outcomes (n = 74,390; RR, 0.72 [95% CI, 0.64 to 0.81]; ARD, −1.28%).

Based on this and an average surveillance time of ~3 years for cardiovascular events in those studies, I converted the relative risks and absolute risk differences into raw rates of events in each group:

  • All-cause mortality: probability_in_control_group = 0.35% / .08 = 4.4%. So statins reduced to .92 * 4.4% = 4%. Yearly this becomes 1.3% to 1.2%.
  • Stroke: probability_in_control_group = 0.39% / .22 = 1.8%. So statins reduced to .78 * 1.8% = 1.4%. Yearly this becomes 0.5% to 0.4%.
  • Heart attack / myocardial infarction (MI): probability_in_control_group = 0.89% / .33 = 2.7%. So statins reduced to .67 * 2.7% = 1.8%. Yearly this becomes 0.8% to 0.5%.

I wanted to check this against the Lancet 2010 study. That study compares “more intensive” against “standard” statin regimens. It says:

  • Standard statin regimens (20–40 mg simvastatin daily) reduce 120 mg/dL LDL cholesterol to say 80 (by a third).
  • More intense regimens (e.g. 40–80 mg atorvastatin or 10–20 mg rosuvastatin daily) reduce that to say 60 (by a half), or 20 points more than the standard regimens.
  • Each 40 point reduction of LDL cholesterol is worth a 10% relative risk reduction in all-cause mortality, and each 20 point reduction is worth say a 13% RR reduction in MI and 16% RR reduction in stroke.

This is reasonably consistent with the USPSTF numbers if we say the USPSTF-reviewed studies are standard statin regimens reducing LDL cholesterol by 40 points (by squaring the 13% and 16% RRs, e.g. .87^2 = .76 and .84^2 = .71).