Wednesday, November 13, 2013

So every male over 65 will be on Statins now?

The AHA's new guidelines tell us anyone with a 10 yr risk of MI over 7.5% should be on Statins.

I ran the 10-Year Risk Calculator Results on a pretty healthy 65 yo male:

Total Cholesterol: 180 mg/dL

HDL Cholesterol: 45 mg/dL

Smoker: No

Systolic Blood Pressure: 130 mm/Hg

On medication for HBP: No

Risk Score: 12%

12% is more than 7.5% -- by a good margin. By way of comparison, I'm 54, do CrossFit, lead an abstemious life, and my risk is   still 4%.

So following these guidelines would mean almost all men over 60 will be on statins. There's reason to suspect that's a bad idea. Personally I'd note that anti-inflammatory agents are often associated with increased malignancy rates, and that statins alter neuronal lipids - which is certain to be a mixed bag.

I want to see what the US Preventive Services Task Force has to say.

PS. Years ago, while studying for my board exams,  I wrote about a problem with our risk models notes:

The risk estimation guidelines are a mess, because they combine two different models -- a Framingham data based model (Bayesian, see NHLBI risk calculator) and a predictive risk factor model. Diabetes and Family History, for example, are a part of the 2nd and missing from the Framingham model -- probably because the data was not recorded. LDL is estimated in the Framingham model from HDL and total cholesterol, but is a part of the risk factor approach

This is not good. A 48 yo male with fifteen years of diabetes, but good BP, non-smoker and not-too-bad lipids wouldn't get Statins from the Framingham model, but they would from the Risk Factor model.

In the new AHA/ACA's guidelines they pull all the diabetics out -- they go on statins regardless of their risk score. But the Framingham model, as best I can tell, included diabetic patients. So its risk scores ought to be much higher than the true risks for a cohort that excludes diabetes ...

No comments: