K_Man

Apr 26, 12 17:46

Views: 961
K_Man wrote:

For example, the CVD 30-year risk calculator shows that a 40-year-old man with 159 total / 50 HDL has an 11% chance of developing full CVD in 30 years, whereas a 40-year-old man with 200 total / 50 HDL has a 14% chance of developing full CVD in 30 years. That's a 3% difference in risk over the 30 years. I understand that, for some people, that difference may not be significant.

BZZZZZZZZZZZZT, fail. Do not pass go, do not collect \$200. You've completely missed the point, which is that the HDL/LDL (or, in this case, HDL/total) ratio is a more important predictor of risk than total cholesterol. By comparing 159/50 to 200/50, well no shit you get an increased risk because the HDL/total ratio is lower as well as total cholesterol being higher. If you want to isolate risk factors, don't change two things at once!

Your 159/50 (and I'm assuming you picked 159 vs. 160 so that the calculated risk score, which has a breakpoint at 160, would be lower...) corresponds to the same ratio as 200/63. I'll let you plug the numbers into the Framingham 30-year CVD calculator to see how they turn out (I'll give you a hint: it's not the way that supports your assertions).

I chose 159 merely because the Framingham study indicated that there are no risk points for a total cholesterol of _under_ 160. You make a good point that I should've kept the ratios the same to eliminate the ratio as being a factor in the calculation. However, as you pointed out in your next post, there is a potential difference of up to 3% that is attributable to total cholesterol alone. A person with a total cholesterol of 100 has a 3% less risk over 30 years than a person with a total cholesterol of 300 even when they have identical ratios, correct? I don't think I've missed the point at all.

(This post was edited by K_Man on Apr 26, 12 18:08)

 Edit Log: Post edited by K_Man (Cloudburst Summit) on Apr 26, 12 18:04 Post edited by K_Man (Cloudburst Summit) on Apr 26, 12 18:08