This small pilot study suggests a ratio of 1.3 in mmol terms as the threshold to stay under. That converts to 3.0 in mg/dl terms.
Hi Alan, I've revived this thread because I came across an American link on the subject of ratios that recommends using HDL/Total C ratio as well as Trigs/HDL. I've never seen this mentioned before and on my Australian results it always shows Total C/HDL (ideal < 3.5) as the risk factor calculation. Was wondering if you'd ever heard of this before?
Also, would the mmol ratio be any different to the mg/dl ratio (I assume that as it's a US site, they'd be discussing those units):
Also, if it's not too complicated (maths is not one of my strong suits) why would the ratio change because the units used for the calculation change? I just can't get my head around why a conversion would be necessary?
Your input would be appreciated
Total/HDL is the common ratio which also appears on my lab reports; usually showing a target <4 on mine.
The trigs/HDL ratio is supposed to give an indication of the level of nasty dense particles in your LDL but the total/HDL does not do that. I'm not quite sure what it indicates apart from being better if HDL is high; I don't think it matters much if an inverse is used. Bear in mind it is skewed by HDL being part of the total. I used to get non-HDL/HDL which is probably more valuable, but still gives no indication of fluffy versus dense in the LDL.
It would be far simpler if they actually measured the dense LDL particles. I'm not a lab tech so I don't know why they don't do that.
The units change because of different mg/dl and mmol/l conversions for the lipid components.
- Divide Triglycerides in mmol/l by 0.0114 to get mg/dl. Thus 1 mmol/l = 88.5 mg/dl
- Divide other lipids (LDL, HDL, Total) in mmol/l by 0.0259. Thus 1 mmol/l = 38.6 mg/dl
Therefore, a ratio of 1.3 in mg/dl terms for trigs/HDL = 1.3 x 88.5 / 38.6 = 2.98 = ~3.0 in mmol/l terms.