Online Tool to Assess Cardiovascular Risk with Abacavir (Epzicom, Kivexa)

[edfu]

http://www.aidsmap.com/page/1518618/

[Assurbanipal]

Eep! 

I guess a quick heart attack beats lingering kidney failure, but if I don't post for an extended period...


The number needed to harm (NNH)* for abacavir and given patient profile is 82
This means that you need to treat 82 patients with the cardiovascular risk profile as stipulated below to observe an MI in one additional patient as a consequence of abacavir treatment only over a 5 year period of using abacavir.
The underlying Framingham 5-years risk for the specified patient profile is 1.4% and the absolute Framingham 5-years risk while on abacavir is 2.6%
Please note that the abacavir related risk of MI has been assumed to be constant over time and equal to an 90% increase in the underlying risk.

[edfu]

Eep! 

Eep!  Eep!  Eep!

My NNH came in at 35!!!  Underlying Framingham 5-years risk:  3.2%.  Absolute Framingham 5-years risk:  6.1%. 

I'm going to have to discuss this with my ID M.D.  It has me very worried now.  I've been taking abacavir for 9 years, first in Trizivir and then in Epzicom, with good results and no side effects. 

[newt]

Basically what this calculator tells you is that abacavir nearly doubles your risk of heart attack, as per the DAD study findings. If you baseline risk is low, then this may not matter, if it's high, or you have underlying risk factors, eg diabetes, smoke the risk will be higher.

Duh!

Obviously, underlying risk factors increase your chance of heart attack, and abacavir is just an additional factor to consider.

Therefore I find the headline "Individual risk factors crucial in determining a patient's risk of heart attack if taking abacavir" slightly disingenuous.

For people eg with poor kidney function it might be a rock and hard place choice between abacavir and tenofovir because poor kidney function is a risk factor for heart disease.

Framingham score is a good tool and everyone should do it once it year. It is not validated for people with HIV, but gives an approximate indication of general risk.

It remains a constant that stopping smoking is the biggest modifiable risk factor and much more important than abacavir/no abacavir to risk of heart attack (tenofovir taking smokers like me take note...).

Number needed to harm (NNH) is a difficult concept to grasp. It's a population level concept, and while 1 in 1,000 or so might look like low odds from a personal perspective, in countries like South Africa where it's abacavir or AZT/d4T, and there is a high incidence of diabetes and smoking is common, this may mean 100s of unnecessary deaths.

NNH of below 1 in 100 is basically serious for the individual.

Who'd be happy with a 5-year risk of heart attack of 15%, or wanna be the 1 in 7 people who copped it cos of abacavir? Who'd wanna choose between screwed heart or screwed kidneys? Alas this is an everyday choice for many people on ARVs.

- matt

Now playing: Killing Me Softly, Shirley Bassey

[newt]

Edfu, just to say, if the DAD study is right, stopping abacavir makes an almost instant adjustment to the risk score.

[edfu]

This is really interesting, although I certainly was aware of it:

I went back to the tool and changed only one variable.  Puff, puff.  I checked off non-smoker instead of smoker.

My result this time was an NNH of 128, and the two Framingham percentages changed from 3.2% to 0.9% and from 6.1% to 1.7%.

The lesson is obvious, but I have been stubborn.  My habit has lasted for 50 years.   

[Miss Philicia]

Still smoking Eddie?  That gives me hope.

[newt]

Like a lush, me

[edfu]

Ooooh.  For a second there I thought this had morphed into the "I Love Porn" thread.   

[newt]

Useful link:

University of Edinburgh cardiovascular risk calculators (no abacavir, if taking abacavir mulitply by 1.9 for heart attack (MI) only)

http://cvrisk.mvm.ed.ac.uk/calculator/calc.asp

Validated for general polulation.

- matt

[elf]

My total cholesterol is high (6.5mmol/L) although HDL and LDL are normal because
along with Epzicom/Kivexa I'm also taking Kaletra. And not even Lovaza and Niacin
can lower my total cholestero. Oh well.  


w/o Kivexa: Probability of developing cardiovascular disease in next 10 years is 2%
(thank you Kaletra!)

w/Kivexa: 3.8 %
(thank you Kivexa!)