Thursday, October 23, 2014

IS VIAGRA GOOD FOR THE HEART?


Viagra is a popular drug, frequently used in Malaysia as treatment for erectile dysfunction. That is the medical indication. However, many young men are using it as a tonic for sexual enhancement.
Now, they are asking , if I should take Viagra often ( chronically for some ) will it harm my heart.
Well, a recent study by the Italian group seemed to suggest that it surely does not harm the heart but in fact may help the heart. It that true?
This issue was highlighted in the lay press recently showing that it is of public interest. So I thought that I should have a look at it.
The study is an Italian one, published in the BMC Medical, 19th Oct 2014. The Article is entitled " Is chronic inhibition of Phosphodiaesterase Type 5 cardioprotective and safe? A meta-analysis. This Italian group from the Sapienza University of Rome, went into the medical data base of Medline and Embase to look over 24 RCT involving PE 5 inhibitors usage from 4 weeks to 1 year, where cardiac indices were also measured. There were 1,622 patients deemed suitable. 954 were on PD 5 inhibitors and 772 were on placebo. They were enrolled from March 2012 till Dec 2013.The indications for PD 5 usage was not clear. They researchers only wanted all patients to have placebo control and also to have taken PD 5 inhibitors chronically. Most of the patients were taking sildenafil citrate ( viagra ). Fewer were taking Levitra and Cialis.
They concluded from their meta-analysis ( which had a lot of statistics ), that PD 5 was safe to use chronically. That there was some improvement in LV function indices, that it helped the heart with LVH to remodel better, that with usage in patients with heart failure, the pro-BNP estimation improved, and there was also better peripheral vasodilation.

So I had a look at the paper. It must have been a big ask to take so many diverse study and try and match them together. There were many variables. I did not know how the investigators were able to analyse the data coherently. Yes, there was improvement in LVEF but it was in the region of 3-4%, and they were using echocardiogram as a means of determining the LV function. Surely, 3-4 % may not be significant. The methodology to measure vaso-motion was not detailed.
All in all, in my opinion, a rather weak study, using statistics to mesmerise us. Drawing big poster concusions based on rather flimsy data.

I am quite sure that it is safe to consume PD 5 inhibitor chronically but remember NOT to use it together with GTN. If used chronically, it may reduced Pulmonary artery resistance and improve RV function somewhat. As for improvement in LV function, we should take that with a large pinch of salt.

To be certain, we will have to wait for more data, and more evidence.

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