I am 43 year old male who has a history of anxiety and depression. I'm currently taking 30mg of citalopram and 1.0 mg of clonazepam.

I started the 30mg dose of citalopram two weeks ago. Before that, I was on 20mg for quite a few years. I feel like the citalopram dosage increase is helping and my family doctor said that it might even make sense to go to 40mg.
I asked her if that might be getting a bit high since the FDA has issued a warning about high dosages of citalopram being related to QT prolongation. She said that 40mg is fine, and even 60mg would be OK.
I thought that was a strange thing to say since the FDA warning is clear that 60mg doses should be avoided.

But, I recently discovered this link which seems to indicate the FDA warning may have been premature:
http://www.ncbi.nlm.nih.gov/pubmed/23640689

I have no history of heart issues, nor do I fall into any of the risk categories the FDA describes. So, should I be at all concerned about an increase to 40mg. I want to be very cautious since I've not had a major depressive episode in at least 5 years, but I find I still need to stay on medication or my anxiety and mood do start to get worse.

I would appreciate some feedback on this.