March 28, 2013
Over in Clinical Infectious Diseases, a recent study pretty much nails the fact that routine measurement of CD4 cell counts in clinically stable patients is an all but useless exercise. As summarized by Abbie Zuger in Journal Watch, here's the key finding:
When patients with an unrelated cause for an alteration in CD4-cell count such as severe infection, chemotherapy, or interferon treatment were excluded from the analysis, not a single patient in any group had a dip in CD4 count below 200 cells/mm3 after 2 years of continuous virologic control.
So I've been singing this tune for a while (large nose-enhancing video here), and as a result have been trying for some time to get my stable patients to reduce the frequency of CD4 monitoring -- or even, as I note in this editorial, give it up entirely!
And has this been a successful effort? For some patients, yes, but for others it's hopeless -- they simply can't understand that this test, which was the cornerstone of HIV monitoring for decades, now provides us with information that has no role in determining what we do therapeutically (provided the viral load remains suppressed).
In short, we order the test for emotional and sentimental reasons only -- it's reassuring to patients to hear that their CD4 cell count is stable, and we've been doing it for so long, why stop now. But are these good enough reasons? Before you answer in the affirmative, remember that unexplained drops in CD4 (which are not uncommon) have the opposite effect, and require frequent education about why the result won't change our patients' treatments.
So I ask you, providers of HIV care, the following burning question:
How often do you measure CD4 cell counts in your stable patients with long-term virologic suppression?
[Editor's note: You can vote on this poll and view results by visiting the original blog post.]
Paul Sax is Clinical Director of Infectious Diseases at Brigham and Women's Hospital. His blog HIV and ID Observations is part of Journal Watch, where he is Editor-in-Chief of Journal Watch AIDS Clinical Care.