How Much Screening Do Modern Therapies Warrant?
Chief Medical Editor
In this issue, Dr Scott Elman addresses a fascinating, practical, and important clinical question: What monitoring is appropriate for patients on biologic treatment? This is always a question that relies heavily on physicians’ good judgment. Screening comes with direct costs, as well as the indirect costs of false-positive results and the potential morbidity from further testing that accompanies false-positive tests.
Even though we may have some evidence to go on, we will likely never have the clinical trials that randomize our patients to different screening regimens to tell which way to screen patients is best. Such studies would need enormous sample sizes to detect a difference in group outcomes for the rare events we seek to identify with screening. Moreover, even if we did have such studies, we would need to use our good judgment to decide how the trials’ results would apply to our patient population. For example, screening for tuberculosis (TB) might depend heavily on how prevalent TB is in the patients for whom we care. The low TB rate in the United States is comforting and may support doing little TB testing in many, but not necessarily all, US areas.
Dr Elman gives a lot of very reasonable advice, arguing that we have been doing too much testing. I may do even less than he does, not checking blood counts or blood chemistries for patients on TNF inhibitors. Most commercial insurers’ policies seem to agree with his advice not to require TB testing for patients on biologic IL-17 and IL-23 inhibitors. I get by with screening for signs and symptoms, asking, “Have you been having a cough, fever, night sweats, or unexplained weight loss?” in my review of systems and documenting, “TB screening negative by symptoms” in my assessment. Commercial insurers have accepted that as sufficient. They probably realize that routine laboratory testing is costly and counterproductive for these patients. The US Food and Drug Administration seems to be on board with the idea that IL-23 drugs should not require TB testing and, as Dr Elman points out, our newest IL-23 blocker icotrokinra does not require baseline or ongoing laboratory monitoring.
Dr Elman notes some worrisome concerns about the low rate of vaccination among patients receiving biologics, and he recommends assessing vaccination status when initiating these medications. However, if assessing vaccination when initiating biologics is of value, it may be because all our patients might benefit from being up to date on vaccination, not just patients on biologics. My focus in this area is encouraging patients going on JAK and TYK2 inhibitors to get vaccinated for shingles.
It is comforting when we know exactly what treatments and monitoring are needed. But perhaps nearly all the time, we do not. Instead, we must rely on our good judgment. That is what people are trusting us to do.
