Is My Medicine Working for Me?
Examining MS Treatment
One of the hardest questions I am asked by patients is whether or not their medication is working. Simply put, this question cannot be answered for any one person. The disease-modifying drugs in MS were designed to prevent bad things from happening, and they do this with varying levels of effectiveness. This is not unique to MS to be sure. Indeed, treatment of conditions such as high blood pressure and high cholesterol is meant primarily to prevent strokes and heart attacks. However, one unfortunate feature of this makes it impossible to know what negative events— if any—may have been prevented in any patient. So there is no way to know for certain whether a medication is working in any individual.
The clinical trials have told us convincingly that for large groups of patients, those who take the medications for MS do better than those who don’t. However, the only way to know for sure if a medication is working in any individual patient would be to clone them and have them lead two lives; one where they take no medicine, and one where they take the medicine. I have yet to do this for any of my patients.
Studies of MS prior the introduction of treatments show that approximately 15 percent of patients have “benign” MS, where they are able to lead fully functional lives with minimal to no disability. For these people, no medications are necessary. The problem is, we have no way to identify at the time of diagnosis which patients are destined to have benign disease.
For the majority of patients who continue to have relapses and disease progression, I have no doubt that most of them would be worse off without medications. However, I can never say for sure.
One weakness of the MS community is to define exactly what is meant by treatment failure. If a patient has one relapse per year while on treatment, does that mean the medication is working or not? Perhaps without the medication, the person would have had three relapses. It is impossible to say. Certainly, I know some doctors who would switch a patient’s medication to a more aggressive treatment if they had a relapse every year. While for other doctors this would be an acceptable rate of disease progression—or at least not a reason to expose a patient to a more aggressive and potentially riskier treatment. There is also no consensus about what to do with patients who feel well, but continue to have new lesions on their MRI.
Ultimately, whether a medication is “working” or not depends on the individual patient. It is uncertainties such as this, however, that make medicine—especially neurology—an art as much as a science.