Therapeutic Inertia and Measurement Inertia in Hypertension: A Call to Action

In this issue of The Journal of Clinical Hypertension, Desai and colleagues1 discuss the prevalence of therapeutic inertia regarding blood pressure (BP) control in a select population of hypertensive chronic kidney disease (CKD) patients at a single site in an academic institution. In this study of a higher-risk population, which utilizes retrospective chart view, several key points warrant commentary. The authors rightly first used the broad, commonly used definition of clinical inertia as the failure to institute a change in therapy based on BP measurement not at goal. Their finding, that the prevalence of therapeutic inertia closely mimics that seen in the National Health and Nutrition Examination Survey (NHANES) in a general population, warrants concern, especially since this higher-risk group was followed in a specialty clinic at an academic center. The authors then more narrowly define true therapeutic inertia as excluding several key populations. These are all reasonable modifications to the term therapeutic inertia and add greater precision to the term. These adjustments remove those patients from a category in which they do not belong. Accepting this updated definition will allow a better grasp as to what is the true prevalence of therapeutic inertia. Importantly, with the increasing focus on home and other out-of-the office BP readings, it is consistent with care to base treatment decisions on those readings when available and trusted. Therapeutic inertia aside, the most troubling revelation of this honest chart review is the observation that decisions for hypertension management were far more often than not based on single BP readings. The authors deserve credit for the transparency of their methods. The lack of consistent evidence that repeat BP measurements were performed during the visits of these patients with hypertension and CKD, seen by nephrologists in an academic center, is disconcerting and represents a different type of inertia—that of measurement inertia. There exists the possibility that additional BPs were measured and not recorded, but the absence of repeat BP in the charts would suggest that this effort was done in only a minority of patients. This is troubling on many levels. The care of patients is compromised by directing therapeutic decisions based on single readings. The education of students and residents is compromised by the example served by basing decisions on single readings. It suggests that far greater efforts need to be expended to raise awareness and to educate both providers and patients as to the need for multiple BP readings at each visit for every hypertensive and prehypertensive patient, and to do otherwise represents a creeping inertia towards measurement. The recognition that a single reading would not suffice for decision-making was noted more than 100 years ago by Dr Riva-Ricci. This pioneer advised that one need to consider ≥5 readings because of the wide variability seen in BP readings. It is recognized that a single reading correlates less well with outcomes than multiple readings.2 The American Heart Association as well as the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC 7) guidelines state that at least 2 BP readings be recorded. Often the first obtained reading is the highest. Furthermore, as is often the case, a difference >5 mm Hg requires an additional 1 or 2 measurements be recorded as well.3, 4 This retrospective chart review study demonstrated what is undoubtedly all-too-common: single BP recordings that guide treatment in the management of hypertension. If one moves to the more public and easily observed areas of the hospital, skilled nursing centers, and public screenings, one finds that casual observation of BP measurement performed there fares little better with single readings the norm, regardless of the reading. So how did this come to pass? How did this inertia for measurement develop? Were BP measurements ever performed properly? Since cautions regarding the need for multiple readings reach back decades, it would appear that this has been a challenge since the advent of measuring and recording BP. Perhaps along the way, we as caregivers got sloppy. When BPs were markedly elevated, as in a single reading in the 200s, it was clear that the patient warranted treatment. Confirmation was deemed not necessary and redundant. Perhaps as BP moved away from the mystique of medicine (back to JNC I) it became viewed as something so simple anyone could do it—and anyone can do it—poorly and incorrectly? Perhaps the development and marketing of effective and well-tolerated medications allowed the bad habits to continue, easy to prescribe and easy for the patients to tolerate? Regardless as to what happened along the way, we have failed to demand the same precision in our measurement of BP as we do from our smart phones. Even clinical studies were not immune to the creep of measurement inertia (single readings), ie, the Heart Outcomes Prevention Evaluation (HOPE), thereby greatly limiting the value of data that could be gleaned from this study. I believe that we need a major education effort that should be multifaceted and multilayered. First, these efforts should be geared toward health care providers, primary as well as specialty care. Anyone who takes a BP measurement needs to get it right. The American Society of Hypertension (ASH) should make this the keystone of improving the care of hypertensive patients. ASH should assume leadership in this matter and enlist the aid of other professional societies for physicians, nurses, physician assistants, and nurse practitioners in spreading the word. This should be a priority for all and perhaps the timing with JNC 8 would be an ideal time. Second, educate the public. Inform them as to proper technique of BP measurement. BP measurement inertia and therapeutic inertia, issues separate and distinct, are both linked to improper care of the hypertensive patient. Until we place greater efforts into improving both, we fail, for without marked improvement in these areas, attaining our goal of controlled BP in our communities is as elusive as a wisp in the willow.