Hypertension performance measure ‘flawed’

Even though it's critical for internists to monitor patients for hypertension, the Controlling High Blood Pressure performance measure used in several federal programs is far from ideal, according to ACP's Performance Measurement Committee (PMC).

The measure, which is designated as Quality ID #236 (NQF 0018), is currently defined as the percentage of adults ages 18 to 85 years who had a diagnosis of hypertension and whose blood pressure was adequately controlled (<140/90 mm Hg) during the measurement year. While the PMC considers the measure to be “high impact,” it determined after review in July 2021 that it does not support the measure due to uncertain validity.

The PMC took issue with the measure's requirement for strict blood pressure control across the whole patient population. The committee also noted that the measure deviates from actual practice by assessing the most recent blood pressure from the measurement period, among other concerns.

One area of concern is the target blood pressure below 140 mm Hg. Although there are benefits associated with that range, the risk of harms increases with age. Elderly patients are also likely to be frail, to have multiple chronic conditions, and to be taking multiple medications. ACP's 2017 guideline on pharmacologic management of hypertension strongly recommends a systolic blood pressure below 150 mm Hg in adults older than 60 years of age and intensifying treatment to achieve a blood pressure below 140 mm Hg only in patients older than age 60 years who have a history of stroke or transient ischemic attack or high cardiovascular risk.

ACP Internist recently discussed the committee's review of the measure with Peter Basch, MD, MACP, a member of the PMC, a Fellow of the Royal College of Physicians (London), and senior director for IT quality and safety, research, and national health IT policy at MedStar Health in Washington, D.C.

Q: What is the importance of this measure, and why is it considered to be “high impact”?

A: Hypertension is a very common chronic condition, and controlling hypertension is known to reduce the long-term sequelae, such as heart attack, stroke, and kidney failure. The PMC appreciates the significance of controlling hypertension and that there is almost certainly a performance gap. These two facts mean that a measure for controlling hypertension is needed and that if the measure is a good measure, it could help patients and clinicians to improve blood pressure control.

Q: What are the PMC's concerns about the measure?

A: While this measure has improved over the last few years, the PMC still sees it as flawed. Our concerns include the following:

The measure's approach to determining blood pressure control is outdated. The measure is still based on what was feasible years ago, when chart abstractors had to read paper records and enter blood pressure values into a report—meaning only the last blood pressure taken during the measure period (typically a calendar year) determines whether the patient was under control throughout the year. This can cut both ways: A patient could have high blood pressure all year, and on Dec. 31, a single reading might be <140/<90—and this patient is considered “controlled” and thus meets the measure. Conversely, a patient can be well controlled throughout the year, and a single reading on Dec. 31 of 140/70, for example, changes this patient to “uncontrolled.” As most doctors have been using EHRs for over a decade, most blood pressures are captured digitally; thus, other, more robust approaches to blood pressure control determination (such as a mean blood pressure, time under control, etc.) would make the measure more meaningful.

The method for documenting appropriate exclusions is fragile. The measure has been enhanced to exclude circumstances that shouldn't be included in the measure, such as frailty, not taking blood pressure the day of a procedure, being in end-of-life care, etc. The problem: How these are captured is highly dependent on documentation and data mapping—which may be unknown to the clinician or, if known, so apart from normal workflow that appropriate exclusions are unlikely to be reliably captured.

Home blood pressure readings may count toward the measure—but only under some circumstances, which may be opaque to the doctor. While home blood pressure readings are permitted under specified (and reasonable) circumstances, these readings will only count toward the measure if entered in the context of a “qualifying encounter.” This is a terrific step forward, as far as it goes. Thus, home readings may count when documented during an office visit, telehealth visit, or phone visit—the key here being the context of the visit code. However, certain workflows typically not associated with a qualifying visit code (such as patients reporting home readings as a phone message, portal message, or via remote patient monitoring) may appear in your EHR but won't count in the measure.

All outpatient blood pressures taken during qualifying outpatient encounters count toward blood pressure control. Except for the exclusions mentioned above, this measure does not recognize the difference between blood pressure as a reading to establish control and blood pressure as a vital sign. Consider how we approach blood pressure measurement in these two circumstances: a patient coming in for a blood pressure follow-up and a patient seen for an acute illness or injury. In the first instance, we would want to know that the patient took their normal medications that day and that they were not sick, in pain, anxious, etc. And the technique for obtaining the blood pressure must be followed: Patient is sitting, both feet on the floor, measurement arm is supported at the level of the heart. If the first reading was elevated, the blood pressure would likely be repeated at least once. For patients with a validated home monitor, we might also ask for recent, high, low, and median/typical readings—after all, we may add or change a medication based on readings that we believe to be an accurate representation of the patient's blood pressure. This is not the case when we simply obtain a blood pressure when a patient is sick or in pain. This can be even more of a problem in multispecialty groups, where the internist's carefully managed “blood pressure control readings” are overridden by “blood pressure as vital signs” taken when the patient was acutely ill or in pain.

Q: What are the implications of these concerns?

A: If doctors are going to take performance measurement seriously, they must find the scores believable and actionable. With the actual (or potential) points of failure mentioned above, internists are not wrong to be concerned that a mediocre score is just as likely to be due to measure problems [as] an accurate determination of blood pressure control. And when that message is associated with a measure, clinicians will either ignore suboptimal scores or, even worse, cynically address remediation as treating the data rather than treating the patient.

Q: What are the next steps for this measure?

A: Fortunately, the PMC's feedback on performance measures is taken seriously by measure stewards and measure users. More importantly, our recommendations on this measure and others will help College membership to use evidence-based measures that do lead to improving care and clinical outcomes of our patients. Most measures have annual updates, but it will likely take several years for this measure to see substantial updates.

Q: What are your main takeaways for internists using this measure?

A: While my comments were focused on why the PMC did not support this measure, for some internists this measure can be used successfully in its current state. Here are some recommendations for using the Controlling High Blood Pressure measure if you are required to use it or if you think it's a good fit for your practice:

• Don't assume you know how you are being scored and when. Familiarize yourself with the measure specifications, such as when entering a blood pressure counts toward the measure and when the measure ignores a reading.
• Ask your EHR vendor how exclusions were mapped within the EHR, and then validate what you've been told on a few patients.
• Also ask your EHR vendor how you should document home blood pressures that are reported outside of traditional office visits.
• Ideally, develop (or continue) workflows for yourself and your clinical staff where blood pressure is measured whenever possible. Make it a standard practice to repeat elevated readings.
• Remember, a blood pressure of 140/90 is considered out of control. So is a blood pressure of 140/60 or 120/90. While as clinicians we appreciate that borderline elevated readings are likely fine, to the performance measure, a blood pressure of 140/90 counts as “unmet” as much as a blood pressure of 180/100.
• When a patient's blood pressure is artifactually elevated during an office visit (due to pain or acute illness), if the patient has a validated home monitoring cuff and you trust the patient is able to use it correctly, have a consistent workflow for getting one or more repeat readings when the patient's circumstances change.
• Lastly, this measure is less problematic when all clinicians in your EHR domain are within specialties that manage blood pressure and understand the nuances of its associated performance measure.