May 20, 2021, 12:25 p.m. Michael Devitt — On April 27, the U.S. Preventive Services Task force issued a final recommendation statement, final evidence review and evidence summary on screening for hypertension in adults.
Based on its review of the evidence, the task force recommended screening for hypertension in adults 18 years or older with office blood pressure measurement, and also recommended obtaining blood pressure measurements outside of the clinical setting for diagnostic confirmation of hypertension before starting treatment. This is an “A” recommendation, meaning that the USPSTF has concluded with high certainty that screening for hypertension in adults has substantial net benefit, and it applies to all adults 18 years or older without known hypertension.
“Without screening, most people wouldn’t know they have hypertension and could be at risk for a heart attack or stroke, said John Wong, M.D., a member of the task force, in a press release. “Clinicians can improve their patients’ health by screening all adults for hypertension.”
Hypertension is the most common primary diagnosis in the United States and affects about 45% of all American adults, with the prevalence higher in men and in individuals 40 and older. It is a major contributing risk factor for heart failure, myocardial infarction, stroke and chronic kidney disease. Factors that can increase a person’s risk for hypertension include older age, Black race, family history, excess weight and obesity, lack of physical activity, tobacco use, and a diet that is high in fat or sodium.
The final recommendation is consistent with and reaffirms the task force’s 2015 recommendation on the topic, which also recommended screening for hypertension in adults 18 or older and recommended obtaining measurements outside of the clinical setting to confirm a diagnosis. The Academy supported the 2015 recommendation statement.
To update the 2015 recommendation, the task force commissioned an evidence review to evaluate the benefits and harms of screening, the accuracy of OBPM for initial screening, and the accuracy of other measurements such as ambulatory or home blood pressure monitoring.
The evidence review consisted of a re-evaluation of all studies included in the task force’s previous review, along with a literature search of studies published between February 2014 and August 2019. Searches were supplemented by examining study bibliographies, consulting outside experts and reviewing results from ongoing and/or unpublished trials.
The task force reviewed evidence from 20 studies on the accuracy of OBPM for initial screening for hypertension; in all studies, blood pressure was measured at the brachial artery and ambulatory blood pressure monitoring was used as the reference standard. Compared with ABPM references, the researchers found that screening administered at a single visit has low sensitivity and adequate specificity.
The task force also reviewed evidence from 18 studies on the accuracy of other methods to evaluate adults who initially screened positive for hypertension via OBPM, again with blood pressure measured at the brachial artery and ABPM used as the reference standard in all studies. Compared with ABPM references, confirmatory OBPM or home blood pressure monitoring — applied to a preselected patient population — was found to be generally more sensitive, but not as specific.
No studies on unattended automated office blood pressure monitoring or kiosk blood pressure measurements to screen or confirm hypertension met inclusion criteria; as a result, these methods were not included in the review.
With regard to benefits and harms, the researchers found no trials that compared the effectiveness of screening for hypertension versus no screening. However, results of a community-based, cluster randomized clinical trial of adults 65 or older found that providing pharmacy-based blood pressure screening and a cardiovascular disease risk assessment resulted in a 9% reduction in the number of hospital admissions for acute myocardial infarction, congestive heart failure or stroke at one year of followup. The task force also determined, based on a review of 13 studies, that the harms of screening for hypertension are minimal, with the most likely harm being a misdiagnosis resulting in under- or overtreatment.
The task force also noted that while there is a well-documented association between masked hypertension (i.e., blood pressure measurements that are high when obtained outside the office but normal in clinical office settings) and white coat hypertension (i.e., measurements that are high when obtained in a clinical office setting but normal when obtained outside the office), and increased cardiovascular risk, more evidence needs to be conducted to determine whether early detection and treatment of these types of hypertension lead to an improvement in patient health.
A draft version of the recommendation statement was posted for public comment on the USPSTF website from June 23, 2020, through July 20, 2020.
In response to questions from commenters about specific techniques to accurately measure blood pressure, the task force included a brief description of how blood pressure was measured in studies to the Practice Considerations section, and added language clarifying that the blood pressure measurements were taken at the brachial artery.
The task force also provided resources from the CDC and the Community Preventive Services Task Force on how to accurately measure blood pressure in the recommendation’s Additional Tools and Resources section of the recommendation, and information on validated blood pressure measurement devices from other organizations in the Recommendations of Others section.
Some commenters expressed concern that patients may face certain barriers or burdens in trying to measure their blood pressure outside of a clinic setting. In response, the task force provided resources from several organizations in the Additional Tools and Resources setting.
Finally, in response to recommendations from several commenters that annual screening for hypertension be added to annual wellness visits for patients between the ages of 18 and 40, the task force stated that the available evidence on optimal screening intervals for hypertension remains limited, and that the intervals described in the Practice Considerations section of the recommendation were based on the best available data.
“Screening adults for hypertension in the office and corroborating with out-of-office blood pressure readings can help correctly identify patients with hypertension,” Alexis “Alex” Vosooney, M.D., of West St. Paul, Minn., a member of the Academy’s Commission on Health of the Public and Science, told AAFP News in response to the recommendation. She added, “Using out-of-office readings is an appropriate measure for family physicians to look at when considering a diagnosis.”
While Vosooney has not encountered a patient who was opposed to screening, she mentioned having several patients who said they felt that just being in the clinic resulted in elevated blood pressure measurements. She said that talking to those patients about out-of-office measurements not only helped to identify individuals with hypertension, but also raised patients’ awareness that their blood pressure levels could also be elevated in situations they considered less stressful than a clinic visit.
“That awareness helped with patient buy-in when discussing the need for lifestyle changes and medication,” said Vosooney.
Although measuring blood pressure at home could identify more patients with hypertension, Vosooney said that the cost of a home blood pressure monitor could present financial challenges for some patients. To resolve the issue, Vosooney suggested that family physicians check for state or local programs that may offer low-cost blood pressure monitors for patients. Alternatively, patients may be encouraged to see if their health insurance includes coverage for purchasing a home blood pressure monitor or ambulatory blood pressure monitoring.
The AAFP’s Commission on Health of the Public and Science plans to review the task force’s final recommendation statement, final evidence summary and evidence review, and will then determine the Academy’s stance on the recommendation.