White coat hypertension prevalent in people with elevated clinic BP

More than half of individuals with elevated clinic blood pressure (BP) attending a primary care clinic in Singapore have either white coat hypertension (WCH) or undiagnosed hypertension, reports a study.

The finding highlights the need for primary care physicians to promote home BP self-monitoring and adopt standardized guideline-based methods for home BP interpretation, according to the researchers.

This feasibility study recruited 60 individuals (mean age 61.8 years), of whom the majority were Chinese (90 percent) and married (63 percent). More than half of them had hyperlipidemia, with 56.7 percent overweight or obese. [Proc Singap Healthc 2025;doi:10.1177/20101058251350732]

Nearly one in four participants (23.3 percent) had a WCH diagnosis, while 35 percent were newly diagnosed with hypertension. None of those with WCH reported having significant anxiety as assessed by the GAD-7 scale.

"Our study, conducted among individuals without any known psychiatric conditions, found no difference in anxiety levels between individuals with WCH and those without,” the researchers said. “This finding aligns with prior research finding no association between general anxiety traits and WCH.” [J Hypertens 1997;15:585-590]

Another study focusing on context-specific anxiety suggested that a patient’s expectation of high BP or stress during the visit can result in a temporary elevation in BP. [Blood Press Monit 2005;10:317-319]

“These findings suggest that WCH may be more closely linked to context-specific anxiety surrounding the clinic visit rather than general anxiety traits,” the researchers said. “Recognition of this finding could guide interventions targeted at reducing patient stress during visits to optimize diagnostic precision.”

Eyeball method

Additionally, compared with the 2018 ESH/ESC method, the clinician “eyeball method” in the current study identified five (12 percent) more individuals being newly diagnosed with hypertension.

“The clinician ‘eyeball method’ could result in an overdiagnosis of hypertension and unnecessary pharmacological treatment,” the researchers said. “It should be replaced by guideline-backed practices.”

Such method involves a visual scan of BP readings by a clinician to determine the presence of elevated readings. [Circulation 2020;142:e42-e63; Front Med 2024;11:1343387]

Although the method is imprecise, many physicians continue to apply this practice because of time constraints in consultations and the use of handwritten BP records, which make the calculation of mean readings difficult. [J Prim Care Community Health 2024;15:21501319241291466]

"Physicians should be reminded to adopt guideline-based practices and advocate for digital home BP recording to ensure the fidelity of readings and simplify interpretation,” the researchers said. “Additionally, digital solutions that automate the conversion and interpretation of handwritten BP records would enable appropriate care for patients who cannot use digital tools.”

The current study was conducted between November 2019 and October 2023 among individuals with elevated clinic BP at a primary care clinic in Singapore. The researchers obtained data across two visits through an interviewer-administered questionnaire and a weeklong self-measured BP monitoring program.

Three methods were used to interpret the home BP readings: average of all readings, 2018 ESH/ESC guidelines, and clinician eyeball method.

“Future studies should focus on simplifying the integration of these evidence-based practices into daily primary care practice, thereby enhancing diagnostic accuracy and ensuring appropriate treatment for patients,” the researchers said.