Pharmacy BP readings reduce ‘white coat’ hypertension
MedWire News: Blood pressure assessment in community pharmacy (CPBP) may overcome the problem of white coat hypertension sometimes encountered in the physician's office, research suggests.
In a study of 70 treated hypertensive patients, Spanish researchers have shown that CPBP measurement reliably confirm the presence of uncontrolled home blood pressure (HBP) whereas the specificity of physician office blood pressure (POBP) readings for this measurement is low.
Jose Sendra-Lillo (Community Pharmacist in Palmera, Valencia) and colleagues said that POBP measurement is limited by the 'white coat effect', where a patient's blood pressure increases in the presence of a healthcare professional or in an unfamiliar environment.
For the study, the team took three blood pressure readings from the participants at both the community pharmacy and the physician's office and four readings at the patient's home.
Using this data, they calculated the sensitivity, specificity, positive and negative likelihood ratios of CPBP and POBP measurements for detecting controlled and uncontrolled HBP.
CPBP had "acceptable-moderate" agreement with HBP measurements, with a sensitivity and specificity of 60.7% and 92.9%, and positive and negative predictive values of 8.5 and 0.4. Corresponding values for POBP were 75%, 54.8%, 1.7 and 0.5, respectively, the team reports in the American Journal of Hypertension.
Sendra-Lillo et al said: "The CPBP measurement was very reliable to confirm the presence of ucontrolled HBP because of its high specificity and positive predictive value.
However, they also point out: "Due to its low sensitivity and negative predictive value, the CPBP measurement method was not enough reliable to confirm the presence of controlled HBP, thus resulting in a high prevalence of masked hypertension."
Recognition of the value of CPBP measurement could be important because blood pressure measurement, which is traditionally performed in the physician's office, remains the cornerstone of hypertension management.
Overall, the researchers conclude: "The CPBP measurement method was superior to the POBP measurement method for detecting the presence of both uncontrolled and controlled HBP."
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By Josephine McCoan