Validez de la medida aislada de la presión arterial en farmacia comunitaria. Puntos de corte óptimos

Abstract

Introduction and objectivesThe aim of this study is to determine the diagnostic validity of blood pressure measurement in the community pharmacy (CPBP), and to set the cut-off points in systolic blood pressure (SBP) and diastolic blood pressure (DBP) in order to maximise the aforementioned validity, using 24 hour ambulatory blood pressure monitoring (ABPM) as the reference method. Material and methodsA cross-sectional study with consecutive selection of patient users of the community pharmacy in Andalusia. The CPBP was measured, followed by 24-hour ABPM, which assessed the diagnostic validity of the CPBP. The AUC of the ROC curve was also calculated for SBP and DBP, along with the positive and negative predictive values, for different prevalences and the variation of sensitivity and specificity for the different cut-off points for SBP/DBP. ResultsA total of 167 community pharmacy participated with 1,170 patients, of which 1,110 were valid. The CPBP showed a sensitivity of 60.41% (95% CI: 56.40-64.29), and a specificity of the 79.77% (95% CI: 76.12-82.99), a positive predictive values of 76.96% (95% CI: 72.89-80.57), and a negative predictive values of 64.31% (95% CI: 60.55%-67.90%). By using the ROC curve method, the optimal cut-off points are 134/81mm Hg, the point where the sensitivity and specificity and are balanced and the Youden index is maximised. ConclusionsThe sensitivity is relatively low. To improve it tends to lower the cut-off points of SBP and DBP. The calculated optimum is 134/81mm Hg. This provides data on the desirability to review the current cut-off points (140/90), as proposed by the ACC/AHA 2017.