Evaluation of the hypertensive state in treated patients: selection of appropriate blood pressure measurements per visit to the community pharmacy

Objective To assess the agreement between repeated blood pressure (BP) measurements taken by community pharmacists during visits to the community pharmacy on four separate occasions, and to assess the agreement between the community pharmacy BP (CPBP) measurement method and ambulatory BP monitoring (ABPM) in order to determine the CPBP measurements from each visit needed to evaluate the hypertensive state of treated patients. Methods The study was a cross-sectional study of treated hypertensive patients aged older than 18 years from eight community pharmacies. BP was measured during four visits to the community pharmacy (three measurements per visit) and for 24 h using ABPM (ABPM started on the third visit to the pharmacy). The Lin correlation-concordance coefficient, the Bland-Altman method, and the kappa coefficient were used to assess the agreement between CPBP measurements from each visit. The kappa coefficient was used to assess the agreement between the CPBP measurement method and ABPM to establish the patient's hypertensive state. The average CPBP was calculated using four methods: (i) three measurements/four visits, (ii) two measurements/four visits, (iii) three measurements/three visits, and (iv) two measurements/three visits. Results One hundred and seventy-six treated hypertensive patients were included. Overall, the agreement between the second and third CPBP measurement at each visit was higher than the agreement between other paired measurements (first vs. third and first vs. second), for both systolic BP and diastolic BP. The agreement between the CPBP measurement method and ABPM was not statistically different when analyzed using all variations of the average CPBP calculation. Conclusion The agreement between repeated BP measurements taken by community pharmacists at each visit was greater between the second and the third measurements. In contrast, the agreement between the CPBP measurement method and ABPM did not improve when the first CPBP measurement that was taken at each visit was excluded. As a result, the three CPBP measurements taken at each visit to the pharmacy could be used to evaluate the hypertensive state of treated patients. Blood Press Monit 16:103-110 (C) 2011 Wolters Kluwer Health | Lippincott Williams & Wilkins.