Assessment of the diagnostic accuracy of home blood pressure monitoring by patients

Introduction: According to available guidelines, home blood pressure monitoring (HBPM) can be used to diagnose hypertension and monitor its treatment; however, its effectiveness has rarely been studied in developing countries, including Iran. Objectives: This study aimed to evaluate the diagnostic accuracy of HBPM, as compared with that of 24-hour ambulatory blood pressure monitoring (ABPM) and office blood pressure measurement (OBPM). Patients and Methods: This study was conducted on 28 patients suspected of having primary hypertension. The blood pressure of the patients was measured by four methods. Initially, blood pressure was measured by a non-physician using a digital sphygmomanometer in a clinic (OBPM-Digital). After about 1 hour, blood pressure was measured by a physician at the clinic using a mercury sphygmomanometer (OBPM-Mercury). In the third stage, the patient’s blood pressure was monitored for 24 hours by the ABPM method. In the fourth stage, each subject used a digital sphygmomanometer to measure HBPM for seven consecutive days. Results: The blood pressure values measured through the ABPM method were significantly lower than those measured by other methods (P<0.05). The prevalence of hypertension diagnosed by OBPM-Mercury, OBPM-Digital, HBPM, and ABPM method was 82%, 54%, 50%, and 21%, respectively. As compared with ABPM as the gold standard, the diagnostic accuracy of HBPM, OBPM-Digital, and OBPM-Mercury was 64%, 61%, and 32%, respectively. The frequency of white coat hypertension (WCH) diagnosed by HBPM and ABPM methods was 39% and 64%, respectively, and the frequency of masked hypertension (MH) diagnosed was 7% and 4%, respectively. The sensitivity, specificity, and diagnostic accuracy of HBPM, as compared with ABPM, in detecting MH were 100%, 96%, and 97%, respectively; in addition, as compared with WCH, they were 56%, 90%, and 68%, respectively. Conclusion: The findings of the present study showed that HBPM had higher diagnostic accuracy than OBPM in diagnosing hypertension. Also, HBPM was able to detect MH with a high level of diagnostic accuracy, and in more than two-thirds of cases, it was also able to detect WCH and diagnose patients with sustained hypertension.