Blood pressure measurements taken by patients are similar to home and ambulatory blood pressure measurements

Comparison of blood pressure measurements obtained in the home setting: analysis of the Health Measures at Home Study

BACKGROUND

Automated blood pressure (BP) devices have been used in the home for self-management purposes and are increasingly being used in population-based research. Although these devices are convenient and affordable and may be used by inexperienced lay personnel, the potential impact of an examiner's skill level on the results needs to be evaluated quantitatively. The aim of this study was to compare BP measurements obtained in a home setting by personnel with healthcare experience with those obtained by personnel without healthcare experience. In addition, the percent agreement in high blood pressure (HBP) classification between the home BP measurement by the field interviewer (FI) and measurements obtained in a standardized environment was examined.

METHODS

The Health Measures at Home Study was a pilot study carried out among 128 adult participants recruited from the National Health and Nutrition Examination Survey. The Health Measures at Home Study provided the opportunity to compare the BP values obtained with an automated device in a home setting by both experienced health technicians (HTs) with those obtained by FIs who had no healthcare experience. Differences between measurements obtained by the HT and measurements obtained by the FI were assessed using paired t-tests, Pearson's correlations, and Bland-Altman plots. Percent agreement and κ-statistics were used to assess agreement in HBP classification between examiners in the home. Measurements obtained by the FI were also compared with those obtained in the National Health and Nutrition Examination Survey mobile exam center (MEC) by a physician using percent agreement and κ-statistics.

RESULTS

There was a high correlation in both systolic blood pressure (SBP; r=0.903) and diastolic blood pressure (DBP; r=0.894) between measurements obtained by HTs and those obtained by FIs. The mean SBP and DBP obtained by the FIs (SBP, 119.0±14.4 mmHg; DBP, 71.9±9.8 mmHg) were significantly higher than the HT measurements (SBP, 117.0±12.7 mmHg; DBP, 69.9.9±9.2 mmHg). In the home, the FI classified 11.7% as having HBP, whereas the HT classified 7.0%. The percent of individuals classified as having HBP by the physician in the MEC was 10.2% of the participants.

CONCLUSION

Operationally, FIs could take BP measurements in the home; however, there were some differences between measurements obtained by the FI and HT. The absolute difference between measurements obtained by the FI and those obtained by the HT in the home showed that measurements obtained by the FI tended to be higher than the HT, but the magnitude of these differences was less than 5 mmHg. The HT classified 7.0% of HBP whereas the FI classified 11.7% of HBP. Similarly, the FI and the MEC physician classified a different percent of individuals with HBP. Further investigation is warranted to determine the cause of these small but significant absolute differences between measurements obtained by the FI and HT.

[Nursing actions increases the control of hypertensive patients and reduces white-coat effect]

A randomized comparative study was performed to evaluate the control of hypertension with use of home blood pressure measurement (HBPM) and casual blood pressure measurement, and analyze the white coat effect. Hypertensive patients in primary health care units were randomly divided into two groups: group I, participating of the educational activities and group II that followed the routine treatment. The hypertensive patients from group I realized HBPM at the beginning and the end of the study. White-coat effect was evaluated by the difference between the casual blood pressure measurement and HBPM. The study included 290 hypertensive patients, but realized HBPM 82 hypertensive patients. There was increase in blood pressure control from the beginning to end of study in hypertensive patients from group I (p < 0.05) measured by HBP (60% to 68.3%) and casual measurement (62% to 71%) and in group II, HMBP hypertension control was higher than the casual blood pressure measurement (63% vs 50%). The white coat effect was greater in hipertensive patients from group II.

[Home blood pressure monitoring and control in a group of hypertensive patients]

This qualitative study was performed with 71 hypertensive patients, with the objectives to compare outpatient and home blood pressure monitoring (HBPM), to assess blood pressure control, and characterize white-coat hypertension. A nurse performed the outpatient blood pressure measurement. The home blood pressure monitoring was carried out over seven days. White-coat hypertension was quantified as a difference between the outpatient measurement and home blood pressure monitoring in the ranges from 1 to 5, 6 to 10 and > 10 mmHg. The outpatient blood pressure measurement was significantly higher (p<0.05) than the home blood pressure measurement. Pressure control corresponded to 9.9% in the outpatient measurement and 23.9% in the home blood pressure measurement. The white-coat effect > 10 mmHg was 57.7% for systolic and 32.4% for diastolic pressure, in the range from 6 to 10 mmHg. Home blood pressure measurement provided a better assessment of hypertensive patients' control.

[Home blood pressure monitoring: updates and the nurse's role]

This is a review article on home blood pressure monitoring (HBPM) developed with the purpose to increase the current scientific knowledge and present the importance of this approach in the care to patients with hypertension in our setting. This technique has advantages over the causal measurement, as it provides more measurements, a better relationship with the target-organs injuries, it also quantifies the white-coat effect, has good reproducibility, good acceptability by the patients, assesses blood pressure without the influence from the observer and the environment of the appointment, reduces the number of visits to the doctor and promotes greater adherence to treatment. The importance of nursing practice in HBPM is associated with the education process, using teaching-learning strategies, implementing team-patient communication and encouraging patients towards performing self-care.

Health-related quality of life and blood pressure control in hypertensive patients with and without complications

INTRODUCTION

The goal of antihypertensive treatment is to reduce blood pressure without interfering in health-related quality of life (HRQL) OBJECTIVE: This study aimed to assess the influence of hypertension control upon HRQL in hypertensive patients with and without complications.

MATERIALS AND METHODS

Seventy-seven hypertensive outpatients (71% women, 58% white, 60% with elementary school level education, average age 54 +/- 8 years) were observed during a 12-month special care program (phase 1: clinical visits every two months, donation of all antihypertensive medications, meetings with a multidisciplinary team, and active telephone calls) and three years of standard care (phase 2: clinical visits every four months, medication provided by the drugstore of the hospital with a two-hour wait and a possible lack of medication, no meetings with a multidisciplinary team or active telephone calls). The patient HRQL was assessed using Bulpitt and Fletcher's Specific Questionnaire, as well as the SF-36 scores. Hypertensive patients were divided into "with complications" (n=37, diastolic blood pressure great than 110 mm Hg for patients with or without treatment, with clinically evident target-organ or other associated illness) and "without complications" (n=40). The variables studied were quality of life, blood pressure control, hypertension gravity, and demographic characteristics.

RESULTS

In hypertensive patients with and without complications, both the systolic and diastolic blood pressure were significantly higher (p<0.05) in phase 2 of observation (143+/-18/84+/-11 and 144+/-21/93+/-11 mm Hg for patients with and without complications, respectively) relative to phase 1 (128+/-17/75+/-13 and 128+/-15/83+/-11 mm Hg). The proportion of patients with controlled blood pressure (defined as a blood pressure less than 140/90 mm Hg) decreased from 70% to 49% in the "with complications" group and from 78% to 50% in the "without complications" group during phase 2 of observation. The patients with complications showed a decrease in bodily pain, vitality, and mental health component summary scores in both phases. In phase 2, the patients without complications had significantly better HRQL scores compared to complicated patients using both the Bulpitt and Fletcher's Questionnaire and the SF-36 assessment of physical capacity, bodily pain, and vitality domain summary scores. With regards to hypertension control, there was a significant decrease from phase 1 to phase 2 in the vitality component summary scores and an increase in the emotional aspect component summary scores assessed by the SF-36, whereas Bulpitt and Fletcher's Questionnaire showed no differences in these scores.

CONCLUSION

Special care programs with multidisciplinary activities, individualized and personalized assistance, easy access to pharmacological treatment, frequent meetings, and active telephone calls for hypertensive patients significantly increase blood pressure control but do not interfere with the HRQL.