Regular Use of a Home Blood Pressure Monitor by Hypertensive Adults—HealthStyles, 2005 and 2008

Abstract

J Clin Hypertens (Greenwich). 2012;14:172–177. ©2012 Wiley Periodicals, Inc.

The authors analyzed HealthStyles surveys 2005 and 2008 combined to assess the prevalence of regular home blood pressure monitor (HBPM) use among hypertensive adults. All data were self‐reported. The authors calculated odds ratios (ORs) of regular HBPM use and relative percent change (RPC) in the use of HBPM between the 2 survey years. There were 3739 (32.6%) hypertensives in the 2 survey years combined. Based on the self‐reported data, the proportion of hypertensives who regularly used an HBPM was 43.2%. Male sex, age, race/ethnicity, household income, and education were all associated with differences in the prevalence of regular HBPM use. Patients 65 years and older (OR, 2.38; 95% confidence interval [CI], 1.49–3.81) were significantly more likely to be regular HBPM users than those 18 to 34 years. Non‐Hispanic blacks were significantly less likely (OR, 0.69; 95% CI, 0.55–0.86) to be regular HBPM users than non‐Hispanic whites. From 2005 to 2008, the RPC in regular HBPM use was 14.2% (from 40.1% to 45.8%); the largest RPCs were for the 3 youngest age groups, men, non‐Hispanic blacks, and those with a household income of $40,000 to 59,900. Because HBPM has been demonstrated to aid in hypertension control, health care professionals should promote its use especially among hypertensives who are younger, non‐Hispanic blacks, Hispanics, or with a lower income.

Although the control of hypertension in the United States has improved during the past 2 decades, ¹ , ² , ³ a report using 2005–2008 national data estimated that just 45.8% of hypertensive adults in the United States had their blood pressure (BP) under control. ² A separate report focusing on disparities in hypertension control and using different methods found the age‐standardized prevalence of control to range from 36.9% to 47.7% among racial/ethnic groups in the United States. ³ This unsatisfactory record is particularly disappointing in light of the improvements and availability of home BP monitors (HBPM) over the past 2 decades. ⁴ Hypertension is a major risk for heart disease, stroke, end‐stage renal disease, and peripheral vascular disease; its control can help reduce these serious sequelae. ⁴ , ⁵ , ⁶ Thus, improving hypertension control should continue to be a major public health priority.

Prior to the 1990s, the management of hypertension depended solely on the tracking of BP measurements by health care professionals. This was combined with evidence‐based lifestyle modifications and/or antihypertensives. Since becoming less expensive, more reliable, and validated, electronic BP devices are increasingly more popular in hospitals and clinics and for personal use. Portable HBPMs have improved access to home monitoring and made it possible for many patients to measure and track their BP. ⁴

Since the release in 1997 of the Sixth Report of the Joint National Committee for Prevention, Detection, Evaluation and Treatment of High Blood Pressure (JNC 6) ⁷ with its recommendations for using electronic HBPMs to manage hypertension, multiple clinical trials have demonstrated the usefulness of these devices in assisting patients and their physicians in improving control of BP. ⁸ , ⁹ , ¹⁰ , ¹¹ , ¹² , ¹³ , ¹⁴ , ¹⁵ , ¹⁶ , ¹⁷ , ¹⁸ For example, meta‐analysis of clinical trials showed that HBPM monitoring led to 2‐fold greater reduction in medication (relative risk, 2.02; 95% confidence interval [CI], 1.32–3.11) compared with clinical BP monitoring. ⁸ HBPM use has been shown to improve adherence to medication to allow for down‐titration and stabilization of BP control as well as to be superior to clinic BP measurements for white‐coat effect, predicting cardiovascular prognosis and end‐stage renal disease. ⁸ The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (JNC 7), ⁶ released in 2003, maintained a recommendation of the routine use of validated non‐mercury HBPMs. ⁶ , ¹⁹ United States Preventive Services Task Force (USPSTF) ¹⁷ report included evidence that self‐monitoring of BP not only identified hypertensive adults at increased risk for cardiovascular disease (CVD) but also helped in the treatment of high BP, which could substantially decrease their risk for serious sequelae. Importantly, the USPSTF report indicated that BP measurements had negligible harmful effects.

Subsequently, in 2008, the American Heart Association, American Society of Hypertension, and the Preventive Cardiovascular Nurses Association jointly released a call to action that promoted the use of HBPMs and their reimbursement by insurance companies and other third‐party health care payors for all hypertensive adults. ²⁰ More recently, the role of HBPMs has been shown to significantly improve hypertension control especially when combined with special clinic‐based programs involving antihypertensive titration ⁸ or with telemonitoring. ⁸ , ²¹ In addition, HBPMs are employed by community health workers and promotores de salud ²² , ²³ , ²⁴ as adjuncts for monitoring BP.

The use of efficient strategies to monitor and reduce BP among hypertensives was critical for achieving the target of 50% set forth in Healthy People 2010 objective 12.10 “Increase the proportion of adults with high BP who have it under control.” ²⁵ In the newly launched Healthy People 2020, the relevant target has been raised to 61.2%. ²⁶ Regular HBPM use has been shown to be effective and should be integrated into hypertension management protocols to improve hypertension control. ²⁰

Although a variety of validated HBPMs are available and there is ample evidence to support the benefit of their use in improving hypertension control, there is still a lack of information on the actual use of HBPMs among hypertension adults in the United States. Accordingly, we used self‐reported data from the 2005 and 2008 HealthStyles surveys to assess (1) the associations between the proportion of hypertensive adults who regularly used HBPMs and selected sociodemographic characteristics, (2) the association between the frequency of regular HBPM use and the perception that it helped control their BP, and (3) the relative percentage change (RPC) from 2005 to 2008 in the proportion of hypertensive adults who regularly used HBPMs.

Methods

The HealthStyles survey is an annual questionnaire mailed to US adults 18 years and older and administered and managed by the public relations firm Porter Novelli (New York, NY) with technical assistance from the Centers for Disease Control and Prevention (CDC). ²⁷ Households were invited to participate in the consumer opinion panel through a recruitment survey. The list of households was randomly obtained from a large credit‐report agency. Approximately 450,000 households in 2005 and 340,000 in 2008 agreed to complete the mail survey. In return for their participation, respondents were given a small monetary incentive (coupon totaling <$5) and were entered into a random drawing for a first‐place prize of $1000 and 20 second‐place prizes of $50. Subsequently, there were two additional phases of mailed surveys: (1) ConsumerStyles and (2) HealthStyles. First a list of 20,000 households in 2005 and 20,000 in 2008 was selected to participate according to region and its population density, household income, age, and household size to create a nationally representative sample. A low‐income and a minority supplementary sample was used to ensure adequate representation of these groups. A total of 12,639 households in 2005 and 10,108 in 2008 completed the ConsumerStyles survey, yielding a response rate of 63.0% in 2005 and 50.6% in 2008. The list of ConsumerStyles respondents was used for the second‐phase survey mailings (HealthStyles).

The HealthStyles questionnaire was sent to 6168 households in 2005 and 7000 in 2008 that responded to the ConsumerStyles survey. Responses were received from 4819 (78%) participants in 2005 and 5399 (77%) in 2008. No information was available for nonresponders. The survey was designed to collect data about health beliefs, attitudes, social norms, and behaviors including HBPM use to monitor one’s BP and actions taken to modify lifestyle or the taking of antihypertensives to control BP. The individual participants included in each study sample from HealthStyles surveys 2005 and 2008 were weighted for age, sex, race, income, and household size to represent the US 2000 Census population.

Definition of the Study Measurements

Respondents were classified as having hypertension if they answered “yes” to the question “Have you ever been told on two or more different doctor visits that you had high BP?” and if a female respondent did not answer “yes” to the question “Was this only during pregnancy?” Respondents were also classified as hypertensive if they answered “yes” to the question “Has a doctor ever prescribed medication to help lower your BP?” We excluded the 152 responding adults in 2005 and their 129 counterparts in 2008 with only pregnancy‐related hypertension. Of the 10,218 adults 18 years and older who participated in survey years 2005 or 2008, we estimated that 3739 (32.6%) were hypertensive.

The classification of regular use of HBPM required answering “yes” to the question “Do you or other members of your household have a machine, device, or instrument to measure BP at home?” and checking “Yes, I use it to check my BP” or “Yes, someone else uses it to check my BP” on the question “Do you or other members of your household use this machine or device?” In addition, to be defined as regular users, respondents had to check “Once a day,”“Once a week,” or “Once a month” for the question “How often is this device used to check your BP at home?” The perception of whether regular HBPM use helped to control BP was determined by a positive response to the question “Has checking your own BP or having it checked at home helped you control your BP?”

Statistical Analysis

Frequency analyses provided information on the percentage of persons with hypertension who regularly used an HBPM by sex, age (18–34, 35–44, 45–64, and ≥65 years), race/ethnicity (non‐Hispanic white, non‐Hispanic black, Hispanic, non‐Hispanic other), household income in thousands of dollars (<25, 25–39.9, 40–59.9, and ≥60), and education (less than high school graduate, high school graduate, some college, and college graduate or more). The χ² test was performed to test differences in HBPM use, with an α level of 0.05 considered significant. An RPC was calculated to assess changes in the use of HBPMs between 2005 and 2008. To ensure a robust analysis, multiple logistic regression analyses were conducted on the combined data years to examine the associations between regular HBPM use and select characteristics independently. Adjusted odds ratios (AORs) along with 95% CIs were obtained for each model after controlling for age, sex, race/ethnicity, household income, and education level. All statistical analyses were performed with the statistical software package SAS, version 9.2 (Cary, NC).

Results

Among the 3739 hypertensive adults included in the 2005 and 2008 surveys, there were 42.5% non‐Hispanic blacks, followed by 32.8% non‐Hispanic whites, 26.7% non‐Hispanic other, and 25.4% Hispanics (Table). Adults with the lowest level of household income (<$25,000) had the highest estimated prevalence of hypertension (38.5%), and those in either of the 2 lowest education levels (less than high school graduate and high school graduate) had a higher prevalence than those with some college education and college graduates. The estimated prevalence of regular HBPM use among all hypertensive adults was 43.2% and was higher in men than women. Hypertensive adults aged 45 to 64 or 65 years or older had a higher prevalence of regular use than those aged 18 to 34 or 34 to 45 years (P<.0001). The non‐Hispanic other group had the highest prevalence of regular HBPM use (48.2%), followed by non‐Hispanic whites (45.9%), Hispanics (37.0%), and non‐Hispanic blacks (33.1%; P<.0001). The prevalence of regular HBPM use was greatest in the 2 highest income groups and differed significantly from usage rates in the bottom 2 income groups (P<.0001). In addition, the prevalence of regular HBPM use was greater with each successive education level, although not statistically significant. Finally, significantly more hypertensive adults who made daily (86.3%) or weekly (82.3%) use of an HBPM perceived that its use helped control their BP in a comparison with those using an HBPM only monthly (69.9%; P<.0001) (Figure 1).

Table TABLE.

 Prevalence^a of Self‐Reported Hypertension and Regular Use of an HBPM^b Among Hypertensive Adults by Select Characteristics—HealthStyles Surveys, 2005 and 2008 (combined)

Characteristic	Total No.	Hypertensive Adults
		Proportion With Hypertension		Regular HBPM Use		P Valuec
		No.	% (95% CI)b	No.	% (95% CI)
Overall	10,218	3739	32.6 (31.4–33.7)	1601	43.2 (41.3–45.2)
Age, y
18–34	1546	238	13.5 (11.2–15.7)	55	33.2 (23.6–42.7)	<.0001
35–44	2414	488	20.4 (18.6–22.2)	149	30.5 (26.0–35.0)
45–64	4519	1917	43.5 (41.9–45.0)	814	43.3 (40.9–45.7)
65+	1739	1096	61.9 (59.4–64.4)	583	52.5 (49.3–55.7)
Sex
Men	4571	1771	34.4 (32.6–36.1)	815	45.2 (42.4–48.0)	.04
Women	5647	1968	30.9 (29.4–32.4)	786	41.2 (38.4–43.9)
Race/ethnicity
Non‐Hispanic white	6925	2469	32.8 (31.4–34.2)	1125	45.9 (43.6–48.3)	<.0001
Non‐Hispanic black	1279	644	42.5 (38.8–46.2)	221	33.1 (29.1–37.2)
Hispanic	1300	403	25.4 (22.4–28.4)	149	37.0 (30.7–43.2)
Non‐Hispanic other	714	223	26.7 (22.6–30.8)	106	48.2 (40.1–56.3)
Household income, in thousands of dollars
<25	2780	1308	38.5 (36.0–41.0)	493	38.6 (35.3–41.8)	<.0001
25–39.9	1474	525	29.9 (26.9–32.8)	211	38.4 (33.8–43.1)
40–59.9	1691	562	30.4 (27.6–33.3)	255	45.4 (39.9–50.9)
>60	4273	1344	30.7 (29.1–32.4)	642	48.3 (45.1–51.5)
Education leveld
<HS graduate	703	312	37.0 (31.9–42.0)	118	38.3 (32.3–44.3)	.008
HS graduate	2544	1074	38.0 (35.7–40.3)	422	39.4 (36.2–42.6)
Some college	3645	1310	32.1 (30.1–34.0)	573	44.4 (41.1–47.8)
College graduate or more	3090	978	30.5 (28.4–32.6)	468	47.2 (43.3–51.2)

Abbreviations: CI, confidence interval; HS, high school. ^aPrevalences are weighted for age, sex, race, income, and household size to represent the US 2000 Census population. ^bRegular home blood pressure monitor (HBPM) use defined as daily, weekly, or monthly. ^cFrom chi‐square test to estimate significant differences within each selected characteristic. ^dSome missing information in both 2005 and 2008.

Figure 1.

 Frequency of home blood pressure (BP) monitor (HBPM) use and perceived benefit of BP control among hypertensive adults—HealthStyles Surveys, 2008 (combined).

Multiple logistic regression analyses found that patients 65 years and older were significantly more likely (AOR, 2.38; 95% CI, 1.49–3.81) to be regular?HBPM users than those aged 35 to 44 years (Figure 2). Non‐Hispanic blacks were significantly less likely (AOR, 0.69; 95% CI, 0.55–0.86) to be regular HBPM users than non‐Hispanic whites, and compared with those having a household income ≥$60,000, those with an income <$25,000 (AOR, 0.75; 95% CI, 0.60–0.94) or $25,000–39,900 (AOR, 0.71; 95% CI, 0.55–0.92) were significantly less likely to be regular HBPM users. There were no significant differences in regular HBPM use by sex or education level.

Figure 2.

 Adjusted odds ratios with 95% confidence intervals of regular use of a home blood pressure monitor (HBPM) among hypertensive adults—HealthStyles Surveys, 2005 and 2008 (combined). Covariates in the models were age, sex, race, household income and education level. Regular HBPM use defined as daily, weekly, or monthly. Some missing information in both 2005 and 2008.

There was a 14.2% (95% CI, 9.2%–17.0%) RPC from 2005 to 2008 in the proportion of hypertensive adults who were regular HBPM users, a significant increase from 40.1% to 45.8% (P<.05; Figure 3). Hypertensive adults aged 35 to 44 years had the greatest RPC for regular HBPM use (RPC, 26.0%; P<.05, reflecting a rise from 26.9% to 33.9%) followed by those 65 years and older (RPC, 21.5%; P<.05, from 46.9% to 57.0%). The sample size for the youngest age group was too small for reliable estimates. The RPC for non‐Hispanic blacks was 41.9% (P<.05). Finally, there was a decrease in the RPC of being a regular HBPM user among hypertensive adult high school graduates (17.2%, P<.05).

Figure 3.

 Relative percent change (RPC) in the prevalence (%) of hypertensive adults who were regular users of home blood pressure monitor (HBPM), by select characteristics—Healthstyles, 2005 and 2008. RPC calculated using the formula ((T2 − T1)/T1) or ((2008 − 2005)/2005). Prevalences are weighted for age, sex, race, income, and household size to represent the US 2000 Census population. Regular HBPM use defined as daily, weekly, or monthly. Some missing information in both 2005 and 2008. ^* P<.05. †Sample size too small for reliable estimates.

Discussion

Regular BP monitoring by hypertensive patients can be an important tool for achieving goal BP levels and better adherence to antihypertensive therapy. ⁸ A meta‐analysis of 37 randomized controlled trials found that regular HBPM use correlated with twice as much reduction in the doses of antihypertensives used compared with patients whose BP was monitored in the clinic. ⁸ The majority of the clinical trials had specific titration protocols ⁸ that included daily or weekly HBPM use. Regular use of HBPMs as part of a hypertension management protocol has been found to help overcome therapeutic inertia (ie, a health care professional not changing the medication despite an elevated BP) ⁸ but there have been no reports to date on the prevalence of HBPM use among hypertensive adults.

Our study demonstrated that less than half of American hypertensive adults in 2005 and 2008 were regular HBPM users, regardless of socioeconomic characteristics. This conclusion should be taken with caution since the data source was a set of approximately 10,000 households that volunteered to be in the study. However, other studies using HealthStyles data have been shown to correlate well with self‐reported hypertension prevalence estimates from the Behavioral Risk Factor Surveillance System (BRFSS) of the CDC. ²⁷

From 2005 to 2008, there was a significant relative increase of 14.2% for regular HBPM use, which is encouraging, but the final percentage remained less than half. The 57.0% prevalence of regular use in 2008 for hypertensive adults 65 years and older is somewhat promising, but the fact that estimates for the other age groups were so much lower (none above 42.6% for the 45‐ to 64‐year age group) is disappointing. This is particularly disheartening because regular use of an HBPM should be seen as helpful for achieving optimal BP levels for adults of any age. Perhaps most important, regular HBPM use can enhance evaluation of how well BP is being controlled in patients who are taking antihypertensives. ²⁰ , ²⁸ , ²⁹ , ³⁰ , ³¹ , ³² Our study demonstrated that a higher proportion of hypertensive adults who monitored their BP more frequently were those who perceived a benefit. Health care professionals, community health workers (including promotores de salud), and public health agencies need to consider incorporating regular HBPM use to improve motivation and compliance among patients, especially younger hypertensive adults.

Our study indicates that the prevalence of regular HBPM use by hypertensive adults vary by sociodemographic factors. Among populations with hypertension, blacks have been found to have a higher prevalence of hypertension, earlier onset, more severe outcomes, and more clinical sequelae than non‐Hispanic whites. In addition, Mexican Americans have been found to have lower control rates than non‐Hispanic whites and blacks. ⁶ Education and income could affect the likelihood that someone would buy an HBPM, which can cost $30 to $150. Our study demonstrated that hypertensive adults in the younger age groups (18–45 years) and women, non‐Hispanic black, or Hispanic, or those who are from a low‐income household or have only a modest education were less likely to use HBPM regularly than other groups. It is hoped that the 2008 call to action by the American Heart Association, American Society of Hypertension, and the Preventive Cardiovascular Nurses Association for the use of HBPMs and their reimbursement by insurers ²⁰ , ²⁹ will not only increase the number of health care professionals who advocate for regular use of these devices, but also help those who cannot afford to buy a monitor.

Health care professionals should always promote regular HBPM use and ensure adequate education of the patient on the proper use of their device to ensure accurate measurements of the patient’s BP. ¹⁷ , ²⁰ , ²⁸ , ²⁹ , ³⁰ When helping a patient chose a validated HBPM, a list is available online at dabl Educational Trust Web site (http://www.dableducational.org/sphygmomanometers/devices_2_sbpm.html#ArmTable). Managing patients who wish to control their BP, clinicians should emphasize regular HBPM use and ensure their BP measurement accuracy compared with the clinical manometers. ⁴ Proper patient education is crucial for timing and techniques of taking BP readings. ²⁰ , ²⁸ , ²⁹ , ³⁰ HBPM is contraindicated for some patients. In general, for those with stable, controlled BP, HBPM use should be conducted a minimum of 1 week (preferably 2 times first thing in the morning and 2 times before bedtime) for an average BP every 3 months. Overuse of HBPM should be avoided. ²⁰ , ²⁸ , ²⁹ , ³⁰

Further research is needed to ascertain whether the use of an HBPM is a cost‐effective strategy to help reduce the serious acute sequelae of untreated hypertension. ⁸ , ¹⁰ , ¹² , ³³ , ³⁴ , ³⁵ Clearly, for the patient, knowing their target BP is vital to the initiation of proper patient action to control their hypertension. Regardless, clinicians and patients alike should be assured that regular use of an HBPM is an effective clinical strategy that should be used along with adopting or maintaining therapeutic lifestyle behaviors ³⁶ , ³⁷ to control BP. Further research is required to assess what is the optimal frequency of HBPM use that helps achieve their goals.

Study Limitations

The findings reported in this study should be viewed in light of 5 possible limitations. First, because HealthStyles is a mail survey, it reaches a sample population in which minority and low‐income households are underrepresented, although low‐income and minority households were supplemented to improve representation. Second, because the survey requires literacy in the English language, some non‐English–fluent households would not be able to participate, further limiting the representation of some minority populations. Third, the self‐reported data on which this survey is based may contain some degree of error: the tendency to give what are seen as socially desirable answers could provide overestimation, whereas shortcomings in recall could be sources of error for underestimation. Finally, the low response rate and small sample size are additional limitations that can also produce unreliable estimates. These concerns notwithstanding, the HealthStyles survey uses a national sample adjusted for age, sex, race, income, and household size to represent the 2000 US Census population, and there has been good correlation of these types of data with that from the BRFSS. ²⁷

Conclusions

According to our study, self‐reported regular HBPM use among US hypertensive adults increased from 2005 to 2008 but remained less than half. Since HBPM can assist with hypertension control, it should be promoted to improve BP control especially among hypertensives who are younger (ie, 18–35 years), non‐Hispanic black, Hispanic, or those with low income.

Disclaimer:  The findings and conclusions in this report are those of the authors and do not necessarily represent the official views of the CDC.