Hypertension control among patients referred by a community blood pressure screening program

Quality of clinical reports on behavioral interventions for hypertension

PURPOSE

The purpose of this study was to provide clinicians with the confidence to employ behavioral interventions for hypertension and to guide researchers in the development and reporting of studies.

METHODS

We systematically reviewed English language articles (1970-1999) describing behavioral interventions for hypertension, evaluating aspects of design, analysis, reporting of results, and factors that were associated with higher quality of these studies.

RESULTS

Of 100 articles, 49 were randomized controlled trials (RCT), 33 were observational studies with control groups, and 18 were observational studies without control groups; mean (SE) quality scores were 69.2 (1.6), 57.6 (5.3), and 60.3 (2.2), respectively. RCTs were more likely than observational studies to attain high scores in descriptions of appropriateness of control group, inclusion and exclusion criteria, study population, and the intervention protocol. In multivariate analysis, date of publication, reported funding source, and intervention type were independently associated with greater quality scores: 7.4 [95% CI: 0.03, 14.7] points greater for articles published 1990-1999 vs 1970-1979, 6.5 [95% CI: 1.4, 11.6] points greater for articles reporting government funding vs those not reporting funding sources, and 8.6 [95% CI: 0.3, 17.1], 12.9 [95% CI: 3.4, 22.4], and 14.2 [4.1, 24.4] points greater for articles examining patient education/support, change in delivery system, and mass health campaigns vs articles examining patient reminders, respectively.

CONCLUSIONS

While quality has improved over time, there is considerable room for improvement. Investigators should pay particular attention to description of study population and allocation of subjects, the use of standardized outcomes reporting, and appropriate statistical analysis.

Differences of blood pressure estimates between consecutive measurements on one occasion: implications for inter-study comparability of epidemiologic studies

Currently, substantial variation in epidemiologic studies exists regarding the number of blood pressure (BP) readings obtained and the way in which they are combined. This might result in systematically different BP estimates. We therefore analysed data from 25,891 subjects (10,124 men and 15,767 women) of the EPIC-Potsdam Study (European Prospective Investigation into Cancer and Nutrition) to estimate the magnitude of differences between consecutive BP readings and their combinations. Three measurements with 2 min intervals were performed in the sitting position on the right arm with the supported arm elevated at heart level by trained interviewers using oscillometric devices. Mean BP declined from first to second reading and further to third reading by systolic 5.0/0.9 mmHg in men and 4.9/0.8 mmHg in women and by diastolic 1.5/0.3 mmHg in men and 1.9/0.5 mmHg in women, as well as pulse pressure (PP) (3.5/0.6 in men, 3.0/0.3 in women) and hypertension prevalence (9.1/1.7%-points). The magnitude of BP decline depended on BP level, age, body mass index (BMI), and BP medication. Combinations including the first reading lead to generally higher estimates than subsequent readings or their combination. Published data on mean BP, PP and hypertension prevalence depend on the number and subsequent handling of BP readings which might introduce bias to the comparison of different studies unless the same defined readings were used. The combination of the second and third reading seems to be favourable over any single reading or other combinations.

Community control of hypertension at the worksite in a metallurgical factory: results of 1-year follow-up

This study was designed to assess advantages and cost-effectiveness of community control of hypertension at the worksite in a metallurgical factory in Pavia. Under consent of managers and trade-unionists, a screening program was undertaken. 2701 subjects (95% of the total number of employees) were screened: 277 (10.2%) were hypertensive, 101 (38%) did not know to be hypertensive, 56 (22%) knew to be hypertensive but they were untreated and only 20 (8%) of those under treatment were adequately treated. Of the 277 essential hypertensives, 262 (94%) adhered to the program. They were assigned to beta-blocking or diuretic treatment following WHO rules. Then an aggressive follow-up was started (the hypertensives were periodically called to control at the worksite). 257 (98%) were participants 1 year later. Our worksite hypertension control program allowed us to identify many cases of undiagnosed or untreated hypertension and to start an early treatment. One year after entry, the percentage of hypertensives achieving a normal blood pressure (85%) was almost twice as that obtained by conventional clinical approach employing the same type of treatment. Besides, more than 95% of hypertensives remained under control at 1 year. Regarding the costs, it is difficult to generalize, but our study suggests that, if there is the will, it is possible to realize programs of hypertension community control at a very low cost (in our experience: 43 dollars per hypertensive per year).

The Edgecombe County High Blood Pressure Control Program: III. Social support, social stressors, and treatment dropout

In a hypertension prevalence survey of a stratified random sample of 1,000 households, 2,030 adults (aged 18 years and over) were interviewed and information on psychosocial variables collected. Among 359 hypertensives, there was a consistent relationship between indicators of difficulty in the social environment and dropout from treatment in women. Compared to those who remained in treatment, women who dropped out can be characterized as having less social support on the job, having less perceived spouse approval (if married), having a lower level of perceived access to supportive resources, and being more likely to report feeling pushed most or all of the time if they are homemakers. Relationships between indicators of social support and dropout from treatment in men were found only with support on the job, and for White men, with perceived friend approval.

Effects of home blood pressure measurement on long-term BP control

This research reports level of blood pressure control and ability to maintain newly discovered hypertensives in a municipal hospital setting by use of family- and self-monitored home blood pressure units. Three hundred ninety-six patients were randomized into family- and self-monitored blood pressure groups and a control group. Findings indicate that the use of either self- or family-read cuffs is effective in the first six months of treatment in lowering blood pressures. The data are suggestive of a beneficial effect of the use of cuffs for up to 18 months; however, with additional time in the study, no differences in the level of blood pressure control could be demonstrated between groups. The use of family-monitored blood pressure cuffs produces a lower drop-out rate than does the use of no cuff. The effect on drop outs is substantial for the first year of treatment, but beyond 12 months, the family-read cuff is also more effective than no cuff in reducing drop outs.

Temporal effects of prompting on acceptance and follow-up in a community-based hypertension screening program

This study evaluated the effects of prompts and reinforcement on two aspects of hypertension control: a) attendance at a community-based blood pressure screening program and b) follow-up visits to a physician's office by persons identified through screening as at-risk clients. Baseline data showed a decreasing trend in attendance at the screening sessions and a 51% "no show" rate for physician follow-ups. Screening session attendance increased following intervention; however, attendance rates across weeks appeared to vary mainly as a function of the prompting schedule (monthly newsletter announcements ) rather than the availability of reinforcement. Finally, the intervention not only increased the percentage of at-risk clients who saw a physician, but also decreased the latency between the time of initial screening and the follow-up appointment.

The Edgecombe County High Blood Pressure Control Program: I. Correlates of uncontrolled hypertension at baseline

To guide the planning of a multifacetted hypertension control program in Edgecombe County, North Carolina, a baseline survey of a stratified (by township) random sample of 1,000 households was conducted. All adults (greater than or equal to 18 years) were interviewed and had their blood pressures (BP) measured. Five hundred thirty-nine individuals, 27 per cent of the survey population, had diastolic BP greater than or equal to 90 mm Hg or were receiving anti-hypertensive drug therapy. The 539 hypertensives were divided into seven subgroups reflecting successive stages in the control of hypertension based on the awareness, treatment, and control of their hypertension. Unaware hypertensives were further subdivided into three groups according to the recency of their last BP check, and those aware but untreated were subdivided by whether they had previously received treatment. The seven subgroups of hypertensives were compared, separately for women and men, with respect to sociodemographic characteristics, health behaviors, and health status. In general, the progression from undetected hypertension to treatment and control appeared to be associated with being older, female, and White. This progression was further associated with greater educational levels and higher family incomes among women and increasing self-reported morbidity among men. The implications for intervention of these and other described associations are discussed.

Management of hypertension newly detected by health screening

An attempt was made, through a hospital-based health screening service, to ensure proper longterm care of clients with hypertension and other cardiovascular risk factors. Of 8755 subjects screened on one occasion, 1274 (14.6%) had a blood pressure reading above defined limits; of these, 1058 were not receiving antihypertensive drugs. Apparently hypertensive subjects were rescreened within one week or were referred to their local doctors. At their second visits, over half of the 716 rescreened subjects had reading consistently below the defined limits. Those with intermittent blood pressure elevation (89 patients) were designated as having labile hypertension, and were reviewed regularly. The remainder, with persisting hypertension, were sent to their local doctors or to the hospital's hypertension clinic. After six months, the group ith labile hypertension showed no change in mean left cardiac ventricular voltage, and more than 50% the group had normal blood pressure; 14 patients were receiving antihypertensive drugs. Subjects referred to the hypertension clinic had a high prevalence of cardiovascular risk factors and a low prevalence of clinically evident organ damage. Only half of this group were deemed to require drug therapy. In a postal survey of clients referred to private doctors, 35% of respondents reported that they had started taking anti-hypertensive drugs. Thorough rescreening of blood pressure is essential in preventing the unnecessary use of antihypertensive drugs, and this can be facilitated by providing management streams appropriate to the needs of the individual subject.

Effect of counselling rejected blood donors to seek health care

The appropriate public health role of a blood bank has not been completely defined. An evaluation of verbal counselling as an incentive for rejected blood donors to seek follow-up medical care was undertaken. Two groups, deferred from donating blood because of low hematocrits, were compared in terms of compliance rate (percentage seeking medical care). The first group, comprising 60 individuals deferred in a traditional manner with either a brief written or verbal statement, had a compliance rate of 25%. In the second group, comprising 61 individuals to whom additional counselling was offered, 79% requested such counselling. A compliance of 60% was found among those counselled, and an overall compliance rate of 54% was noted in the group as a whole. The more than doubling of the compliance rate indicates that a blood bank can effectively encourage deferred donors, most of whom are asymptomatic, to seek health care.