Effects of 24-hour ambulatory blood pressure monitoring on daily activities.

Compared the self-monitored activities, locations, and postural positions of 28 hypertensives while they wore an alarm watch and then while they wore a 24-hr ambulatory blood pressure monitor (ABPM) to see if wearing the ABPM led to alterations in behavior. Within the limitations of the study (no counterbalancing of order and twice as many ABPM measures as watch measures), we found significant differences in frequency of being at home or in miscellaneous settings, in standing and reclining positions, and in mental, physical and miscellaneous activities between the two occasions.

The relationship between 24-hour ambulatory blood pressures and laboratory measures of cardiovascular reactivity.

The relationship between 24-hour ambulatory blood pressures (ABP) and blood pressures (BP) obtained during laboratory stressors was examined. Thirty normotensives (equal males and females) underwent ABP monitoring on three occasions separated by a week. They also underwent a laboratory assessment which included standard stressors (i.e., mental arithmetic, cold pressor, orthostatic response, treadmill exercise). Correlational analyses found laboratory pressures to be significantly correlated with ambulatory pressures, with laboratory baseline BPs showing higher correlations to the ambulatory BPs than the BPs obtained during laboratory stressors. In addition, gender effects were examined. In the correlational analyses between ABPs and laboratory BPs, males and females did not differ significantly in the strength of the correlations. In terms of absolute values, males were found to have significantly higher SBP during ambulatory monitoring, random-zero recordings, calibration readings, and during baselines of the laboratory assessment. There were no gender effects for these measures with respect to diastolic blood pressure or heart rate. There were also no gender effects on reactivity to laboratory stressors as measured by change scores. Exploratory analyses found no significant effect of history of familial hypertension on either the ABPs or the laboratory pressures.

Test-retest reliability of 24-hour ambulatory blood pressures.

The test-retest reliability of 24-hour ambulatory blood pressures (ABP) was examined using correlational analyses as well as idiographic and nomothetic time-series regression analyses. Thirty normotensives (equal males and females) underwent ABP monitoring on three occasions, each of which was separated by a week. When analyzing the data, various postural positions, activities, and locations were controlled for in order to differentially assess the effects of these variables independently. Correlational analyses found the overall test-retest reliability of the ABPs to be quite good (SBP r = .84-.88, DBP r = .83-.86, HR r = .91-.95). Correlations examined within specific postural positions, activities, and locations were also significant. The time-series regression analyses used confirmed the reproducibility of the ABPs, with no greater than 20% of the subjects showing significant changes in ABPs over the three monitoring periods. Gender effects were also examined. In general, males had significantly higher systolic ABPs overall, although there was no influence of gender in terms of the test-retest reliability of the ABPs.

Subjective experiences associated with thermal biofeedback treatment of hypertension.

Reports of subjective experiences of 73 hypertensive patients who were treated with thermal biofeedback for hand warming were obtained over 16 treatment sessions. Most of the differential responding in subjective report occurred in the first 5 sessions. Differences in reports of throbbing were associated with medication status during treatment (presence of sympatholytic antihypertensive agent). From 4 to 9% of patients report negative subjective experiences at any one session. When short-term clinical successes (either elimination of medication or reduction of BP) were compared with short-term failures, it was found that successes reported more warmth, more likelihood of falling asleep, and more dreamlike experiences. The latter were more likely to occur suddenly for the successes. Correlational analyses revealed consistent positive associations between reports of warmth and relaxation with highest temperature achieved in the session and consistent negative associations between experiencing physical sensations and degree of temperature change within the session.

Thermal biofeedback as an effective substitute for sympatholytic medication in moderate hypertension: a failure to replicate.

Thirty-three moderate hypertensives were converted to a 2-drug regimen of metoprolol and diuretic and BPs stabilized at a well-controlled level. They then completed one of three conditions over an 8-week interval: (I) 16 sessions of TBF (hand and foot warming); (II) 16 sessions of frontal EMG-BF; (III) regular home monitoring of BP. Attempts were then made to withdraw the patients from the sympatholytic medication. Those successfully withdrawn were followed up for one year. There were no significant advantages for TBF over the other two conditions in the short term or with long-term follow-up. Only 27% of treated patients (including Condition III failures who were remedicated and treated with TBF) were successfully off of the sympatholytic at a one-year follow-up. The generally poor results on clinical outcome were confirmed by clinic BPs, home BPs by patients, and 24-hour ambulatory BPs.