Objectives.This article summarizes the results of 153 studies published between 1977 and 1994 that evaluated the effectiveness of interventions to improve patient compliance with medical regimens.Methods.The compliance interventions were classified by theoretical focus into educational, behaviora

Effectiveness of Interventions to Improve Patient Compliance a Meta-Analysis

Intracellular free calcium has been implicated in vascular smooth-muscle contraction and in the pathophysiology of essential hypertension. We studied free-calcium levels in blood platelets, which have many features in common with vascular smooth-muscle cells. With use of an intracellularly trapped fluorescent dye, the free-calcium concentration in platelets was found to be elevated in 9 patients with borderline hypertension and 45 patients with established essential hypertension, who were compared with 38 normotensive subjects. There was a close correlation between the free-calcium level and both systolic and diastolic blood pressure (n = 92; r = 0.883 for systolic pressure and 0.931 for diastolic pressure; P<0.001 for both). Antihypertensive treatment with calcium-entry blockers (n = 15), beta-adrenoceptor blockers (n = 12), or a diuretic (n = 6) resulted in a reduction in free calcium, and this correlated with the fall in blood pressure (P<0.001). The intracellular free-calcium concentration in...

Correlation of platelet calcium with blood pressure. Effect of antihypertensive therapy.

Numerous studies addressed the predictive value of the nighttime blood pressure (BP) as captured by ambulatory monitoring. However, arbitrary cutoff limits in dichotomized analyses of continuous variables, data dredging across selected subgroups, extrapolation of cross-sectional studies to prospective outcomes, and lack of comprehensive adjustments for confounders make interpretation of the literature difficult. We reviewed prospective studies with total mortality or a composite cardiovascular end point as an outcome in relation to the level and the circadian profile of systolic BP. We analyzed studies in hypertensive patients (n=23 856) separately from those in individuals randomly recruited from populations (n=9641). We pooled summary statistics and individual subject data, respectively. In both patients and populations, in analyses in which nighttime BP was additionally adjusted for daytime BP and vice versa, nighttime BP was a stronger predictor than daytime BP. With adjustment for the 24-hour BP, both the night-to-day BP ratio and dipping status remained significant predictors of outcome but added little prognostic value over and beyond the 24-hour BP level. In the absence of conclusive evidence proving that nondipping is a reversible risk factor, the option whether or not to restore the diurnal blood pressure profile to a normal pattern should be left to the clinical judgment of doctors and should be individualized for each patient. Current guidelines on the interpretation of ambulatory BP recording need to be updated.

Predictive Role of the Nighttime Blood Pressure

Chronobiology is the science concerned with investigations of time-dependent changes in physiological variables. Circadian rhythms refer to variations that recur every 24 hours. Many physiological circadian rhythms at rest are endogenously controlled, and persist when an individual is isolated from environmental fluctuations. Unlike physiological variables, human performance cannot be monitored continuously in order to describe circadian rhythmicity. Experimental studies of the effect of circadian rhythms on performance need to be carefully designed in order to control for serial fatigue effects and to minimise disturbances in sleep. The detection of rhythmicity in performance variables is also highly influenced by the degree of test-retest repeatability of the measuring equipment. The majority of components of sports performance, e.g. flexibility, muscle strength, short term high power output, vary with time of day in a sinusoidal manner and peak in the early evening close to the daily maximum in body temperature. Psychological tests of short term memory, heart rate-based tests of physical fitness, and prolonged submaximal exercise performance carried out in hot conditions show peak times in the morning. Heart rate-based tests of work capacity appear to peak in the morning because the heart rate responses to exercise are minimal at this time of day. Post-lunch declines are evident with performance variables such as muscle strength, especially if measured frequently enough and sequentially within a 24-hour period to cause fatigue in individuals. More research work is needed to ascertain whether performance in tasks demanding fine motor control varies with time of day. Metabolic and respiratory rhythms are flattened when exercise becomes strenuous whilst the body temperature rhythm persists during maximal exercise. Higher work-rates are selected spontaneously in the early evening. At present, it is not known whether time of day influences the responses of a set training regimen (one in which the training stimulus does not vary with time of day) for endurance, strength, or the learning of motor skills. The normal circadian rhythms can be desynchronised following a flight across several time zones or a transfer to nocturnal work shifts. Although athletes show all the symptoms of 'jet lag' (increased fatigue, disturbed sleep and circadian rhythms), more research work is needed to identify the effects of transmeridian travel on the actual performances of elite sports competitors. Such investigations would need to be chronobiological, i.e. monitor performance at several times on several post-flight days, and take into account direction of travel, time of day of competition and the various performance components involved in a particular sport. Shiftwork interferes with participation in competitive sport, although there may be greater opportunities for shiftworkers to train in the hours of daylight for individual sports such as cycling and swimming. Studies should be conducted to ascertain whether shiftwork-mediated rhythm disturbances affect sports performance. Individual differences in performance rhythms are small but significant. Circadian rhythms are larger in amplitude in physically fit individuals than sedentary individuals. Athletes over 50 years of age tend to be higher in 'morningness', habitually scheduling relatively more training in the morning and selecting relatively higher work-rates during exercise compared with young athletes. These differences should be recognised by practitioners concerned with organising the habitual regimens of athletes.

Circadian variation in sports performance.

Recommendations for the use of home (self) and ambulatory blood pressure monitoring. American Society of Hypertension Ad Hoc Panel.

The effects of shifted working and sleeping phases on the diurnal blood pressure rhythm were investigated in 15 physically working industrial shift workers at a slowly rotated three-shift system. Ambulatory 24-h blood pressure monitoring was performed during the morning and night shifts. In the two

Twenty-four-hour blood pressure is not dependent on endogenous circadian rhythm

1. The intracellular Na + and Ca 2+ activity and Na + concentration were measured in erythrocytes of normotensive subjects, with and without a familial disposition to hypertension, in essential hypertensive patients with and without a family history of hypertension, and in patients with secondary hypertension. 2. In normotensive subjects without a genetic trait of hypertension intracellular Na + activity and concentration were 7.00 ± 1.38 mmol/l and 5.67 ± 0.95 mmol/l respectively. The intracellular Ca 2+ activity was 4.82 ± 4.49 μmol/l. In normotensive subjects with a familial hypertensive disposition intracellular Na + activity and concentration were 9.74 ± 1.43 mmol/l ( P P 2+ was 9.59 ± 9.71 μmol/l ( P 3. Essential hypertensive patients without a familial genetic trait had an elevated intracellular Na + activity (8.35 ± 2.08 mmol/l, P + concentration was 6.64 ± 0.79 mmol/l ( P 2+ activity was markedly elevated to 25.33 ± 19.03 μmol/l ( P + activity (17.19 ± 4.37 mmol/l, P 2+ activity (32.8 ± 32.51 μmol/l, P + concentration was 6.25 ± 1.23 mmol/l. 4. The results indicate that in essential hypertension intracellular Na + activity is increased, particularly in patients with a familial disposition for hypertension. Intracellular Ca 2+ is increased in essential hypertension whether or not there was a family disposition to hypertension.

http://portlandpress.com/clinsci/article-pdf/63/s8/41s/742868/cs063041s.pdf

Intracellular Na+ and Ca2+ Activities in Essential Hypertension

Circadian blood pressure rhythms were examined in subjects exhibiting various forms of secondary and essential hypertension and in normotensive subjects with and without renal disease. Indirect ambulatory blood pressure recordings were performed in 284 subjects for 24 h. In contrast to patients with essential hypertension and to normotensive healthy subjects, the circadian fluctuations of blood pressure were reduced in secondary hypertensives and in normotensive renal patients. In renal hypertensives, these alterations in the diurnal blood pressure variations were dependent on the degree of renal failure. Calculations based on comparisons of the mean sleeping and mean daytime blood pressures identified 89.8% of the essential hypertensives and 72.5% of the patients with secondary hypertension. A large proportion of the patients with secondary hypertension had very high blood pressure levels during sleep, in many cases even exceeding the daytime levels. Thus, 24-h ambulatory blood pressure curves from patients with secondary and essential hypertension can be distinguished from each other. In secondary hypertension, blood pressure monitoring during both day and night is particularly useful for evaluating frequently severe nocturnal hypertension, which may require particular treatment.

Can secondary hypertension be identified by twenty-four-hour ambulatory pressure monitoring?

Intracellular sodium and calcium activities were measured by ion-selective electrodes in red blood cells of primary hypertensives and of normotensives with and without a familial disposition to hypertension. Intraerythrocytic sodium activity was markedly elevated in patients and normotensives with a familial disposition to hypertension (15.16±2.35 mmol/l in hypertensives and 9.74±1.43 mmol/l in normotensives, respectively, mean value±sD) as compared to the corresponding group without such a history (8.35±2.08 mmol/l in hypertensives and 7.00±1.38 mmol/l in normotensives). Mean intraerythrocytic calcium activity showed the highest values in patients with hypertension (32.8±32.5 µmol/l in patients with and 25.3±19.0 µmol/l in those without a familial disposition to hypertension), whereas in normotensives mean calcium activity was much lower (9.6±9.7 and 4.8±4.5 µmol/l, respectively). Our results document that a disturbed intraerythrocytic sodium metabolism is limited to patients with essential hypertension and a familial disposition to hypertension and, to a lesser extent, to normotensives showing a familial disposition to hypertension. Thus, a genetically determined alteration in intracellular sodium can be assumed. Furthermore, the observation of an enhanced intraerythrocytic calcium in some essential hypertensives with and without a familial disposition suggests additional factors, other than sodium, responsible for the disturbed intracellular calcium balance in these patients.

Intracellular sodium and calcium in essential hypertension.

A multidimensional behavioral program was developed for the treatment of essential hypertension. Over a course of 6 weeks, 108 patients of a rehabilitation center were treated with this program consisting of health education, self-monitoring of blood pressure, relaxation techniques, and a social skill training in addition to standard medical treatment alone. Blood pressure and other cardiovascular risk factors were monitored for a period of 12 months. Blood pressure levels became normotensive in both groups at the end of the 6-week training program. However, the blood pressure reduction in the behavioral treatment group was achieved with fewer patients taking antihypertensive medication than in the control group. The number of patients taking antihypertensive drugs in the treatment group was 60.2% prior to treatment and 44.4% after treatment; figures for the control group were 68% and 73.8%, respectively (p less than or equal to 0.01). Almost identical data were obtained at the 6- and 23-month follow-up examinations. No consistent changes were observed in weight, smoking, or blood lipids. These results demonstrate beneficial and long-lasting effects of a combined medical and psychologic treatment of essential hypertension as compared to medical treatment alone.

Dorst Kg

Papers

Twenty-four-hour blood pressure is not dependent on endogenous circadian rhythm

Intracellular Na+ and Ca2+ Activities in Essential Hypertension

Can secondary hypertension be identified by twenty-four-hour ambulatory pressure monitoring?

Intracellular sodium and calcium in essential hypertension.

Long-term effects of a complex behavioral treatment of essential hypertension.