Impact of antihypertensive medication adherence on blood pressure control in hypertension: the COMFORT study

BACKGROUND

It has not been fully elucidated whether antihypertensive medication adherence affects blood pressure (BP) control in hypertension cases.

AIM

To investigate the association of adherence to antihypertensive drug regimens and BP control using data from the Combination Pill of Losartan Potassium and Hydrochlorothiazide for Improvement of Medication Compliance Trial (COMFORT) study.

DESIGN

An observational analysis from a randomized controlled trial.

METHODS

A total of 203 hypertensive subjects were randomly assigned to a daily regimen of a combination pill (losartan 50 mg/hydrochlorothiazide 12.5 mg) or two pills, an angiotensin II receptor blocker and a thiazide diuretic. Medication adherence calculated based on pill counts and BPs was evaluated at 1, 3 and 6 months after randomization.

RESULTS

The subjects were divided into three groups according to their adherence, i.e. relatively low-adherence (<90%; n = 19), moderate-adherence (90-99%; n = 71) and high-adherence (100%; n = 113) groups. Clinical characteristics of the subjects including BP, sex, randomized treatments and past medical history did not differ significantly among the three groups. Achieved follow-up BPs over the 6-month treatment period, which were adjusted for age, sex, baseline BP and randomized treatment, were significantly higher in the low-adherence group (135/78 mmHg) compared with the high-adherence (130/74 mmHg; P = 0.02/0.02) and the moderate-adherence (128/74 mmHg; P = 0.003/0.02) groups.

CONCLUSION

Low adherence to an antihypertensive-drug regimen was associated with poor BP control.

Circadian characteristics of urinary melatonin from clinically healthy young women at different civilization disease risks

Rhythm characteristics in the about-daily (circadian) and about-yearly (circannual) frequency ranges were assessed for urinary melatonin. Clinically healthy women in Minnesota, USA, and Kyushu, Japan, were sampled around the clock once in 1-4 seasons. Possible differences that could reflect the large difference in breast cancer incidence in these two geographic locations were investigated. Each subject's risk of developing breast cancer, cardiovascular diseases resulting from an elevated blood pressure, and emotional conditions was numerically evaluated according to epidemiologic questionnaires. A prominent circadian rhythm characterizes urinary melatonin in both populations, peaking in the middle of the night. The American women exhibit a larger circadian rhythm-adjusted mean (mesor) than do the Japanese women. A circannual rhythm is also apparent in the North American women, but not in the Japanese women. The circadian mesor of urinary melatonin correlates negatively with the risk score of emotional depression and positively with that of developing cardiovascular diseases.

Improvement of blood pressure control in a hypertension clinic: a 10-year follow-up study

The objective of the study was to assess whether the publication of new guidelines, such as JNC VI 1997 and WHO/ISH 1999, and the development of new antihypertensive drugs have improved blood pressure (BP) control. A total of 150 patients (age 29-88, mean 66+/-11 years in 2001) who were followed at our hypertension clinic during 1991-2001 were retrospectively investigated. We compared the clinical characteristics of the patients in 2001 to those in 1991 and 1996, using the averaged BP determined at two occasions each year for our analysis. The average BP decreased during the 10 years between 1991 and 2001. When good BP control was defined as <140/90 mmHg, the rate of patients with good BP control increased from 31% in 1991 to 43% in 1996, and to 57% in 2001 (P<0.001 vs 1991). Both younger (< or =64 years) and older (> or =65 years) patients showed similar improvement during these 10 years. In 2001, satisfactory BP control (<130/85 mmHg) was achieved in 24% of younger patients, which was significantly higher than the achievement in 1991 (10%, P=0.02). This improvement occurred at the same time as an increase in the prescription of Ca antagonists and angiotensin II antagonist. The patients with improved BP control during these 10 years (n=50) showed lower body mass index (BMI) and serum total cholesterol levels in 2001 compared to persistently uncontrolled patients (n=54). Furthermore, the change in BMI during these 10 years was significantly less in the patients with improved BP control than in the persistently uncontrolled patients. In conclusion, BP control improved in the 10 years studied, and it seems to be attributable to the more frequent use of the newer drugs such as angiotensin II antagonists and Ca antagonists, to lifestyle modification and also to the growth in awareness of the importance of strict BP control.

Relationships of the systolic blood pressure response during exercise with insulin resistance, obesity, and endurance fitness in men with type 2 diabetes mellitus

The purpose of the present study was to investigate the relationships among the resting systolic (SBP) and diastolic blood pressure (DBP) or SBP response during exercise with insulin resistance evaluated by a homeostasis model (HOMA-IR), abdominal fat accumulation (visceral fat area [VFA], subcutaneous fat area [SFA]) by computed tomography (CT), and an estimation of the maximal oxygen uptake (V*O2max) in 63 Japanese middle-aged male patients with type 2 diabetes mellitus (type 2 DM). Body mass index (BMI) and waist-to-hip ratio (WHR) in type 2 DM subjects were significantly higher than in age-matched healthy male control subjects (n = 135) with normal glucose tolerance. Resting SBP (127.7 +/- 16.2 mm Hg v 119.4 +/- 13.0 mm Hg) and DBP (82.2 +/- 11.9mmHg v 76.8 +/- 9.4 mm Hg) levels, and the percentage of hypertension (20.6% v 1.5%) in type 2 DM subjects were significantly higher than in the control subjects (P <.05). According to a multiple regression analysis for resting blood pressure in type 2 DM, VFA was found to be an independent predictor of SBP, while V*O2max and HOMA-IR were independent predictors of DBP. In the controls, however, HOMA-IR was not found to be a significantly independent predictor for either resting SBP or resting DBP. Measurement of the SBP response during graded exercise using a ramp test was performed by an electrical braked cycle ergometer in 54 patients with type 2 DM only. The SBP was measured at 15-second intervals during exercise. The exercise intensity at the double product breaking point (DPBP), which strongly correlated with the exercise intensity at the lactate threshold, was used as an index for the SBP response to standardized exercise intensity. The SBP corresponding to exercise intensity at DPBP (SBP@DPBP) was evaluated as an index of the SBP response to standardized exercise intensity. The change in SBP (deltaSBP = SBP@DPBP - resting SBP) was significantly and positively associated with log area under the curve for glucose (log AUCPG) during a 75-g oral glucose tolerance test (OGTT). In addition, deltaSBP significantly and negatively correlated with the log area under the curve for insulin (log AUCIRI) and log AUCIRI/log AUCPG. Based on these results, insulin resistance was suggested to be independently associated with the resting DBP and SBP response to standardized exercise intensity in type 2 DM patients.

Magnetic circular dichroism properties of reaction center complexes isolated from the zinc-bacteriochlorophyll a-containing purple bacterium Acidiphilium rubrum

Reaction center (RC) complexes isolated from a Zn-bacteriochlorophyll (BChl) a-containing purple bacterium, Acidiphilium rubrum, were characterized by absorption, circular dichroism, and magnetic circular dichroism (MCD) spectroscopy. The oxidized-minus-reduced difference spectra indicated that, in this RC, the Zn-BChl a is the primary electron donor. The molecular structure of the donor was examined by measuring the ratio of the MCD intensity of the Faraday B-term (B) to the dipole strength (D). In the Q(y) region, B/D for the donor was about half those of bacteriopheophytin a and the accessory Zn-BChl a, indicating that the primary electron donor is a dimer. The magnitude of bleach of the Q(x) band was half that observed in Rhodobacter sphaeroides, suggesting the cation is localized on a single Zn-Bchl a. The absorption intensity of the higher-energy Q(y) exciton band was approximately 28% of that of the lower-energy band, and the exciton splitting was approximately 570 cm(-1), smaller than that in Rb. sphaeroides. These results indicate that, in A. rubrum, the primary electron donor is a Zn-BChl a dimer but that the interaction between the two molecules is rather weak. On the basis of these results, an adaptive strategy for changes in BChl a species is discussed from an evolutionary perspective.

Uphill energy transfer in a chlorophyll d-dominating oxygenic photosynthetic prokaryote, Acaryochloris marina

The steady-state fluorescence properties and uphill energy transfer were analyzed on intact cells of a chlorophyll (Chl) d-dominating photosynthetic prokaryote, Acaryochloris marina. Observed spectra revealed clear differences, depending on the cell pigments that had been sensitized; using these properties, it was possible to assign fluorescence components to specific Chl pigments. At 22 degrees C, the main emission at 724 nm came from photosystem (PS) II Chl d, which was also the source of one additional band at 704 nm. Chl a emissions were observed at 681 nm and 671 nm. This emission pattern essentially matched that observed at -196 degrees C, as the main emission of Chl d was located at 735 nm, and three minor bands were observed at 704 nm, 683 nm, and 667 nm, originating from Chl d, Chl a, and Chl a, respectively. These three minor bands, however, had not been sensitized by carotenoids, suggesting specific localization in PS II. At 22 degrees C, excitation of the red edge of the absorption band (which, at 736 nm, was 20 nm longer than the absorption maximum), resulted in fluorescence bands of Chl d at 724 nm and of Chl a at 682 nm, directly demonstrating an uphill energy transfer in this alga. This transfer is a critical factor for in vivo activity, due to an inversion of energy levels between antenna Chl d and the primary electron donor of Chl a in PS II.

Plasma concentrations of angiotensin metabolites in young male normotensive and mild hypertensive subjects

The plasma concentrations of angiotensin (Ang) I, Ang II, and their metabolites (Ang (3-8), (4-8), (5-8), and (3-4)) following in vitro ACE inhibitory activity were examined in young male normotensive (NT) (n = 7), and mild hypertensive (HT) volunteers (n = 6). There were no differences in supine plasma levels of Ang I, Ang II, and Ang (5-8) between the NT and HT groups: Ang I, 304 +/- 43 fmol/ml vs. 293 +/- 15 fmol/ml; Ang II, 32 +/- 6 fmol/ml vs. 43 +/- 10 fmol/ml; Ang (5-8), 176 +/- 22 fmol/ml vs. 133 +/- 32 fmol/ml. In addition, there were no significant differences between groups in any of these Ang levels when measured after standing for 60 min. However, the HT group showed significantly reduced supine and upright plasma Ang (3-8) and Ang (3-4) levels as compared to the NT group. In particular, the supine plasma level of Ang (3-4) (71 +/- 13 fmol/ml-plasma) in the HT group was significantly (1/3-fold) lower than that in the NT group (197 +/- 35 fmol/ml-plasma). An inverse correlation between the plasma level of Ang (3-4) and the upright systolic blood pressure (r = -0.627, p < 0.02, n = 13) was observed, indicating that the metabolism of Ang (3-4) might have been associated with the change in blood pressure.

Rationale for time-qualified reference standards for 24-hour blood pressure values and their circadian rhythms in Japanese normotensive adults: a study by the Ambulatory Blood Pressure Monitoring Research Group

The aim of this study was to demonstrate that blood pressure (BP) has to be standardized according to its circadian variability, including the properties shown in its circadian rhythm. The BP time-qualified standards were derived from a sample of 644 clinically healthy normotensive Japanese subjects (320 males, 324 females; age range, 18-93 years), stratified by age-group and gender, who underwent noninvasive ambulatory monitoring according to a fixed protocol. The monitored data series shows that BP exhibits a within-day variability at any age of life in both males and females. Additionally, the monitored data series shows that BP exhibits a significant circadian rhythm at any age of life in both males and females. The age- and sex-related reference limits for the BP within-day variability constitute the time-qualified standards against which both the casual and monitored BP measurements can be compared in order to detect whether or not they are compatible with normotension. The reference limits for the BP circadian rhythm represent the rhythmometric standards against which the BP oscillatory curve can be compared in order to detect whether or not they are compatible with a physiological circadian rhythm.

Age-related changes in blood pressure twenty-four-hour pattern in normotensive subjects of two populations

OBJECTIVES

This study investigates the systolic (S) and diastolic (D) blood pressure (BP) 24-h pattern in normotensive healthy subjects belonging to two populations characterized respectively by a "non-salt culture" (Italian subjects) and a "salt culture" (Japanese subjects) in their dietary salt intake (4-6 g/day in Italians vs 10-12 g/day in Japanese). The comparison was performed by taking into consideration the within-day variability (WDV) and circadian rhythmicity (CR) of BP with respect to age.

MATERIALS AND METHODS

Subjects investigated were 862 normotensive healthy subjects (308 Italians and 554 Japanese), stratified by age from 16 to 75 years, who volunteered for a noninvasive BP monitoring in an ordinary day of their life. The SBP and DBP time series were analyzed via conventional parametric statistics as well as chronobiological procedures.

RESULTS

The biometric estimates demonstrate that BP changes in its WDV and CR as a function of age in both populations. Despite the difference in their habitual salt intake, the age-related changes in BP WDV and CR result to be almost comparable at the cross-sectional contrasts, giving origin to age-related trends for SBP and DBP which are significantly parallel.

CONCLUSIONS

The comparability of BP WDV and CR in the two populations with a substantial difference in salt intake suggests that the normotensive status in human races is realized despite the difference in their habitual salt intake. This implies the ancestral development of mechanism(s) of adaptation to the possible "sodium luxus consumption". Although the adaptive mechanisms which provide a normotensive regimen under different conditions of sodium intake are almost unexplored, the racial adaptation to dietary salt constitutes, however, the initial condition for the cause-effect nexus between dietary salt intake and hypertension in human populations.

The human blood pressure chronome: a biological gauge of aging

OBJECTIVE

This study examines changes in the broad time structure (chronome) of blood pressure (BP) as a function of age.

DESIGN

This is an observational study.

SETTING

The study was conducted at the Chronobiology Laboratories of the University oi Minnesota, Minneapolis, Minnesota.

PARTICIPANTS

Seventy-two individuals 12 to 106 years of age provided a 7-day record of BP measured indirectly with an ambulatory monitor, mostly at 15-60-minute intervals.

MAIN OUTCOME MEASURES

Amplitudes in least squares spectra at frequencies of 1 to 7 cycles per week and 1 to 8 cycles per day were analyzed by linear regression as a function of age. A two-way analysis of variance for subjects classified in four age groups tested for any variance transposition from the circadian (about-daily) to the infradian (frequency lower than one cycle per day) and/or to the ultradian (frequency higher than one cycle per day) domain.

RESULTS

The decreasing circadian BP amplitude with age is accompanied by an increase in infradian and ultradian prominence. The day-to-day variability in circadian characteristics also increases with age.

CONCLUSION

A variance transposition from the circadian to the neighboring ultradian and infradian domains characterizes the elderly human BP chronome, as a new, technically implementable biological, rather than chronological, gauge of human aging.

Evidence from a chronobiometric approach that chronic smokers, although normotensive, show an increase in diurnal blood pressure

OBJECTIVE

To investigate the effects of chronic smoking on the 24 h blood pressure and heart rate pattern in normotensive subjects.

METHODS

Twenty-five smokers and 25 age-, weight- and height-matched non-smokers, who were all clinically healthy young men, gave their informed consent to undergo non-invasive, automated, ambulatory blood pressure monitoring for 24 h. The smokers in this study consumed on average 25.4 cigarettes per day. The lifestyle of the two groups was comparable because they worked as clerks at the same company. The 24 h blood pressure and heart rate data were analysed according to chronobiological methods.

RESULTS

Smokers were found to show a statistically significantly higher blood pressure versus non-smokers by day but not by night. Furthermore, smokers showed a slight increase in the mean level of circadian blood pressure rhythm versus non-smokers, accompanied by an amplification of one cyclic component of this periodicity.

CONCLUSIONS

The increase in diumal blood pressure in smokers might be regarded as the haemodynamic effect of chronic smoking in normotensive subjects. Such an effect seems to be substantiated pathophysiologically by an amplitude overmodulation of one of the harmonic components which confer the circadian blood pressure rhythmicity. Because the diumal increase in blood pressure persists for two-thirds of the day-night period, one can argue that this phenomenon in normotensive smokers might be a premonitory sign of future hypertension. Apart from this, one can hypothesize that the diumal increase in blood pressure might itself be a cause of target organ damage, given its consistent within-day duration and daily repetition.

Circadian rhythm of blood pressure and life style: a study of clinically healthy subjects living in rural and industrialized countries

The aim of this study is to investigate how the blood pressure (BP) circadian rhythm (CR) is influenced by life style. Two groups of subjects were recruited from Nepal and Japan because of the extremely different occupational routines of these countries. The Nepalese represent a rural culture, while the Japanese reflect an industrialized civilization. Both the ethnic groups have in common a high dietary sodium intake. The BP monitoring was estimated according to chronobiological methods. Results provide evidence for a phase difference in BP CR which is coherent with the life style in the two groups. Furthermore, the estimates demonstrate that the Japanese show a higher level in daily BP which is related to the greater number of hours in which they are active. These findings may be taken into account for better deciphering of what is the role of life style on BP physiology in human beings.

Human T-lymphotropic virus type-I, and hepatitis A, B and C viruses in Nepal: a serological survey

In 1987, 676 blood samples were collected from inhabitants of the Bhadrakali and Kotyang villages in Nepal. The samples were tested for the prevalence of antibody to hepatitis A virus (anti-HAV), hepatitis B surface antigen (HBsAg), antibody to hepatitis B core antigen (anti-HBc), second-generation antibody to hepatitis C virus (anti-HCV) and antibody to human T-lymphotropic virus type-I (anti-HTLV-I). Anti-HAV was present in 99.3% of the people surveyed. The prevalence of anti-HAV reached 100% in the < 25 age group and was as high or only slightly lower in all other age groups. The prevalence of HBsAg was 0.3% and of anti-HBc 7.7%. Anti-HCV was found in 0.1% of the residents. No significant difference by gender or village was noted in the prevalence of anti-HAV, HBsAg, anti-HBc, or anti-HCV. No anti-HTLV-I-positive persons were identified. These data suggest that the prevalence of hepatitis B and C virus infections in Nepal is low in contrast to hepatitis A virus infection, and that human T-lymphotropic type-I infection may be absent in this population.

Seasonal variation in 24-h blood pressure pattern of young normotensive women

To investigate the seasonal variations in ambulatory blood pressure patterns, 24-h blood pressure was measured every 15 minutes noninvasively in ten young normotensive women. Urine was collected every 4 hours. The examinations were repeated in spring, summer, autumn, and winter in a standardized living environment. The 24-h average systolic and diastolic blood pressures did not differ significantly among the seasons. Similarly, there were no significant differences in the average values of either daytime or nighttime blood pressure. In contrast, the average pulse rate during nighttime was significantly higher in winter than in summer (64 +/- 2 beats/min vs. 59 +/- 2 beats/min, p < 0.05). The variabilities of either blood pressure or pulse rate did not change significantly among the seasons. The mesors and acrophases of both systolic and diastolic blood pressures, determined by a single cosinor method, were not significantly different among the seasons. On the other hand, the acrophase of pulse rate appeared significantly later in winter (16:19) compared with those in spring (14:54), summer (14:42), and autumn (14:21). Urine volume and urinary excretion of norepinephrine were significantly greater in winter than in summer. These results indicate that the 24-h pattern of blood pressure is reproducible and shows no seasonal difference in young normotensive women.

[Relationship of dietary intake of sodium, potassium, calcium and magnesium to blood pressure]

Dietary intake of sodium (Na), potassium (K), calcium (Ca) and magnesium (Mg) from measured food intake, and urinary Na and K excretions estimated by analyzing the second voided morning urine were analyzed for correlations to each other and to blood pressure in 57 males and 90 females (average age of 53 years). Significant positive correlations were found between systolic blood pressure and urinary Na/K ratio, dietary Ca/Mg ratio and body mass index after adjustment for age. Diastolic blood pressure was also positively correlated to these variables. By multiple regression analysis, the coefficients for age and urinary Na/K and dietary Ca/Mg ratios were all statistically significantly associated with systolic and diastolic blood pressure. Dietary Ca/Mg ratio was negatively correlated with rice, beans and fish intake, and urinary K excretion positively correlated with fish and green vegetable intakes by the same analysis. These data suggest that the dietary Ca/Mg ratio--but not magnesium singly--as well as aging and urinary Na/K ratio were among important factors related to blood pressure.

A school refusal case with biological rhythm disturbance and melatonin therapy

An 18-year-old male high school student with school refusal and circadian rhythm disturbance is reported. At 17 years of age, he was unable to attend school because of a reversal of the daily rhythm and a moderate depressive feeling. Other circadian rhythms, including deep body temperature (DBT), and plasma melatonin, cortisol and beta-endorphin, also showed quite different or abnormal curves compared with those in normal controls. He was treated with methyl B12 and melatonin, which normalized the circadian rhythm, i.e. it became entrained to a 24-h period, and the DBT and hormonal rhythms became closer to normal patterns. These results suggest that desynchronization of the biorhythms, particularly the circadian rhythm, may be one of the important causes of school refusal in Japan, and melatonin and methyl B12 might be useful for treatment of the condition.

Blood pressure 24-hour pattern in two industrialized countries (Italy and Japan) with a different culture in salt intake

This study investigates the blood pressure (BP) 24-hour pattern in representative samples of 2 industrialized countries, Italy and Japan, showing different cultures in salt intake. BP was monitored by means of a noninvasive ambulatory device whose readings were analyzed by means of chronobiometric procedures. The results show that the 24-hour BP pattern is not substantially different in Italian and Japanese subjects. In particular, the expected lower BP in the Italians was not detected despite their lower salt intake. Because the 24-hour mean BP value was seen not to be proportional to salt intake, the hypothesis is formulated that maintenance of the pressure regimen within a given range of variability is a principle of human physiology. To comply with this rule the Japanese people are supposed to have ethnically developed a certain resistance to dietary salt for which their cardiovascular apparatus is protected (phyletic escape to dietary sodium excess).

Investigation of high salt intake in a Nepalese population with low blood pressure

The relation between BP and the factors influencing an increase in BP with age were investigated in the inhabitants of two representative hilly (Kotyang: 206 men and 212 women) and suburban (Bhadrakali: 265 and 244) villages in Nepal. BP for both sexes was statistically significantly higher in Bhadrakali than in Kotyang. Neither hypertension nor elevation of BP with age for men and very few women (1.4%) with hypertension were observed in Kotyang, while 10.9% of men and 4.9% of women were found to be hypertensive in Bhadrakali. Average urinary Na excretion was 183-221 mEq/day in both villages. Urinary Na/K ratio, percentage body fat (%Fat), total protein, total cholesterol and serum Ca were statistically significantly higher in Bhadrakali than in Kotyang, and maximal oxygen uptake and serum Mg were higher in Kotyang. In spite of high salt consumption, there was no increase in BP with age in Kotyang's males, suggesting that the BP may be influenced by physical activity, fat-free mass and nutrient consumption in addition to the high sodium intake, and that extremely high physical activity and very low %Fat could serve to mute the influence of high sodium intake.

Relationship between total serum cholesterol level and nutritional and physical status in Nepalese rural people

To investigate the nutritional condition in a hilly village (Kotyang) and a suburban village (Bhadrakali) in Nepal and to clarify the possible cause of the difference in total serum cholesterol level between the two groups of villagers habitually eating low fat diets, we carried out a nutrition survey using the 24-h recall method and blood sampling in 403 subjects (204 men and 199 women) in the hilly village and 466 (244 men and 222 women) in the suburban village. Total serum cholesterol was statistically significantly lower in the hilly villagers than in the suburban villagers for both sexes, but HDL-cholesterol was not. In both villages, 82% of the total energy was taken from carbohydrate, 7-8% from fat and 10% from protein. Energy, protein, fiber, potassium, magnesium, monounsaturated fatty acid, polyunsaturated fatty acid, and vitamin A in the hilly villagers were significantly higher than those in the suburban villagers. Total serum cholesterol was significantly associated with age and body fat percentage, suggesting that total serum cholesterol level was not directly associated with total fat intake in these Nepalese people.

A simple method for estimating 24 h urinary sodium and potassium excretion from second morning voiding urine specimen in adults

1. An assessment was made of the extent sodium (Na) and potassium (K) intake can be estimated from Na, K and creatinine (Cr) content of a second morning voiding urine (SMU) specimen collected within 4 h after the first voiding upon awakening but before breakfast in 159 clinically healthy, free-living individuals (20-79 years). The SMU and the rest of 24 h urine specimens for a 3-5 day period were collected. 2. The following equations for estimating 24 h urinary Na (24HUNaV) and K (24HUKV) excretions were developed, and the accuracy and the reliability of these equations were evaluated. Estimated value of 24HUNaV (mEq/day) = 16.3 square root of XNa; estimated value of 24HUKV (mEq/day) = 7.2 square root of XK, where XNa (or XK) = SMUNa (or SMUK)/SMUCr x predicted 24 h urinary Cr excretion. 3. Highly statistically significant correlations were detected between the values estimated and measured for both Na (r = 0.728, P < 0.001, n = 159) and K (r = 0.780, P < 0.001, n = 159). 4. These equations were applied to Group 1 subjects, who collected the urine for a single day, and to Group 2, for 3 days. The correlation coefficients between the values estimated and measured for Na and K were 0.531 and 0.443 in Group 1, and 0.821 and 0.590 in Group 2, respectively. No statistically significant differences were observed. 5. The SMU specimens provide a satisfactory alternative to both 24HUNaV and 24HUKV in adults for extensive epidemiological surveys but also for clinical application.

Pre-Cushing's syndrome: a case report

A 67-year-old man affected by prostate cancer was incidentally found to have a nodular enlargement of the left adrenal gland without apparent changes in hormonal status. The adrenal mass was found to be scintigraphically active, the radiolabelled compound being concentrated in its context with a consensual suppression of the contralateral uptake. The patient underwent a resection of the adrenal tumor. Histologically and biochemically, the adrenal mass was found to be a non-functioning adenoma. The radioisotopic uptake along with the non-hormonal activity prompted us to call this tumor "Pre-Cushing's syndrome" of the adrenal cortex.

[Prediction of 24-hour urinary creatinine excretion from age, body weight and height of an individual and its application]

Equations to predict 24-hour urinary creatinine excretion (UcrV) from age, body weight (W) and body height (H) were developed based on the data for UcrV determined by collecting 24-hour urine for 3-5 days in 256 male and 231 female clinically healthy subjects, aged from 20 to 84 years. By regression analysis a regression equation was developed. Multiple regression analysis revealed that age, W and H contributed most to the measured value of UcrV. The regression equations to predict UcrV from age, W and H were as follows: Predicted value of UcrV (PRCr) = -12.63 x Age + 15.12 x W + 7.39 x H - 79.90 (male: mg/day) PRCr = -4.72 x Age + 8.58 x W + 5.09 x H - 74.50 (female: mg/day) The multiple correlation coefficients were 0.87 for males and 0.73 for females, respectively. The difference between PRCr and measured UcrV (residual) was +0.81 +/- 154 (SD) mg/day on the average. An analysis of residuals by means of plotting of standardized residuals and predicted standardized dependent variables showed no remarkable deviations in both sexes, suggesting that these equations are applicable to the prediction of UcrV. These equations were applied to 38 Japanese men and women who were asked to collect 24-hour urine for 14 days on average, and also to 47 foreigners (American, Nepalese and Italian). The average residual in the former was +27 +/- 87 mg/day and that in the latter -3 +/- 85 mg/day, suggesting that these equations can be applied not only to the Japanese but also to the foreigners as a useful index in predicting 24-hour urinary creatinine excretion.

Circadian variations of total renin, active renin, plasma renin activity and plasma aldosterone in clinically healthy young subjects

The direct assay of total renin (TRC) and active renin concentration (ARC) is a reality due to the availability of monoclonal antibodies against human renin. Because of this, a study has been performed in order to assess the circadian rhythmicity of TRC and ARC. The study was extended to plasma renin activity (PRA) and plasma aldosterone concentration (PAC) for a more complete assessment of the renin-angiotensin-aldosterone system (RAAS). Twelve clinically healthy subjects (6 males and 6 females, age from 20 to 25 years) volunteered for this study. Time-qualified data series were analysed by means of chronobiological procedures in order to validate the circadian rhythm and to correlate the sinusoidal profiles. The circadian rhythm was validated at a high significance for TRC, ARC, PRA and at a borderline significance for PAC. The periodic oscillations were significantly correlated, demonstrating that TRC, ARC, PRA and PAC cycles oscillate in synchronism during the 24-hour span.

Gender, age and circadian blood pressure variation of apparently healthy rural vs metropolitan Japanese

Interim chronobiologic cardiovascular reference data have been described; 353 clinically healthy Japanese subjects were monitored every 15 min for 24h on 2 occasions. Special attention was paid to the difference between metropolitan and rural areas. Not only the MESORs of SBP and DBP, but also the circadian amplitudes, were higher in the Tokyo than in a rural area (Komaki, Aichi Prefecture). Age-related alterations in the circadian profile of cardiovascular variables were noted for women but not for men. The average MESOR remained similar for SBP in men, whereas in women the average MESOR increased with advancing age in both urban and rural areas. The average circadian amplitude of SBP also increased with age in women, but not in men. No significant deviations of acrophase with age were found for SBP and DBP in men, whereas in rural women the acrophase tended to occur earlier with increasing age.

[A comparative study of % fat and living style on nepalese]

Measurements of %Fat, nutrient intake and maximal aerobic power (MAP) were carried out on Nepalese to clarify the cause of obesity attended with modernization. One hundred thirty-two males (KV) who have a natural living style, 20-84 years of age, in rural district and 237 males who have a living style affected by the rapid urbanization, in surburban district were selected as subjects. The subjects of surburban district were divided into two groups. One of them included 147 farmers (BF) who engage in not mechanized farming, 20-73 years of age. Another group included 90 students and wage laborers (BNF) who go to and from Kathmandu (the capital of Nepal), 20-57 years of age. %Fat was estimated from skinfold thickness according to the method of Nagamine (1975). The survey for the nutrient intake was carried out by the 24-hour recall method to obtain the individual food consumption using the food models. Measurement of MAP was made indirectly by the modified of Margaria et al (1965). The main results are summarized as follows. 1) Mean %Fat and the appearance rates of obesity in each age group showed high values in following order: BNF greater than BF greater than KV. 2) Mean caloric intake in KV was higher than those in BF and in BNF an almost all age groups and no significant difference was found between BF and BNF in all age groups. 3) No significant differences in mean fat intake and in mean animal fat intake among all groups were found in almost all age groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Circadian variations of urinary dopamine, norepinephrine, epinephrine and sodium in normotensive and hypertensive subjects

Under standardized conditions, we determined circadian urinary excretion of sodium (Na) and free dopamine (DA), norepinephrine (NE) and epinephrine (E) in 20 normotensive, 20 borderline hypertensive and 10 mild hypertensive middle-aged men. The 24-hour excretions of water, Na, DA, NE and E were comparable between the normotensives and the hypertensives. In the total study population, these parameters showed significant time-related changes: high excretion during the daytime and low excretion in the night. The circadian variations of urinary DA, NE and E were similar among the 3 groups. The circadian curve of urinary DA was similar to those of Na and water excretion. In the total study population, 24-hour water and Na excretion correlated positively with urinary DA, but not with NE or E. These results suggest that endogenous DA may play a role in the circadian variation of water and sodium metabolism. The circadian excretion of urinary catecholamines may not be altered in middle-aged subjects with borderline or mild hypertension.

Preventive distinction of patients with primary or secondary hypertension by discriminant analysis of chronobiologic parameters estimated on 24-hour blood pressure patterns

This investigation deals with a statistical probatory that patients with primary (PH) or secondary (SH) hypertension may be correctly diagnosed by a discriminant analysis of the chronobiologic characteristics computed on the 24-hour blood pressure (BP) patterns. The methodology concerning non-invasive 24-h BP monitoring, chronobiologic analysis and the discrimination process is detailed. Substantial dissimilarities were found in the statistical distribution for systolic and diastolic BP rhythmometric parameters (mesor, amplitude and acrophase) by a retrospective assessment of two groups, consisting of 54 patients with PH and 16 patients with SH. The group-related distribution for rhythmometric parameters was found to be significantly different to generate a statistically significant intergroup discriminatory boundary. The discriminant analysis correctly diagnosed patients with PH and SH in a percentage of about 91% and 63%, respectively. The high incidence of success is convincing that the combination of 24-h BP monitoring/chronobiologic analysis/discrimination process cna be a practical tool for confidently selecting patients with a presumable PH or SH.

Circadian variations of plasma atrial natriuretic peptide in four types of hypertensive disorder during pregnancy

Circadian variations in plasma atrial natriuretic peptide were studied, to clarify the characteristic pathophysiology of pregnancy-induced hypertension (PIH). The mean 24-h values (range) of atrial natriuretic peptide in mild and severe PIH, pregnancy-aggravated hypertension, chronic hypertension and normal pregnancy were 130.1 (97.3-207.0), 225.4 (202.8-281.8), 213.1 (183.2-249.5), 81.3 (61.8-116.1) and 77.1 (56.0-123.5) pg/ml, respectively. The values in PIH and pregnancy-aggravated hypertension were significantly higher, although those in chronic hypertension were no different from normal pregnancy. Plasma atrial natriuretic peptide showed a clear circadian rhythm with acrophase in the middle of the night, in mild and severe PIH. In the other hypertensive disorders, a circadian rhythm could not be confirmed. The results indicate that the elevated values of plasma atrial natriuretic peptide in hypertensive disorders during pregnancy relate to generalized vasoconstriction, and that the diurnal rhythm is a specific characteristic of PIH.

"GIANT" macronodular adrenal hyperplasia causing Cushing's syndrome: case report and review of the literature on a clinical distinction of adrenocortical nodular pathology associated with hypercortisolism

Cushing's syndrome (CS) may be sustained by a nodular adrenocortical pathology (NAP) in addition to hyperplastic or neoplastic lesions of adrenal glands. NAP, in turn, may be represented by macronodular (MACRO) or micronodular (MICRO) manifestations. There is debate as to whether the MACRO-NAP and MICRO-NAP represent an expression of the same disorder or relate to distinguishable anatomo-clinical entities. A case of CS sustained by a "giant" MACRO-NAP forced use to review the literature and to analyze the morpho-clinical findings from a statistical viewpoint. Testing procedures were able to significantly dissect some clinical, pathological and hormonal characteristics. The statistical probation clearly indicated that MACRO-NAP and MICRO-NAP causing CS are nosologic entities that can be clinically differentiated via their phenotypic symptomatology.

Sympathetic response to oral glucose load is altered in hypertensive subjects

Blood pressure, plasma norepinephrine (NE) and epinephrine (E) levels in responses to oral glucose load (OGTT) and to head-up tilting (Tilt) were measured in 14 hypertensive (HT) and 17 normotensive subjects (NT). In response to OGTT, NE significantly increased within 30 minutes (+25 +/- 8%; p less than 0.05) in NT, followed by a decline to the basal level, while it remained unchanged in HT (+5 +/- 8%). E decreased similarly during OGTT in both groups. Mean blood pressure, however, fell only in HT (-3.3 +/- 1.1%; p less than 0.05) but did not change in NT. Blood pressure, NE and E responses to Tilt did not differ between NT and HT. These results suggest that hypertensive subjects have some defects in sympathetic activation in response to glucose loading.

Long-term prognosis of malignant hypertension; difference between underlying diseases such as essential hypertension and chronic glomerulonephritis

A long-term prognosis was studied in 69 patients with malignant hypertension, followed for an average of 56 months. Overall survival rate was 90% for a 5-year period, although the prognosis was different between two major underlying diseases, namely the 5-year survival was 79% for 33 essential hypertension (EHT) and 100% for 26 chronic glomerulonephritis (CGN); the difference is significant (p less than 0.01). In contrast, the 5-year rate for renal survival, defined as the probability of surviving without hemodialysis, was 37% in all cases. However, there was significant difference in the renal survival between EHT (60% for a 5-year period) and CGN (4% for a 18-month period). Multivariate analyses of the Cox's proportional hazards model revealed that the long-term change in renal function was different between the two groups, namely more rapid deterioration in the CGN group. These results indicate that a long-term prognosis of malignant hypertension is influenced by the underlying diseases and hemodialysis besides antihypertensive treatment may increase survival in malignant hypertension associated with severely damaged renal function.

Pathophysiology in malignant hypertension: with special reference to the renin-angiotensin system

Pathophysiology of malignant hypertension, of which underlying disease was essential hypertension (EHT) in 33 cases and chronic glomerulonephritis (CGN) in 26 cases, was studied with reference to the renin-angiotensin system. Plasma renin activity (PRA) was significantly higher in the EHT than in the CGN group, and angiotensin II antagonist [Sar1, Ile8]angiotensin II (AIIA) induced a significant lowering of blood pressure only in the former group. PRA was linearly correlated with both pretreatment mean blood pressure (MBP, r = 0.474, n = 29, p less than 0.01) and serum creatinine (r = 0.540, n = 29, p less than 0.01) in the EHT group but not in CGN patients, although there was an inverse correlation between PRA and serum sodium in both groups. Multiple regression analysis revealed that PRA was independently related to MBP, serum creatinine, and serum sodium in the EHT group, but not in the CGN group. These results suggest that the renin-angiotensin system plays a significant role in elevating blood pressure and deteriorating renal function in malignant hypertension derived from EHT, but it is less important in CGN related hypertension.

Is single oral administration of captopril beneficial in screening for primary aldosteronism?

Plasma renin activity (PRA) and plasma aldosterone concentration (PAC) were measured in 19 cases with primary aldosteronism (PA) and in 72 with essential hypertension (EHT) to differentiate the two disorders during the following conditions on normal salt diet: after overnight recumbency (basal state) and 2 hours after oral administration of 25 mg of captopril. Screening criteria were determined so that all PA patients were diagnosed as positive, and their specificities were compared with those of other conventional screening methods for PA. After captopril administration, the specificity of a criterion based on a combination of PAC and PAC/PRA ratio was 93% and positive predictive value was 79%. This criterion was superior to blood pressure response to angiotension II analog infusion, PRA on salt depletion, and to PAC on salt loading. However, higher specificity (97%) and positive predictive value (90%) were obtained from a criterion based on a combination of basal PAC and PAC/PRA ratio. Therefore, the use of a combination criterion based on PAC and PAC/PRA ratio at basal state rather than after captopril administration may give a satisfactory result in the screening for PA.

Circadian characteristics of urinary epinephrine and norepinephrine from healthy young women in Japan and U.S.A

Clinically healthy diurnally active young adult women were studied during the same season (March) at the Universities of Kyushu (Fukuoka City, Japan) and of Minnesota (Minneapolis, U.S.A.), under comparable conditions, except that the habitual diets were not changed. The subjects (20 Japanese and 16 Americans of mixed Caucasian background) were studied over a single 24-hr span. Urine was collected at 4-hr intervals. A circadian rhythm in total urinary norepinephrine excretion showed similar characteristics in Japanese and Americans. In epinephrine excretion, the Japanese women showed a statistically significantly higher amplitude with higher peak values, but no statistically significant difference in the rhythm-adjusted mean. This intergroup difference is strictly time dependent; it does not come to the fore in urine samples covering the nocturnal rest span of the subjects.

[Plasma aldosterone concentration in patients with primary aldosteronism in the last decade]

We analyzed the chronological variation of plasma aldosterone concentration (PAC) in 27 surgically confirmed patients with primary aldosteronism (PA) during the period from 1975 to 1984. PAC values in PA-patients were significantly higher than those in 82 age-matched patients with essential hypertension (EHT). However, although average PAC in the PA-patients declined consistently in recent years, no chronological trend of PAC was observed in the EHT-patients. Therefore, the distributions of PAC in the two groups of patients overlapped in the last few years. Such chronological variations of PAC in the PA-patients were not related to serum potassium concentration, blood pressure level on admission, duration of hypertension, or diameter of the adrenal adenomas. In some recently observed cases of PA, not only was the basal PAC relatively low, PAC also responded to either salt depletion or salt loading. These findings could not be explained simply by the change of methodology for PAC determination but rather by the technological advance of diagnostic radiology. As a result, PA might be diagnosed in the early stages or before becoming fullblown. Further study should be necessary to clarify the exact mechanism.

The renin-angiotensin-aldosterone system and circadian rhythm of urine variables in normotensive and hypertensive subjects

Forty-two middle-age male subjects, aged from 47 to 54 years old, were divided into three groups; 14 normotensives (NT), 16 borderline hypertensives (BHT) and 12 hypertensives (HT). The environmental effects were neutralized as much as possible by keeping their activities synchronized and their plasma and urine variables simultaneously investigated using the same protocol as under normal physiologic conditions. The circadian rhythms of urinary excretions of Na, K, Cl, creatinine, aldosterone, adrenaline and noradrenaline were analyzed by a multivariate method (cosinor method). Both systolic and diastolic blood pressure were statistically significantly different among the three groups and body weight was greater in HT than in NT. Other plasma and urine variables examined, however, were not significantly different among the three groups. A statistically significant circadian rhythm was detected in the urine variables. The rhythm characteristics, such as the mesor, amplitude and acrophase, of the urine variables except for the acrophase of urinary Na excretion were not significantly different among the three groups; the circadian acrophase of urinary Na in HT and BHT appeared significantly earlier than in NT. The pathophysiological and clinical significance of the earlier appearance of the circadian acrophase of urinary Na in hypertensive subjects still remains a unique characteristic requiring further investigation.

Relationship of urinary kallikrein excretion to renal water and sodium excretion

The circadian rhythms of urine volume and urinary excretion of sodium, potassium, kallikrein, and aldosterone were analyzed by a multivariate method (cosinor method) in 20 healthy Japanese women on an ordinary diet. The relationship of urinary kallikrein and aldosterone excretion to urine volume and urinary sodium and potassium excretion was studied by assessing the correlation of the circadian rhythms. The acrophases in the circadian rhythms of urine volume (16:51) and urinary sodium excretion (16:55) appeared after the acrophase of urinary kallikrein excretion (15:28). There was a highly significant correlation between the circadian rhythm of urinary kallikrein excretion and the circadian rhythms of urine volume (r = 0.948) and urinary sodium excretion (r = 0.921). These results suggest that the renal kallikrein-kinin system participates in the regulation of renal water and sodium excretion in persons on an ordinary diet. A highly significant relationship between the acrophases in the circadian rhythms of urine volume and sodium excretion (r = 0.935) also suggests that water and sodium excretion may have a mutual influence on the kidneys. There were positive correlations between the circadian rhythms of potassium excretion and kallikrein excretion and potassium excretion and sodium excretion; and the latter relationship was relatively closer than the former. The acrophase in the circadian rhythm of aldosterone excretion did not correlate well with the acrophases of the other urine variables including sodium excretion.

Comparison of circadian rhythms of the renin-angiotensin-aldosterone system and electrolytes in clinically healthy young women in Fukuoka (Japan) and Minnesota (USA)

Circadian rhythms of the renin-angiotensin-aldosterone (R-A-A) system and electrolytes were evaluated in young healthy Fukuokan (Japan) and Minnesotan (USA) women. A similar protocol was used and each group remained on its usual diet. Blood was taken for 24 h at 4 h intervals from 8 a.m. during which time urine samples were also collected. The determinations in both groups were made in a laboratory in Japan. Plasma renin activity, plasma aldosterone concentration and aldosterone excretion rate showed similar circadian rhythms in both groups. However, those values at each sampling time and each span were always significantly higher in the Americans while the urinary Na and Cl excretions and blood pressure were higher in Japanese. The significant differences in the R-A-A system and blood pressure levels between these two groups may be due to the large amount of salt consumed by the Japanese.

Average urinary excretion of sodium in 24 hours can be estimated from a spot-urine specimen

We assessed to what extent sodium intake can be estimated from the sodium content of a spot-urine specimen (spot-UNa) collected within 4 hours after the first voiding upon awakening but before breakfast. Subjects were asked to collect spot-urine and 24-hour urine specimens other than the spot-urine for a 3-day period, either successively or intermittently. The coefficient of correlation between spot-UNa and urinary excretion of sodium in 24 hours (24-h UNa) collected on the first day was 0.47. When the coefficient of the variation of creatinine excretion in the spot-urine was above 20%, the sample was discarded as the "outlier', and in this case the coefficient of correlation was 0.725. A marked fluctuation of creatinine excretion in spot-urine was considered to represent technical errors at the time of the spot-urine collection. The coefficient of variation of intra-individual 24-h UNa exceeded 20%, suggesting that a single determination of 24-h UNa does not represent the individual average of daily urinary excretion of sodium. It is concluded that the determination of a substantial number of spot-urine specimens to estimate daily salt ingestion of a given subject may be more reliable than a single determination of 24-h UNa, if the "outlier' of creatinine excretion in spot-urine specimen is excluded from the determination of spot-UNa. The average urinary excretion of sodium in 24 hours by the Japanese subjects investigated here was 218 +/- 67 mEq.

[Plasma cortisol concentrations and circadian rhythm in healthy young Japanese and caucasians (author's transl)]

We report herein a method of solid-phase radioimmunoassay (RIA) for assessment of plasma cortisol concentration using 125I-labeled ligand [CORTCTK-125]. Plasma cortisol concentrations and its circadian rhythm in healthy young Japanese and American whie women were also evaluated using CORTCTK-125. Nineteen Japanese women, of an average age of 20.3 +/- 0.1 years, and 12 Caucasians of mixed ethnic origin (Minnesota), average 20.0 +/- 0.5 years, were studied using a similar protocol. The distribution of the menstrual stage of the two groups was similar. Blood was drawn from each subject into EDTA containers at 4-hour intervals starting at 0800 on one day and was continued for the ensuing 24 hours. The samples were immediately placed in a refrigerated centrifuge at 4 degrees C, and then stored at -20 degrees C until the assay. The samples from Minnesota were packed in dry ice and brought by air to Japan. Determinations of plasma cortisol concentration in samples from both groups were carried out at Kyushu University. Advantages of the solid-phase RIA method are as follows: (1) 0.05 ml of plasma or serum was sufficient for determination of plasma cortisol concentrations, (2) no other solvents or solutions for the extraction or purification were required, (3) the procedure was simple and readily facilitated, and (4) the concentration of cortisol in heparin-plasma was somewhat higher than that in serum or EDTA-plasma, but there was no statistical difference. Plasma cortisol concentrations in the samples from the Japanese (19.73 +/- 1.44 on the first and 18.94 +/- 1.32 microgram/dl on the second day) and that of the American group (17.48 +/- 2.38 and 19.37 +/- 2.16 microgram/dl, respectively) at 0800 was similar. The average value of 7 determinations at 4-hour intervals was 11.01 +/- 2.00 microgram/dl in the Japanese and 10.29 +/- 1.05 microgram/dl in the American group. A remarkable and similar circadian rhythm was observed in both groups with a peak at 0800 and with nadirs at 2000 in the Japanese (4.80 +/- 0.45 microgram/dl) and 2400 in the American group (5.18 +/- 0.83 microgram/dl). There were statistically significant differences between the values at the peak and the nadir. The related subjects were then classified into Group-F (9 subjects) and Group-T (9); the former included high body mass index [BMI: body weight(kg)/body height(m)2] of more than 24.0, and the latter included a relatively lower BMI of less than 21.5. The circadian rhythm of both groups revealed a similar pattern, whereas plasma cortisol concentration was always higher in Group-F than in Group-T, at all 7 determinations. There were no significant differences except for the value at 0400. Furthermore, the average values of plasma cortisol concentration and circadian rhythm were compared; the group with a larger body surface area (BSA) (Group-L) and the group with a smaller BSA (Group-S). No difference was found in the plasma cortisol concentration of Group-L and -S, and the circadian rhythm was similar in both groups...