Circadian Blood Pressure Rhythm in Primary and Secondary Hypertension

Circadian blood pressure variability was recorded in patients with primary hypertension and with different forms of secondary hypertension using ambulatory 24-h blood pressure measurement. A group of 20 patients with different forms of secondary hypertension was compared with a matched group of patients with primary hypertension. Although the mean 24-h blood pressure was not different between the two groups, the patients with secondary hypertension had significantly higher systolic blood pressure during sleep and higher systolic and diastolic blood pressure in the early morning, compared with the primary hypertension group. This nocturnal blood pressure fall was then investigated in various groups of patients with different forms of secondary hypertension and compared with normotensives and patients with primary hypertension. Patients with mild primary hypertension (n = 152) and with severe primary hypertension (n = 30) had the same blood pressure fall (14–16 mm Hg systolic and diastolic) during the night (23:OO–05:OO h) as normotensives (n = 20). However, in patients with renoparenchymal hypertension (n = 29), renovascular hypertension (n = 20), hyperaldosteronism (n = 6), and hyperthyroidism (n = 14), the nocturnal blood pressure fall was significantly (p < 0.01) reduced. One patient with coarctation ofthe aorta and nine patients with primary hyperparathyroidism and elevated blood pressure had a normal circadian blood pressure profile with a normal nocturnal blood pressure fall. The heart rate decrease during the night was equal in all patient groups. Ambulatory blood pressure measurement allows blood pressure recording under everyday conditions, including nighttime. In primary hypertension the blood pressure variability exhibits the same circadian variation as in normotension, showing a marked nocturnal fall. However, in different forms of secondary hypertension, blood pressure shows a blunted circadian curve. This could have important diagnostic and therapeutic implications.     

Nocturnal blood pressure in normotensive subjects and those with white coat,primary, and secondary hypertension.

OBJECTIVE--To compare the mean nocturnal blood pressure of patients with various forms of renal and endocrine hypertension with that in patients with primary and white coat hypertension, and normal blood pressure. DESIGN--Ambulatory monitoring of blood pressure over 24 hours in a prospective study. SETTING--Two German centres for outpatients with hypertension and kidney diseases. SUBJECTS--176 normotensive subjects, 490 patients with primary hypertension including mild and severe forms, 42 with white coat hypertension, 208 patients with renal and renovascular hypertension, 43 with hypertension and endocrine disorders, and three with coarctation of the aorta. MAIN OUTCOME MEASURES--Fall in nocturnal blood pressure. RESULTS--Blood pressure in normotensive subjects fell by a mean of 14 mm Hg (11%) systolic and 13 mm Hg (17%) diastolic overnight (2200 to 0600). The falls in patients with primary and white coat hypertension were not significantly different. In all patients with renal and renovascular hypertension, however, the fall was significantly reduced (range of fall from 3/3 mm Hg to 7/9 mm Hg). In patients with hypertension and endocrine disorders the pattern of night time blood pressure was not uniform: patients with hyperthyroidism, primary hyperaldosteronism, and Cushing''s syndrome had significantly smaller reductions in blood pressure (6/8, 4/7, 3/6 mm Hg, respectively). In patients with phaeochromocytoma the mean night time blood pressure increased by 4/2 mm Hg. In patients with hypertension, primary hyperparathyroidism, and unoperated coarctation of the aorta the falls in blood pressure were normal. CONCLUSIONS--In normotensive subjects and those with primary hypertension there is usually a reduction in blood pressure at night. In all renal forms of secondary hypertension and in most endocrine forms the reduction in blood pressure is only a third to a half of normal. Patients with primary hyperparathyroidism and unoperated coarctation of the aorta show a normal reduction.     

Circadian Rhythm of Blood Pressure and Heart Rate in Healthy Persons and Kidney Transplant Patients: Correlations with Activity

Fourteen diurnally active (07: 00–22: 39 h) normotensive healthy control subjects and 14 kidney transplant patients were studied by ambulatory blood pressure monitoring and wrist actigraphy simultaneously during one 24-h period. In the control group, circadian rhythms in systolic (SBP), diastolic (DBP), and mean arterial (MAP) blood pressure, heart rate (HR), and wrist activity were documented by cosinor analysis with comparable afternoon peak times. In contrast, circadian rhythms with afternoon acrophases were detected only in HR and wrist activity in the patient group. The correlation of wrist activity with HR in controls and patients was comparable. Wrist activity and blood pressure were associated (r = 0.65 DBP and 0.54 SBP; p < 0.05) in controls, while in patients the relationship was weak or absent (r ranging from 0.02 SBP to 0.22 DBP). In 6 of 14 patients, BP and wrist activity were negatively correlated, reflecting the existence of nocturnal hypertension. In eight others, the correlation was small but positive. The 24-h pattern in BP and wrist activity in controls was comparably phased; however, this was not the case for the transplant patients, indicating the day-night pattern in blood pressure in this group is strongly dependent on pathologic phenomena rather than activity level and pattern.     

Twenty-Four hour blood pressure profile in subjects with different subtypes of primary aldosteronism

The aim of our study was to evaluate the potential differences in blood pressure (BP) profile in subjects with different forms of primary aldosteronism (PA). Simultaneously, we studied the effects of PA treatment on BP curve. We therefore monitored 24-hour ambulatory blood pressure values in 22 subjects with aldosterone-producing adenoma (APA), 22 subjects with idiopathic hyperaldosteronism (IHA) and 33 subjects with essential hypertension (EH) as controls. We found a significantly attenuated nighttime systolic BP decline in the APA group (P=0.02). Patients with IHA had lower nighttime systolic BP values (P=0.01) and also a diastolic BP decline (P=0.02) during the night in comparison with EH. We did not detect any significant differences in BP profile characteristics between APA and IHA. Specific treatment of primary aldosteronism (adrenalectomy, treatment with spironolactone) led to the normalization of the BP curve with a marked BP decline. Our study thus demonstrates a blunted diurnal BP variability in patients with primary aldosteronism the specific treatment of which normalized previously attenuated nocturnal BP fall.     

低钠透析联合血液透析滤过对终末期肾脏病合并顽固性高血压患者血压节律、钙磷代谢的影响

目的:探讨低钠血液透析(hemodialysis,HD)联合血液透析滤过(Hemodiafiltration,HDF)对终末期肾脏病合并顽固性高血压的透析患者血压节律、钙磷代谢的影响。方法:将62例终末期肾脏病合并顽固性高血压患者随机分为治疗组和对照组,对照组应用常规HD治疗,每周3次,每次4 h,治疗组低钠联合HDF治疗,每周1次,3个月后进行效果评价。比较两组治疗前后血压昼夜节律、钙磷代谢变化及不良反应的发生情况。结果:治疗后,治疗组24 h收缩压(systolic blood pressure,24h SBP)、24 h舒张压(diastolic blood pressure,24h DBP)、日间收缩压(day systolic blood pressure,dSBP)、日间舒张压(day diastolic blood pressure,dSBP)、夜间收缩压(night systolic blood pressure,nSBP)、夜间舒张压(night diastolic blood pressure,nSBP)均较治疗前明显下降,且明显低于对照组(P0.05);对照组除nSBP外,其余血压指标治疗前后比较差异均无统计学意义(P0.05)。治疗后,治疗组血Ca水平较治疗前明显升高,且显著高于对照组,而血P、PTH水平较治疗前明显降低,且均明显低于对照组(P0.05)。治疗组和对照组不良反应发生率分别为16.1%、12.9%,两组比较差异无统计学意义(P0.05)。结论:低钠HD联合HDF治疗终末期肾脏病合并顽固性高血压患者可有效改善钙磷代谢并促进血压节律恢复。     

Chronopharmacology of Captopril plus Hydrochlorothiazide in Hypertension: Morning Versus Evening Dosing

Blood pressure follows a strong circadian rhythm in normotensive people and in patients with primary hypertension. This may have several implications for antihypertensive therapy, including the time of dosing. For this reason we studied the influence of different dosing times on the antihypertensive effect over 24 h using ambulatory blood pressure monitoring (ABPM). We studied 13 male patients with moderate hypertension with controlled blood pressure over 12 months under a fixed combination of captopril and hydrochlorothiazide. The dosage of the combination therapy was then halved and given as one evening and then as one morning dose, each for 3 weeks. The combination therapy given twice daily showed a good 24-h antihypertensive effect after 12 months of treatment. During the following 6 weeks the mean 24-h blood pressure did not increase under half dosage, irrespective of whether under evening or morning dosing. However, mean daytime values (systolic and diastolic) of ABPM were significantly higher with evening dosing when compared both with full dosage and with half dosage given in the morning. The mean arterial blood pressure over 24 h showed the same differences as systolic and diastolic blood pressure, whereas heart rate was not significantly different between the three therapeutic regimens. ABPM seems to be an ideal method for chronopharmacological investigations under everyday conditions. Our study demonstrated significant differences in daytime blood pressure but not in 24-h blood pressure between morning and evening dosing of a fixed antihypertensive combination therapy.     

Chronopharmacology of Captopril plus Hydrochlorothiazide in Hypertension: Morning Versus Evening Dosing

Blood pressure follows a strong circadian rhythm in normotensive people and in patients with primary hypertension. This may have several implications for antihypertensive therapy, including the time of dosing. For this reason we studied the influence of different dosing times on the antihypertensive effect over 24 h using ambulatory blood pressure monitoring (ABPM). We studied 13 male patients with moderate hypertension with controlled blood pressure over 12 months under a fixed combination of captopril and hydrochlorothiazide. The dosage of the combination therapy was then halved and given as one evening and then as one morning dose, each for 3 weeks. The combination therapy given twice daily showed a good 24-h antihypertensive effect after 12 months of treatment. During the following 6 weeks the mean 24-h blood pressure did not increase under half dosage, irrespective of whether under evening or morning dosing. However, mean daytime values (systolic and diastolic) of ABPM were significantly higher with evening dosing when compared both with full dosage and with half dosage given in the morning. The mean arterial blood pressure over 24 h showed the same differences as systolic and diastolic blood pressure, whereas heart rate was not significantly different between the three therapeutic regimens. ABPM seems to be an ideal method for chronopharmacological investigations under everyday conditions. Our study demonstrated significant differences in daytime blood pressure but not in 24-h blood pressure between morning and evening dosing of a fixed antihypertensive combination therapy.     

Effect of imidapril in dipper and nondipper hypertensive patients: comparison between morning and evening administration

The purpose of the study was to identify differences in the patterns of efficacy and duration of effects of imidapril administered at different times of the day (morning versus evening) in dipper and nondipper hypertensive patients. Twenty patients with untreated hypertension were classified into two groups: dippers (n = 9) and nondippers (n = 11). Imidapril (10 mg) was given at 07:00 or 18:00 for 4 weeks in a crossover fashion. Blood pressure (BP) and heart rate (HR) were monitored before and after morning and evening treatment every 30 min for 48h by ambulatory BP monitoring (ABPM). In dipper hypertension, the mean 48h BP was reduced with both doses. The decrease in the diurnal BP was stronger when the drug was administered in the evening than morning, but without significant difference. In nondipper hypertension, the systolic BP decreased at night with both doses, but the extent of the nocturnal reduction in systolic BP was greater after morning therapy. There were no significant differences in the decrease in BP during the day or night between the morning and evening administrations. When imidapril was administered in the morning, its serum concentration reached a maximum at 16:00, and when the drug was administered in the evening, it reached a maximum at 6:00. In dipper hypertension, the time taken for the blood concentration of imidapril to reach a maximum changed depending on its time of administration, and the time when the maximum antihypertensive effect of the drug appeared was different. In nondipper hypertension, decreases in the BP were confirmed at night regardless of the time of administration; this might be caused by angiotensin converting enzyme (ACE) inhibitors effectively blocking the BP from increasing by activating the parasympathetic nervous system. Therefore, when assessing the effectiveness of antihypertensive agents, factors such as the various patterns of BP before therapy and administration time must be considered.     

24-hour profiles of blood pressure and heart rate in Cushing's syndrome: relationship between cortisol and cardiovascular rhythmicities

We monitored the circadian profiles of cortisol, systolic and diastolic blood pressure (SBP and DBP) and heart rate (HR) in 33 matched normotensive subjects, 32 patients with essential hypertension and 16 patients with Cushing's Syndrome (8 pituitary adenomas, 6 adrenal adenomas and 2 adrenal carcinomas). Each subject underwent serial blood drawings at 4-hr intervals along the 24-hr cycle. BP and HR were automatically recorded every 30 min. Data were analyzed by conventional statistics and by chronobiological procedures (cosinor rhythmometry). Both the control subjects and essential hypertensives showed a circadian profile of BP and HR characterized by a peak in the early afternoon and a clear nocturnal fall (rhythm detection: P less than 0.001). The rhythmicity of BP was disrupted in patients affected by Cushing's Syndrome, whereas the 24-hr oscillation of HR was preserved (P less than 0.001). Our data are compatible with the view that glucocorticoids are involved in the control of BP circadian rhythm, whereas HR is not under their control.     

Plasma melatonin concentrations in hypertensive patients with the dipping and non-dipping blood pressure profile

Some patients with hypertension exhibit disturbed circadian organization in the cardiovascular system. Hormone melatonin can synchronize circadian rhythms and its repeated administration can improve synchronization of rhythmicity in blood pressure (BP). In our study we measured endogenous melatonin production in patients with essential hypertension exhibiting a dipping and non-dipping BP profile. Blood pressure was monitored for at least 24-hr with an automatic ambulatory BP monitor and patients with no decline in BP were classified as non-dippers. Plasma melatonin was measured in the middle of the daytime and night-time by radioimmunoassay. As expected night-time systolic (P <0.05), diastolic (P <0.001) and mean arterial (P <0.001) BP was higher in non-dippers than in dippers. No significant difference was found between both groups in BP during the day. Mean melatonin concentrations were higher during the night than during the day in both dippers and non-dippers. When patients were divided into dippers and non-dippers on the basis of mean arterial or diastolic BP a lower ratio of night/day concentration was determined in non-dippers than in dippers. Our study showed a blunted night/day difference in plasma melatonin concentrations in hypertensive patients with the non-dipping profile in diastolic BP indicating disturbances in the circadian system of these patients.     

Blunting of circadian rhythms and increased acrophase variability in sleep-time hypertensive subjects

24 h and ultradian rhythms of blood pressure (BP) have been previously shown to be disorganized in nocturnal hypertensive subjects. The present study was undertaken to further analyze the ultradian and circadian BP rhythm structure in sleep-time hypertensive subjects with normal or elevated awake-time BP levels. Fourier analysis was used to fit 24, 12, 8, and 6 h curves to mean BP as well as heart rate (HR) time series data derived from 24 h ambulatory blood pressure monitoring. Awake and sleep periods were defined according to individual sleep diaries. Awake-time hypertension was defined as diurnal systolic (SBP) and/or diastolic BP (DBP) means ≥135/85 mmHg. Sleep-time hypertension was defined as nocturnal SBP and/or DBP means ≥120/70 mmHg. The sample included 240 awake-time normotensive subjects (180 sleep-time normotensives and 60 sleep-time hypertensives) and 138 untreated awake-time hypertensive subjects (31 sleep-time normotensives and 107 sleep-time hypertensives). The amplitude and integrity (i.e., percent rhythm) of the 24 and 12 h BP rhythms were lower in the sleep-time hypertensive subjects and higher in the awake-time hypertensive subjects. However, no differences were detected when the integrity and amplitude of the 6 and 8 h mean BP rhythms were analyzed. The sleep-time hypertensive group showed significantly higher 24 h BP rhythm acrophase variability. No differences could be found in any of the HR rhythm parameters. Altogether, the findings suggest a disorganization of the BP circadian rhythm in sleep-time hypertensives that results in reduced 24 h rhythm amplitude and integrity that could be related to cardiovascular risk.     

24-Hour Profiles of Blood Pressure and Heart Rate in Cushing's Syndrome: Relationship Between Cortisol and Cardiovascular Rhythmicities

We monitored the circadian profiles of Cortisol, systolic and diastolic blood pressure (SBP and DBP) and heart rate (HR) in 33 matched normotensive subjects, 32 patients with essential hypertension and 16 patients with Cushing's Syndrome (8 pituitary adenomas, 6 adrenal adenomas and 2 adrenal carcinomas). Each subject underwent serial blood drawings at 4-hr intervals along the 24-hr cycle. BP and HR were automatically recorded every 30 min. Data were analyzed by conventional statistics and by chronobiological procedures (cosinor rhythmometry). Both the control subjects and essential hypertensives showed a circadian profile of BP and HR characterized by a peak in the early afternoon and a clear nocturnal fall (rhythm detection: P< 0.001). The rhythmicity of BP was disrupted in patients affected by Cushing's Syndrome, whereas the 24-hr oscillation of HR was preserved (P < 0.001). Our data are compatible with the view that glucocorticoids are involved in the control of BP circadian rhythm, whereas HR is not under their control.     

Administration time-dependent effects of valsartan on ambulatory blood pressure in elderly hypertensive subjects

Previous results have indicated that valsartan administration at bed-time, as opposed to upon wakening, improves the diurnal/nocturnal ratio of blood pressure (BP) toward a normal dipping pattern, without loss of 24 h efficacy. This ratio is characterized by a progressive decrease with aging. Accordingly, we investigated the administration time-dependent antihypertensive efficacy of valsartan, an angiotensin blocking agent, in elderly hypertensive patients. We studied 100 elderly patients with grade 1-2 essential hypertension (34 men and 66 women), 68.2+/-4.9 years of age, randomly assigned to receive valsartan (160 mg/d) as a monotherapy either upon awakening or at bed-time. BP was measured for 48 h by ambulatory monitoring, at 20 min intervals between 07:00 to 23:00 h and at 30 min intervals at night, before and after 3 months of therapy. Physical activity was simultaneously monitored every minute by wrist actigraphy to accurately determine the duration of sleep and wake spans to enable the accurate calculation of the diurnal and nocturnal means of BP for each subject. There was a highly significant BP reduction after 3 months of valsartan treatment (p < 0.001). The reduction was slightly larger with bed-time dosing (15.3 and 9.2 mm Hg reduction in the 24 h mean of systolic and diastolic BP, respectively) than with morning dosing (12.3 and 6.3 mm Hg reduction in the 24 h mean of systolic and diastolic BP, respectively). The diurnal/nocturnal ratio, measured as the nocturnal decline of BP relative to the diurnal mean, was unchanged in the group ingesting valsartan upon awakening (-1.0 and -0.3 for systolic and diastolic BP; p > 0.195). This ratio was significantly increased (6.6 and 5.4 for systolic and diastolic BP; p < 0.001) when valsartan was ingested at bed-time. The reduction of the nocturnal mean was doubled in the group ingesting valsartan at bed-time, as compared to the group ingesting it in the morning (p < 0.001). In elderly hypertensive patients, mainly characterized by a diminished nocturnal decline in BP, bed-time valsartan dosing is better than morning dosing since it improves efficacy during the nighttime sleep span, with the potential reduction in cardiovascular risk that has been associated with a normalized diurnal/nocturnal BP ratio.     

原发性高血压患者血压昼夜节律与靶器官损害的关系研究

目的:研究原发性高血压患者血压昼夜节律异常是否与靶器官损害存在关联。方法:将2015年2~11月份在我院治疗的94例原发性高血压病人按照血压昼夜节律是否正常分为节律正常组52例和异常组42例。比较两组患者的24h、白天、夜间的收缩压(SBP)与舒张压(DBP)及血压负荷,并且比较两组患者心脏、脑、肾损伤相关指标。结果:异常组全天24h、白天、夜间SBP及DBP,血压负荷均高于正常组,差异具有统计学意义(P0.05)。异常组患者左室重量(LVM)和左室重量指数(LVMI)、发生心肌缺血次数及持续时间、发生脑梗死几率均明显高于正常组,差异有统计学意义(P0.05)。异常组尿微量白蛋白(MAU)、尿酸(UA)水平均高于正常组,差异有统计学意义(P0.05)。结论:原发性高血压患者出现昼夜节律异常,可能对相关靶器官造成损伤。     

Nighttime Blood Pressure and White Matter Hyperintensities in Patients With Parkinson Disease

Increasing evidence indicates that nocturnal blood pressure level and/or loss of nocturnal blood pressure dips are sensitive markers of cardiovascular morbidity and mortality. Several studies have suggested that blunted heart rate variability and nocturnal decline in heart rate are also associated with target organ damage. These phenomena occur relatively commonly in patients with Parkinson disease (PD); however, few studies have assessed the consequences of these abnormalities in patients with PD. We investigated the influence of circadian changes in blood pressure and heart rate on white matter hyperintensities (WMHs) in patients with PD. The presence of nocturnal hypertension was associated with increased WMH score, and nighttime systolic pressure was closely related with white matter changes. Blunted heart rate variability and nocturnal decline in heart rate were also related to increasing WMH scores. The non-dipping phenomenon did not influence WMHs. These findings suggest that white matter changes are related to circadian autonomic dysfunction, particularly nocturnal hypertension in patients with PD. Therefore, it is important to monitor nocturnal blood pressure status, because modifying these circadian regulatory disturbances can be beneficial to protect against vascular brain damage in patients with PD. (Author correspondence: neuronet@catholic.ac.kr)     

Photic phase response curve in Octodon degus: assessment as a function of activity phase preference

Light exposure during the early and late subjective night generally phase delays and advances circadian rhythms, respectively. However, this generality was recently questioned in a photic entrainment study in Octodon degus. Because degus can invert their activity phase preference from diurnal to nocturnal as a function of activity level, assessment of phase preference is critical for computations of phase reference [circadian time (CT) 0] toward the development of a photic phase response curve. After determining activity phase preference in a 24-h light-dark cycle (LD 12:12), degus were released in constant darkness. In this study, diurnal (n = 5) and nocturnal (n = 7) degus were randomly subjected to 1-h light pulses (30-35 lx) at many circadian phases (CT 1-6: n = 7; CT 7-12: n = 8; CT 13-18: n = 8; and CT 19-24: n = 7). The circadian phase of body temperature (Tb) onset was defined as CT 12 in nocturnal animals. In diurnal animals, CT 0 was determined as Tb onset + 1 h. Light phase delayed and advanced circadian rhythms when delivered during the early (CT 13-16) and late (CT 20-23) subjective night, respectively. No significant phase shifts were observed during the middle of the subjective day (CT 3-10). Thus, regardless of activity phase preference, photic entrainment of the circadian pacemaker in Octodon degus is similar to most other diurnal and nocturnal species, suggesting that entrainment mechanisms do not determine overt diurnal and nocturnal behavior.     

Coronary flow reserve and the J curve relation between diastolic blood pressure and myocardial infarction.

The results of several large studies of hypertension and follow up studies on insured people have indicated that the lower the blood pressure the better for longevity. These studies excluded subjects with overt ischaemia. More recently long term studies of hypertension that included patients with more severe forms of hypertension and did not exclude those with overt ischaemia have shown a J shaped relation between diastolic blood pressure during treatment and myocardial infarction; the lowest point (the J point) was at a diastolic blood pressure (phase V) between 85 and 90 mm Hg. The J curve seems to be independent of treatment, pulse pressure, and the degree of fall in diastolic blood pressure and is unlikely to be caused by poor left ventricular function. The most probable explanation is that subjects who have severe stenosis of the coronary artery as well as hypertension have a poor coronary flow reserve, which makes the myocardium vulnerable to coronary perfusion pressures that are tolerated by patients without ischaemia, particularly at high heart rates. An optimal diastolic blood pressure (phase V) for such patients is about 85 mm Hg, though particular caution is appropriate when treating very old patients (84 and over) and patients aged 60-79 who have isolated systolic hypertension.     

Circadian rhythm of blood pressure in congestive heart failure and effects of ACE inhibitors.

In 33 patients with heart failure (NYHA II-III), the 24-h blood pressure rhythm was examined before and after the titration period of two ACE inhibitors. Blood pressure was measured by the oscillometric method using the blood pressure monitor 90202 from SpaceLabs, Inc. The measurements were taken from 06:00 to 22:00 h every 20 min and from 22:00 to 06:00 h every hour. Patients were randomized to therapy with either captopril (group 1, n = 17) or enalapril (group 2, n = 16). The average daily dosage of captopril was 41 +/- 3 mg given in three divided doses (08:00, 12:00, and 17:00 h). The mean dose of enalapril was 8 +/- 1 mg once daily (08:00 h). Serum electrolytes, serum creatinine, and plasma renin activity were measured before and during therapy with both ACE inhibitors. Twenty-four-hour blood pressure measurements were taken before and on the fifth day of treatment with ACE inhibitors. Both groups were not different with respect to the degree of heart failure, the concomitant medication, and the 24-h profiles of blood pressure and heart rate before initiation of ACE inhibition. The 24-h blood pressure values on day 5 were consistently below the pretreatment values (p less than 0.005) in both groups. Both groups did not differ significantly during ACE inhibition in their 24-h blood pressure and heart rate profiles. In both groups, the mesor of the systolic and diastolic blood pressure decreased significantly by the same degree (by 4.7/5.1 mmg Hg in group 1 and 6.4/4.1 mm Hg in group 2). The systolic/diastolic blood pressure amplitude decreased slightly in both groups. Before treatment, serum sodium, potassium, and creatinine were within the normal range. The increase in potassium (0.5 +/- 0.1 mmol/L) reached statistical significance (p less than 0.01) only in the captopril group, whereas it was not significant in the enalapril group (0.1 +/- 0.1 mmol/L). Serum creatinine was not significantly altered by both ACE inhibitors. No relationship could be found between the changes in serum potassium or creatinine and the mean of the 24-h blood pressure values during ACE inhibition. Captopril and enalapril showed comparable blood pressure profiles and similar effects on renal function at the end of the titration on day 5. It can therefore be concluded that the effects on blood pressure rhythm and renal function are similar with a single daily dose of enalapril compared to captopril given three times daily.     

贝那普利联合氨氯地平对高血压患者降压效果、血压变异性及心功能的影响

目的:探讨贝那普利联合氨氯地平对高血压患者降压效果、血压变异性(BPV)及心功能的影响。方法:选取2015年2月～2018年12月期间西安交通大学医学院附属三二〇一医院收治的131例高血压患者,根据随机数字表法分为对照组(n=65)和研究组(n=66),对照组患者给予氨氯地平治疗,研究组在对照组基础上联合贝那普利治疗。比较两组患者治疗后的降压效果、BPV以及心功能指标,记录两组患者治疗期间不良反应情况。结果:两组患者治疗4个月后收缩压(SBP)、舒张压(DBP)均下降,且研究组低于对照组(P0.05)。两组患者治疗4个月后24 h收缩压变异性(24hSBPV)、白天收缩压变异性(dSBPV)、24h舒张压变异性(24hDBPV)、白天舒张压变异性(dDBPV)均下降,且研究组低于对照组(P0.05),而夜间收缩压变异性(nSBPV)、夜间舒张压变异性(nDBPV)比较差异无统计学意义(P0.05)。两组患者治疗4个月后A峰速度、A/E峰值均下降,且研究组低于对照组(P0.05)。两组患者治疗4个月后E峰速度、EF值均升高,且研究组高于对照组(P0.05)。两组不良反应发生率比较无差异(P0.05)。结论:贝那普利联合氨氯地平治疗高血压患者的降压效果确切,可有效改善患者BPV及心功能,且安全性较好。     

Sleep and blood pressure.

Direct arterial pressure was recorded continuously over 24 hours in 18 totally unrestricted people (six normotensives, four untreated hypertensives, and eight treated hypertensives). There was an almost equal fall of about 20% in both systolic and diastolic blood pressure during sleep in the three groups when compared with their waking pressures. This fall in pressure was greater than that observed previously in patients sleeping in a laboratory or hospital. Furthermore, it suggests that hypertensive subjects do not have a higher centrally-induced vasoactive component and that hypotensive drugs do not alter the pattern of blood pressure behaviour induced by sleep.