Nocturnal fall of blood pressure and silent cerebrovascular damage in elderly hypertensive patients. Advanced silent cerebrovascular damage in extreme dippers

Circadian blood pressure and intraocular pressure patterns in normal tension glaucoma patients with undisturbed sleep

Purpose

To investigate and compare the circadian pattern of blood pressure (BP), intraocular pressure (IOP) and mean ocular perfusion pressure (MOPP) while experiencing undisturbed sleep in normal-tension glaucoma (NTG) and non-glaucoma control patient groups.

Methods

Twenty-four eyes from 24 patients diagnosed with NTG and 22 eyes from 22 control group patients were enrolled. Systolic BP, diastolic BP and IOP were measured every two hours except for the period of time from 1 AM to 7 AM in the NTG group and from 11 PM to 7 AM in the control group over a one-day period. IOP and hemodynamic parameters were then compared between the two groups. NTG patients were subdivided according to the degree of morning BP dip and IOP, and hemodynamic parameters and visual field indices (mean deviation and pattern standard deviation) were also compared among these subgroups.

Results

There were no significant differences in mean systolic BP, mean diastolic BP and mean arterial pressure (MAP) between the NTG and the control groups. The NTG group showed a significantly large morning BP dip compared to the control group (7.1±4.2% vs. 3.8±3.4%, p=0.022). However, there were no significant differences in mean or fluctuation of MOPP between the two groups. Morning over-dippers showed significantly large MAP and MOPP fluctuations compared to non-dippers and dippers, while there were no significant differences in visual field indices among the three subgroups.

Conclusions

NTG patients showed significant morning BP dips compared to the control group. The marked morning BP dip was associated with significantly large MAP or MOPP fluctuations but was not associated with visual field indices.

Fatigue and autonomic dysfunction in non-alcoholic fatty liver disease

BACKGROUND

Fatigue is a significant symptom in nonalcoholic fatty liver disease (NAFLD) that impacts upon quality of life and is unrelated to liver disease severity. We examined the relationship between parameters of blood pressure regulation with perception of fatigue in NAFLD.

METHODS

Thirty-four non-diabetic subjects with histologically proven, non-cirrhotic NAFLD (26 [77%] males and 8 [23%] females) (mean +/- SD age 54 +/- 11) and 34 age, sex and BMI matched non-diabetic controls underwent subjective and objective evaluation of cardiovascular autonomic function (24 h blood pressure and head up tilt testing). All subjects completed the fatigue impact scale.

RESULTS

The NAFLD group had significantly higher autonomic symptom burden assessed using the orthostatic grading scale (OGS) compared to controls (4 +/- 4 vs. 1 +/- 2; p = 0.0003). Increasing orthostatic symptoms correlated with increasing fatigue (p = 0.006; r(2) = 0.3). Fatigue in NAFLD correlated inversely with 24 h measurement of systolic, diastolic and mean blood pressures (all p < 0.03; r(2) = 0.2). This relationship was predominantly related to lower blood pressure at night (p < 0.003; r(2) = 0.3). On head up tilt testing 57% of the NAFLD group had neurally-mediated hypotension (vasovagal syncope and/or orthostatic hypotension) (p = 0.006 compared to controls). The degree of blood pressure drop in response to standing correlated with fatigue severity (p = 0.008; r(2) = 0.3) and the autonomic symptom burden (OGS) (p = 0.03; r(2) = 0.2).

CONCLUSION

Autonomic symptoms are prevalent in NAFLD and associate with objective measures of autonomic dysfunction. Fatigue in NAFLD is associated with lower blood pressure and autonomic dysfunction. Studies are needed to determine whether this is a potential therapeutic target for fatigue in NAFLD.

Obstructive sleep apnea syndrome and hypertension: ambulatory blood pressure

Obstructive sleep apnea syndrome (OSAS) is an independent risk factor for hypertension and cardiovascular disease. OSAS is the frequent underlying disease of secondary hypertension and resistant hypertension. OSAS increases both daytime and night-time ambulatory blood pressures through the activation of various neurohumoral factors including the sympathetic nervous system and the renin-angiotensin-aldosterone system. In particular, OSAS predominantly increases ambulatory BP during sleep compared with the awake period, with the result that OSAS is likely to be associated with the non-dipping pattern (diminished nocturnal BP fall) or riser pattern (higher sleep BP than awake BP) of nocturnal BP. An additional characteristic of ABP in OSAS is increased BP variability. The newly developed non-invasive hypoxia-trigger BP-monitoring system detected marked midnight BP surges (ranging from around 10 to 100 mm Hg) during sleep in OSAS patients. The exaggerated BP surge may trigger OSAS-related cardiovascular events occurring during sleep. Clinically, as nocturnal hypoxia is the determinant of morning minus evening BP difference (ME difference), OSAS should be strongly suspected when morning BP cannot be controlled <135/85 mm Hg with increased ME difference even by the specific antihypertensive medications targeting morning hypertension such as bedtime dosing of antihypertensive drugs. Understanding the characteristics of OSAS-related hypertension is essentially important to achieve perfect BP control over a 24-h period, including the sleep period, for more effective prevention of cardiovascular disease.

Blood pressure reactivity and cognitive function in the Baltimore Longitudinal Study of Aging

OBJECTIVE

Several blood pressure indexes of autonomic dysregulation, including stress-induced blood pressure responses (i.e., reactivity), have been associated previously with stroke, silent cerebrovascular disease, and decreased cognitive function.

DESIGN

The authors examined the cross-sectional relations among systolic blood pressure (SBP) and diastolic blood pressure (DBP) reactivity and cognitive function in a sample of stroke- and dementia-free older adults (n = 73, 53% male, 72% Caucasian, mean age = 70.14 years) from the Baltimore Longitudinal Study of Aging.

MAIN OUTCOME MEASURES

Age, education, baseline, and reactive blood pressure levels were regressed on cognitive test scores measuring the domains of attention, learning and memory, verbal functions/language skills, and perceptuo-motor speed. A Bonferroni correction was employed and results significant at the standard p < .05 level are discussed as marginally significant.

RESULTS

After adjustment for age, education, and resting blood pressure, greater SBP reactivity was associated with poorer performance on Digits Forward (R2 = .110, p = .007) and greater DBP reactivity was associated with poorer performance on Digits Forward (R(2) = .124, p = .003) and the Boston Naming Test (R(2) = .118, p = .008); associations with DBP reactivity and Alpha Span (R(2) = .104; p = .019) and CVLT free recall short delay (R(2) = .066, p = .032) were marginally significant.

CONCLUSIONS

Greater BP reactivity was associated with poorer performance on tests of attention, verbal memory, and confrontation naming. BP reactivity may be a biobehavioral risk factor for lowered levels of cognitive performance.

Nocturnal nondipping of heart rate predicts cardiovascular events in hypertensive patients

OBJECTIVE

It has not been established whether nocturnal nondipping of heart rate (HR) predicts future cardiovascular disease (CVD). We performed this study to test the hypothesis that nocturnal nondipping of HR predicts the risk of incident CVD independent of nocturnal blood pressure dipping pattern.

METHODS

Ambulatory blood pressure monitoring was performed in 457 uncomplicated patients, who were being treated or evaluated for hypertension. They were followed for an average of 72 +/- 26 months. Nondipping HR was defined as a night/day HR ratio greater than 0.90. We chose two outcomes for this analysis: CVD events (defined as stroke, myocardial infarction, or sudden cardiac death) and all-cause mortality. Cox regression analyses (stepwise method) were used to estimate hazard ratios and their 95% confidence interval after adjusting for covariates.

RESULTS

In univariate analysis, increased sleep HR and nondipping of HR were associated with increased risk of CVD and all-cause mortality, but awake HR was not. In multivariable analyses, HR nondipping status significantly predicted an increased risk of CVD events (hazard ratio, 2.37; 95% confidence interval, 1.22-4.62; P = 0.01), but not for all-cause mortality. Increased 24-h HR was significantly associated with increased risk of all-cause mortality (hazard ratio, 1.67; 95% confidence interval, 1.11-2.51; P = 0.01).

CONCLUSION

The risk of future CVD was shown to be 2.4 times higher in those whose HR does not exhibit the typical nocturnal decline. The relationship was independent of nondipping of SBP and was not dependent on diabetes status or blood pressure level.

Melatonin for nondippers with coronary artery disease: assessment of blood pressure profile and heart rate variability

The aim of this study was to assess the effects of 5 mg melatonin before sleep in patients with coronary artery disease (CAD) and with an abnormal circadian pattern of blood pressure (BP) on changes in circadian BP profile and heart rate variability (HRV). Sixty patients with CAD, nondippers aged 48-80 years (male 75%), were included. In addition to previous treatment, they were randomly allocated to melatonin or placebo. After 90 days, a second 24-h BP monitoring was carried out. Each patient had two sessions (before randomization and at the end of study) of 24-h ECG monitoring to assess the changes in HRV. Inclusion of melatonin led to BP pattern normalization in 35% of patients in the melatonin group and in 15% of controls (P=0.609). This effect was reached not only by a decrease in nighttime BP, but also by an increase in daytime BP (significant in the melatonin group). A nonoptimal effect for BP profile was observed in 12.5% of patients: extreme- or reverse dippers. In patients with conversion from nondippers to dippers (responders), an increase in standard deviation of normal-to-normal intervals between initial and final HRV analyses was observed. Nonresponders represented an increase in the mean circadian heart rate. To avoid nonoptimal effects, the inclusion of melatonin in pharmacotherapy of patients with CAD should be based on monitoring of circadian BP profile, before and during treatment. As melatonin caused not only a nocturnal decrease in BP but also a daytime increase, it should not be recommended in patients with 'high normal' values of BP because of the danger of induction of arterial hypertension.

Hypertension and TIA

Transient ischemic attack is a medical emergency because early stroke risk after transient ischemic attack is high. Hypertension is the most important modifiable risk factor for stroke and transient ischemic attack. The aims of this review are to provide a summary of the current knowledge concerning the relationship between blood pressure and transient ischemic attack, as well as outline issues regarding diurnal variation and the potential of chronotherapy (timing medications to accord with diurnal patterns of blood pressure). There is a strong relationship between hypertension and the incidence of transient ischemic attack and the subsequent short-term risk for stroke. Ambulatory blood pressure monitoring is a reliable diagnostic and monitoring tool for hypertension and provides additional information about diurnal variation in blood pressure. Different diurnal blood pressure patterns may confer variable stroke risk. Patients with stroke commonly have abnormal diurnal blood pressure patterns and this may relate, in part, to autonomic nervous system dysfunction. However, blood pressure patterns have not been systematically studied in patients with transient ischemic attack. Blood pressure remains poorly controlled in a large proportion of patients after transient ischemic attack and under-treatment and poor adherence are important factors. Chronotherapy for blood pressure may result in more effective blood pressure control. More research is needed in this area. Hypertension is strongly associated with transient ischemic attack. Diurnal blood pressure patterns may influence subsequent stroke risk after transient ischemic attack and more evidence is needed to inform clinical practice to improve blood pressure management for transient ischemic attack patients.

Can nocturnal hypertension predict cardiovascular risk?

Nocturnal hypertension and non-dipping of blood pressure during sleep are distinct entities that often occur together and are regarded as important harbingers of poor cardiovascular prognosis. This review addresses several aspects related to these blood pressure abnormalities including definitions, diagnostic limitations, pathogenesis and associated patient profiles, prognostic significance, and therapeutic strategies. Taken together, persistent nocturnal hypertension and non-dipping blood pressure pattern, perhaps secondary to abnormal renal sodium handling and/or altered nocturnal sympathovagal balance, are strongly associated with deaths, cardiovascular events, and progressive loss of renal function, independent of daytime and 24-hour blood pressure. Several pharmacological and non-pharmacological approaches may restore nocturnal blood pressure and circadian blood pressure rhythm to normal; however, whether this translates to a clinically meaningful reduction in unfavorable cardiovascular and renal consequences remains to be seen.

Exclusion of Influence of Physical Activity on Ambulatory Blood Pressure

OBJECTIVE

The basal blood pressure (BP) is more intimately related to hypertension severity than casual BP. BP values obtained by ambulatory blood pressure monitoring (ABPM) tend to be influenced by patients' physical activity because values are not always obtained with the patient at rest. The purpose of this study was to estimate the influence of physical activity on BP and determine daytime BP adjusted for activity as measured by ABPM.

METHODS

This study targeted three clinically different groups: healthy medical students (HS, n = 40), patients with hypertension (HT, n = 20), and patients with diabetes mellitus (DM, n = 7). The subjects' BP, heart rate (HR), and physical activity level were measured by a noninvasive portable multi-biomedical recorder. To identify the influence of physical activity on BP in the three study groups, a least squares regression analysis of the relation between BP and ACT (an index of activity with acceleration) was performed for each group.

RESULTS

ACT had a positive influence on systolic BP (SBP) in the HS, HT, and DM groups (R2 = 0.319, 0.576, 0.697, respectively). SBP adjusted for ACT (walking level) by means of the regression model with dummy variable was 0-24 mmHg lower than the value of SBP measured by ABPM, and daytime SBP (walking level) was overestimated by approximately 10 mmHg in comparison to the value of SBP at rest (ACT = 0).

CONCLUSION

Physical activity had a positive effect on SBP. The results showed that physical activity (walking-level) had a positive effect on SBP of about 10 mmHg.

Pressed for time: the circadian clock and hypertension

Hypertension is a major risk factor for cardiovascular disease and death. The "silent" rise of blood pressure that occurs over time is largely asymptomatic. However, its impact is deafening-causing and exacerbating cardiovascular disease, end-organ damage, and death. The present article addresses recent observations from human and animal studies that provide new insights into how the circadian clock regulates blood pressure, contributes to hypertension, and ultimately evolves vascular disease. Further, the molecular components of the circadian clock and their relationship with locomotor activity, metabolic control, fluid balance, and vascular resistance are discussed with an emphasis on how these novel, circadian clock-controlled mechanisms contribute to hypertension.

Cardiovascular disease, diabetes and established risk factors among populations of sub-Saharan African descent in Europe: a literature review

Background

Most European countries are ethnically and culturally diverse. Globally, cardiovascular disease (CVD) is the leading cause of death. The major risk factors for CVD have been well established. This picture holds true for all regions of the world and in different ethnic groups. However, the prevalence of CVD and related risk factors vary among ethnic groups.

Methods

This article provides a review of current understanding of the epidemiology of vascular disease, principally coronary heart disease (CHD), stroke and related risk factors among populations of Sub-Sahara African descent (henceforth, African descent) in comparison with the European populations in Europe.

Results

Compared with European populations, populations of African descent have an increased risk of stroke, whereas CHD is less common. They also have higher rates of hypertension and diabetes than European populations. Obesity is highly prevalent, but smoking rate is lower among African descent women. Older people of African descent have more favourable lipid profile and dietary habits than their European counterparts. Alcohol consumption is less common among populations of African descent. The rate of physical activity differs between European countries. Dutch African-Suriname men and women are less physically active than the White-Dutch whereas British African women are more physically active than women in the general population. Literature on psychosocial stress shows inconsistent results.

Conclusion

Hypertension and diabetes are highly prevalent among African populations, which may explain their high rate of stroke in Europe. The relatively low rate of CHD may be explained by the low rates of other risk factors including a more favourable lipid profile and the low prevalence of smoking. The risk factors are changing, and on the whole, getting worse especially among African women. Cohort studies and clinical trials are therefore needed among these groups to determine the relative contribution of vascular risk factors, and to help guide the prevention efforts. There is a clear need for intervention studies among these populations in Europe.

The structural and functional consequences of diurnal variations in blood pressure in treated patients with hypertensive cerebrovascular disease

BACKGROUND

Although hypertension is known to cause brain damage and cognitive impairment, epidemiological studies suggest that lower blood pressure (BP) in patients with established cerebrovascular disease is associated with more rapid cognitive decline. We investigated the relationship between 24-h ambulatory blood pressure (ABP) measurements, cerebrovascular disease load and cognitive performance in patients with hypertensive cerebrovascular disease.

METHODS

Eighty-eight patients (mean age 65+9 years) with hypertensive cerebrovascular disease on MRI were recruited. BP was controlled optimally. ABP monitoring, quantitative MRI analysis of white matter lesion (WML) volume and executive cognitive function tests were performed. The relationships between ABP variables, WML volume and executive test performance were examined using regression analyses to adjust for age, sex, vascular risk profile and premorbid intelligence.

RESULTS

Patients had a mean daytime ABP of 96+10 mmHg and mean night-time ABP of 88+11 mmHg (P = 0.001). Median WML volume was 8464 mm3. There were no significant associations between ABP variables and supratentorial WML volumes. Infratentorial WML volume correlated negatively with night-time mean BP (r = -0.6, P = 0.002) and positively with nocturnal dipping (r = 0.6, P = 0.002). Higher night-time mean BP was an independent predictor of reduced infratentorial WML volume (R2: 0.460, P = 0.008).Infratentorial WML volume correlated with impairments of phonemic verbal fluency (r = 0.5, P < 0.001) and choice reaction time (r = 0.7, P < 0.005).

CONCLUSION

Physiological falls in nocturnal BP may be associated with increased infratentorial WML volume and cognitive dysfunction in optimally controlled hypertensive patients with cerebrovascular disease.

Stress, menopausal status and nocturnal blood pressure dipping patterns among hypertensive women

BACKGROUND

A less than 10% decline in blood pressure during the night is known as a nondipping blood pressure (BP) pattern. Nondipping BP has been shown to be associated with target organ damage and poorer cardiovascular outcomes. Additionally, some evidence suggests that hyper-tensive nondipping women are at greater risk for target organ damage than hypertensive nondipping men.

OBJECTIVE

To determine whether stress, demographics, menopausal status or sleep quality are associated with nondipping BP among hyperten-sive women.

METHODS

A cross-sectional study design was used to describe the rela-tionship between stress and dipping status among a sample of hypertensive women and to describe the sample by age, ethnicity, marital status, meno-pausal status, current medications and sleep quality.

RESULTS

The study sample consisted of 47 women (mean [+/- SD] age 57+/-13.9 years) with essential or office hypertension who underwent 24 h ambulatory BP monitoring, and completed stress and sleep quality measurements. Thirty-one women (66%) were classified as dippers and 16 (34%) were classified as nondippers. Nondippers were older (P=0.04), postmenopausal (P=0.003) and had lower stress scores (P=0.02) than their dipper counterparts. Postmenopausal status sig-nificantly predicted nondipping (OR 16; 95% CI 1.9 to 136.4).

CONCLUSION

These findings were of interest given that some women had a nondipping BP pattern and significantly lower stress scores. It is pos-sible that there are fundamentally different physiological mechanisms that explain this nondipping phenomenon. In the future, the identification of specific hemodynamic mechanisms associated with nondipping could potentially influence the choice of antihypertensive treatment regimens for nondipper hypertensive patients.

Time for reflection predicts the progression of renal dysfunction in patients with nondiabetic chronic kidney disease

Our previous data indicated that both home blood pressure and arterial stiffness predicted the progression of renal dysfunction in the patients with chronic kidney diseases. In the present study, we examined both home blood pressure and the parameters of arterial stiffness as the indicator to the progression of chronic kidney diseases. Forty-two nondiabetic chronic kidney disease patients were enrolled and followed for 1 year. Anti-hypertensive therapy was adjusted to achieve office blood pressure below 130/80 mmHg. Home blood pressure was examined twice a day in the morning and evening. Pulse wave velocity (PWV) and augmentation index (AI) were measured as the index of arterial stiffness. The time for reflection (TR) was also determined. The relationship of annual changes in serum creatinine (Scr) with the above parameters was assessed. Multivariate regression analysis revealed that TR inversely correlated to annual increase in Scr (beta = -0.03, p < 0.05). Home blood pressure did not correlate to annual changes in Scr in the present study. The present data indicated that arterial stiffness is elevated despite good blood pressure control in chronic kidney disease, especially among the dippings. In addition, our data suggest that PWV and AI correlated to each other, while they were influenced differently by hemodynamic factors. Finally, the present findings provide the evidence that the arterial stiffness parameter is more sensitive than home blood pressure as an indicator to the progression of chronic kidney disease.

Clinical utility and applicability of smoothness index, normalized smoothness index and individualized RDH index during treatment of essential hypertension

The purpose of this study was to assess the clinical utility of the smoothness index (SI) and normalized SI (SIn), measures of duration and homogeneity of blood pressure (BP) reduction, during an observation period without antihypertensive therapy followed by a treatment period using dihydropyridines (DHP) in 54 newly diagnosed and previously untreated subjects (age 46.9 +/- 9.1 years) with essential hypertension. In addition, we aimed to describe the reduction-duration-homogeneity (RDH) index for statistical assessment of the BP reduction in the individual patient. Twenty-four-hour BP was lowered during treatment (139.2 +/- 13.9/ 91.0 +/- 7.6 mmHg vs 130.9 +/- 11.3/85.2 +/- 5.2 mmHg, p < 0.001/p = 0.001). SI showed great interindividual variation, and increased from zero to 0.9 +/- 0.8 (systolic BP) and 0.8 +/- 0.7 (diastolic BP) after treatment (p < 0.001 for both), similar results were obtained for SI(n). The RDH index revealed BP reduction in agreement with the change in individual 24-h, daytime and night-time BP. Although SI and SI(n) may add important information regarding the homogeneity of the antihypertensive effect in a group of patients, and the RDH index for the individual patient, conclusions regarding antihypertensive efficacy can be obtained from assessment of the 24-h, daytime and night-time BP changes and ambulatory BP profiles. Based on our findings, we do not recommend the use of SI or RDH index in the clinical practice.

Coronary flow reserve in dipper and non‐dipper hypertensive patients

BACKGROUND

Failure to decrease blood pressure (BP) normally during night-time, which is called non-dipping, in hypertensive individuals is associated with higher cardiovascular morbidity and mortality. In addition, non-dipping BP leads to structural changes in the left ventricle; however, the effect of non-dipping BP on coronary flow reserve (CFR) has not been studied yet.

METHODS

In this study, we measured CFR of 22 subjects with non-dipper hypertension, and 15 subjects with dipper hypertension using transthoracic second-harmonic Doppler echocardiography (Acuson Sequoia C256. None of the subjects had any systemic disease or coronary risk factor except hypertension.

RESULTS

Age, gender, body mass index, lipids and echocardiographic findings including left ventricular mass index were similar between the groups. Office BP recordings were similar between non-dipper and dipper groups (147.9+/-6.1/93.9+/-4.3 vs 144.0+/-8.0/93.0+/-3.7). Daytime and 24-h ambulatory BP measurements were similar within the groups, but night-time BPs were significantly greater in non-dipper group than those were in dipper group. Left ventricular diastolic and systolic functions, and both baseline and hyperemic peak diastolic coronary velocity as well as CFR, were similar between the non-dipper and dipper groups (CFR: 2.47+/-0.59 vs 2.39+/-0.47).

CONCLUSION

CFR were similar in patients with non-dipper and dipper hypertension in the absence of excessive left ventricular hypertrophy and other cardiovascular risk factors.

Bedtime administration of long-acting antihypertensive drugs restores normal nocturnal blood pressure fall in nondippers with essential hypertension

BACKGROUND

Nondipper hypertensive patients have more pronounced target organ injury. We examined whether shifting the time of dosing long-acting antihypertensive drugs from morning to bedtime reduces nocturnal blood pressure (BP) and restores normal nocturnal dipping in nondippers with essential hypertension.

METHODS

We studied 71 Japanese hypertensive patients who received long-acting antihypertensive drugs once daily in the morning using 24-h ambulatory BP monitoring. After determination of circadian BP pattern, medication time was changed to bedtime only in nondippers.

RESULTS

Among 71 patients, 36 were classified as dippers and 35 as nondippers. After shifting administration time from morning to bedtime in 34 nondippers, the office and 24-h ambulatory BP did not change, but the diurnal BP slightly increased and nocturnal BP markedly decreased. The percentages of nocturnal decline in systolic and diastolic BP increased from 2.6% to 15.5% (P < 0.0001) and 5.6% to 16.9% (P < 0.0001). Morning BP at 7 a.m.-11 a.m. did not increase by bedtime administration. The frequency of dippers increased from 0/34 (0%) to 24/34 (71%). Adding to 50% of dippers on morning administration, 86% of the hypertensive patients became dippers by deciding the medication time according to dipper status.

CONCLUSION

Nondippers on morning dosing can be changed to dippers by shifting administration time to bedtime, reducing nocturnal BP but not changing office BP, 24-h ambulatory BP or morning BP. In treating essential hypertensive patients, it is desirable to measure 24-h ambulatory BP as well as office BP and to decide the administration time of long-acting antihypertensive drugs to normalize nocturnal BP fall.

Lower ambulatory blood pressure in chronic fatigue syndrome

OBJECTIVE

To examine blood pressure circadian rhythm in subjects with chronic fatigue syndrome (CFS) and appropriate normal and fatigued controls to correlate parameters of blood pressure regulation with perception of fatigue in an observational cohort study. The cause of CFS remains unknown and there are no effective treatments.

METHODS

To address whether inactivity was a confounder, we performed a 24-hour ambulatory blood pressure monitoring in the following three subject groups: 1) CFS patients (Fukuda Diagnostic criteria) (n = 38); 2) normal controls (n = 120); and 3) a fatigue comparison group (n = 47) with the autoimmune liver disease primary biliary cirrhosis (PBC). All patients completed a measure of fatigue severity (Fatigue Impact Scale). In view of the different demographics between the patient groups, patients were age- and sex-matched on a case-by-case basis to normal controls and blood pressure parameters were compared.

RESULTS

Compared with the control population, the CFS group had significantly lower systolic blood pressure (p < .0001) and mean arterial blood pressure (p = .0002) and exaggerated diurnal variation (p = .009). There was a significant inverse relationship between increasing fatigue and diurnal variation of blood pressure in both the CFS and PBC groups (p < .05).

CONCLUSION

Lower blood pressure and abnormal diurnal blood pressure regulation occur in patients with CFS. We would suggest the need for a randomized, placebo-controlled trial of agents to increase blood pressure such as midodrine in CFS patients with an autonomic phenotype.

Night time blood pressure variability is a strong predictor for cardiovascular events in patients with type 2 diabetes

BACKGROUND

We aimed this study to test the hypothesis that short-term blood pressure (BP) variability and abnormal patterns of diurnal BP variation, evaluated by ambulatory BP (ABP), predicts risk of incident cardiovascular disease (CVD) in patients with type 2 diabetes (T2DM).

METHODS

ABP monitoring (ABPM) was performed in 300 patients with uncomplicated T2DM without known CVD and without BP medications, who were followed for 54 +/- 20 months. The relationships of different measures of BP variability, the presence of abnormal patterns of diurnal BP variation (nondipper, riser, or morning BP surge) and the standard deviations of awake and asleep ABP were determined. Cox proportional hazards models were used to estimate hazard ratios (HRs) and their 95% confidence intervals (CIs) before and after controlling for various covariates.

RESULTS

The mean age was 67.8 +/- 9.6 years, 48% were male, 253 (84%) had a diagnosis of hypertension, and the mean of the standard deviations of awake systolic BP/diastolic BP (SBP/DBP) were 18 +/- 6/11 +/- 4 mm Hg, and those of sleep SBP/DBP were 13 +/- 5/9 +/- 3 mm Hg. During follow-up, there were 29 cardiovascular events. In multivariable analyses, the standard deviations of sleep SBP (HR = 1.08; 95% CI, 1.01-1.16, P < 0.05) and sleep DBP (HR = 1.13; 1.04-1.23, P < 0.01) were independently associated with incident CVD. Neither the nondipper and riser patterns nor the morning BP surge were associated with incident CVD events independently of clinic and 24-h BP levels.

CONCLUSIONS

Abnormal diurnal BP variation was not a predictor of CVD in patients with T2DM. Night time BP variability was an independent predictor of future incidence of CVD, suggesting that this measure could reflect pathophysiology of T2DM.

Comparison of the anti-hypertensive effects of the L/N-type calcium channel antagonist cilnidipine, and the L-type calcium channel antagonist amlodipine in hypertensive patients with cerebrovascular disease

OBJECTIVES

It is known that the risk of cerebral stroke recurrence in post-stroke patients is comparatively higher than in normal subjects, and it is suggested that autonomic nervous system dysfunctions elevate this risk. We investigated the anti-hypertensive effects of cilnidipine, a Ca antagonist which suppresses sympathetic nerve activation, in hypertensives with chronic-stage cerebrovascular disease in a comparison with amlodipine.

METHODS

Amlodipine 5-7.5 mg/day, or cilnidipine 5-10 mg/day was administered to 78 hypertensive subjects (greater than 140 mmHg systolic, or 90 mmHg diastolic) undergoing outpatient treatment. Amlodipine or cilnidipine was also administered similarly, to 30 subjects having hypertension associated with a cerebral infarct which occurred more than one month earlier due to cerebral thrombosis or embolism. After 3 months administration, the subjects' blood pressures and pulse rates were recorded with an ambulatory blood pressure monitor over 24 hours.

RESULTS

No difference was recognized in patient age, gender, and systolic and diastolic blood pressure before treatment between the groups. In the cilnidipine groups, no difference in average 24-hour or waking systolic blood pressure values was seen between cerebrovascular disease (CVD) subjects and non-CVD subjects, although in the amlodipine groups, CVD subjects had significantly higher blood pressure values than non-CVD subjects. In the cilnidipine group, the coefficient of variation values of pulse rate were significantly higher in CVD subjects than in non-CVD subjects (p<0.05).

CONCLUSION

In patients with recent stroke, a Ca antagonist with no sympathetic nerve suppression had weaker blood pressure-lowering effects. Significantly increased pulse rate variability, shown in the CVD subjects administered cilnidipine, suggests that cilnidipine enhanced the parasympathetic function in hypertensive patients with CVD.

[Seven-day (24-hour) ambulatory blood pressure monitoring and frequently observed day-to-day differences in the elderly]

AIM

The goal of this study was to quantify the extent of possible day-to-day differences in 24-hour ambulatory blood pressure (ABP) monitoring results especially in association with age.

METHOD

A total of 514 community-dwelling subjects were initially recruited to participate in this study, and 450 subjects (average 58.8 years, 186 men and 264 women) had ABP monitoring for at least 6 days using an oscillometric monitor (TM-2430). We calculated the mean ABP and blood pressure (BP) dipping ratio for each day. Subjects were divided into 3 groups, 91 subjects aged from 40 to 49 years (average 41.8 years, younger group), 192 subjects from 50 to 64 years (average 57.5 years, middle-aged group), and 167 subjects over 65 years of age (average 69.5 years, elderly group). A mean ABP of >130/80 mm Hg was a criteria for hypertension (HT), and a decrease of less than 10% in BP during the night was defined as non-dipper. From the view point of day-to-day difference of ABP, 450 subjects were classified into (1) persistent normotension, masked ABP HT, intermittent ABP HT and persistent HT, and (2) persistent dipper, masked non-dipper, intermittent non-dipper and persistent non-dipper.

RESULTS

Frequency of masked and intermittent ABP HT was higher in the elderly group than the younger or middle-aged groups (47.3% vs. 27.5% or 39.6%), and the frequency of masked and intermittent non-dippers was also higher in association with age (55.0%, 59.5%, 69.7%, p<0.01).

CONCLUSION

Aging can affect ABP variability. ABP monitoring should be used more precisely for the better diagnosis and treatment of HT in the elderly.

Nocturnal blood pressure fall and metabolic syndrome score in patients with white coat hypertension

BACKGROUND

Accumulating data report that white coat hypertension (WCH) is associated with target organ damage. Metabolic syndrome (MS), and nondipping pattern is also associated with increased cardiovascular risk. The purpose of this study was to explore the nocturnal blood pressure fall in WCH patients according to their MS score.

METHODS

The study comprised 2300 patients with WCH who attended our outpatient clinics. All underwent repeated office blood pressure measurements, 24-h ambulatory blood pressure monitoring, full clinical and laboratory evaluation. The diagnosis of MS was made according to the Adult Treatment Panel III criteria and patients were classified into five groups: group I (hypertension), group II (hypertension and any one component), group III (hypertension and any two components), group IV (hypertension and any three components), and group V (all five components). Dipping pattern was defined as 'dippers' with nocturnal systolic blood pressure (NSBP) fall greater than or equal to 10% but less than 20%, 'nondippers' with NSBP fall greater than or equal to 0% but less than 10%, 'extreme dippers' with NSBP fall greater than or equal to 20%, and 'reverse dippers' with NSBP increase.

RESULTS

Patients were divided into two groups according to the presence (n=522) and absence (n=1778) of MS. The overall prevalence of MS in the study population was 22.7%. Comparing the non-MS group with the MS we observed significant differences for nondippers (24.5% vs. 38.9%, P<0.001), dippers (54.4% vs. 43.5%, P<0.001), extreme dippers (17.8% vs. 11.3%, P<0.001), and reverse dippers (3.3% vs. 6.3%, P=0.007).

CONCLUSION

Patients with WCH and increased number of MS components present with elevated nighttime SBP levels. This observation is of a great significance in the assessment of the cardiovascular risk in these patients.

Short sleep duration as an independent predictor of cardiovascular events in Japanese patients with hypertension

BACKGROUND

It is not known whether short duration of sleep is a predictor of future cardiovascular events in patients with hypertension.

METHODS

To test the hypothesis that short duration of sleep is independently associated with incident cardiovascular diseases (CVD), we performed ambulatory blood pressure (BP) monitoring in 1255 subjects with hypertension (mean [SD] age, 70.4 [9.9] years) and followed them for a mean period of 50 (23) months. Short sleep duration was defined as less than 7.5 hours (20th percentile). Multivariable Cox hazard models predicting CVD events were used to estimate the adjusted hazard ratio and 95% confidence interval (CI) for short sleep duration. A riser pattern was defined when mean nighttime systolic BP exceeded daytime systolic BP. The end point was a cardiovascular event: stroke, fatal or nonfatal myocardial infarction (MI), and sudden cardiac death.

RESULTS

In multivariable analyses, short duration of sleep (<7.5 hours) was associated with incident CVD (hazard ratio [HR], 1.68; 95% CI, 1.06-2.66; P = .03). A synergistic interaction was observed between short sleep duration and the riser pattern (P = .09). When subjects were classified according to their sleep time and a riser vs nonriser pattern, the group with shorter sleep duration plus the riser pattern had a substantially and significantly higher incidence of CVD than the group with predominant normal sleep duration plus the nonriser pattern (HR, 4.43; 95% CI, 2.09-9.39; P < .001), independent of covariates.

CONCLUSIONS

Short duration of sleep is associated with incident CVD risk and the combination of the riser pattern and short duration of sleep that is most strongly predictive of future CVD, independent of ambulatory BP levels. Physicians should inquire about sleep duration in the risk assessment of patients with hypertension.

Hypertension, cardiac hypertrophy, and impaired vascular relaxation induced by 2,3,7,8-tetrachlorodibenzo-p-dioxin are associated with increased superoxide

The mechanisms by which 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) increases the incidence of human cardiovascular disease are not known. We investigated the degree to which cardiovascular disease develops in mice following subchronic TCDD exposure. Adult male C57BL/6 mice were dosed with vehicle or 300 ng TCDD/kg by oral gavage three times per week for 60 days. Blood pressure was recorded by radiotelemetry and aortic endothelial function was assessed by acetylcholine-induced vasorelaxation. Mean arterial pressure of TCDD-exposed mice was increased significantly by day 4 and between days 7-10, 25-35, and 45-60 with two periods of normalization on days 11-24 and days 36-39. Consistent with a prolonged period of systemic hypertension, heart weight was increased and was associated with concentric left ventricular hypertrophy. Significant increases in superoxide production also were observed in the kidney, heart, and aorta of TCDD-exposed mice. Furthermore, increased aortic superoxide resulted in endothelial dysfunction as demonstrated by significant impairment of acetylcholine-induced vasorelaxation in TCDD-exposed mice, which was restored by tempol, a superoxide dismutase (SOD) mimetic. Our model is the first to definitely demonstrate that sustained AhR activation by TCDD increases blood pressure and induces cardiac hypertrophy, which may be mediated, in part, by increased superoxide.

Cardiovascular prognosis of sustained and white-coat hypertension in patients with type 2 diabetes mellitus

OBJECTIVE

Cardiovascular prognosis in diabetic white-coat hypertension (WCH) has not yet been described. We designed this study to investigate the impact of WCH on cardiovascular events in patients with type 2 diabetes, compared with those having type 2 diabetes along with sustained hypertension (SH), and with nondiabetic hypertensive individuals.

METHODS

We performed ambulatory blood pressure (BP) monitoring in 1207 consecutive hypertensive patients at baseline, and they were followed up for 49+/-22 months. The mean age was 70.7+/-9.8 years; 262 had type 2 diabetes; and 945 did not. They were classified as having SH with diabetes (n=210); diabetic WCH (n=52); SH alone (n=719); or WCH alone (n=226), using awake BP of 135/85 mmHg as the cutoff value. Cox regression models were used to calculate hazard ratios (HR) and 95% confidence intervals of the risk for cardiovascular events, after controlling for age, sex, body mass index, current smoking, serum creatinine, and clinical systolic BP.

RESULTS

During the follow-up period, 97 cardiovascular events occurred. The incidence of cardiovascular events in the diabetic SH group was significantly higher than in the diabetic WCH, nondiabetic SH, and nondiabetic WCH (P<0.05; log-rank test) groups. In Cox regression analysis, the diabetic SH group had significantly higher risk of cardiovascular events compared with the diabetic WCH group (HR: 8.2; 95% confidence intervals: 1.09-61.8; P=0.04). Although nonsignificant, the HRs in the SH and WCH groups, relative to diabetic WCH, exceeded 3.0.

CONCLUSIONS

The cardiovascular prognosis for diabetic WCH was better than that for diabetic SH during 4 years of follow-up.

Ambulatory blood pressure is a better marker than clinic blood pressure in predicting cardiovascular events in patients with/without type 2 diabetes

BACKGROUND

The prognostic significance of ambulatory blood pressure (ABP) has not been established in patients with type 2 diabetes (T2DM).

METHODS

In order to clarify the impact of ABP on cardiovascular prognosis in patients with or without T2DM, we performed ABP monitoring (ABPM) in 1,268 subjects recruited from nine sites in Japan, who were being evaluated for hypertension. The mean age of the patients was 70.4 +/- 9.9 years, and 301 of them had diabetes. The patients were followed up for 50 +/- 23 months. We investigated the relation between incidence of cardiovascular diseases (CVDs) and different measures of ABP, including three categories of awake systolic blood pressure (SBP <135, 135-150, and >150 mm Hg), sleep SBP (<120, 120-135, and >135 mm Hg), and dipping trends in nocturnal blood pressure (BP) (dippers, nondippers, and risers). Cox regression models were used in order to control for classic risk factors.

RESULTS

Higher awake and sleep SBPs predicted higher incidence of CVD in patients with and without diabetes. In multivariable analyses, elevated SBPs while awake and asleep predicted increased risk of CVD more accurately than clinic BP did, in both groups of patients. The relationships between ABP level and CVD were similar in both groups. In Kaplan-Meier analyses, the incidence of CVD in nondippers was similar to that in dippers, but risers experienced the highest risk of CVD in both groups (P < 0.01). The riser pattern was associated with a approximately 150% increase in risk of CVD, in both groups.

CONCLUSIONS

These findings suggest that ABPM is a better predictor of cardiovascular risk than clinic BP, and that this holds true for patients with or without T2DM.

Nocturnal blood pressure fall and metabolic syndrome score in hypertensive patients

BACKGROUND

Data relating dipping status to metabolic syndrome (MS) scores are not available. The purpose of this study is to investigate any possible association of different dipping patterns to MS scores in untreated patients with essential hypertension.

METHODS

The study included 6256 consecutive, treatment-naive patients with essential hypertension who attended our outpatient clinics. All underwent repeated office blood pressure measurements, 24-h ambulatory blood pressure monitoring, and full clinical and laboratory evaluation. The diagnosis of MS was made according to the Adult Treatment Panel III criteria and patients were classified into five groups: group I (hypertension), group II (hypertension+any one component), group III (hypertension+any two components), group IV (hypertension+any three components), and group V (all five components). Dipping pattern was defined as 'dippers' with nocturnal systolic blood pressure (NSBP) falling >or=10 but <20%, 'nondippers' with NSBP falling >or=0% but <10%, 'extreme dippers' with NSBP falling >or=20%, and 'reverse dippers' with NSBP increasing.

RESULTS

Hypertensive patients with MS (n=2573) had higher clinical and ambulatory blood pressure values (P<0.001), whereas the dominant dipping pattern in the non-MS group was nondippers (47.6%), and in the MS group, extreme dippers (37.8%). Furthermore, a considerable decrease in the prevalence of dippers was noticed with the increasing number of MS components (21.1 vs. 19.2 vs. 14.5 vs. 8.4 vs. 7.2%, P<0.001). In contrast, a significant rise in the prevalence of reverse dippers was observed with the increasing number of MS components (7.4 vs. 10.1 vs. 14.9 vs. 20.4 vs. 31.2%, P<0.001).

CONCLUSIONS

It seems that hypertensive patients have an increased prevalence of abnormal dipping patterns as the number of MS components rises.

History of gestational hypertension is associated with the metabolic syndrome and masked hypertension but not arterial stiffness in women with essential hypertension

The underlying mechanisms of subsequent increased risk of cardiovascular disease with a history of gestational hypertension (GH) are not known. Untreated hypertensive women (n=155, age 43+/-1 years) underwent ambulatory blood pressure (BP) monitoring and assessment of aortic pulse wave velocity (PWV) and augmentation index (AIx). Despite identical clinic BP readings, the group of women with GH (n=54) had higher (P=.002) ambulatory daytime systolic BP levels and a greater number of extreme nocturnal dippers (P=.005) than the group without GH. Women with GH had higher body mass index (P=.003), greater waist circumference (P=.02), higher levels of triglycerides (P=.002), lower levels of high-density lipoprotein cholesterol (P=.004), a higher prevalence of the metabolic syndrome (P<.05) and microalbuminuria (P=.004), higher plasma renin activity (P=.03), and higher aldosterone levels (P=.01). There was no significant difference in PWV and AIx between the 2 groups. The higher prevalence of the metabolic syndrome, microalbuminuria, masked hypertension, and activation of the renin-angiotensin-aldosterone system but not arterial stiffness may explain the subsequent propensity to high BP and cardiovascular disease in women with GH.

Reproducibility of the circadian blood pressure pattern in 24-h versus 48-h recordings: the Spanish Ambulatory Blood Pressure Monitoring Registry

OBJECTIVES

To assess the reproducibility of the circadian blood pressure (BP) pattern over a 48-h period by comparing the first 24 h of ambulatory blood pressure monitoring (ABPM) with the following 24 h and with the mean over 48 h.

PATIENTS AND METHODS

Patients undergoing 48-h ABPM within the National ABPM Registry of the Spanish Society of Hypertension, based on 800 Spacelabs 90207 monitors distributed throughout Spain in hypertension units and primary healthcare centres, were included. Between June 2004 and September 2005, 611 valid 48-h ABPM recordings were obtained, 235 corresponded to patients without antihypertensive treatment.

RESULTS

The percentages of patients classified as non-dipper for the first 24 h, the second 24 h and the 48-h average were 47, 50 and 48%, respectively. When the first and second 24-h periods were compared, 147 (24%) subjects switched from dipper (D) to non-dipper (ND) or vice-versa. When the first 24-h period was compared to the 48-h average, 66 (11%) subjects switched patterns. The proportions were similar separately for systolic blood pressure (SBP) and diastolic blood pressure (DBP) and between treated and untreated patients. In subjects with poor ABPM reproducibility, night-to-day ratios were of an intermediate value between those of subjects always classified as D or ND.

CONCLUSION

Categorization of D or ND based on a single 24-h ABPM is moderately reproducible, since one out of every five patients change profile over the following 24 h. Nevertheless, the use of 48-h ABPM in clinical practice should be assessed according to cost-effectiveness criteria. Night-to-day ratios may be helpful in identifying patients with a stable profile.

Risk factors for vascular dementia: hypotension as a key point

Physiologically, the cerebral autoregulation system allows maintenance of constant cerebral blood flow over a wide range of blood pressure. In old people, there is a progressive reshape of cerebral autoregulation from a sigmoid curve to a straight line. This implies that any abrupt change in blood pressure will result in a rapid and significant change in cerebral blood flow. Hypertension has often been observed to be a risk factor for vascular dementia (VaD) and sometimes for Alzheimer disease although not always. Indeed, high blood pressure may accelerate cerebral white matter lesions, but white matter lesions have been found to be facilitated by excessive fall in blood pressure, including orthostatic dysregulation and postprandial hypotension. Many recent studies observed among other data, that there was a correlation between systolic pressure reduction and cognitive decline in women, which was not accounted for by other factors. Baseline blood pressure level was not significantly related to cognitive decline with initial good cognition. Some researchers speculate that blood pressure reduction might be an early change of the dementing process. The most confounding factor is that low pressure by itself might be a predictor of death; nevertheless, the effect of low blood pressure on cognition is underestimated because of a survival bias. Another explanation is that clinically unrecognized vascular lesions in the brain or atherosclerosis are responsible for both cognitive decline and blood pressure reduction. We discuss the entire process, and try to define a possible mechanism that is able to explain the dynamic by which hypotension might be related to dementia.

Masked hypertension in diabetes mellitus: a potential risk

The prevalence and clinical significance of masked hypertension (MHT) in diabetics have infrequently been described. The authors assessed the association of MHT (defined using a clinic blood pressure [BP] <140/90 mm Hg and daytime ambulatory BP > or = 135/85 mm Hg) with microvascular and macrovascular end organ damage in 81 clinically normotensive Japanese diabetic persons. The prevalence of silent cerebral infarcts (SCIs), increased left ventricular mass, and albuminuria were evaluated. Of 81 patients, 38 (46.9%) were classified as having MHT and showed significantly more SCIs (mean +/- SE: 2.5+/-0.5 vs 1.1+/-0.2; P=.017), and more albuminuria (39% vs 16%; P=.025), but no increase in left ventricular mass index, than the normotensive persons in office and on ambulatory BP monitoring group. The prevalence of MHT in this diabetic population was high (47%). Diabetic patients with MHT showed evidence of brain and kidney damage. Hence, out-of-office monitoring of BP may be indicated in diabetics whose BP is normal in the clinic.

Exploring the use of feminist philosophy within nursing research to enhance post-positivist methodologies in the study of cardiovascular health

Nursing has historically relied heavily on scientific knowledge. It is not surprising that the cardiovascular health literature has been highly influenced by the post-positivist philosophy. The nursing discipline, as well as the cardiovascular nursing specialty, continues to benefit from research grounded within this philosophical tradition. At the same time, there are limitations associated with post-positivism. Therefore, it is beneficial for researchers and clinicians to examine the potential contributions various philosophical traditions can have for their research and practice. This paper is an exploration of the compatibilities of feminist and post-positivist philosophies in the study of cardiovascular nursing research. The ensuing discussion entails an examination of my clinical and research interests, the grounding of my research within the post-positivist perspective and the significant contribution feminist philosophy can make to my research.

Chronotherapy of hypertension: administration-time-dependent effects of treatment on the circadian pattern of blood pressure

Some specific features of the 24-hour blood pressure (BP) pattern are linked to the progressive injury of target tissues and the triggering of cardiac and cerebrovascular events. Thus, there is growing interest in how to best tailor the treatment of hypertensive patients according to the circadian BP pattern of each individual. Significant administration-time differences in the kinetics (i.e., chronokinetics) plus beneficial and adverse effects (i.e., chronodynamics) of antihypertensive medications are well known. Thus, bedtime dosing with nifedipine GITS is more effective than morning dosing, while also significantly reducing adverse effects. The dose-response curve, therapeutic coverage, and efficacy of doxazosin GITS are all markedly dependent on the circadian time of drug administration. Moreover, valsartan administration at bedtime, as opposed to upon wakening, results in an improved diurnal/nocturnal BP ratio, increased percentage of controlled patients, and significant reduction in urinary albumin excretion in hypertensive patients. Chronotherapy provides a means of individualizing the treatment of hypertension according to the circadian BP profile of each patient, and constitutes a new option to optimize BP control and to reduce the risk of cardiovascular disease (myocardial infarction and stroke) and of end-organ injury of the blood vessels and tissue of the heart, brain, kidney, eye, and other organs.

Relation between serum calcium, phosphate, parathyroid hormone and 'nondipper' circadian blood pressure variability profile in patients with normal renal function

BACKGROUND AND AIMS

In patients with renal disease, an association between abnormal circadian blood pressure profile and abnormalities in bone and mineral metabolism, including vascular calcifications, is well known. However, such a link has not yet been reported in hypertensive patients with normal renal function. We aimed to evaluate if higher serum phosphate, calcium, parathyroid hormone (PTH) level and the calcium x phosphate (Ca x P) product would be associated with a nondipper hypertension, in patients with normal renal function and without any PTH disorder.

METHODS

190 hypertensive subjects with the following inclusion criteria were enrolled: (1) normal phosphate and PTH levels; (2) glomerular filtration rate (GFR) >60 ml/min, and (3) no history of calcium, phosphate, vitamin D medication and hyperparathyroidism.

RESULTS

Of the total population, 76 patients (40%) were classified as dippers and 114 (60%) as nondippers. Nondipper patients had higher levels of phosphate (3.70 +/- 0.61 vs. 3.35 +/- 0.44 mg/dl, p = 0.001), Ca x P product (35.4 +/- 6.5 vs. 31.5 +/- 5.0, p = 0.001) and PTH (75.7 +/- 28.8 vs. 46.6 +/- 17.1 pg/ml, p = 0.000) compared to dipper patients. Independent predictors (multiple regression) for nondipper hypertension were PTH (beta = 0.43, p = 0.001) and phosphate (beta = 0.9, p = 0.03).

CONCLUSION

We demonstrate a graded independent relation between higher levels of phosphate, PTH, Ca x P product and the risk of nondipping in hypertensive patients with an estimated GFR of >60 ml/min and normal mineral metabolism.