Nocturnal Blood Pressure Dipping Research Articles

Proposing arterial stiffness as an alternative way of assessing risk in transient ischaemic attack (TIA) patients

Background: The ABCD2 score is a clinical tool currently categorising transient ischaemic attack (TIA) patients as low or high risk. Arterial stiffness, a novel physiological parameter predicting future cardiovascular events, has not been explored in TIA populations. Methods: The following arterial stiffness parameters were measured in TIA patients aged >40 years: carotid-femoral pulse wave velocity (C-F PWV), carotid-radial pulse wave velocity (C-R PWV) using Complior® and central and peripheral blood pressure (BP) using Arteriograph®. Nocturnal BP dipping profiles were measured using 24-h ambulatory blood pressure monitoring. TIA participants were age- and gender-matched with healthy subjects to compare arterial stiffness and BP profiles. Results: Twenty-four TIA patients, 50% male, of mean±SD age 70±10.1 years were recruited to the study. Mean±SD C-F PWV was 11.5±3.18 m/s and C-R PWV was 10.8±1.26 m/s. Published normative data for healthy age- and gender-matched subjects are C-F PWV 10.9 m/s and C-R PWV 10.1 m/s. Our TIA patients had higher central (130 mmHg) than peripheral BP (128 mmHg) compared with healthy subjects in whom central BP is 10–15 mmHg lower than peripheral BP. Thirty-eight percent of TIA patients lacked nocturnal dipping compared with 19% of healthy subjects. Conclusions: In our TIA cohort we found increased arterial stiffness measurements compared to healthy subjects.

Psychosocial Correlates of Nocturnal Blood Pressure Dipping in African Americans: The Jackson Heart Study.

African Americans exhibit a lower degree of nocturnal blood pressure (BP) dipping compared with Whites, but the reasons for reduced BP dipping in this group are not fully understood. The aim of this study was to identify psychosocial factors associated with BP dipping in a population-based cohort of African Americans. This cross-sectional study included 668 Jackson Heart Study (JHS) participants with valid 24-hour ambulatory BP data and complete data on psychosocial factors of interest including stress, negative emotions, and psychosocial resources (e.g., perceived support). The association of each psychosocial factor with BP dipping percentage and nondipping status (defined as <10% BP dipping) was assessed using linear and Poisson regression models, respectively, with progressive adjustment for demographic, socioeconomic, biomedical, and behavioral factors. The prevalence of nondipping was 64%. Higher depressive symptoms, higher hostility, and lower perceived social support were associated with a lower BP dipping percentage in unadjusted models and after adjustment for age, sex, body mass index, and mean 24-hour systolic BP (P < 0.05). Only perceived support was associated with BP dipping percentage in fully adjusted models. Also, after full multivariable adjustment, the prevalence ratio for nondipping BP associated with 1 SD (7.1 unit) increase in perceived support was 0.93 (95% CI: 0.88-0.99). No other psychosocial factors were associated with nondipping status. Lower perceived support was associated with reduced BP dipping in this study. The role of social support as a potentially modifiable determinant of nocturnal BP dipping warrants further investigation.

24-Hour Ambulatory Blood Pressure Monitoring in SWEDDs Patients With Parkinsonism.

Patients diagnosed with Parkinson's disease (PD) on clinics who subsequently turn out to have normal dopamine transporter images have been referred to as scans without evidence of dopaminergic deficits (SWEDDs) patients. Cardiovascular autonomic dysfunction has frequently been reported in PD. In this study, we determined the similarities and differences in cardiac autonomic dysfunction between SWEDDs and PD patients. This study investigated whether 24-hour ambulatory blood pressure monitoring (24-hour ABPM) can help identify possible cases with SWEDDs. We enrolled 28 SWEDDs patients, 46 patients with PD, and 30 healthy controls. To evaluate cardiac autonomic function, 24-hour ABPM was performed on all subjects. Cardiac metaiodobenzylguanidine (MIBG) scintigraphy was performed on the SWEDDs and PD subjects. The percentage nocturnal decline in blood pressure differed significantly among SWEDDs patients, PD patients, and controls (p<0.05). In addition to the abnormal nocturnal BP, regulation (nondipping and reverse dipping) was significantly higher in SWEDDs and PD subjects than in the control subjects (p<0.05). There was no significant correlation between the % nocturnal blood pressure reduction and parameters of cardiac MIBG uptake ratio. However, orthostatic hypotension was significant correlated with the nocturnal blood pressure dip (%), nocturnal blood pressure patterns, and the cardiac MIBG uptake ratio (early and late) in combined SWEDDs and PD subjects. Pathologic nocturnal blood pressure regulation and nocturnal hypertension, known characteristics of PD, are also present in SWEDDs. Moreover, cardiac sympathetic denervation should not be attributed to cardiac autonomic dysfunction in SWEDDs patients. As with PD patients, the SWEDDs patients studied here tended to have cardiac autonomic dysfunction.

Current clinical aspects of ambulatory blood pressure monitoring

Systemic arterial hypertension is the prevalentest disease worldwide that significantly increases cardiovascular risk. An early diagnosis together to achieve goals decreases the risk of complications significatly. Recently have been updated the diagnostic criteria for hypertension and the introduction of ambulatory blood pressure monitoring. The introduction into clinical practice of ambulatory blood pressure monitoring was to assist the diagnosis of «white coat hypertension» and «masked hypertension». Today has also shown that ambulatory blood pressure monitoring is better than the traditional method of recording blood pressure in the office, to the diagnosis and to adequate control and adjustment of drug treatment. Also there have been introduced important new concepts such as isloted nocturnal hypertension, morning blood pressure elevation altered and altered patterns of nocturnal dip in blood pressure; which have been associated with increased cardiovascular risk. Several studies have shown significant prognostic value in some stocks. There are still other concepts on which further study is needed to properly establish their introduction to clinical practice as hypertensive load variability, pulse pressure and arterial stiffness. In addition to setting values according to further clinical studies in populations such as elderly and children.

Association between nocturnal blood pressure dipping and arterial stiffness in patients with mild obstructive sleep apnea

Association between nocturnal blood pressure dipping and arterial stiffness in patients with mild obstructive sleep apnea

Masked Hypertension and Morning Blood Pressure Surge in Patients with Obstructive Sleep Apnea Syndrome

Objective: Frequent hypoxic episodes and arousal during sleep in obstructive sleep apnea syndrome (OSAS) result in increased nocturnal blood pressure, which in turn may lead to sustained hypertension. Patients with severe OSAS exhibit attenuated nocturnal blood pressure (BP) dipping, as well as marked and rapid BP elevation in the morning shortly after waking. We examined the prevalence of masked hypertension and morning BP surge in patients with OSAS, and the relationship between the severity of OSAS and abnormal circadian BP patterns. Methods: We performed 24-hour ambulatory BP monitoring in the absence of antihypertensive medication on 26 patients with OSAS (49.3 ± 8.4 yrs) to investigate masked hypertension and morning BP surge. Results: Results of the 26 patients, three (11.7%) were normotensive, six (23.0%) exhibited masked hypertension, and 17 (65.3%) were hypertensive. The apnea/hypopnea index was significantly correlated with 24-hour mean, daytime, and night time systolic and diastolic BP. 24-hour mean, daytime, and night time BPs in the severe OSAS group were significantly higher than in the mild to moderate OSAS group. We observed morning BP surge in 16 patients (61.5%). There were no significant differences in the prevalence of morning BP surge and masked hypertension between the mild to moderate and the severe OSAS groups. Conclusion: Mild to moderate OSAS may play an important role in masked hypertension and morning BP surge.

Nocturnal Hypertension and Attenuated Nocturnal Blood Pressure Dipping is Common in Pediatric Lupus

Hypertension is an important manifestation of systemic lupus erythematosus (SLE) but reports of prevalence vary between 20-70% in published reports of adult and pediatric patients. For both children and adults with SLE, the clinical diagnosis and management of hypertension has traditionally been based on guidelines developed for the general population. In clinical trials, the criteria used for defining participants with hypertension are mostly undefined. As a first step towards formally assessing the blood pressure (BP) patterns of children diagnosed with SLE, 24-hr ambulatory BP monitoring data was analyzed on clinic patients who presented with prehypertension or stage I hypertension. In this pediatric SLE cohort (n=10), 20% met daytime criteria for a diagnosis of hypertension. Patterns of BP elevation varied widely with white coat, masked, isolated systolic, and diastolic nocturnal hypertension all identified. Nocturnal hypertension was detected in 60% and attenuated nocturnal BP dipping in 90% of both hypertensive and normotensive SLE patients. In SLE patients, the median nighttime systolic and diastolic loads were 25% and 15.5% compared with median daily loads of 12.5% and 11.5%. Daytime and nighttime systolic and diastolic BP load and nocturnal dipping was compared to a control population consisting of 85 non-SLE patients under 21 years old with prehypertension or stage 1 hypertension presenting to hypertension clinic. Median systolic BP dipped 5.3 mmHg in SLE patients compared to 11.9 mmHg in non-lupus ( p-value = 0.001). Median diastolic BP dipped 12.9 mmHg versus 18.5 mmHg in non-lupus ( p-value = 0.003). Patterns of BP dysregulation in pediatric SLE merit further exploration. Children with or without SLE displaying prehypertensive or stage 1 casual BP measurements had similar rates of hypertension by ambulatory BP monitoring. However, regardless of BP diagnosis, and independent of kidney involvement, there was an increased proportion with attenuated nocturnal dipping and nocturnal hypertension in SLE patients.

Arterial blood pressure monitoring in children

In 2008 the first set of consensus recommendations for performance and interpretation of 24 hours Arterial Blood Pressure Monitoring (ABPM) in children and adolescents have been published [1]. Since then, ABPM has found increasing use in pediatrics. These recommendations have been updated in 2014 [2]. For this reason the Group of Hypertension Study of the Italian Society of Pediatrics (GISPER) has felt the need to perform an update of the Italian recommendations on this topic. The ABPM should be used by experts who know how to run it and interpret it. Proper execution is in fact necessary and only trained staff can guarantee it. Children and parents should be educated on the significance of the examination and care should be taken in selection of the appropriate size cuff according to the size of the child's arm. For the interpretation of the ABPM data, the age- and sex-specific percentiles of Wuhl et al [3] are the preferred reference nomograms. Table ​Table11 shows the suggesting schema for interpretation of ABPM values, in defining Blood Pressure categories. On the contrary that in the adult, the ABPM in children cannot be considered the gold standard for the diagnosis of high blood pressure, which must be done by measuring office Blood Pressure values, according to the criteria established by the National High Blood Pressure Education Program Working Group on High Blood Pressure in Children and Adolescents [4]. Other important differences compared to adults are using the pressure load (defined as pathological in the presence of a number of measurements of systolic or diastolic Blood Pressure values >25% of total) to define the different blood pressure categories and the presence of Pre-Hypertension among Blood Pressure categories. The ABPM also allows to identify individuals with White Coat or Masked Hypertension, clinical situations that, in children as in adults, suggest the need for careful follow-up. It was shown that both of these conditions can be associated with the presence of early organ damage, such as left ventricular hypertrophy in children. Finally, ABPM can give important information about Blood Pressure variability, distinguishing subjects with normal nocturnal Blood Pressure dip (>10% compared to the day, dipping), from non-dipping children. Table 1 Suggesting schema for Ambulatory Blood Pressure levels interpretation in children (modified by ref.2)

Association of depressive symptoms with circadian blood pressure alterations in Parkinson's disease.

To assess whether among patients with Parkinson's disease (PD) depression, a common non-motor symptom associated with reduced survival, is associated with cardiovascular dysautonomia. We enrolled 125 subjects with PD consecutively admitted to a geriatric day hospital. All participants underwent comprehensive evaluation, fasting blood sampling, and 24-h ambulatory blood pressure monitoring. The percent reduction in nocturnal blood pressure (dipping) was calculated. Depressive symptoms were assessed through the 15-item Geriatric Depression Scale (GDS); a score ≥5 identified moderate to severe symptoms. Among participants (mean age 72.7 ± 7.8 years, 32 % women) 61 subjects (49 %) presented with a GDS score ≥ 5. When compared with other participants, subjects with a GDS score ≥ 5 had reduced adjusted levels of percent systolic (-2.6 ± 2.7 vs. 4.7 ± 2.5; p = 0.003), diastolic (0.6 ± 2.8 vs. 7.4 ± 2.6; p = 0.007), and mean blood pressure dipping (-0.7 ± 2.6 vs. 6.8 ± 2.5; p = 0.002). In separate logistic regression models, depressive symptoms were associated with reduced systolic (OR 0.94; 95 % CI 0.89; 0.98), diastolic (OR 0.94; 95 % CI 0.90; 0.99), and mean blood pressure dipping (OR 0.93; 95 % CI 0.89; 0.98), after adjusting for potential confounders. Depressive symptoms are prevalent, and independently associated with cardiovascular dysautonomia among patients with Parkinson's disease. This might explain the remarkable incidence of sudden death, as well as the association of depressive symptoms with reduced survival reported in these patients. The finding of depressive symptoms in subjects with Parkinson's disease should therefore prompt assessment of cardiovascular autonomic function.

Angiotensin-converting enzyme insertion/deletion polymorphism, 24-h blood pressure profile and left ventricular hypertrophy in hypertensive individuals: a cross-sectional study.

BackgroundThe absence of nocturnal blood pressure dipping (ND) identified by 24-h ambulatory blood pressure monitoring (ABPM) correlates with a worse cardiovascular prognosis. The renin–angiotensin system influences blood pressure levels and the occurrence of target organ damage (TOD). Thus, the aim of this study was to correlate the angiotensin-converting enzyme gene (ACE) insertion/deletion (I/D) polymorphism with the 24-h blood pressure profile and TOD in hypertensive individuals.Methods155 non-diabetic hypertensive individuals on antihypertensive treatment underwent ABPM. Peripheral blood samples were drawn for biochemistry and genetic analysis of the ACE I/D polymorphism by polymerase chain reaction. ND was defined as ≥10 % differences in the mean systolic blood pressure (BP) during wakefulness and sleep.ResultsThere were no differences in clinical or biochemical variables or TOD in respect to ND status, except for higher BP levels during sleep (p < 0.001) in non-dippers. There was significant difference in the prevalence of left ventricular hypertrophy (LVH) between ACE genotypes (II: 13.0 %; ID: 34.1 %; DD: 46.5 %; p value = 0.024) with an increased risk in carriers of the DD genotype (OR = 5.80; IC 95 % 1.50–22.44; p value = 0.011). Carriers of the D allele had higher systolic BP during wakefulness and by ABPM (p < 0.05), higher left ventricular mass (117.3 ± 50.0 vs. 100.3 ± 25.7; p value = 0.017) and higher prevalence of LVH (37.4 vs. 12.5 %; OR = 4.14; 95 % IC: 1.17–14.65; p value = 0.028), compared to the II genotype.ConclusionsThe DD genotype is associated with a higher prevalence of LVH. The presence of the D allele appears to be associated with higher mean 24-h and wake systolic BP measured by ABPM in hypertensive patients under antihypertensive treatment.

57 Novel roles for dietary nitrate in non ischaemic dilated cardiomyopathy and resistant hypertension

Introduction Non ischaemic dilated cardiomyopathy (NIDCM) and resistant hypertension (HTN) are common, chronic diseases. Blood nitrate/nitrite indicate nitric oxide (NO) bioavailability and levels are typically lower in NIDCM and HTN compared to controls indicating perturbed nitric oxide (NO) metabolism. In addition to the well-characterised L-arginine-NO synthase pathway, a second independent pathway for NO synthesis in vivo has been recently discovered whereby dietary nitrate is reduced to nitrite and consequently NO. Exploitation of this pathway represents a promising strategy for increasing NO bioavailability, with possible physiological benefits. Methods To assess effects in HTN, 19 eligible subjects wore an ambulatory blood pressure (BP) monitor (ABPM) for 24 h and fasting blood was taken before and after 14 d of nitrate-rich beetroot juice (BRJ). To assess effects in NIDCM, we recorded exercise capacity (incremental shuttle walk test) and BP before and 3 h after both BRJ and placebo in a randomised, double-blind, crossover trial among 11 subjects. There was 7 d between testing days with the alternate beverage. Results In the HTN study, 11 subjects had controlled blood pressure while 8 had uncontrolled blood pressure. There were similar increases in serum nitrate (p = 0.01) and nitrite (p = 0.001) in both controlled and uncontrolled hypertension. Further, there were no differences in either group regarding serum lipids (triglycerides, total cholesterol, LDL cholesterol, HDL cholesterol). We observed very little chance in BP variables among the controlled hypertensives. In contrast, there were reductions in 24 h, daytime, and nighttime BP as well an increase in nocturnal BP dipping. The decreases in mean nighttime DBP and ambulatory arterial stiffness index (AASI) reached significance (p = 0.03 and p = 0.05 respectively). In the NIDCM trial, there were no significant differences in heart rate, arterial oxygen concentrations, breathlessness, leg fatigue or blood pressure at any time point with either beverage. However, NIDCM subjects walked significantly when took BRJ (+65 m) than when they took PL (-5 m) (p = 0.006). Conclusions Dietary nitrate has potential as a novel therapeutic, adjunct strategy to increase NO bioavailability in cardiovascular disease with potential physiological benefits. Our preliminary results require confirmation in larger trials. However, considering the low cost and safety profile of dietary nitrate containing foods and supplements, this concept appears promising as an adjunct therapeutic strategy for cardiovascular diseases.

Prospective analysis of the association of ambulatory blood pressure characteristics with incident chronic kidney disease.

Ambulatory blood pressure measurement allows quantification of diurnal changes in blood pressure. While decreased nocturnal blood pressure dipping and elevated morning blood pressure surge are associated with an increased risk of cardiovascular events, the utility of ambulatory blood pressure measurements to predict renal events is unclear. African Americans, in addition to having an increased risk of chronic kidney disease (CKD), also have an increased prevalence of hypertension. Thus, we selected an African American population to study the association of ambulatory blood pressure parameters with incidence of CKD. Prospective cohort study of 603 participants with normal renal function enrolled in the Jackson Heart Study who underwent baseline 24-h ambulatory blood pressure monitoring between 2000 and 2004, with median follow-up of 8.1 years. We analyzed the association of nocturnal dipping and morning surge with both incident CKD [estimated glomerular filtration rate (eGFR) <60 ml/min per 1.73 m] and annual rate of eGFR decline. In additional analyses, we examined the relation of nocturnal, daytime, white-coat, and masked hypertension with CKD incidence. We found that 10% higher nocturnal dipping was significantly associated with a decreased risk of incident CKD [odds ratio (OR) 0.55, 95% confidence interval (CI) 0.32-0.96] and a 0.4 ml/min per 1.73 m slower annual decline in eGFR. Morning surge was not associated with the incidence of CKD. Additional analyses revealed that isolated nocturnal hypertension and mean asleep SBP were associated with a nonsignificantly higher risk of CKD (OR 2.34, 95% CI 0.90-6.08) and (OR 1.31, 95% CI 0.99-1.72), respectively, in fully adjusted models. Loss of nocturnal blood pressure dipping, but not morning blood pressure surge, may promote the decline in GFR and increase the risk for development of CKD in high-risk individuals.

Abstract P235: Employing the DASH Diet to Treat Non-dippers: A Two-month Intervention Study

Introduction: Hypertensive patients with abnormal circadian blood pressure patterns, including a lack of nocturnal blood pressure dipping or rises in blood pressure from daytime to night-time, are at an increased risk for numerous cardiovascular events including strokes, heart failure and renal failure. Currently, limited therapeutic strategies exist to treat non-dippers. In this study, we examine the role of obesity on circadian blood pressure patterns and the impact of lifestyle intervention on nocturnal dip. Methodology: 24-hour ambulatory blood pressure monitoring was performed before and after a 2-month intervention employing the DASH diet and lifestyle program with a targeted 5% weight loss in 80 volunteers. 20 control patients had a healthy nocturnal dip, 30 patients had a non-dipping blood pressure pattern, and 30 patients had a rise in blood pressure nocturnally from daytime. Results: At baseline, there was a linear correlation between individuals' BMI and nocturnal blood pressure aberrancies (r= 0.60, p&lt;0.0001). The control group had the lowest average BMI of 28.1 kg/m2. Non-dippers had a slightly higher average BMI of 30.3 kg/m2, and those with a rise in blood pressure nocturnally had the greatest average BMI of 35.3 kg/m2. After the two-month lifestyle intervention, individuals who achieved weight loss had significantly greater average reductions in nocturnal blood pressure (24.3 mm Hg), compared to daytime (12.1 mm Hg), resulting in the restoration of a more normal nocturnal dip and circadian blood pressure pattern. Non-dippers who achieved a 5% reduction in weight during the intervention had an average 8.31% nocturnal dip by the end of the study. Individuals who lost less than 5% of their weight or who gained weight continued to have a non-dipping blood pressure pattern by the end of the study. Conclusions: The results of this study would suggest that perhaps reducing weight by adhering to the DASH diet and lifestyle intervention could be examined as therapeutic avenues for non-dippers in the future. The long-term effects of a restoration of normal circadian blood pressure pattern warrants further investigation.

The Association of Pediatric Obesity With Nocturnal Non-Dipping on 24-Hour Ambulatory Blood Pressure Monitoring.

Obesity has been linked with abnormal nocturnal dipping of blood pressure (BP) in adults, which in turn is associated with poor cardiovascular outcomes. There are few data regarding abnormal dipping status in the obese pediatric population. The goal of this study was to further describe the relationship between obesity and non-dipping status on ambulatory blood pressure monitor (ABPM) in children. We conducted a cross-sectional study using a database of patients aged 5-21 years who had undergone 24-hour ABPM at Seattle Children's Hospital from January 2008 through May 2014. Subjects were grouped by body mass index (BMI) into lean (BMI 15th-85th percentile) and obese (BMI >95th percentile) groups. Compared to lean subjects (n = 161), obese subjects (n = 247) had a prevalence ratio (PR) for non-dipping of 2.15, adjusted for race (95% confidence interval (CI) = 1.25-3.42). Increasing severity of obesity was not further associated with nocturnal non-dipping. Nocturnal non-dipping was not associated with left ventricular hypertrophy (PR = 1.01, 95% CI = 0.71-1.44). These results suggest that in children, just as in adults, obesity is related to a relatively decreased dipping in nocturnal BP.

Nocturnal Hypertension and Attenuated Nocturnal Blood Pressure Dipping is Common in Pediatric Lupus

Hypertension is an important manifestation of systemic lupus erythematosus (SLE) but reports of prevalence vary between 20-70% in published reports of adult and pediatric patients. For both children and adults with SLE, the clinical diagnosis and management of hypertension has traditionally been based on guidelines developed for the general population. In clinical trials, the criteria used for defining participants with hypertension are mostly undefined. As a first step towards formally assessing the blood pressure (BP) patterns of children diagnosed with SLE, 24-hr ambulatory BP monitoring data was analyzed on clinic patients who presented with prehypertension or stage I hypertension. In this pediatric SLE cohort (n=10), 20% met daytime criteria for a diagnosis of hypertension. Patterns of BP elevation varied widely with white coat, masked, isolated systolic, and diastolic nocturnal hypertension all identified. Nocturnal hypertension was detected in 60% and attenuated nocturnal BP dipping in 90% of both hypertensive and normotensive SLE patients. In SLE patients, the median nighttime systolic and diastolic loads were 25% and 15.5% compared with median daily loads of 12.5% and 11.5%. Daytime and nighttime systolic and diastolic BP load and nocturnal dipping was compared to a control population consisting of 85 non-SLE patients under 21 years old with prehypertension or stage 1 hypertension presenting to hypertension clinic. Median systolic BP dipped 5.3 mmHg in SLE patients compared to 11.9 mmHg in non-lupus ( p-value = 0.001). Median diastolic BP dipped 12.9 mmHg versus 18.5 mmHg in non-lupus ( p-value = 0.003). Patterns of BP dysregulation in pediatric SLE merit further exploration. Children with or without SLE displaying prehypertensive or stage 1 casual BP measurements had similar rates of hypertension by ambulatory BP monitoring. However, regardless of BP diagnosis, and independent of kidney involvement, there was an increased proportion with attenuated nocturnal dipping and nocturnal hypertension in SLE patients.

Nocturnal Hypertension and Attenuated Nocturnal Blood Pressure Dipping is Common in Pediatric Lupus

Hypertension is an important manifestation of systemic lupus erythematosus (SLE) but reports of prevalence vary between 20-70% in published reports of adult and pediatric patients. For both children and adults with SLE, the clinical diagnosis and management of hypertension has traditionally been based on guidelines developed for the general population. In clinical trials, the criteria used for defining participants with hypertension are mostly undefined. As a first step towards formally assessing the blood pressure (BP) patterns of children diagnosed with SLE, 24-hr ambulatory BP monitoring data was analyzed on clinic patients who presented with prehypertension or stage I hypertension. In this pediatric SLE cohort, 20% met daytime criteria for a diagnosis of hypertension. Patterns of BP elevation varied widely with white coat, masked, isolated systolic, and diastolic nocturnal hypertension all identified. Nocturnal hypertension was detected in 60% and attenuated nocturnal BP dipping in 90% of both hypertensive and normotensive SLE patients. In SLE patients, the median nighttime systolic and diastolic loads were 25% and 15.5% compared with median daily loads of 12.5% and 11.5%. Daytime and nighttime systolic and diastolic BP load and nocturnal dipping was compared to a control population consisting of 85 non-SLE patients under 21 years old with prehypertension or stage 1 hypertension presenting to hypertension clinic. Median systolic BP dipped 5.3 mmHg in SLE patients compared to 11.9 mmHg in non-lupus (p-value = 0.001). Median diastolic BP dipped 12.9 mmHg versus 18.5 mmHg in non-lupus (p-value = 0.003). Patterns of BP dysregulation in pediatric SLE merit further exploration. Children with or without SLE displaying prehypertensive or stage 1 casual BP measurements had similar rates of hypertension by ambulatory BP monitoring. However, regardless of BP diagnosis, and independent of kidney involvement, there was an increased proportion with attenuated nocturnal dipping and nocturnal hypertension in SLE patients.

PP.17.21

Objective: Most of papers about the association between earthquake and cardiovascular change have been focused on cardiovascular change of acute stress due to disaster. However, there were few reports on pressor effect after a few years of the earthquake in the suffered people. Design and method: Eight patients who were being seen for hypertension at the disaster area were in the process of performing ambulatory blood pressure (BP) monitoring when the tsunami warming (sirens) and the evacuation order on December 7th 2012, the largest aftershock of The Great East Japan Earthquake of March 11, 2011 occurred. Results: All subjects noticed that their mean systolic BP (131 ± 11 vs. 147 ± 25 mmHg, P < 0.05) was significantly elevated one hour after the aftershock, compared to one hour before the aftershock. The pulse rate profile after the aftershock in the subjects living in temporary housing was higher than that in subjects living in their own homes (69.8 ± 0.7 vs. 60.9 ± 4.9 bpm, P = 0.01). Sleep BP level (125.3 ± 11.8/71.3 ± 5.2 mmHg vs. 106.5 ± 3.4/ 61.9 ± 4.2 mmHg, both P < 0.05) and morning systolic BP level (156.5 ± 28.7 vs. 129.7 ± 1.0 mmHg, P < 0.05) were also significantly higher in the inhabitants living in the temporary housing than in those living in their own homes (Gray zone in Figure). Conclusions: The suffered people who lost their housing and still live in the temporary housing exhibited less dipping of nocturnal BP and more exaggerated morning BP surge at the time of felt aftershock 19 months after the earthquake, compared with those who live in their own home. The changes in environmental condition and life style after earthquake would alter diurnal BP variability triggered by emotional stress even after a few years.

3A.01

Objective: A blood pressure (BP) rise and sleep disturbances are known effects of high altitude exposure. Most available data have been collected at altitudes >3300m, while the possible effects of moderate altitude (MA) exposure (around 2000 m) are still poorly understood in spite of the fact that such altitude is easily reachable even by subjects suffering from cardiovascular diseases. Aim of HIGHCARE (HIGH altitude CArdiovascular REsearch)-Sestriere study was thus to evaluate the effect of exposure to an altitude of 2035m (Sestriere, Italy) on BP and sleep disturbances.Design and method: 58 healthy lowlanders were evaluated both at sea level (SL,Milan, Italy) and during acute exposure to MA (2035m, barometric pressure 80% of that at SL). 46 individuals (18 male, 28 females, age 41.52 ± 12.65y) completed the study, having conventional BP measures and 24 h ambulatory BP monitoring (ABPM, validated oscillometric TM-2430 A&D device; measurements every 15 minutes during daytime and 20 minutes during nighttime) performed both at SL and at MA. During both study conditions subjects’ daily life behaviour was carefully standardized, only light physical exercise being allowed. Results: During MA exposure mean 24 h systolic (S) and diastolic (D) BP significantly increased compared to SL (p < 0.005), with no difference between day and night (Figure1). This was the case also for mean daytime and nighttime SBP and DBP (respectively, p < 0.05) and for heart rate (p < 0.005) (Figure1). No statistically significant between-condition differences were found for conventional BP nor for nocturnal BP dipping, and there were no effects of age, gender or BMI. Low sleep quality was reported by 22% of individuals (sleep quality questionnaire), with no correlation between reported sleep quality and BP nocturnal dipping. Conclusions: Our data offer the first demonstration, in healthy subjects, that exposure to an easy-to-reach MA is associated with an increase in 24 h ambulatory BP. No changes were observed in conventional BP, further emphasizing the superior sensitivity of ABPM in assessing BP response to environmental challenges. Our results may have clinical implications for the protection of cardiovascular patients travelling to such altitude for either leisure or work.

Characterizing the temporal development of cardiovascular dysfunction in response to spinal cord injury.

Spinal cord injury (SCI) is associated with rapid and sustained impairments in cardiovascular function that ultimately cause an early onset of cardiovascular disease. We know remarkably little about the temporal progression of cardiovascular disturbances, but such an understanding is critical to inform clinical management and develop appropriate intervention strategies. To characterize the cardiovascular response to SCI, six male Wistar rats were instrumented with telemetry and assessed for continuous arterial blood pressure (BP), core body temperature, and heart rate (HR) 7 days before and up to 28 days after T3 SCI. Hemodynamic variables were averaged day by day and hour by hour. Spontaneously occurring autonomic dysreflexia (AD) was characterized by applying a novel algorithm to continuous BP and HR data, and induced AD was assessed weekly via the BP response to colorectal distension. Systolic BP was reduced at all time points after SCI compared with before SCI (p<0.003), except at 4 and 6 days post-injury. Core body temperature was reduced at 2 days post-SCI only (p=0.001). The nocturnal dip in BP and temperature observed pre-SCI was absent during the first 14 days post-SCI, but returned from 21 days post-SCI on (p<0.024). The frequency and severity of spontaneously occurring AD events were significantly less between days 6 and 10 post-SCI compared all other time points (p<0.037). The pressor response to colorectal distension was greater at 14, 21, and 28 days post-SCI compared with at 7 days post-SCI (all p<0.004). In conclusion, SCI induces rapid and profound alterations in basal hemodynamics and diurnal rhythms that partially recover by 14 days post-SCI. AD, on the other hand, is acutely present post-SCI, but the frequency and severity of AD events increase substantially from 14 days post-SCI on.

Blunted Nocturnal Blood Pressure Dipping and Exaggerated Morning Blood Pressure Surge in Response to a Novel Repetitive Sleep Restriction Challenge

The risk for cardiovascular disease increases with attenuated nocturnal blood pressure (BP) dipping and an exaggerated morning BP surge. Sleep deprivation has been associated with increased prevalence of hypertension, however, the evidence for a relationship between insufficient sleep and BP dipping/morning surge is lacking. In a 22‐day protocol, 43 healthy participants (age 32±2 yrs; BMI 24±1 kg/m2; 21 men and 22 women) were randomly assigned to 4 cycles of repeated sleep restriction (SR); (permitted 4h of sleep/night for 3 nights followed by a recovery sleep, repeated 4 times), or a sleep control (SC) group (8h/night). Beat‐to‐beat BP was recorded during six 24h periods via Portapres: baseline (BL), experimental (3rd day of each of the 4 cycles), and recovery. Mean arterial BP (MAP) dipping was calculated as [1‐ sleep MAP/wake MAP] x 100, while morning surge was determined as difference between MAP 0.5h after and 2h before wake. Nocturnal MAP dipping (19±4% in SR and 18±2% in SC, p&gt;0.05) and morning MAP surge (10±2mmHg in SR and 11±2mmHg in SC, p&gt;0.05) were not different between two groups at BL. Repetitive SR significantly blunted MAP dipping compared to SC (10±2% in SR and 16±2% in SC, P=0.02). Morning MAP surge was significantly increased in SR, but decreased in SC (15±3mmHg in SR and 8±2mmHg in SC, p=0.02). Attenuated MAP dipping reached the maximum changes from BL after the 1st SR cycle, and stabilized. Increases of morning MAP surge showed a trend of continuous rising over the 4 cycles. In conclusion, repeated SR induced significant sustained attenuation of nocturnal dipping, and increased morning surge of MAP progressively through 4 cycles. Supported by NIH (HL‐106782).