Diurnal Blood Pressure Research Articles

Short- to long-term blood pressure variability: Current evidence and new evaluations.

Increased blood pressure (BP) variability and the BP surge have been reported to be associated with increased cardiovascular risk independently of BP levels and can also be a trigger of cardiovascular events. There are multiple types of BP variation: beat-to-beat variations related to breathing and the autonomic nervous system, diurnal BP variation and nocturnal dipping related to sleep and physical activity over a 24-hr period, day-to-day BP variability with anomalous readings within a several-day period, visit-to-visit BP variability between outpatient visits, and seasonal variations. BP variability is also associated with the progression to hypertension from prehypertension and the progression of chronic kidney disease and cognitive impairments. Our research group proposed the "resonance hypothesis of blood pressure surge" as a new etiological hypothesis of BP variability and surges; i.e., the concept that when the time phases of surges and hypertension-inducing environmental influences coincide, resonance occurs and is amplified into a larger "dynamic surge" that triggers the onset of cardiovascular disease. New devices to assess BP variability as well as new therapeutic interventions to reduce BP variability are being developed. Although there are still issues to be addressed (including measurement accuracy), cuffless devices and information and communication technology (ICT)-based BP monitoring devices have been developed and validated. These new devices will be useful for the individualized optimal management of BP. However, evidence regarding the usefulness of therapeutic interventions to control BP variability is still lacking.

PS-C16-14: EFFECT OF THE COVID-19 PANDEMIC ON AMBULATORY BLOOD PRESSURE MEASUREMENT

Introduction: The world is currently facing the fourth wave of the COVID-19 pandemic. The aim of this study is to assess the effect of this pandemic on ambulatory blood pressure measurements (ABPM) and to investigate the effect of SARS-CoV2 infection on blood pressure (BP). Methods: We conducted a uni-centric retrospective study on the ERASME hospital ABPM register, from 2010 to 2021. The nycthemeral blood pressure (BP) profile of the pandemic period (January 2020 to October 2021) was compared with that of the previous 5 control periods from January 2010 to October 2019. We also determined the diurnal, nocturnal and 24-hour high blood pressure frequencies for each period. Furthermore, for the COVID-19 period, the BP profiles of COVID-19 positive and negative patients were compared. Finally, in COVID-19 positive patients, we compared ABPMs performed before COVID-19 infection with those performed post-infection. Results: After excluding incomplete and poor-quality ABPM, 16,977 ABPMs were selected. The COVID-19 period accounted for 10.58% of ABPMs compared with 15–20% for pré-COVID periods. We observed that diurnal (83.20 vs 81.20; p < 0.001), nocturnal (73.02 vs 71.09; p < 0.001) and 24-hour (79.51 vs 77.50; p < 0.001) diastolic BPs were higher in the COVID-19 period. In contrast, diurnal (131.64 vs 133.18; p < 0.001), nocturnal (121.07 vs 121.93; p = 0.034) and 24-hour (127.82 vs 128.97; p < 0.001) systolic BPs were lower during the pandemic. In logistic regression, diastolic diurnal (OR:1.58 [1.33–1.89]; p < 0.001), nocturnal (OR:1.18 [1.02 - 1.36]; p = 0.026) and 24-hour (OR:1.22 [1.01 - 1.49]; p = 0.044) hypertension were associated with the COVID-19 period, when adjusted for age, gender or history of hypertension. Also, diurnal (OR:0.63 [0.55–0.71]; p < 0.001) and nocturnal (OR:0.82 [0.72–0.93]; p = 0.002) systolic hypertension were less frequent in the COVID-19 period. When comparing BPs between COVID-19 positive and negative patients, there was no significant difference. When ABPMs were compared before and after infection in COVID-19 positive patients, diastolic diurnal (88.41 vs. 78.88; p = 0.001), nocturnal (77.91 vs. 70.55; p = 0.027) and 24-hour (84.57 vs. 75.99; p = 0.002) BPs were higher after COVID-19 infection. Conclusion: Our study shows that during the COVID-19 pandemic, diastolic BP was higher and systolic BP was lower compared to the pre-COVID-19 period. We also observed an increase in diastolic BP after COVID-19 infection.

PS-C25-11: PILATES AS AN ALTERNATIVE METHOD OF EXERCISE TO LOWER BLOOD PRESSURE IN WOMEN WITH SYSTEMIC HYPERTENSION: A SCIENTIFIC LITERATURE REVIEW

Objective: This review aimed at studying the effects of Pilates as an alternative method of exercise on blood pressure in women with hypertension. Design and Methods: A systematic literature search was performed as per the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines 2020. Databases searched were PubMed (MEDLINE), Scopus, Cumulative Index to Nursing and Allied Health Literature (CINAHL), Cochrane Trial Registry and Database, Physical Therapy Evidence Database (PEDro) applying keywords as pilates, mat pilates, blood pressure, hypertension, elevated blood pressure, systemic hypertension, women. Filters applied were studies published between (01/01/2002 up to 25/06/2022), randomized, non-randomized clinical trials and English language. The Boolean operators used were AND, OR, NOT. Eligibility criteria: The articles selected for data synthesis required the following criteria for inclusion: Population: women with systemic hypertension, Intervention: Pilates in any mode of administration (Mat, Reformer, Cadillac, Barrel) Comparison group: Control group that has not undergone Pilates training, Outcomes: Arterial blood pressure parameters measured using both mercurial, oscillometric sphygmomanometers, Study Design: Randomized or non-randomized clinical trials. Results: A total of 137 records were retrieved from the databases (Cochrane Reviews and Trials Registry (n = 6), PubMed (MEDLINE) (n = 23), CINAHL (n = 13), Scopus (n = 90) and PEDro (n = 5). Deduplication was implemented using the Mendeley® software version yielding a total of 126 records. Records were further excluded based on eligibility (differences in target population: pregnancy, normotensive women, diabetes mellitus, cardiac disease, obesity, pulmonary disease, cancer, mental health, reviews, registered trial protocols and others). The included records (n = 7) were screened (title, abstract and full text) for eligibility by two independent reviewers. Data extraction and synthesis was done using Rayyan® software for systematic reviews by two independent reviewers regulated by a third senior reviewer. Quality assessment of each article was done using the Jadad® Scale for quality of evidence provided in each article. Out of the 7 studies selected, 3 studies were randomized controlled clinical trials. Significant reduction in systolic, mean arterial blood pressures was reported (n = 5). Diastolic blood pressure did not significantly change with Pilates training (n = 3). Reduction in ambulatory blood pressures, diurnal blood pressures were reported (n = 3). Pilates training was either administered using mats (n = 5) or equipments (n = 2) in combination with aerobic exercise or alone (n = 1). Conclusion: Systolic and mean arterial blood pressure have been found to be significantly lowered with Mat Pilates or equipment based Pilates in combination or alone in pre and postmenopausal women with hypertension.

S-37-1: PROGNOSTIC UTILITY OF MORNING BLOOD PRESSURE SURGE

Morning blood pressure surge (MBPS), defined as the difference between morning systolic blood pressure and the lowest nighttime systolic blood pressure, is a normal physiological phenomenon of diurnal blood pressure variability (BPV). Exaggerated MBPS is associated with morning hypertension and has been associated with adverse cardiovascular and cerebrovascular events, especially hemorrhagic stroke. However, MBPS has low reproducibility and there is an ethnic difference in the amplitude of MBPS and its prognostic value. More evidence is needed to prove its clinical usefulness in the management of hypertension. Since the risk of MBPS is mainly attributable to the elevated morning blood pressure, the focus therefore has shifted from MBPS to the control of morning hypertension. Because MBPS focuses only on the amplitude rather than the rate of blood pressure rise, we calculated the MBPS rate as the slope of linear regression of sequential systolic blood pressure measures on the time intervals within the MBPS period. We found the reproducibility for the MBPS rate was better than the MBPS amplitude. The MBPS rate was a more sensitive and reliable prognostic factor of long term mortality than the MBPS amplitude. The prognostic values of MBPS rate were comparable in subjects with or without morning and nocturnal hypertension. Because the MBPS rate can easily be calculated from the ambulatory blood pressure monitoring data, it could become a routine parameter in daily practice in conjunction with other routinely derived parameters including MBPS amplitude.

PS-R06-3: A CASE OF CEREBRAL INFARCTION IN AN ELDERLY HYPERTENSIVE PATIENT WITH 24-HOUR STRICT BLOOD PRESSURE CONTROL

Introduction: In elderly patients, hypertension is a major risk factor of stroke. Therefore, strict blood pressure (BP) control provides most effective for the prevention of stroke incidence. Here, we report the case of stroke occurred under strict BP control in an elderly patient. Case: A 80-year-old Japanese women with the treatment of hypertension and dyslipidemia was admitted to our hospital with suddenly vertigo. Before admission, her BP control was controlled, which her ambulatory BP monitoring performed three months prior to admission showed that 24-hour, daytime and nighttime BP were 107/61 mmHg, 112/64 mmHg and 94/53 mmHg, respectively, and diurnal BP variation showed dipper pattern. On admission, her electrocardiography showed sinus rhythm, and her head magnetic resonance imaging showed the bilateral cerebellum infarction, which is the area dominated by posterior inferior cerebellar artery. The D-dimer level was 1.2 μg/ml. Transesophageal echocardiography was performed to search for an embolic source of stroke and revealed a patent foramen ovale (PFO). Leg vein echocardiography showed the thrombus in the bilateral soleus veins. Based on the above results, we diagnosed a paradoxical cerebral embolism caused by deep vein thrombosis of the lower extremities and PFO. Conclusion: The patient had achieved strict BP control assessed by ABPM prior to the onset of the stroke and was considered to be at low risk of stroke. Paradoxical cerebral embolism is a common cause of stroke in younger patients, however, physicians should be also noted as a cause of cerebral infarction even in the elderly patients.

S-58-2: CUFFLESS WEARABLE 24-HOUR BLOOD PRESSURE MONIT ORING VERSUS STANDARD AMBULATORY MONITORING

Objective: Cuffless wearable blood pressure (BP) monitors have great potential in assessing 24-hour BP without user disturbance for weeks and months. However, it is uncertain whether these devices can accurately track BP changes during usual daily activities and sleep as with standard 24-hour ambulatory BP monitoring (ABPM). We assessed daytime and nighttime BP using a commercially available cuffless wearable BP device versus classic ABPM. Design and method: We included 45 individuals (age 58 ± 14 years [mean ± SD], 33% female, 80% hypertensive) in two centres (Perth, Australia; Athens, Greece). Participants used a cuffless wearable BP monitor (Aktiia, Switzerland) continuously for 7–10 days and 24-hour ABPM (MicroLife WatchBP O3, Switzerland) on the first and the last day of cuffless BP monitoring. Daily 24-hour, daytime, and nighttime BP values were averaged across the total study days for the cuffless device and across the two ABPM days. Results: The cuffless device reported higher systolic BP for 24-hours by 6.8 mmHg, 95%CI [3.7, 9.7], daytime by 3.8 mmHg [1.0, 6.7], and nighttime by 17.5 mmHg [13.6, 21.4] (all p < 0.01). Cuffless 24-hour diastolic BP was comparable with ABPM (difference 1.2 mmHg, 95%CI [-1.0, 3.5]), as was daytime diastolic BP (-0.8 mmHg [-3.0, 1.3]) (both p. < 27). However, the cuffless device reported higher nighttime diastolic BP by 9.2 mmHg, 95%CI [6.3, 12.2] (p < 0.001). Nighttime dip as measured by the cuffless device, namely systolic BP (-5.1 mmHg, 95%CI [-13.7, 3.6]) and diastolic BP (-3.8 mmHg [-11.6, 4.2]) were substantially less than ABPM (systolic BP dip: -18.0 mmHg [-35.5, -1.2]; diastolic BP dip: -13.8 mmHg [-27.2, -0.8]). The cuffless device identified 44 nighttime non-dippers (defined as a relative dip < 10%) for systolic BP and 42 non-dippers for diastolic BP, compared to 10 non-dippers for both systolic and diastolic BP as identified by ABPM (both comparisons p < 0.001). Conclusions: The Aktiia cuffless wearable BP device considerably overestimated average systolic BP compared to classic ABPM and was unable to adequately track diurnal BP variation.

Abstract 15380: Cardiac Localized Polycystin 2 is Required for Natriuretic Peptide Production and Its Absence is a Main Driver of Hypertension

Introduction: Autosomal Dominant Polycystic Kidney Disease (ADPKD) occurs in 1:1000 births and causes renal cysts and loss of renal function. However, cardiovascular complications are the most common cause of mortality in ADPKD patients and hypertension affects 70% of patients before decline in renal function. ADPKD arises from mutations in PKD1 and PKD2, encoding Polycystin 1 and Polycystin 2 (PC2) respectively. PC2 forms a nonselective cation pore channel that conducts calcium. Heterozygous mice for Pkd2 have attenuated natriuretic peptide (NP) responses. The NPs, ANP and BNP, are regulators of euvolemia via renal excretion of sodium following cardiac atrial and ventricular stretch, thought to be a calcium activated process. We hypothesized cardiac PC2 contributes to NP production and loss of PC2 induces hypertension without renal involvement. Methods: Cardiomyocyte inducible PC2 KO (PC2 cKO) mice were generated by crossing Pkd2 floxed mice with αMHC-MerCreMer mice. Cardiomyocyte Cre expression was induced by tamoxifen diet at 6 weeks. Mice were aged to 7 months and had intra-aortic blood pressure monitoring or left ventricular tissue collection for quantitative PCR (qPCR) analysis. Male and female mice (n=4-9) were used and analyzed separately by Student’s t-Test, with a p <0.05 considered statistically significant. Results: PC2 cKO mice had elevated diurnal blood pressure (160/110mmHg) without renal cysts. Comparisons were made to age-matched controls. All reported genes were affected in males and females, with only female data reported (Mean ± SEM). qPCR analysis showed that PC2 cKO mice had a ~50% decrease in Nppa (WT: 1± 0.2 KO: 0.6 ± 0.1) and Nppb (WT: 1 ± 0.1 KO: 0.5 ± 0.2) mRNA, genes encoding ANP and BNP respectively. There was a ~60% reduction in Pcsk6 (WT: 1 ± 0.1, KO: 0.4 ± 0.1) mRNA in PC2 cKO mice, a gene encoding a protease necessary for Corin activity, regulating ANP. Cgb mRNA was abolished (WT: 1 ± 0.2, KO: 0.03 ± 0.01) in PC2 cKO mice, encoding Chromogranin B, a regulator of NF-κB mediated production of Nppb mRNA and ANP-containing vesicles. Conclusion: We conclude loss of PC2 in cardiomyocytes leads to a hypertensive phenotype which may arise from a calcium-dependent multi-component dysfunction of cardiomyocyte NP production.

Association of Ambulatory Blood Pressure and Other Factors With Intraocular Pressure-Related 24-Hour Contact Lens Sensor Profile in Untreated Glaucoma.

PurposeTo investigate the association of diurnal blood pressure (BP) and other factors with the intraocular pressure (IOP)–related 24-hour contact lens sensor (CLS) profile of patients with untreated glaucoma.MethodsThe prospective study included 82 patients with untreated normal-tension glaucoma. CLS measurements and ambulatory BP monitoring were performed simultaneously for 24 hours. The association between the mean arterial pressure (MAP) and CLS profile was examined for the daytime and nocturnal periods using linear regression analysis. The associations between other factors and the CLS profile were also examined.ResultsMultivariate analysis of data from 63 eligible patients showed that higher average MAPs were significantly associated with larger average nocturnal CLS values (β coefficient = 0.273; P = 0.023); a larger increase in the last CLS value (β coefficient = 0.366; P = 0.003); larger standard deviations (SDs) of CLS values for the daytime, nocturnal, and 24-hour periods (β coefficient = 0.407, 0.293, and 0.375; P < 0.001, P = 0.032 and 0.002, respectively); and higher average ocular pulse frequencies for the daytime, nocturnal, and 24-hour periods (β coefficient = 0.268, 0.380, and 0.403; P = 0.029, 0.002, and 0.001, respectively). Thicker subfoveal choroids and shorter axial length were significantly associated with larger SDs and larger average CLS values, respectively. Smaller anterior chamber volume and lower corneal hysteresis were associated with larger SDs or larger average ocular pulse amplitude.ConclusionsAmbulatory BP and several ocular parameters were significantly associated with various parameters of the 24-hour CLS profile.Translational RelevanceAmbulatory BP and ocular parameters may be modifiers of the 24-hour IOP-related profile of CLS.

Diurnal changes in blood pressure and heart rate in children with narcolepsy with cataplexy.

The hypocretin neurons in the lateral hypothalamus are connected not only to brain alertness systems but also to brainstem nuclei that regulate blood pressure and heart rate. The premise is that regulation of blood pressure and heart rate is altered and affected by methylphenidate, a stimulant drug in children with narcolepsy with cataplexy. The changes in 24-hr ambulatory systolic and diastolic blood pressure and heart rate were compared among pre-treated narcolepsy with cataplexy patients (40 males, 10 females), with mean age 10.4 ± 3.5 years (M ± SD, range 5-17 years) with values from 100 archival age-sex-body mass index matched controls. Patients had a lower diurnal systolic blood pressure (-6.5 mmHg; p=0.000) but higher heart rate (+11.0bpm; p=0.000), particularly evident in the waketime, while diastolic blood pressure was comparable. With methylphenidate (18 mg sustained release at 08:00 hours), patients with narcolepsy with cataplexy had higher systolic blood pressure (+4.6 mmHg, p=0.015), diastolic blood pressure (+3.3 mmHg, p=0.005) and heart rate (+7.1bpm, p=0.028) during wake time, but nighttime cardiovascular values were unchanged from pre-treated values; amplitude variation in cardiovascular values was unchanged over 24 hr. In conclusion, children with narcolepsy with cataplexy had downregulation blood pressure profile but a higher heart rate, and lesser non-dipping profiles. Daytime methylphenidate treatment increases only waketime blood pressure and further elevated heart rate values.

The relationship between nondipper hypertension and triglyceride glucose index.

Nondipper hypertensive patients have an increased incidence of damage to end organs, including the brain, heart, and kidney, and a worse cardiovascular prognosis. The triglyceride glucose (TyG) index is a reliable indicator of insulin resistance (IR) and is closely related to the traditional risk factors of cardiovascular disease. To the best of our knowledge, whether there is a relationship between the TyG index and impaired diurnal blood pressure (BP) has not been investigated. This study aimed to compare the TyG index between normotensive, nondipper, and dipper hypertensive patients. A total of 1037 patients grouped according to the results of ambulatory BP monitoring were included, with group 1 including dipper hypertensive ( n = 368), group 2 including nondipper hypertensive ( n = 496), and group 3 including normotensive control ( n = 173) patients. In both the univariate and multivariate logistic regression analyses, TyG index [odds ratio (OR), 4.656; 95% confidence interval (CI), 3.014-7.193; P < 0.001], age (OR, 1.011; 95% CI, 1.002-1.021; P = 0.018), and glomerular filtration rate (GFR) (OR, 0.979; 95% CI, 0.971-0.987; P < 0.001) were independent predictors of nondipper hypertension (HT). In the ROC analysis, a TyG index cutoff value of at least 4.74 predicted nondipper hypertensive patients with a sensitivity of 59.7%, and a specificity of 59.9% [area under the curve = 0.647 (0.614-0.680); 95% CI; P < 0.001]. We showed that TyG index, age, and GFR are independent predictors in patients with nondipper HT. TyG index, a simple, cost-effective, and rapid tool can predict the nondipper pattern in essential HT.

Clinical Efficacy of Combined Use of Azilsartan with Indapamide and Azilsartan with Nitrendipine in Patients with Arterial Hypertension

The aim of our study was a comparative evaluation of the effectiveness of the combined use of azilsartan with indapamide, and azilsartan with nitrendipine in achieving antihypertensive and organ-protective effects in patients with arterial hypertension (AH). Methods and Results: The study included 101 patients aged 30-75 years (mean age of 53,1±11,2 years) with AH Grades 1-2 (ESC/ESH, 2018), who were on outpatient treatment at the Republican Specialized Scientific and Practical Medical Center for Cardiology. After the screening stage, all patients were discontinued from previous therapy and assigned to the 2 regimes of dual therapy. Group 1 included 50 AH patients treated with azilsartan (Az) and indapamide (Ind); Group 2 included 51 patients treated with Az and nitrendipine (Nit). The average daily dose of Az was 49.3±6.0 mg, Nit - 10.88±4.3 mg, and Ind - 1.69±0.5 mg. The effectiveness of the prescribed therapy was evaluated after 6 months of treatment. The 6-month dual therapy with Az+Ind and Az+Net is characterized by high antihypertensive efficacy with a significant positive effect on the parameters of diurnal blood pressure (BP) profile in AH patients. Achieving the target level of BP in both groups provided high organ-protective efficacy, expressed in a significant regression of LV hypertrophy and LV dimensions, a decrease in the carotid intima-media thickness (CMIT) and arterial rigidity. However, the best cardio- and vaso-protective efficacy was noted in Group 1, which was expressed in a more pronounced improvement in the left ventricular diastolic function, a decrease in the CIMT on both sides, and a significant improvement in the parameters of central hemodynamics and arterial stiffness. Dual therapy with Az+Ind and Az+Nit in AH patients was accompanied by a positive effect on the metabolic profile and excellent nephroprotection, with an advantage in the Az+Ind group. A significant decrease in the blood level of LDL-C, TC, and uric acid is characteristic in both groups of patients. A significant decrease in the levels of FBG and TG occurs only in the Az+Ind therapy.

Abstract P232: Endothelin B Receptor Modulation Of Diurnal Blood Pressure Amplitude During High Salt Diet

High salt diet can alter baroreflex sensitivity. We have previously shown that rats deficient in endothelin B receptors (ET B -R) demonstrate an exaggerated diurnal blood pressure amplitude similar to that seen in rats with sinoaortic denervation fed a high salt diet. However, it remains unclear if ET B -R influence on baroreflex function is due to sensory or efferent mechanisms of autonomic blood pressure control. We employed selective ET B -R antagonism using A192621 in ET B -R deficient rats (ET B -def) that only express functional ET B -R on efferent nerves and transgenic controls (TG) to isolate the role of efferent vs sensory pathways. Rats with telemetry were fed a normal salt diet (0.49% NaCl) during baseline and osmotic minipump infusion of 10 mg/kg/day A192621 or vehicle. After one week of infusion, animals were fed a high salt (4.0% NaCl) diet. Selective ET B -R blockade increased 24 hr MAP in TG animals during normal salt diet (+16.4 ± 1.0 mmHg from baseline; n = 10; p &lt; 0.001) but had no effect on ET B -def (-1.2 ± 1.8 mmHg; n = 7; p &gt; 0.99 ). A192621 treated TG rats did not exhibit a further increase in pressure following high salt diet (+5.5 ± 1.3 mmHg; n = 6; p = 0.25), but both vehicle and A192621 treated ET B -def rats displayed a salt-sensitive increase in MAP (+15.9 ± 4.2 and +14.4 ± 4.5 mmHg; n = 3 and 4; p = 0.003 and 0.001, respectively). A192621 treatment had no significant effect on MAP amplitude (light-dark difference) in any group during normal salt diet. However, during high salt, A192621 treated TG animals had an increase in MAP amplitude (+9.7 ± 0.7 mmHg; n = 6; p = 0.002), and vehicle had no effect (+0.8 ± 0.8 mmHg; n = 5; p = 0.97). Both A192621 and vehicle treated ET B -def rats had a similar increase in amplitude following high salt diet (+9.3 ± 0.6 and +8.6 ± 1.4; n = 4 and 3; p = 0.001 and 0.018, respectively). In summary, antagonism of ET B -R increased MAP only in TG rats but did not have an effect on diurnal amplitude during normal salt in any group. Antagonism of ET B -R during high salt diet caused TG rats to exhibit a similarly high diurnal amplitude as ET B -def rats. These data suggest that blocking ET B -R on baroreflex sensory pathways are the mitigating cause for increased diurnal blood pressure rhythms during high salt diet.

Inter-individual Variability To Two Modes Of Resistance Training In The Blood Pressure Dipping Response In Males

The 24-h blood pressure (BP) in response to an acute bout of resistance training exercise (RTE) varies between individuals and has received little attention in the literature, especially in the changes in BP occurring during sleep (i.e., dipping). PURPOSE: To determine the inter-individual BP dipping variability of normotensive (NT) and hypertensive (HT) individuals completing two modalities of a single session of RTE. METHODS: Volunteers were 41 males (NT n = 21, age = 19.7 ± 2.3 yr., weight = 72.5 ± 17.3 kg, height = 171.0 ± 5.0 cm, HT n = 22, age = 21.7 ± 4.6 yr., weight = 78.1 ± 11.0 kg, height = 174.0 ± 5.0 cm) who underwent a non-exercise control (CTRL), RTE low-repetitions high-sets (LRHS), and RTE high-repetitions low-sets (HRLS) conditions. The 24-h ambulatory monitoring recorded diurnal and nocturnal systolic (SBP) and diastolic (DBP) BP. Factorial ANOVA compared SBP and DBP dipping responses in NT and HT individuals. Inter-individual responses were obtained by comparing diurnal and nocturnal BP differences. The technical error of measurement (TEM) and the smallest worthwhile change (SWC) were used to compute a BP threshold to identify responders and non-responders. RESULTS: No significant group by measurement interaction was found on SBP (p = 0.301) and DBP (p = 0.574). Diurnal SBP was lower in the NT than in the HT groups (M = 117.4 ± 6.4 vs. 132.0 ± 8.2 mmHg, p ≤ 0.0001, η2 = 0.51). Diurnal DBP was lower in the NT than in the HT groups (M = 70.5 ± 6.2 vs. 77.7 ± 7.7 mmHg, p = 0.0001, η2 = 0.22). Nocturnal SBP was lower in the NT than in the HT groups (M = 106.6 ± 7.2 vs. 119.5 ± 8.3 mmHg, p ≤ 0.0001, η2 = 0.42). Nocturnal DBP was lower in the NT than in the HT groups (M = 60.4 ± 5.7 vs. 66.1 ± 8.2 mmHg, p = 0.014, η2 = 0.14). The dipping responders for SBP in the CTRL condition were 71.4% for NT and 70.0% for HT, in the HRLS condition were 66.7% for NT and 60.0% for HT, and in the LRHS condition were 57.1% for NT and 60.0% for HT. The dipping responders for DBP in the CTRL condition were 57.1% for NT and 60.0% for HT, in the HRLS condition were 61.9% for NT and 70.0% for HT, and in the LRHS condition were 71.4% for NT and 65.0% for HT. CONCLUSION: The inter-individual SBP dipping responders were similar between RTE modalities; however, for DBP, there were more HT responders than NT individuals completing a single session of HRLS RTE.

Abstract 079: Long-term Circadian Disruption Via Food Availability Leads To Kidney Damage

Circadian disruption (CD) is a risk factor in cardiovascular disease although we know little about its effects on the kidney. Previous work from our group showed that short-term CD in mice by restricting food availability to the daytime is sufficient to invert diurnal blood pressure rhythms yet kidney excretory function remained aligned with the light-dark cycle. Thus, we hypothesize that long-term CD will result in kidney damage. After putting C57BL/6 mice on a regular 12:12 light:dark cycle were placed on an inactive time-restricted feeding (iTRF, 12h food access during the day/lights on) or ad libitum feeding protocol for 8 weeks. During the final week, male and female iTRF mice ate significantly less during the 24-hour day compared to ad lib feeding (male iTRF 6.1±1.4g/day vs. ad lib 9.1±0.9g/day, p&lt;.0001, n=9 for both groups; female iTRF 6.4 ±0.7 g/day, vs. ad lib 8.3±1.5g/day, p&lt;0.01, n=9 and 8, respectively). Both sexes had an inversion in their diurnal water intake rhythms but maintained normal diurnal urinary water excretion. Aldosterone (aldo) and endothelin-1 (ET-1) contribute to circadian timing of sodium transport systems in the collecting duct. While male iTRF mice maintained their diurnal rhythm of aldosterone excretion (2.0±1.4ng/hr in light, p=0.06; 7.8±3.1ng/hr in dark, p=0.37, n=6), female iTRF mice lost their diurnal rhythm (4.4±2.7ng/hr in light, p=0.85; 4.4±3.1ng/hr in dark, p=0.11, n=6). Male mice with iTRF had significantly lower ET-1 excretion, but maintained the diurnal variation. In contrast, female iTRF mice demonstrated an inverted ET-1 excretion pattern (18.5±6.3ng/hr in light vs. 7.3±2.9ng/hr in dark, p=0.03, n=3) compared to ad lib fed mice (18.9±2.1ng/hr in light vs. 33.7±5.6ng/hr in dark, p=0.01, n=3). Picrosirus red staining of kidneys revealed a striking increase in glomerular and interstitial fibrosis in iTRF male mice as compared to their ad lib counterparts. In contrast, iTRF female mice appeared to be completely protected from increased fibrosis. These results support our hypothesis that long-term CD due to timing of food intake exacerbates kidney damage. However, females were protected against renal fibrosis, perhaps due in part to an ability to better modulate kidney rhythms in response to food timing.

Abstract 088: Comparison Of 24-hour Blood Pressure Tracking Between A Commercially Available Cuffless Wearable Device And Standard Ambulatory Monitoring

Introduction: Cuffless blood pressure (BP) monitoring offers great potential in assessing 24-hour BP without user disturbance. Despite the myriad of commercially available cuffless BP devices, it is uncertain whether these devices can accurately track BP changes during usual daily activities and sleep as with standard 24-hour ambulatory BP monitoring (ABPM). Hypothesis: A commercially available cuffless wearable BP device, previously demonstrated to have good accuracy for seated BP, can track 24-hour BP changes as well as standard ABPM. Methods: We included 45 individuals (36 hypertensive, 15 female, age 58±14 years [mean±SD]) in two centres (Perth, Australia; Athens, Greece). Participants used a cuffless wearable BP device (Aktiia, Switzerland) continuously for 7-10 days and 24-hour ABPM (MicroLife WatchBP O3, Switzerland) on the first and the last day of cuffless BP monitoring. Daily 24-hour, daytime, and nighttime BP values were averaged across the total study days for the cuffless device and across the two ABPM days. Results: Compared to ABPM, the cuffless device reported higher 24-hour systolic BP (SBP) by 6.8 mmHg, 95% CI [3.7, 9.7], higher daytime SBP by 3.8 mmHg [1.0, 6.7], and higher nighttime SBP by 17.5 mmHg [13.6, 21.4] (all p≤0.01). Cuffless 24-hour diastolic BP (DBP) was comparable with ABPM (difference 1.2 mmHg, 95% CI [-1.0, 3.5]), as was daytime DBP (difference -0.8 mmHg, [-3.0, 1.3]) (both p≥0.27), but nighttime DBP was higher by 9.2 mmHg, [6.3, 12.2] (p&lt;0.001). Nighttime dip in SBP (-5.1 mmHg, 95% CI [-13.7, 3.6]) and DBP (-3.8 mmHg, [-11.6, 4.2]) as measured by the cuffless device were substantially less than ABPM (SBP dip: -18.0 mmHg, [-35.5, -1.2]; DBP dip: -13.8 mmHg, [-27.2, -0.8]). The cuffless device identified 44 nighttime non-dippers (defined as a relative dip &lt; 10%) for SBP and 42 non-dippers for DBP, compared to 10 non-dippers for both SBP and DBP as identified by ABPM (both comparisons p&lt;0.001). Conclusions: A commercially available cuffless wearable BP device was unable to adequately track diurnal BP variation and considerably overestimated average SBP over 24 hours as compared to standard ABPM.

Abstract P098: Association Between Postpartum Sleep Characteristics And Twenty-four Hour Blood Pressure Patterns In Women With And Without A History Of Preeclampsia

Introduction: Women with a history of preeclampsia (hxPE), a hypertensive pregnancy disorder, are at a four-fold elevated risk of chronic hypertension postpartum compared with healthy pregnancy. The postpartum period is particularly vulnerable to adverse sleep characteristics such as poor sleep quality and frequent sleep disturbances, which are associated with hypertension risk. However, the relation between postpartum sleep characteristics, nighttime blood pressure (BP) and diurnal BP variation assessed by twenty-four hour ambulatory BP monitoring is not well-studied. Methods: Women with a hxPE (N=13, age 37 ± 5 years) and healthy pregnancy controls (N=12, 36 ± 3 years) without history of sleep disorders were enrolled between 1-5 years postpartum (2.9 ± 1.3 years). Subjective sleep characteristics were reported using the Pittsburgh Sleep Quality Index (PSQI). Ambulatory BP monitoring was conducted to measure 24-hour, day and night BP as well as nocturnal BP dipping and morning BP surge quantified by sleep-trough surge. Results: Women with a hxPE tended to report poorer global sleep quality (7 ± 3 vs 5 ± 3 PSQI score, P=0.09) related to more frequent sleep disturbance (8 ± 4 vs 5 ± 3 score, P=0.053) without differences in habitual sleep duration (7 ± 1 vs 7 ± 1 hours, P=0.37) or sleep latency (18 ± 11 vs 17 ± 9 min, P=0.89). In the entire group, frequency of sleep disturbance was associated with greater 24-hour BP (systolic: r = 0.42, P=0.046; diastolic: r = 0.43, P=0.04) but not night BP (systolic: r = 0.19, P=0.40; diastolic: r = 0.19, P=0.40). Only sleep latency was related to blunted nocturnal BP dipping % (r = -0.38, P=0.08), and no sleep characteristics were associated with augmented morning BP surge. Conclusions: Women with a hxPE reported poorer overall sleep quality compared with healthy pregnancy controls 1-5 years postpartum, particularly frequent sleep disturbances. Frequency of sleep disturbance was associated with elevated 24-hour BP, but not higher nighttime BP or attenuated nocturnal BP dipping, indicating that the impact of postpartum sleep characteristics on BP is not attributable to diurnal BP variation.

Hypertension in kidney transplant recipients.

Kidney transplantation is considered the treatment of choice for end-stage kidney disease patients. However, the residual cardiovascular risk remains significantly higher in kidney transplant recipients (KTRs) than in the general population. Hypertension is highly prevalent in KTRs and represents a major modifiable risk factor associated with adverse cardiovascular outcomes and reduced patient and graft survival. Proper definition of hypertension and recognition of special phenotypes and abnormal diurnal blood pressure (BP) patterns is crucial for adequate BP control. Misclassification by office BP is commonly encountered in these patients, and a high proportion of masked and uncontrolled hypertension, as well as of white-coat hypertension, has been revealed in these patients with the use of ambulatory BP monitoring. The pathophysiology of hypertension in KTRs is multifactorial, involving traditional risk factors, factors related to chronic kidney disease and factors related to the transplantation procedure. In the absence of evidence from large-scale randomized controlled trials in this population, BP targets for hypertension management in KTR have been extrapolated from chronic kidney disease populations. The most recent Kidney Disease Improving Global Outcomes 2021 guidelines recommend lowering BP to less than 130/80 mmHg using standardized BP office measurements. Dihydropyridine calcium channel blockers and angiotensin-converting enzyme inhibitors/angiotensin-II receptor blockers have been established as the preferred first-line agents, on the basis of emphasis placed on their favorable outcomes on graft survival. The aim of this review is to provide previous and recent evidence on prevalence, accurate diagnosis, pathophysiology and treatment of hypertension in KTRs.

Left ventricular global function index and peculiarities of daily blood pressure profile in patients with arterial hypertension

BACKGROUND: The left ventricular global function index (LVGFI), determined using transthoracic echocardiography, is a simple clinical marker of left ventricular dysfunction and has superior prognostic value to the standard ejection fraction-based assessment of cardiac pump function. The methodology for calculating this index was proposed in 2019. Currently, the clinical factors that influence the state of left ventricular global functions are not examined.&#x0D; AIM: This study aimed to assess the association of LVGFI with the peculiarities of daily blood pressure (BP) profile in patients with arterial hypertension (AH).&#x0D; MATERIALS AND METHODS: A total of 104 patients [51 men (49%) and 53 (51%) women] with AH were examined. The mean age of the patients was 58.711.73 years, and disease duration was 6.0310.93 years. AH corresponded to grades 1, 2, and 3 in 47 (45.2%), 26 (25.0%), and 31 (29.8%) patients, respectively. Patients with myocardial infarction or stroke, cardiomyopathies, heart defects, diabetes mellitus, thyroid dysfunction, or chronic kidney disease were not included in the study. All patients underwent daily BP monitoring, echocardiography, carotid artery examination, and biochemical blood tests.&#x0D; RESULTS: A significant inverse weak correlation of LVGFI with age (r=0.215, p=0.028), body mass index (r=0.378, p=0.001), BP variability (r=0.307, p=0.002), and daily mean values of systolic (r=0.223, p=0.026) and diastolic (r=0.237, p=0.018) BP were observed. In the regression analysis, an increase in body mass index, abnormal diurnal BP with excessive BP reduction at night, and high BP variability demonstrated a significant and independent association with decreased LVGFI.&#x0D; CONCLUSIONS: The study revealed an independent association of decreased LVGFI with increased body mass index, excessive BP reduction at night, and high systolic BP variability. These factors should be considered in the possible development of a strategy to prevent target organ damage in AH.

EFFECT OF THE COVID-19 PANDEMIC ON THE NYCHTHEMERAL BLOOD PRESSURE PROFILE

Objective: The world is currently facing the fourth wave of the COVID-19 pandemic. The purpose of this study was to assess the effect of this pandemic on ambulatory blood pressure measurements and to compare the blood pressure profile between COVID-19 positive and negative patients. Design and method: We performed a unicentric, retrospective study on the register of ambulatory blood pressure measurements (ABPM) of the ERASME Hospital from 2010 to 2021. ABPMs performed during the pandemic period (January 2020 to October 2021) were compared with those from 5 previous control periods. In order to improve the comparison of the different periods, we considered variations (delta) of each period from the previous 3 months. For all patients whose ABPM was performed during the COVID-19 period, we looked for COVID test results preceding the ABPM. These patients were classified into 2 groups COVID positive, if at least one PCR or serological test was positive, and COVID negative if not. Data analysis was performed using SPSS version 23.0. Results: After exclusion of incomplete and poor-quality ABPMs, 18766 were retained, of which 1796 (9.57%) were for the COVID-19 period. The control periods represented 14.77% to 18.81% of the MAPAs in the study. We observed that diurnal, nocturnal and 24-hour diastolic blood pressures (BP) were higher in the COVID-19 period than in the previous 5 periods ranging from January 2010 to October 2019. Pulse pressure was lower in the COVID-19 period compared to the previous periods. Of the 1796 patients in the COVID-19 period, pre-ABPM COVID-19 status were obtained from 368 patients, 322 negatives and 46 positives. In COVID-19 positive patients, daytime systolic BP was higher than in COVID-19 negative patients (88,41 ± 11,74 vs 84,63 ± 12,24; p = 0.047). Also, the pulse pressure of COVID-19 positive patients was lower (44,46 ± 7,72 vs 47,57 ± 8,84). No significant differences were observed between the two groups for the other parameters. Conclusions: The COVID-19 pandemic resulted in increased daytime and night-time diastolic blood pressures. Also, this study suggests an increase in diurnal diastolic blood pressure after COVID-19 infection.

Readings of 24-hour ambulatory blood pressure monitoring (ABPM) in patients with stage II arterial hypertension (HTN) receiving planned antihypertensive therapy

The aim of the study:to analyze ABPM readings in patients with stage II HTN receiving antihypertensive therapy in order to plan a personalized algorithm for managing HTN patients at the stage of the outpatient care. Materials and methods. 60 patients with stage II HTN were examined. ABPM readings were assessed on the background of planned antihypertensive therapy (ARBs and diuretics) and after the adjustment of the therapy (perindopril and amlodipine).Results. The use of long period monitoring provides comprehensive information about the patterns of blood pressure changesthroughout the day. Patients with stage II HTN receiving planned antihypertensive therapy with ARBs and diuretics did not have targeted BP during the day and had a systolic HTN of stage I, while there was a statistically significant increase in BP variability during the day and in the readings indicating a hypertensive load of target organs in comparison with a group of patients receiving a combination of perindopril and amlodipine for 3 months. In addition, there was a statistically significant (ANOVA, p&lt;0.05) difference in the rate of morning BP rise, which can serve as a precursor for the development of cardiovascular events in the morning compared to the group of patients with theadjusted therapy. Among hypertensive patients receiving ARBs and diuretics a disturbed circadian rhythm predominated in the structure of the diurnal BP profilecompared with the patients who received combined therapy with perindopril and amlodipine. In addition, the proportion of night-peakers among patients taking ARBs and diuretics was 2 times higher than among patients whose therapywas adjusted 3 months ago.Conclusion. Thus, in the group of patients whose antihypertensive therapy was timely adjusted, there was an improvement in hemodynamics: due to the achievement of targeteddiurnal blood pressurereadings, a significant decrease in BP variability during the day and the rate of the morning rise in blood pressure, as well as the proportion of patients with a normal diurnal blood pressure profileincreased.