Ambulatory Blood Pressure Variability Research Articles

MO086: Sex Differences in Ambulatory Blood Pressure Trajectories and Blood Pressure Variability in Hemodialysis Patients

Abstract BACKGROUND AND AIMS Ambulatory blood pressure (BP) control is worse in men than in women with chronic kidney disease (CKD), and this may partially explain the faster CKD progression in men. The aim of this study is to investigate possible sex-differences in ambulatory BP levels, BP trajectories and BP variability (BPV) in hemodialysis patients. METHOD 129 male and 91 female hemodialysis patients that underwent 48-h ABPM with Mobil-O-Graph-NG were included in this analysis. Ambulatory BP levels over the 2-day interdialytic interval (including two daytime and two nighttime periods) were recorded. We calculated the standard deviation (SD), weighted SD (wSD), coefficient of variation (CV) and average real variability (ARV) of BP with validated formulas. RESULTS Age, dialysis vintage, antihypertensive treatment and history of major comorbidities did not differ between men and women. Pre-dialysis SBP levels did not differ between men and women (145.1 ± 22.7 versus 145.9 ± 25.7 mmHg, P = 0.808), but DBP was marginally higher in men (87.6 ± 14.0 versus 84.0 ± 13.7 mmHg, P =0.055). About 48-h SBP/DBP (137.2 ± 17.4/81.9 ± 12.1 mmHg versus 132.2 ± 19.2/75.9 ± 11.7 mmHg, P = 0.045/<0.001) as well as DBP during the first and SBP/DBP during the second 24-h period were significantly higher in men than in women. Similarly, daytime SBP/DBP was significantly higher in men (138.3 ± 17.5/83.2 ± 12.3 mmHg versus 131.9 ± 19.4/76.4 ± 11.5 mmHg, P = 0.011/<0.001). No significant between-group differences were detected for nighttime SBP. All SBP variability indices were similar between men and women; DBP-SD, DBP-wSD and DBP-ARV were higher in men (44-h DBP-ARV 9.4 ± 1.8 versus 8.6 ± 1.9, P = 0.002). No significant differences were revealed in the dipping pattern between men and women. CONCLUSION Ambulatory BP levels and trajectories, as well as DBP variability indices are higher in men than women hemodialysis patients. This worse ambulatory BP profile in male compared to female patients may impact on the incidence of cardiovascular events.

MO081: Ambulatory Blood Pressure Trajectories and Blood Pressure Variability in Kidney Transplant Recipients: A Comparative Study Against Chronic Kidney Disease Patients

Abstract BACKGROUND AND AIMS Hypertension is a major cardiovascular risk factor in both kidney transplant recipients (KTRs) and patients with chronic kidney disease (CKD). Ambulatory blood pressure monitoring (ABPM) is considered the gold standard method for hypertension management in these subjects. This is the first study evaluating in comparison the full ambulatory BP profile and short-term BP variability (BPV) in KTRs versus CKD patients without kidney replacement therapy. METHOD 93 KTRs were matched with 93 CKD patients for age, sex and eGFR. All participants underwent 24 h ABPM; mean ambulatory BP levels, BP trajectories and BPV indices [standard deviation (SD), weighted-SD and average real variability] were compared between the two groups. RESULTS There were no significant between-group differences in 24-h SBP/DBP (KTRs:126.9 ± 13.1/79.1 ± 7.9 versus CKD:128.1 ± 11.2/77.9 ± 8.1 mmHg, P = 0.522/0.293), daytime SBP/DBP and nighttime SBP; nighttime DBP was slightly higher in KTRs (KTRs:76.5 ± 8.8 versus CKD:73.8 ± 8.8 mmHg, P = 0.040). For both ambulatory SBP/DBP, repeated-measurements-ANOVA showed a significant effect of time (SBP: F = [19, 3002]=11.735, P < 0.001, partial η2 = 0.069) but not of KTR/CKD status (SBP: F = [1, 158] = 0.668, P = 0.415, partial η2 = 0.004). Ambulatory systolic/diastolic BPV indices were not different between KTRs and CKD patients, except for 24-h DBP-SD that was slightly higher in the latter (KTRs: 10.2 ± 2.2 versus CKD: 10.9 ± 2.6 mmHg, P = 0.041). No differences were noted in dipping pattern between the two groups. CONCLUSION Mean ambulatory BP levels, BP trajectories and short-term BPV indices are not significantly different between KTRs and CKD patients, suggesting that KTRs have a similar ambulatory BP profile compared with CKD patients without kidney replacement therapy.

MO087: Ambulatory Blood Pressure Trajectories and Blood Pressure Variability in Kidney Transplant Recipients: A Comparative Study Against Hemodialysis Patients

Abstract BACKGROUND AND AIMS Hypertension is the most prevalent cardiovascular risk factor in kidney transplant recipients (KTRs). Preliminary data suggest similar ambulatory blood pressure (ΒP) levels in KTRs and hemodialysis (HD) patients. This is the first study evaluating in comparison the full ambulatory BP profile and short-term BP variability (BPV) in KTRs versus HD patients. METHOD Two hundred four KTRs were matched (2:1 ratio) with 102 HD patients for age and gender. BP levels, BP trajectories and BPV indices over a 24-h ambulatory BP monitoring (ABPM) in KTRs were compared against both the first and second 24-h period of a standard 48-h ABPM in HD. To evaluate the effect of renal replacement treatment and time on ambulatory BP levels, two-way-ANOVA for repeated-measurements was performed. RESULTS KTRs had significantly lower SBP and pulse-pressure (PP) levels compared with HD during all periods studied (24-h SBP: KTR: 126.5 ± 12.1 mmHg; HD first 24-h: 132.0 ± 18.1 mmHg, P = 0.006; second 24-h: 134.3 ± 17.7 mmHg, P < 0.001); no significant differences were noted for DBP levels with the exception of second nighttime. Repeated-measurements-ANOVA showed a significant effect of RRT modality and time on ambulatory SBP levels during all periods studied, and a significant interaction between-them; the greatest between-group difference in BP (KTRs—HD in mmHg) was observed at the end of the second 24-h (−13.9 mmHg, 95%CI: −21.5 to −6.2, P < 0.001). Ambulatory systolic and diastolic BPV indices were significantly lower in KTRs than in HD during all periods studied (24-h SBP-ARV: KTRs: 9.6 ± 2.3 mmHg; HD first 24-h: 10.3 ± 3.0 mmHg, P = 0.032; second 24-h: 11.5 ± 3.0 mmHg, P < 0.001). No differences were noted in dipping pattern between the two groups. CONCLUSION SBP and PP levels and trajectories, and BPV were significantly lower in KTRs compared to age- and gender-matched HD patients during all periods studied. These findings suggest a more favorable ambulatory BP profile in KTRs, in contrast with previous observations.

Twenty-four-hour and nocturnal ambulatory blood pressure variability patterns in diabetics and hypothyroid patients: Looking through different temporal windows

ABSTRACT This cross-sectional study attempted to determine the 24-h blood pressure variability (BPV) and nocturnal dipping, through designated temporal windows in diabetic and hypothyroid patients. BPV profiles were examined in the cohorts of 26 diabetics and 27 hypothyroid patients on their prescribed medications. Fifty-seven (57) healthy normotensive subjects were treated as controls. We recorded blood pressure (BP)parameters in each subject over at least two to three consecutive days, using an ambulatory blood pressure monitor (ABPM). We analyzed the data employing A&D software, Cosinor rhythmometry, and SPSS software. Most of the patients displayed a statistically significant circadian rhythm with prominent periodsat 24 h and/or 12 h. The hourly-averaged data in patients exceeded the normal range of BP during the early morning and late afternoon. BP parameters in studied patients were significantly higher than in the controls. The results depicted significant and independent effects of “temporal window” and “disease” on the nocturnal BP profile. Higher BPV and bouts of nocturnal hypotension in diabetic and hypothyroid patients indicate poor BP management. The diagnosis of BP and efficacy of treatment in diabetic and hypothyroid patients could be detected proficiently by ambulatory BP monitoring. Temporal window analysis could be beneficial for tracing nocturnal dipping precisely.

Relationship Between Ambulatory Blood Pressure Variability and Atherogenic Index of Plasma

Relationship Between Ambulatory Blood Pressure Variability and Atherogenic Index of Plasma

Ambulatory Blood Pressure Variability after Adenotonsillectomy in Childhood Sleep Apnea.

To investigate the influence of adenotonsillectomy (T&A) on ambulatory blood pressure (BP) variability in children with obstructive sleep apnea (OSA). Prospective, interventional study. Children with OSA symptoms were recruited from a tertiary center. After OSA diagnosis was confirmed (ie, apnea-hypopnea index [AHI] > 1), these children underwent T&A for treatment. We performed polysomnography and 24-hour recordings of ambulatory BP before and 3 to 6 months postoperatively. Ambulatory BP variability was presented as the standard deviation of mean blood pressure in the 24-hour monitoring of ambulatory BP. Differences in BP variability among different subgroups were tested using a multivariable linear mixed model. A total of 190 children were enrolled (mean age: 7.8 ± 3.3 years; 73% were boys; 34% were obese). The AHI significantly decreased from 12.3 ± 17.0 to 2.7 ± 5.5 events/hr after T&A. Overall, daytime, and nighttime ambulatory BP did not significantly change postoperatively, and overall, daytime, and nighttime ambulatory BP variability did not differ significantly preoperatively and postoperatively. In the subgroup analysis, children aged <6 years demonstrated a significantly greater decrease in ambulatory BP variability postoperatively than those aged >6 years (nighttime diastolic BP variability: 9.9 to 7.7 vs. 8.9 to 9.4). Children with hypertension also showed a significantly greater decrease in ambulatory BP variability than those without hypertension. We concluded that overall ambulatory BP variability does not significantly change after T&A in children with OSA. Moreover, young-aged and hypertensive children demonstrate a significant decrease in BP variability after T&A. 4 Laryngoscope, 132:2491-2497, 2022.

E-Selectin Is Associated with Daytime and 24-Hour Diastolic Blood Pressure Variability in Type 2 Diabetes.

E-selectin is an endothelial cell adhesion molecule involved in vascular inflammation. Elevated E-selectin has been reported in patients with high blood pressure and diabetes. Given the increasing clinical relevance of parameters derived from ambulatory blood pressure monitoring, further investigation of their relationships with E-selectin is of interest. In this study, we aimed to investigate the association between serum E-selectin, office blood pressure and 24 h ambulatory blood pressure parameters in patients with type 2 diabetes. Blood pressure variability was assessed by computing the standard deviation of mean systolic and diastolic blood pressure separately for daytime and nighttime during 24 h ambulatory blood pressure monitoring in a cohort of patients with type 2 diabetes (n = 132). Additionally, were assessed nighttime systolic dipping and pulse pressure separately for daytime, nighttime, and 24 h. Serum E-selectin was measured using the enzyme-linked immunosorbent assay technique. We found that E-selectin was consistently associated with 24 h diastolic blood pressure variability (r = 0.238; p = 0.019) and daytime diastolic blood pressure variability (r = 0.258; p = 0.012), after adjustment for confounding factors. No association of E-selectin with office blood pressure and other 24 h ambulatory blood pressure parameters was observed. In conclusion, endothelial activation indicated by elevated serum E-selectin is associated with increased ambulatory diastolic blood pressure variability in patients with type 2 diabetes.

Effects of isometric leg training on ambulatory blood pressure and morning blood pressure surge in young normotensive men and women

Despite the reported association between diurnal variations in ambulatory blood pressure (BP) and elevated cardiovascular disease risk, little is known regarding the effects of isometric resistance training (IRT), a practical BP-lowering intervention, on ambulatory BP and morning BP surge (MBPS). Thus, we investigated whether (i) IRT causes reductions in ambulatory BP and MBPS, in young normotensives, and (ii) if there are any sex differences in these changes. Twenty normotensive individuals (mean 24-h SBP = 121 ± 7, DBP = 67 ± 6 mmHg) undertook 10-weeks of bilateral-leg IRT (4 × 2-min/2-min rest, at 20% maximum voluntary contraction (MVC) 3 days/week). Ambulatory BP and MBPS (mean systolic BP (SBP) 2 h after waking minus the lowest sleeping 1 h mean SBP) was measures pre- and post-training. There were significant reductions in 24-h ambulatory SBP in men (− 4 ± 2 mmHg, P = 0.0001) and women (− 4 ± 2 mmHg, P = 0.0001) following IRT. Significant reductions were also observed in MBPS (− 6 ± 8 mmHg, p = 0.044; − 6 ± 7 mmHg, P = 0.019), yet there were no significant differences between men and women in these changes, and 24-h ambulatory diastolic BP remained unchanged. Furthermore, a significant correlation was identified between the magnitude of the change in MBPS and the magnitude of changes in the mean 2-h SBP after waking for both men and women (men, r = 0.89, P = 0.001; women, r = 0.74, P = 0.014). These findings add further support to the idea that IRT, as practical lifestyle intervention, is effective in significantly lowering ambulatory SBP and MBPS and might reduce the incidence of adverse cardiovascular events that often occur in the morning.

Ambulatory blood pressure trajectories and blood pressure variability in kidney transplant recipients: a comparative study against haemodialysis patients.

ABSTRACTBackgroundHypertension is the most prevalent cardiovascular risk factor in kidney transplant recipients (KTRs). Preliminary data suggest similar ambulatory blood pressure (BP) levels in KTRs and haemodialysis (HD) patients. This is the first study comparing the full ambulatory BP profile and short-term BP variability (BPV) in KTRs versus HD patients.MethodsA total of 204 KTRs were matched (2:1 ratio) with 102 HD patients for age and gender. BP levels, BP trajectories and BPV indices over a 24-h ambulatory BP monitoring (ABPM) in KTRs were compared against both the first and second 24-h periods of a standard 48-h ABPM in HD patients. To evaluate the effect of renal replacement treatment and time on ambulatory BP levels, a two-way ANOVA for repeated measurements was performed.ResultsKTRs had significantly lower systolic blood pressure (SBP) and pulse-pressure (PP) levels compared with HD patients during all periods studied (24-h SBP: KTR: 126.5 ± 12.1 mmHg; HD first 24 h: 132.0 ± 18.1 mmHg; P = 0.006; second 24 h: 134.3 ± 17.7 mmHg; P < 0.001); no significant differences were noted for diastolic blood pressure levels with the exception of the second nighttime. Repeated measurements ANOVA showed a significant effect of renal replacement therapy modality and time on ambulatory SBP levels during all periods studied, and a significant interaction between them; the greatest between-group difference in BP (KTRs–HD in mmHg) was observed at the end of the second 24 h [–13.9 mmHg (95% confidence interval –21.5 to –6.2); P < 0.001]. Ambulatory systolic and diastolic BPV indices were significantly lower in KTRs than in HD patients during all periods studied (24-h SBP average real variability: KTRs: 9.6 ± 2.3 mmHg; HD first 24 h: 10.3 ± 3.0 mmHg; P = 0.032; second 24 h: 11.5 ± 3.0 mmHg; P < 0.001). No differences were noted in dipping pattern between the two groups.ConclusionsSBP and PP levels and trajectories, and BPV were significantly lower in KTRs compared with age- and gender-matched HD patients during all periods studied. These findings suggest a more favourable ambulatory BP profile in KTRs, in contrast to previous observations.

Effects of isometric handgrip training on blood pressure among hypertensive patients seen within public primary healthcare: a randomized controlled trial.

Meta-analyses have demonstrated that isometric handgrip training (IHT) decreases blood pressure in hypertensive individuals. Nonetheless, most studies were conducted in laboratory settings and its effects in real-world settings remain unclear. To analyze the effects of IHT on office and ambulatory blood pressure in hypertensive patients attended within primary healthcare. Randomized controlled trial conducted in primary healthcare units within the Family Health Program, Petrolina, Pernambuco, Brazil. 63 hypertensive patients (30-79 years old; 70% female) were randomly allocated into IHT or control groups. IHT was performed three times per week (4 x 2 minutes at 30% of maximal voluntary contraction, one-minute rest between bouts, alternating the hands). Before and after the 12-week training period, office and ambulatory blood pressure and heart rate variability were obtained. The significance level was set at P < 0.05 (two-tailed testing) for all analyses. IHT significantly decreased office systolic blood pressure (IHT: 129 ± 4 versus 121 ± 3 mmHg, P < 0.05; control: 126 ± 4 versus 126 ± 3 mmHg, P > 0.05), whereas there was no effect on diastolic blood pressure (IHT: 83 ± 3 versus 79 ± 2 mmHg, P > 0.05; control: 81 ± 3 versus 77 ± 3 mmHg, P > 0.05). Heart rate variability and ambulatory blood pressure were not altered by the interventions (P > 0.05 for all). IHT reduced office systolic blood pressure in hypertensive patients attended within primary care. However, there were effects regarding diastolic blood pressure, ambulatory blood pressure or heart rate variability. NCT03216317.

Efeito agudo do Mat Pilates sobre a variabilidade da pressão arterial ambulatorial em mulheres após a menopausa

Introdução: Após a menopausa mulheres tem maior risco de desenvolver doenças cardiovasculares. A prática de exercício físico é um dos tratamentos para e redução da incidência dessas doenças, e o método Pilates consiste em um programa completo de condicionamento físico. Objetivos: Verificar as respostas da Monitorização Ambulatorial da Pressão Arterial (MAPA) e da Variabilidade da Pressão Arterial após uma única sessão de Mat Pilates em mulheres após a menopausa não obesas. Métodos: Este é um estudo cruzado randomizado com 15 mulheres pós-menopáusicas normotensas, que participaram de uma única sessão de Mat Pilates e de uma sessão de controle. A sessão de Pilates durou 50 minutos, com 5 minutos de aquecimento. Em cada exercício, houve 1 série de 10 repetições com 45 segundos de descanso entre as séries. A sessão controle teve a mesma duração, mas as voluntárias permaneciam sentadas. A MAPA foi avaliada durante 24 horas após a intervenção. Estatística: Utilizou-se ANOVA de dois fatores com post hoc de Newman-Keuls para análise das variáveis da MAPA e teste t de Student para análise da variabilidade de pressão arterial. Resultados: Não houve diferença significativa (p &lt;0,05) nas respostas da pressão arterial sistólica e diastólica durante 24h, vigília e sono ou em sua variabilidade entre as sessões de Pilates e Controle. Conclusão: O Mat Pilates não reduziu os valores pressóricos da MAPA ou sua variabilidade em mulheres após a menopausa não obesas.

Ambulatory blood pressure variability measures in hypertensive patients according to non-alcoholic fatty liver disease state

Abstract Background Nonalcoholic fatty liver disease (NAFLD) represents the most frequent cause of chronic hepatic disease and independently determines hypertension and future cardiovascular events. Increased blood pressure variability (BPV) assessed by 24-hour blood pressure (BP) monitoring including mean arterial morning surge have been also associated with increased rates of cardiovascular events. Purpose To compare different BPV measures in hypertensive patients with and without NAFLD. Methods Consecutive newly diagnosed untreated hypertensive patients without history of cardiovascular disease underwent clinic and ambulatory BP measurements. NAFLD was diagnosed by liver ultrasound to separate patients into those with and without NAFLD. BPV was derived by assessment of standard deviation (SD) of systolic and diastolic BP (24-h, daytime and nighttime), average real variability (ARV) of systolic and diastolic BP, coefficient of variation (CV) of systolic BP (24-h, daytime), weighted SD (wSD) of systolic BP (24-h, daytime), maximum BP and mean arterial morning surge. Results Among 146 hypertensive patients (mean age 57±11 years, 64 men, 24-h mean systolic/diastolic BP 140±10/84±9 mmHg) those with NAFLD (n=76) compared to the non-NAFLD group (n=70) were younger (54.7±10.1 vs 58.6±11.2 years, respectively, p=0.03), male gender was more prevalent (42 vs 22 respectively, p=0.004), and body mass index was more increased (33.2±4.1 vs 27.0±3.5 kg/m2, p&amp;lt;0.001). Moreover, NAFLD patients compared to those without NAFLD were characterized by higher levels of mean arterial pressure morning surge (12.4±8.9 vs 8.7±8.5 mmHg, p=0.03), but the remaining BPV measures were not different between the two groups. NAFLD was a determinant of both diastolic BP ARV (B=0.34, p=0.007) and mean arterial morning surge (B=0.47, p=0.006) after adjustment. Conclusions Mean arterial pressure morning surge was significantly higher in hypertensive patients with NAFLD compared to their non-NAFLD counterparts, while whole day BPV measures were not increased in NAFLD except for ARV of diastolic BP. Our findings may partially explain the increased cardiovascular risk of comorbid NAFLD in hypertension. Funding Acknowledgement Type of funding sources: None.

Sex Differences in Post-exercise Hypotension, Ambulatory Blood Pressure Variability, and Endothelial Function After a Power Training Session in Older Adults.

Background: The efficacy of power training (PT) to acutely reduce blood pressure (BP) in participants with hypertension is controversial, and no studies have assessed the influence of sex on post-exercise hypotension and its mechanisms in older adults.Purpose: The aims of this secondary, exploratory analysis were to compare the effects of a single bout of PT on post-exercise hypotension, BP variability, and endothelial function between older men and women with hypertension.Methods: Twenty-four participants with hypertension (12 men and 12 women aged to >60 years old) took part in this crossover study and randomly performed two experimental sessions: power exercise training (PT) and non-exercising control session (Con). The PT protocol was composed of 3 sets of 8–10 repetitions of five exercises performed in the following order: leg press, bench press, knee extension, upright row, and knee flexion, using an intensity corresponding to 50% of one repetition maximal test (1RM) and 2-min intervals between sets and exercises. The concentric phase of exercises during each repetition was performed “as fast as possible,” while the eccentric phase lasted 1 to 2 s. During Con, the participants remained at seated rest on the same exercise machines, but without any exercise. Each protocol lasted 40 min. Office BP, flow-mediated dilatation (FMD), 24-h ambulatory BP, and the average real variability (ARV) of systolic and diastolic BP were assessed before and after experimental sessions.Results: Comparing PT with Con, a reduced office BP after exercise was found in men (systolic BP—average post 1 h: −14 mmHg, p < 0.001; diastolic BP—average post 1 h: −8 mmHg, p < 0.001) and only a reduced systolic BP in women (average post 1 h: −7 mmHg, p = 0.04). Comparing men and women, a reduced systolic BP (post 60': −15 mmHg, p = 0.048; average post 1 h: −7 mmHg, p = 0.046) and diastolic BP (post 60': −9 mmHg, p = 0.049) after the first hour were found in men. In relation to 24-h ambulatory BP, ARV, and FMD, no statistically significant differences were found between men and women.Conclusion: In older adults with hypertension, the office BP response after the experimental sessions was different in men and women, showing that the PT protocol is more effective to acutely reduce BP in men. Additionally, the mechanisms behind this reduction remain unclear. This finding suggests that sex cannot be combined to analyze post-exercise hypotension.Clinical Trial Registration: ClinicalTrials.gov, Identifier: NCT03615625.

Office, Central, and Ambulatory Blood Pressure for Predicting First Stroke in Older Adults: A Community-Based Cohort Study.

[Figure: see text].

Effect of Antihypertensive Drugs on Circadian Variation of Blood Pressure Measured by Ambulatory Blood Pressure Monitoring in Controlled Hypertensive Individuals

Background: Rewinding back a 100 years ago, Riva Rocci introduced the meticulous way of measuring blood pressure (BP) in clinical practice. With recent years, ambulatory BP monitoring came into existence which is still not used routinely in the management of hypertension. This thought led to the commencement of our study to analyze the variations in ambulatory BP recording over a 24-h cycle. Objectives: The objectives of the study are to determine the BP differences throughout the circadian cycle and to analyze the variations in circadian rhythm due to various antihypertensive drugs. Methods: On the first visit to the Medicine Outpatient Department, patient's medical history was recorded. Three readings of office BP were recorded using a sphygmomanometer. The patient was then provided with the ambulatory BP monitoring device, sent home and asked to follow-up after 24 h and the report was recorded. Results: On comparing the nocturnal pattern among candidates taking single versus combination drug, the dip was found to be in 31.7% in patients on single drug compared to 38.6% combination therapy. The surge in BP was seen in 56.8% of patients on single-drug therapy compared to 43.3% patients on combination drug therapy. Conclusion: Single-drug therapy for hypertension did not show a significant nocturnal pattern compared to the combination drug therapy for hypertension. The presence of the risk factors such as obesity smoking, dyslipidemia, diabetes mellitus, hypothyroidism, family history, and chronic kidney disease showed a presence of dipping and nondipping pattern in BP.

Augmented pressor responses to individual bursts of muscle sympathetic nerve activity in human obesity

Obesity is associated with increased sympathetic outflow and hypertension. However, it remains unclear whether the systemic pressor response to spontaneous bursts of sympathetic nerve activity (i.e., sympathetic transduction) is augmented in obesity. Therefore, we tested the hypothesis that transduction of muscle sympathetic nerve activity (MSNA) to arterial blood pressure (BP) is significantly higher in obese vs. lean adults. Also, because obesity alters regulation of BP over the 24-hour period, we further examined the extent to which sympathetic transduction is associated with ambulatory 24-hour BP variability (standard deviation). MSNA (microneurography) and arterial BP (finger cuff) were measured continuously for 10 min under resting conditions in 20 young/middle-age obese participants and 20 age- and sex-matched lean controls. Signal averaging was used to characterize beat-by-beat changes in mean arterial pressure (MAP) for 15 cardiac cycles following each MSNA burst. MSNA was not significantly elevated in obese vs. lean participants (25±11 vs. 21±10 bursts/min, P=0.27). However, transduction of MSNA to BP was significantly elevated in obese vs. lean participants when considering multiple successive bursts (P<0.01) and all bursts (P<0.01). Similarly, increases in burst amplitude evoked greater MAP responses with obese having the largest peak increases (3.8±1.7 vs. 2.7±1.6 mmHg, P=0.03). Multiple regression indicated that sympathetic transduction was a significant determinant of 24-hour MAP variability (β=0.47, P<0.01), independent of age, BMI, MSNA, and 24-hour MAP (all P>0.05). These findings demonstrate that transduction of MSNA to BP is augmented in human obesity. Sympathetic transduction also appears to contribute to higher BP variability independent of obesity.

A COMPARATIVE STUDY OF AMBULATORY BLOOD PRESSURE LEVELS, TRAJECTORIES AND SHORT-TERM BLOOD PRESSURE VARIABILITY IN DIABETIC AND NON-DIABETIC PATIENTS WITH CKD STAGE 2, 3A, 3B AND 4

Objective: Diabetic kidney disease is the leading cause of end-stage renal disease worldwide. Whether diabetes mellitus (DM) is an additional factor leading to elevated blood pressure (BP) levels and BP variability (BPV) in patients with chronic kidney disease (CKD) is unknown. This study aimed to compare ambulatory BP levels, BP trends and BPV in diabetic and non-diabetic patients with CKD. Design and method: This study included 48 diabetic and 48 non-diabetic adult patients (&gt;18 years) with CKD (eGFR: &lt; 90 and &gt;15 mL/min/1.73m2), matched in a 1:1 ratio for age, sex and eGFR within each CKD stage (2, 3a, 3b and 4). All patients underwent 24-hour ambulatory BP measurement with the Mobil-O-Graph device. To evaluate the effect of diabetes and time on the trajectories of 24-hour BP levels, we performed two-way mixed ANOVA analysis for repeated measurements using hourly means. BPV was calculated using standard deviation (SD), weighted SD (wSD), coefficient of variation (CV) and average real variability (ARV) of BP during the 24-hour, day- and night-time periods. Results: In total, patients with DM had significantly higher 24-hour systolic BP (SBP) (132.13 ± 10.71 vs 124.16 ± 11.45 mmHg, p = 0.001) and similar 24-hour diastolic BP (DBP) (75.00 ± 8.43 vs 74.62 ± 6.86 mmHg, p = 0.809) compared to patients without DM. A similar trend was evident across all CKD stages. The effect of DM on BP trajectories during the recording period was significant for SBP [F = 18.766, p &lt; 0.001, partial h2 = 0.261] and marginally significant for DBP [F = 3.782, p = 0.057, partial h2 = 0.067]. 24hour SBP SD, wSD and ARV (10.94 ± 2.75 vs 9.46 ± 2.10, p = 0.004), as well as 24hour DBP SD, wSD, CV and ARV (8.23 ± 2.10 vs 7.10 ± 1.32, p = 0.002) were significantly higher in diabetic compared to non-diabetic CKD patients. Conclusions: Ambulatory SBP levels are higher and SBP-profile is different in patients with diabetic compared to those with non-diabetic CKD. Systolic and diastolic BPV are also higher in diabetic subjects. These findings may signify a higher cardiovascular risk of diabetic CKD patients.

AMBULATORY BLOOD PRESSURE PROFILE AND BLOOD PRESSURE VARIABILITY IN PERITONEAL DIALYSIS COMPARED TO HEMODIALYSIS AND CHRONIC KIDNEY DISEASE PATIENTS

Objective: Hypertension in ESRD patients is highly prevalent and poorly controlled. Data on ambulatory blood pressure (BP) profile and BP variability (BPV) in peritoneal dialysis (PD) patients are absent. This study examined the BP profile and BPV of patients undergoing PD in comparison to hemodialysis (HD) and pre-dialysis CKD patients. Design and method: Thirty-eight PD patients were matched for age, gender and dialysis vintage with 76 HD patients and for age and gender with 38 patients with CKD stage 2–4. Patients under PD and HD underwent 48-hour and CKD patients 24-hour ambulatory BP monitoring. BP levels and BPV indexes were compared for the 48hour, 1st and 2nd 24hour, daytime and nighttime periods. Two-way mixed ANOVA analysis for repeated measurements was used to evaluate the effect of dialysis modality and time on ambulatory BP in PD and HD. Results: During all periods studied, SBP and DBP were numerically higher but not statistically different in PD than in HD patients. Systolic BP was significantly higher in PD or HD compared with predialysis CKD (PD:138.38 ± 20.97; HD:133.75 ± 15.5; CKD:125.52 ± 13.4, p = 0.003), a difference evident also during daytime and night-time periods. Repeated-measurements analysis showed no effect of dialysis modality on ambulatory BP during all periods studied. All BPV indexes studied were similar between PD and HD patients and higher than CKD individuals (1st-24hour systolic-ARV: PD: 11.86 ± 3.19; HD:11.23 ± 3.45; CKD:9.81 ± 2.49, p = 0.016). Conclusions: Average BP levels and BPV indices are similar between PD and HD patients and higher compared to CKD counterparts. The dialysis modality has no effect on ambulatory BP profile. These results suggest that PD is no better than HD with regards to overall BP control or BP fluctuations over time.

AMBULATORY BLOOD PRESSURE MONITORING: ADVANTAGES AND OPPORTUNITIES

Objective: Ambulatory Blood Pressure Monitoring (ABPM) is a procedure used to diagnose hypertension, detect white-coat effect, masked hypertension and monitor blood pressure (BP) control. It offers additional and important data in opposite to office BP, such as the dipping status and circadian variability of ambulatory BP, and it is a better predictor of cardiovascular outcomes and morbid or fatal events. In our country, ABPM has limited availability in Primary Health Care. With that in mind, the health care team of our Primary Health Care Unit created an ABPM protocol in August 2017 in order to provide this procedure to its patients. Design and method: Descriptive, cross-sectional and observational study. Data collected from August 2017 to December 2019 regarding the results of ABPM and patient data. The ABPM protocol was designed following the most recent European Society of Hypertension guidelines. Results: In the described period, our unit performed 136 ABPM exams. The average age of patients submitted to ABPM was 53 years and 54% were of the male gender. The majority (67%) were referred for diagnosis purposes and 33% to monitor BP control. With the ABPM protocol we were able to diagnose 60 patients with sustained hypertension and 36 patients with uncontrolled hypertension, from which 10 presented resistant hypertension. Regarding the dipping status, 55% were dipper, 23% extreme dipper, 19% non-dipper and 3% reverse dipper. In 63% of cases, the ABPM results led to direct clinical decision-making by the family physician, such as pharmacology intervention, clinical investigation and lifestyle advice. Conclusions: Overall the ABPM is an accurate, cost-effective protocol that provides important information for the prediction of cardiovascular risk. Consequently, ABPM protocol implementation has been observed to have a direct positive impact in the diagnosis, monitoring and clinical decision-making ability of the physician regarding hypertension. With this presentation we wish to share the positive impact of ABPM usage on our Health Care Unit and to inspire and motivate others to create a similar protocol.

NEW CONCEPT OF TRIGGER-SPECIFIC BLOOD PRESSURE SENSITIVITY “THERMOSENSITIVITY” MEASURED BY ICT-BASED MULTISENSOR ABPM IN PATIENTS WITH HEART FAILURE

Objective: A sudden elevation of blood pressure (BP) by cold temperatures in winter is widely recognized as one of causes in exacerbation of heart failure. A reactivity of BP against changes in temperature in ambulatory setting remains unclear in patients with heart failure. We assessed the BP reactivity against changes of temperature using a newly developed device ICT-based Multisensor Ambulatory BP Monitoring (IMS-ABPM) in patients with heart failure. Design and method: The IMS-ABPM has accelerometer, thermometer and atmospheric barometer, which enable to measure physical activity, temperature and atmospheric pressure with measuring ambulatory BP. In this study, we evaluated trigger-specific BP sensitivity according to the ambulatory BP reactivity based on the slope of BP change against the triggers using the IMS-ABPM, which was “thermosensitivity” defined as the slope of BP change against temperature in the BP measurement. This study was a cross-sectional study to assess relationship between “thermosensitivity” and cardiac function by using IMS-ABPM in patients who had been admitted to a medical facility due to heart failure. Results: Among 103 patients with heart failure (mean ± SD age, 76.4 ± 14.4 years; 47.6% men), 55.6% of patients was heart failure with preserved ejection fraction (HFpEF). Although mean 24-hour systolic BP level and ambulatory BP variability evaluated coefficient of variation, average real variability had not significant difference between patients with HFpEF and heart failure with reduced ejection fraction (HFrEF), the thermosensitivity was significantly lower (hyperthermosensitive) in patients with HFpEF compared to HFrEF (HFpEF, –1.59 ± 3.22 vs. HFrEF, 0.08 ± 4.14, p = 0.038). After adjusted age and sex, the thermosensitivity was significantly associated with HFpEF. Moreover, the thermosensitivity tended to be correlated with ejection fraction in echocardiography (r = –0.21, p = 0.052 in Spearman's correlation). Conclusions: Based on the results of this study, patients with HFpEF showed lower thermosensitivity (hyperthermosensitive), which suggested BP strongly elevated with cold temperature, compared to patients with HFrEF. The new concept of trigger-specific BP sensitivity “thermosensitivity” might be associated with the exacerbation of heart failure in HFpEF.