Nighttime Blood Pressure Research Articles

STUDY OF EARLY RETINAL CHANGES IN PATIENTS WITH NEWLY DIAGNOSED TYPE 2 DIABETES MELLITUS

Objective: Retina and endothelium constitute fields in which the hyperglycemia’s pathological effects of type 2 diabetes mellitus (T2DM) can be detected. However, the precise time of these lesions’ appearance and factors contributing to it are still under investigation. Thus, we studied the early retinal lesions and endothelial function in patients with a recent diagnosis of T2DM (<6 months) and their association with adverse prognostic factors. Design and method: Patients with a recent diagnosis of T2DM receiving no other diabetic medication except from Metformin, and volunteers matched for age and blood pressure (BP) participated in the study. Somatometric data, BP measurements (ambulatory and office) and hematological parameters (lipids, renal function, fasting glucose, glycosylated hemoglobin) were recorded. Endothelial function was assessed by Asymmetric Dimethylarginine (ADMA). Retinal vessel diameters (central retinal arteriolar equivalent-CRAE / central retinal venular equivalent-CRVE) and their ratio (arteriovenous ratio-AVR) were assessed with a non-mydriatic fundus camera using special software. Results: We studied 165 participants, 81 T2DM patients and 84 non-T2DM volunteers. No differences were found between the 2 groups in retinopathy and ADMA measurements. ADMA was associated with female sex (p = 0.037), Body Mass Index (p = 0.033) and AVR (p = 0.047). AVR was significantly associated with age, male sex, ADMA, estimated Glomerular Filtration Rate (eGFR), smoking, office, day and nighttime diastolic, 24-hour, and nighttime systolic BP. Linear regression analysis showed the independent correlation of AVR with nighttime systolic blood pressure (p = 0.002) and age (p = 0.019) taking into consideration gender, smoking, eGFR, ADMA and T2DM. Conclusions: In patients with a very recent diagnosis of Type 2 Diabetes Mellitus, the retinal vessels diameters do not differ compared with individuals of similar age and blood pressure. However, the AVR index correlates with age and nighttime BP, highlighting the important contribution of the latter in early target organ damage in this population.

SUBCLINICAL MAGNETIC RESONANCE IMAGING MARKERS OF CEREBRAL SMALL VESSEL DISEASE IN RELATION TO AMBULATORY BLOOD PRESSURE MEASUREMENTS

Objective: 24-h and nighttime blood pressure (BP) levels are the strongest BP measurements associated with cardiovascular risk. However, it remains undocumented which of the ambulatory BP measurements have the strongest association and predictive information in relation to the presence of cerebral small vessel diseases (CSVD). Design and method: A subset of Maracaibo Aging Study with 429 participants [aged 40 years or older (women, 73.7%; mean age, 59.3y)] underwent baseline brain magnetic resonance imaging to visualize CSVD, which included log-transformed white matter hyperintensities (log-WMH), the presence (yes/no) of silent brain infarcts (SBI), cerebral microbleeds (CMB), or enlarged perivascular spaces (EPVS). Linear and logistic regression models were applied to examine the association between CSVD and each + 10 mmHg increment in the office and ambulatory systolic BP. Improvement in the fit of nested logistic models was assessed by the log-likelihood ratio and the generalized R2 statistic. Results: Office and ambulatory systolic BP measurements were related to log-WMH (beta correlation coefficients above 0.08; P < 0.001). SBI and CMB were only associated with ambulatory systolic BP measurements (odds ratios [OR] ranged from 1.31 [95% confidence interval, 1.10 1.55] to 1.46 [1.17–1.84], P < 0.003). Accounted for daytime systolic BP, both the 24-h (beta correlation, 0.170) and nighttime (beta, 0.038) systolic BP measurements remained related to log-WMH. When accounted for 24-h or daytime systolic BP levels, the nighttime systolic BP retained the significant association with SBI (ORs, 1.05–1.06; 95% CIs, > = 1.01to< = 1.13), whereas the 24-h and daytime systolic BP levels were not associated with SBI after adjustments for nighttime systolic BP (ORs, < = 0.88; 95% CI, > = 0.77to< = 1.14). On top of covariables and office systolic BP, ambulatory systolic BP measurements significantly improved model performance (R2<3.82%). Compared to 24-h and daytime SBP, nighttime systolic BP had the strongest improvement in the model performance; for WMH (1.46% vs. 1.05%) and SBI (3.06% vs. below 2.05%). Conclusions: 24-h and nighttime systolic BP were the more robust BP measurements associated with CSVD, but for log-WMH and SBI, the nighttime systolic BP level had the strongest association. Controlling ambulatory BP levels might provide additional improvement in the prevention of CSVD

PREVALENCE AND PREDICTORS OF NOCTURNAL BLOOD PRESSURE DIPPING IN CHRONIC KIDNEY DISEASE

Objective: Management of blood pressure (BP) in chronic kidney disease (CKD) is critical for preventing cardio-renal complications. Information on nocturnal BP decrease patterns (dipping) in CKD is still scarce. We aimed at describing nocturnal BP dipping patterns and its predictors in patients with CKD. Design and method: We analysed data from patients with CKD stages 1 to 5 referred for kidney function testing from September 2006 to January 2022, including 24-hour urine collection, gold-standard measurement of glomerular filtration rate (GFR) using clearance of a radioisotopic tracer, as well as ambulatory BP measurement (ABPM) in a single tertiary hospital in Paris, France. A total of 1177 ABPM were available in 642 participants. The magnitude of dipping was calculated as the difference between day- and night-time systolic BP (SBP), in percentage of daytime SBP. Factors associated with a less than 10% dipping were analysed with adjusted logistic regression models including a random intercept to deal with clustering of measurements within patients. Results: Participants (mean age 56 ± 15 years; 35% female, mean GFR 49 ± 21 mL/min per 1.73 m2) consisted of 8% extreme-dippers (> = 20%), 37% dippers (10% to < 20%), 40% non-dippers (0% to < 10%), and 15% reverse-dippers (<0%). The prevalence of non- or reverse- dipping increased with CKD severity, from 36% in CKD stage 1 to 65% in CKD stages 4–5 (Figure). Non or reverse dipping was independently associated with measured GFR (odds ratio [OR, 95% confidence interval] per 10 ml/min/1.73m2 decrease = 1.16 [1.06 – 1.26], p = 0.001), daytime ambulatory SBP (OR per 10 mmHg decrease = 1.17 [1.06–1.28], p = 0.001), African origin (OR = 1.56 [1.04 – 2.34], p = 0.03) and 24 h Na/K (OR per 1-unit increase = 1.20 [1.06 – 1.37], p = 0.006). Conclusions: The prevalence of nocturnal non-or reverse dipping BP profiles increases substantially across the spectrum of CKD. Measured GFR, African origin, ambulatory daytime SBP and 24-hour urinary sodium to potassium ratio are independent predictors of abnormal nocturnal BP decrease and thus may help in cardiovascular risk stratification in this population. More research is needed on whether nocturnal dipping may be a treatment target to reduce cardiorenal complications.

BLOOD PRESSURE IN ATRIAL FIBRILLATION AND IN SINUS RHYTHM DURING 24 HOUR AMBULATORY BLOOD PRESSURE MONITORING: DATA FROM THE TEMPLAR PROJECT

Objective: Hypertension is the most common risk factor for atrial fibrillation (AF), and accounts for a worse prognosis. Blood pressure (BP) control is accordingly essential in AF. However, the interpretation of BP levels is difficult in AF, since differences may be dependent on rhythm, particularly when using automated oscillometric devices. We used data from the TEMPLAR project to compare oscillometric ambulatory BP monitoring (ABPM) intra-individually in AF and sinus rhythm (SR). Design and method: Among the 4398 individuals in TEMPLAR > 65 years investigated with ABPM and Afib Microlife detector (rhythm indicated with each BP measurement), those with > 30% of readings indicating AF were selected (as previously recommended), and episodes > 30 mins for AF and SR were chosen. Systolic and diastolic BP, mean arterial pressure (MAP), pulse pressure (PP), averaged real variability (ARV), and its coefficient of variation (CV) were assessed for AF and SR, separated for 24 h, daytime, night-time, and for heart rate (HR) < = 90 and > = 90 bpm. Results: We included 430 individuals (mean age 78 ± 7 years, 57% females, 77% with hypertension and 72% on treatment, 4% with previous AF). Mean BP of all measurements included were 124.2/69.0, 126.3/71.1, and 119.5/64.0 mmHg, for 24 h, daytime, and night-time, respectively. There were no differences in MAP for AF vs SR (p = 0.47). Systolic BP tended to be lower in AF (24 h 123.6 ± 13.9 vs 124.7 ± 16.1 mmHg in SR, p = 0.05), and night-time diastolic BP was higher in AF (64.6 ± 10.9 vs 63.3 ± 10.4 mmHg in SR, p = 0.01). PP was lower in AF (24 h 54.6 ± 10.9 vs 55.7 ± 12.8 mmHg in SR, p = 0.002). Diastolic, but not systolic BP variability (ARV and CV) was higher in AF (24 h, p < 0.001). Results were similar with HR < = 90 and > = 90 bpm. Conclusions: Using an oscillometric ABPM device, our results suggest that MAP is similar and reliable in both AF and SR. Lower systolic and higher diastolic BP in AF affects PP, which together with a high variability might impact arterial structure. However, differences in absolute numbers are small, and do not imply different BP strategies and target values in AF.

Insights From Matched Office and Ambulatory Blood Pressure in Youth: Clinical Relevance.

Information on the relationship between ambulatory blood pressure (ABP) and concurrently office blood pressure (BP) values in youth still suffers from limitations. We provide information on the differences between office BP and ABP, the factors related, and the clinical implications. Three thousand six hundred ninety matched measurements of office BP and ABP on the same day, from 2390 children, aged 5 to 15 years, of both sexes were eligible. Office BP was measured using an oscillometric device (Omron 705 IT) and 24-hour ABP using oscillometric SpaceLabs 90207. Average of office, 24-hour, daytime, nighttime, systolic, and diastolic BP and heart rate was calculated. BP categories according to the European guidelines and phenotype of mismatch office BP versus ABP were defined. Both daytime systolic and diastolic BP were higher than office BP with a progressive reduction of the differences from 5 to 15 years. The office minus daytime BP differences were the largest in normotensive subjects, less at high-normal, and reversed in hypertensive ones, independently of age and weight status. White coat and masked hypertension covered no more than 13.6% at all ages. In youth, it is inaccurate to obtain reference values for ABP by extrapolating from office BP values. The differences between office BP and ABP are minimal in children with office BP values in the range of hypertension, reinforcing the recommendation to use ABP measurement at the time to confirm hypertension.

NIGHT-TIME BLOOD PRESSURE IN DIABETES TYPE-1 ASSESSED BY HOME VS. AMBULATORY MONITORING: A PILOT STUDY

Objective: To compare night-time (asleep) blood pressure (BP) evaluated by home monitoring (HBPM) vs. ambulatory monitoring (ABPM) in adolescents and young adults with diabetes type-1 (DM1) and examine their association with indices of preclinical target organ damage (TOD). Design and method: Individuals aged 12–30 years with DM1 were subjected to 24-hour ABPM (every 20 min, Microlife WatchBP O3) and 7-day HBPM (daytime: duplicate morning and evening measurements; night-time: 3 measurements per night for 3 nights; Microlife WatchBP Home-N), as well as TOD assessment (left ventricular mass index, carotid intima media thickness, urine albumin excretion). Results: Data from 24 individuals were analysed (mean age 19.8 ± 5.3 [SD] years, men 62.5%, BMI 25.6 ± 4.1 kg/m2, 13% with elevated 24-hour ABPM]. The number of valid ABPM readings was 45.7 ± 1.4/22.4 ± 4.8 (awake/asleep, mean ± SD) and HBPM 26.3 ± 2.1/8.3 ± 2.0 respectively (p < 0.001/ < 0.001). Daytime HBPM was lower than ABPM (by 2.7 ± 0.1/1.9 ± 0.7 mmHg, systolic/diastolic, p < 0.05/ < 0.05), but night-time was higher (difference 5.0 ± 0.6/3.2 ± 0 mmHg, p < 0.01/ < 0.05). There was a strong association between HBPM and ABPM (daytime r = 0.85/0.88, night-time r = 0.68/0.49, systolic/diastolic). There was fair agreement (88%; kappa = 0.33) between ABPM and HBPM in diagnosing nocturnal hypertension (age > = 16 years > = 120/70 mmHg; < 16 years > = 95th centile;) and poor agreement in detecting non-dippers (38%, kappa = 0.032). No significant association of night-time ABPM or HBPM and indices of TOD was found, probably due to small sample size and low prevalence of TOD. Conclusions: These preliminary data in young individuals with DM1 show that nocturnal HBPM is feasible and provides values similar to ABPM. Further research is needed to extend these finding and investigate their clinical relevance in DM1.

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.

LONG SLEEP DURATION AND AMBULATORY BLOOD PRESSURE

Objective: Studies show a link between short sleep duration and hypertension. The mechanistic associations between sleep duration and blood pressure (BP) are less clear. We studied the association between sleep duration, blood pressure, metabolic profile as well as obstructive sleep apnoea in participants with suspected or confirmed hypertension undergoing 24 h ambulatory blood pressure measurement (ABPM). Design and method: We included 177 participants (mean age 57 ± 11 years, 67 women) referred for ABPM, with available exact time-points for bedtimes during the recording. Daytime and night-time BP values were calculated accordingly. Biochemistry included triglycerides (TG), high- and low-density lipoproteins (HDL, LDL) and total cholesterol. The HDL/TG ratio was calculated as a marker of glucose intolerance. Sleep apnoea was quantified by simultaneous ambulatory polygraphy. Results: Participants were stratified into those with short (n = 16) /normal (n = 139) /long (n = 22) sleep (< = 6 h, > 6 < = 9 h and > 9 h). There were no differences in age, body mass index (BMI) or apnoea hypopnea index (AHI) between groups. Mean office BP was 146 ± 19/89 ± 11 mmHg and mean 24 h ABPM 133 ± 14/80 ± 8 mmHg. By standard ABPM definitions 81, 86, and 77% in the short/normal/long sleep group were hypertensive, and 56, 56 and 73% were on antihypertensive medication. The long sleep group had lower 24 h diastolic BP than the short and normal sleep groups (p < 0.05 by ANOVA). TG levels and TG/HDL ratio were higher in the long sleep group than in the short sleep group (both p < 0.05 by ANOVA; not adjusted for statin treatment). No differences were found in HDL, LDL, or total cholesterol between groups. In a multiple linear regression model, longer sleep duration, older age, and female sex were all independently associated with lower 24 h ABPM diastolic BP (all p < 0.01; full model R2 = 0.25, p < 0.001) while BMI, AHI, TG, and the TG/HDL ratio were not related. Conclusions: Longer sleep duration was independently associated with lower ABPM 24 h diastolic BP together with older age and female sex. The observation with increased TG and TG/HDL ratio in the long sleep group warrants further study.

PROGNOSTIC SIGNIFICANCE OF BLOOD PRESSURE PARAMETERS FOR PREDICTING CARDIOVASCULAR DEATH

Objective: The nycterohemeral rhythm of blood pressure (BP) and heart rate has been associated with cardiovascular outcomes. However, long-term prognostic significance of BP at different levels of heart rates has rarely been studied. We therefore conducted the present analysis to investigate the prognostic values for cardiovascular outcome by the ambulatory BP parameters during different time windows Design and method: We enrolled 5 large cohorts from whole world, including CARDIA, IDACO, JHS, SPRINT to find out independent prognostic factors for cardiovascular disease mortality, feature engineering and feature transformation were used. Several statistical and machine learning methods including the stepwise procedure, lasso penalty, and random survival forest with bootstrap technique were used to screen important candidates of risk factors. Models building are based on systolic BP replacement into the established Framingham risk score. Directly one to one replacement and indirectly two stage replacement methods are considered with variable diversity. C-statistics, NRI are used for model performance evaluation. Results: In model building procedure, nighttime BP combined with pulse pressure, morning-evening difference of SBP and weighted SBP consistently had a higher C-statistics than had office systolic BP. In validation datasets, equations incorporating mean BP and pulse pressure had best performance in C-index (0.754). In contrast, the C-index (higher is better), of the usual Framingham risk score with office systolic BP are 0.744. Furthermore, the best model had acceptable predicted accuracy based on model calibration statistics (p > 0.05). Conclusions: Our study demonstrated that mean BP at night combined with pulse pressure, morning-evening difference of SBP and weighted SBP, throughout 24 hours had the largest predictive power of 20-year cardiovascular death in population with ABPM recordings. The transportability of the proposed cardiovascular risk function should be evaluated in future studies.

NIGHT-TIME BLOOD PRESSURE ASSESSED BY HOME VS. AMBULATORY MONITORING IN ADULTS WITH TYPE 2 DIABETES: ASSOCIATION WITH PRECLINICAL TARGET ORGAN DAMAGE

Objective: To evaluate the relationship of night-time blood pressure (BP) assessed by home (HBP) or ambulatory BP (ABP) monitoring with preclinical target organ damage in adults with type 2 diabetes (DM2). Design and method: Hypertensive adults with DM2 or pre-diabetes on stable treatment were subjected to (i) 24 h ABP monitoring (20 min intervals, Microlife WatchBP O3), (ii) HBP monitoring (7 days with duplicate morning/evening measurements and 3 nights with 3 measurements/night, Microlife WatchBP Home-N), and measurement of (iii) echocardiographic left ventricular mass index (LVMI), (iv) carotid intima-media thickness (cIMT), (v) aortic pulse wave velocity (PWV) and ankle-brachial index (ABI), (Microlife PWV/ABI), (vi) urine albumin-creatinine ratio (ACR) in 2 different morning samples. Results: Seventy individuals were analyzed (mean age 65.2 ± 9.7 years, 47 males, body mass index 31.6 ± 4.8 kg/m2, 59 with DM2 and 11 with pre-DM). Daytime HBP was slightly higher than daytime ABP (mean difference 2.4 ± 9.3/0.5 ± 4.9 mmHg, systolic/diastolic, p < 0.05/NS). Similarly, night-time HBP was slightly higher than night-time ABP (2.1 ± 6.5/0.8 ± 5.0 mmHg, p < 0.05/NS). There was strong correlation between ABP and HBP (daytime r = 0.77/0.77 and night-time 0.88/0.80, systolic/diastolic) (all p < 0.05). Night-time ambulatory/home pulse pressure presented the following correlation coefficients with indices of target organ damage: LVMI r = 0.23/0.15; cIMT 0.28/0.28; ABI -0.21/-0.23; PWV 0.04/0.05; ACR 0.57/0.50 (p = NS for HBP-ABP comparisons). The agreement between night-time HBP and ABP in identifying individuals with nocturnal hypertension was 81% (kappa statistic = 0.63) and in detection of non-dippers 73% (kappa = 0.44). Conclusions: Night-time HBP monitoring in hypertensive adults with DM2 is feasible, strongly associated with night-time ABP and gives similar correlations with preclinical target organ damage. These methods also present substantial agreement in identifying individuals with nocturnal hypertension.

SIMPLE PREDICTIVE SCORE FOR NOCTURNAL HYPERTENSION AND MASKED NOCTURNAL HYPERTENSION USING HOME BLOOD PRESSURE MONITORING IN CLINICAL PRACTICE

Objective: The decision whether to measure nighttime blood pressure (BP) is challenging because these values cannot be easily evaluated due to problems with measurement devices and related stress. Using the nationwide, practice-based Japan Morning Surge-Home BP Nocturnal BP study data, we developed a simple predictive score that physicians can use to diagnose nocturnal hypertension. Design and method: We divided 2,765 outpatients (mean age 63 years; hypertensives 92%) with cardiovascular risks who underwent morning, evening, and nighttime home BP (HBP) measurements (2:00, 3:00, and 4:00 a.m.) into a calibration group (n = 2,212) and validation group (n = 553). We used logistic-regression models in the calibration group to identify the predictive score for nocturnal hypertension (nighttime HBP > = 120/70 mmHg) and then evaluated the score's predictive ability in the validation group. Results: In the logistic-regression model, male sex, increased body mass index (BMI) (> = 25 kg/m2), diabetes, elevated urine-albumin creatinine ratio (UACR) (> = 30 mg/g Cr), elevated office BP (> = 140/90 mmHg), and elevated morning and evening HBP (> = 135/85 mmHg) had positive relationships with nocturnal hypertension. The predictive scores for nocturnal hypertension were 1-point (male, BMI, diabetes, and UACR); 2-points (office BP > = 140/90 mmHg); 3-points (evening HBP > = 135/85 mmHg); 4-points (morning HBP > = 135/85 mmHg); total 13 points. Over 80% of the nocturnal hypertension cases in the validation group showed > = 10-points (AUC = 0.705, 95%CI: 0.661–0.748). We also developed a score for masked nocturnal hypertension, i.e., nocturnal hypertension despite controlled daytime HBP. Conclusions: We developed a simple predictive score for nocturnal hypertension that can be used in clinical settings and for diagnoses.

IMPACT OF LONG-TERM USE OF CPAP TREATMENT ON BLOOD PRESSURE AMONG REFRACTORY HYPERTENSIVE PATIENTS WITH OBSTRUCTIVE SLEEP APNEA

Objective: To assess blood pressure response to long-term continuous positive airway pressure (CPAP) treatment among patients with refractory hypertension (RfHTN) with moderate and severe obstructive sleep apnea (OSA). Design and method: An observational prospective study was performed in 26 patients (35.7% male, average age 59.3 ± 7.9 years) with diagnostic of RfHTN and moderate and severe OSA who were divided in 2 groups to use CPAP (CPAP group, n = 13) or not (control group, n = 15). All of them were submitted to clinical follow-up and their anti-hypertensive medication was adjusted according to the assistant physician. 24-hour ABPM was performed both at the beginning and at the end of the study. Primary outcomes were changes in office and ambulatory blood pressure (BP) and BP control. The comparison between groups of BP changes were calculated by a general linear model with group allocation as a fixed factor and adjusted by its respective BP basal values in addition to gender and age. Results: The median follow-up time was 68 months (IQR: 49–81 months). CPAP and control groups were similar in their baseline demographic, anthropometric, laboratory characteristics, and office and ambulatory BP. They had mean systolic and diastolic 24-hour BP of 142 (15) and 83 (14), respectively. At the end of follow-up, refractory patients using CPAP had a reduction of 8.5 and 5.0 mmHg of office systolic and diastolic BP with an intergroup difference (CPAP and control) of 13.5 (-15.2 – 42.3) mmHg and 10.1 (-7.5 – 5.4) mmHg, respectively. The most important difference between groups was noticed at nighttime with an intergroup difference of 10.0 (-8.6 – 28.7) mmHg of systolic BP and 6.7 (-3.9 – 17.3) mmHg of nighttime diastolic BP. Out of 28 initial refractory patients, 12 are not refractory anymore, being 3 (20%) in control group and 9 (69.2%) in CPAP group with a significant difference between the groups (p = 0.02) Conclusions: Long-term use of CPAP among refractory hypertensive patients with moderate/severe OSA seems to be effective to reduce and control blood pressure measured both in the office BP and 24-hour ABPM, especially lowering nighttime blood pressure.

ASSOCIATION BETWEEN NON-DIPPER OR NIGHT-TIME BLOOD PRESSURE PATTERN AND ALCOHOL DRINKING OR QUALITY OF SLEEP IN KOREAN REGISTRY OF AMBULATORY BLOOD PRESSURE MONITORING STUDY

Objective: Non-dipper or reverse dipper is known to be associated with adverse cardiovascular prognosis in general population and clinical cohort. There are few large sized to explore the factor related to non-dipper or nighttime blood pressure pattern in terms of sleep quality and lifestyle factors. Design and method: With the database of Korean multicenter nationwide prospective Registry of Ambulatory Blood Pressure monitoring (KORABP) study, 3745 patients referred for blood pressure evaluation was nalysed for clinical profiles including current smoking and alcohol drinking habits, sleep quality in 4 Likert scale as hardly sleep, poor sleep, not so bad, and very good with 1 to 4 points, and medical history. Results: Age was 55.5+/-14.3 years and female was 45%. BMI was 24.7+/-3.4 kg/m2. 33.6% of the study population. Smoking and drinking habits 14.6% and 37.2%, respectively. Prevalence of diabetes mellitus, hypercholesterolemia, and cardiovascular diseases were 19.0%, 27.9% and 22.1%, respectively. Normotensive, untreated hypertension, and treated hypertension were 29.1%, 37.2% and 33.6%, respectively. Sleep qualities in hardly sleep, poor sleep, not so bad, and very good were 14.7%, 32.6%, 32.1% and 20.6%, respectively. In multivariable regression analyses for non-dipper or reverse dipper, age > 56 years, cardiovascular disease history, hypertension by ABPM, and poor sleep are positively associated factors whereas drinking and hypertension by clinic BP were negatively associated factors. Antihypertensive medication has no association. Sleep quality was negatively and positively associated with extreme dipper and reverse dipper, respectively. Conclusions: Age, cardiovascular diseases, and hypertension by ABPM were associated with non-dipper. Drinking was associated with dipper. Good and poor sleep qualities were significant factors for extreme dipper and reverse dipper or non-dipper, respectively.

Wearable cuffless blood pressure monitoring devices: a systematic review and meta-analysis.

High blood pressure (BP) is the commonest modifiable cardiovascular risk factor, yet its monitoring remains problematic. Wearable cuffless BP devices offer potential solutions; however, little is known about their validity and utility. We aimed to systematically review the validity, features and clinical use of wearable cuffless BP devices. We searched MEDLINE, Embase, IEEE Xplore and the Cochrane Database till December 2019 for studies that reported validating cuffless BP devices. We extracted information about study characteristics, device features, validation processes, and clinical applications. Devices were classified according to their functions and features. We defined devices with a mean systolic BP (SBP) and diastolic BP (DBP) biases of <5 mmHg as valid as a consensus. Our definition of validity did not include assessment of device measurement precision, which is assessed by standard deviation of the mean difference-a critical component of ISO protocol validation criteria. Study quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies version 2 tool. A random-effects model meta-analysis was performed to summarise the mean biases for SBP and DBP across studies. Of the 430 studies identified, 16 studies (15 devices, 974 participants) were selected. The majority of devices (81.3%) used photoplethysmography to estimate BP against a reference device; other technologies included tonometry, auscultation and electrocardiogram. In addition to BP and heart rate, some devices also measured night-time BP (n = 5), sleep monitoring (n = 3), oxygen saturation (n = 3), temperature (n = 2) and electrocardiogram (n = 3). Eight devices showed mean biases of <5 mmHg for SBP and DBP compared with a reference device and three devices were commercially available. The meta-analysis showed no statistically significant differences between the wearable and reference devices for SBP (pooled mean difference = 3.42 mmHg, 95% CI: -2.17, 9.01, I2 95.4%) and DBP (pooled mean = 1.16 mmHg, 95% CI: -1.26, 3.58, I2 87.1%). Several cuffless BP devices are currently available using different technologies, offering the potential for continuous BP monitoring. The variation in standards and validation protocols limited the comparability of findings across studies and the identification of the most accurate device. Challenges such as validation using standard protocols and in real-life settings must be overcome before they can be recommended for uptake into clinical practice.

Impact of COVID‐19 on Ambulatory Daytime and Nighttime Blood Pressure in Young Otherwise Healthy Adults

BackgroundCOVID‐19 has been shown to cause impairments in vascular function and elevations in resting sympathetic nerve activity in young otherwise healthy adults. Notably, our laboratory recently reported that persistence of COVID‐19 symptoms beyond the acute phase of the illness (i.e., beyond 4 weeks) was accompanied by macro‐ and micro‐ vascular dysfunction as measured by flow mediated dilation and reactive hyperemia, respectively. Interestingly, despite consistent reports of vascular alterations, no studies have reported changes in resting blood pressure (BP) following COVID‐19. One caveat is that BP has only been measured in the laboratory setting. Indeed, to date, no studies have assessed the effect of COVID‐19 on ambulatory BP, which allows for a complete assessment of daytime and nighttime BP without the potential for well known “white coat” effects on BP. Thus, we aimed to investigate the effect of COVID‐19 on 24‐hr ambulatory BP in young adults diagnosed with COVID‐19 within the preceding 6 months. We hypothesized that ambulatory BP would be greater in individuals who had COVID‐19 compared to controls who never had COVID‐19, and that those with symptoms would have higher BP compared to those who were asymptomatic at the time of testing.MethodsWe studied 21 young healthy adults who had a positive laboratory diagnosis of COVID‐19 (COVID: 23 ± 1 years [Mean ± SE]; 12 ± 1 [range: 4 to 22] weeks since diagnosis; 13 females) and 10 controls (23 ± 1 years, 6 females) who never had COVID‐19. Eleven individuals who had COVID‐19 were asymptomatic at the time of testing while 10 were symptomatic. Ambulatory BP was measured using the Oscar 2 oscillometric monitor (Sun Tech Medical). Participants were instructed to perform normal daily activities but not to perform any exercise during the 24‐hr period. Measurements were obtained every 20 min during daytime and every 30 min during nighttime. Average daytime, nighttime and 24‐hr systolic BP (SBP), diastolic BP (DBP), and mean arterial pressure (MAP) were calculated.ResultsDaytime, nighttime, and 24‐hr BPs were not different between control and COVID subjects (P > 0.05 for all comparisons). Similarly, there were no differences in any of the BP assessments between control, asymptomatic or symptomatic COVID subjects (e.g., daytime SBP: control 122 ± 4; asymptomatic 119 ± 4; symptomatic 125 ± 2 mmHg, P = 0.451). Interestingly, in the COVID group, daytime, nighttime, and 24‐hr SBP, DBP, and MAP were inversely correlated with time since diagnosis (P < 0.05 for all with medium to large effect size). Multiple linear regression showed that after accounting for age, BMI, and physical activity (reported average exercise minutes/week), time since diagnosis was a significant predictor of daytime and 24‐hr SBP, DBP, and MAP (e.g., daytime SBP: P = 0.028, β coefficient = ‐0.697). For nighttime BP, time since diagnosis was a significant predictor only for SBP.ConclusionThese preliminary data suggest that the effect of COVID‐19 on ambulatory BP in young adults may be dependent on the time since diagnosis with higher daytime and nighttime BP present closer to the onset of the infection, which appeared to be independent of symptomology. Longitudinal follow up studies are warranted.

Nighttime Blood Pressure Dipping is Attenuated in Young and Apparently Healthy Black Adults Compared to White Adults

In America, Black adults are 30% more likely to die from cardiovascular disease (CVD) compared to White adults, and more than half of this racial disparity in CVD‐related mortality may be attributed to the substantially greater prevalence of high blood pressure (BP) in Black adults. Furthermore, compared to White adults with hypertension, Black adults with hypertension are less likely to exhibit a nocturnal reduction in BP (i.e., “dipping”). Importantly, non‐dipping BP is associated with target organ damage and increased CVD risk. However, it is unclear whether young and apparently healthy Black adults exhibit reduced BP dipping compared to their White peers.PURPOSETherefore, the purpose of this preliminary investigation was to determine whether there are racial differences in BP dipping using ambulatory BP monitoring (ABPM), including 24‐hour‐, daytime‐, and nighttime‐BP, in young and apparently healthy Black and White adults.METHODSWe obtained clinical BP and 24‐hour ABPM readings in 10 self‐identified White adults (5M/5F; age: 21.6±4.4 yrs; BMI: 23.8±2.9 kg/m2; Mean±SD) and 7 self‐identified Black adults (3M/4F; age: 21.7±3.5 yrs; BMI: 25.1±2.8 kg/m2). The ABPM monitors were programmed to record BP every 20 and 30 minutes during each participants daytime‐ and nighttime‐period, respectively. True daytime‐ and nighttime‐BP periods were adjusted during analysis based upon participant activity logs. We defined “non‐dipping” as a failure to achieve a dipping ratio of &lt;0.90 (night‐to‐day BP ratio). BP data were compared using independent t‐tests and the Fisher’s exact test was used to compare dipping frequency between races (α=0.05).RESULTSClinically measured BP (systolic/diastolic) was not different (P&gt;0.05) between White (117±9/67±6 mmHg) and Black (124±12/70±9 mmHg) adults. There was also no difference (P&gt;0.05) in 24‐hour‐BP between White (117±11/66±7 mmHg) and Black (114±14/63±7 mmHg) adults. Likewise, daytime‐BP was not different (P&gt;0.05) between White (122±12/71±8 mmHg) and Black (116±14/66±8 mmHg) participants, nor was there a difference in nighttime‐BP (P&gt;0.05) between White (102±9/51±4 mmHg) and Black (105±13/54±7 mmHg) adults. However, systolic BP dipping was attenuated (P=0.04) in Black (0.90±0.05) compared to White (0.84±0.07) adults. Non‐dipping of systolic BP was observed in 5 of 7 Black participants and 2 of 10 White participants (P=0.06). Diastolic BP dipping in Black adults was 0.79±0.06 and White adults was 0.73±0.09 (P=0.05). Non‐dipping of diastolic BP was observed in 1 of 7 Black participants and 1 of 10 White participants (P=1.00).CONCLUSIONSThese preliminary data suggest that despite similar clinical and 24‐hour ambulatory BP compared to White adults, young and apparently healthy Black adults exhibit impaired BP dipping, which may contribute to increased likelihood of CVD.

Is there a relationship between heart rate recovery and blood pressure in white coat hypertension?

Aim Increasing evidence suggests that autonomic dysfunction may be involved in the etiology of white coat hypertension (WCH). The aim of this study was to evaluate cardiac autonomic function by using heart rate recovery (HRR) indices in patients with WCH classified according to their circadian rhythm type of blood pressure (BP).Material and methods This cross-sectional study included 120 participants over the age of 18 yrs, including 50 patients diagnosed with WCH and 70 healthy controls with normal in- and out-of-office BP and without any known disease. Circadian rhythm types, i.e., dippers and non-dippers, were identified using ambulatory BP monitoring. The HRR indices were calculated by subtracting the 1st-minute (HRR1), 2nd-minute (HRR2), and 3rd-minute (HRR3) heart rates from the maximal heart rate recorded during stress testing.Results The lesser decline in nighttime BP (6.4±2.14 and 13.3±2.2 mmHg, respectively; p&lt;0.001) and the smaller mean HRR1 (25.5±3.0 and 30.3±3.1 beats / min, respectively; p&lt;0.001) were evident in WCH non-dippers compared to WCH dippers. Linear regression analysis showed that HRR1 (β±SE=0.43±0.11; p&lt;0.001) and diastolic BP at maximum exercise (β±SE=0.14±0.07; p=0.040) are independent risk factors for the blunted decline in nighttime BP.Conclusion Delayed recovery of heart rate after an exercise stress test is associated with non-dipper type of circadian rhythm of BP. This was more pronounced in WCH patients, and these patients are at risk of autonomic dysfunction.

Ambulatory diastolic blood pressure: a marker of comorbidity in elderly fit hypertensive individuals?

BACKGROUNDMasked diastolic hypotension is a new blood pressure (BP) pattern detected by ambulatory blood pressure monitoring (ABPM) in elderly hypertensives. The aim of this study was to relate ABPM and comorbidity in a cohort of fit elderly subjects attending an outpatient hypertension clinic.METHODSComorbidity was assessed by Charlson comorbidity index (CCI) and CHA2DS2VASc score. All subjects evaluated with ABPM were aged ≥ 65 years. CCI and CHA2DS2VASc score were calculated. Diastolic hypotension was defined as mean ambulatory diastolic BP < 65 mmHg and logistic regression analysis was carried out in order to detect and independent relationship between comorbidity burden and night-time diastolic BP < 65 mmHg. RESULTSWe studied 174 hypertensive elderly patients aged 72.1 ± 5.2 years, men were 93 (53.4%). Mean CCI was 0.91 ± 1.14 and mean CHA2DS2VASc score of 2.68 ± 1.22. Subjects with night-time mean diastolic values < 65 mmHg were higher in females [54.7% vs. 45.3%, P = 0.048; odds ratio (OR) = 1.914, 95% CI: 1.047−3.500]. Logistic regression analysis showed that only CHA2DS2VASc score was independently associated with night-time mean diastolic values < 65 mmHg (OR = 1.518, 95% CI: 1.161−1.985; P = 0.002), but CCI was not. CONCLUSIONSABPM and comorbidity evaluation appear associated in elderly fit subjects with masked hypotension. Comorbid women appear to have higher risk for low ambulatory BP.

Aerobic exercise training improves nocturnal blood pressure dipping in medicated hypertensive individuals.

The absence of nocturnal blood pressure (BP) reduction at night in hypertensive individuals is associated with an increased cardiovascular risk. The main purpose of the present study was to investigate the effects of an aerobic training intervention on nocturnal BP dipping in medicated hypertensive individuals. At baseline, hypertensive individuals under pharmacological treatment underwent 24-h ambulatory BP monitoring and a morning urine sample to analyze albumin creatinine ratio (UACR). Then, participants were divided into nocturnal dippers ( N = 15; 59 ± 6 years) and nondippers ( N = 20; 58 ± 5 years) according to a day-to-night BP reduction of >10% or <10%, respectively. Next, participants underwent a 3-weekly, 4-month aerobic interval training intervention. Follow-up measurements revealed a reduction in daytime diastolic BP in dippers and nondippers ( Ptime < 0.001), whereas nighttime systolic BP was reduced only in nondippers ( P = 0.004). Regarding dipping pattern, nocturnal systolic BP dipping increased after training in nondippers (5 ± 3 to 9 ± 7%; P = 0.018), whereas in dippers, there was a decrease in nocturnal dipping after training (14 ± 4 to 10 ± 7%, P = 0.016). Nocturnal diastolic BP dipping did not change in nondippers (8 ± 5 to 10 ± 7%; P = 0.273) but decreased in dippers (17 ± 6 to 12 ± 8%; P = 0.004). In addition, UACR was significantly reduced in both groups after training ( Ptime = 0.020). Aerobic exercise training is associated with nocturnal BP dipping as nighttime BP was lower than before the program in medicated hypertensive individuals with an initial nondipping phenotype. The lack of improvement in individuals with a dipping phenotype warrants further investigation to discern whether dipping phenotypes influence BP responses to exercise training.

Endothelial Cullin3 Mutation Impairs Nitric Oxide-Mediated Vasodilation and Promotes Salt-Induced Hypertension.

Human hypertension caused by in-frame deletion of CULLIN3 exon-9 (Cul3∆9) is driven by renal and vascular mechanisms. We bred conditionally activatable Cul3∆9 transgenic mice with tamoxifen-inducible Tie2-CREERT2 mice to test the importance of endothelial Cul3. The resultant mice (E-Cul3∆9) trended towards elevated nighttime blood pressure (BP) correlated with increased nighttime activity, but displayed no difference in daytime BP or activity. Male and female E-Cul3∆9 mice together exhibited a decline in endothelial-dependent relaxation in carotid artery. Male but not female E-Cul3∆9 mice displayed severe endothelial dysfunction in cerebral basilar artery. There was no impairment in mesenteric artery and no difference in smooth muscle function, suggesting the effects of Cul3∆9 are arterial bed-specific and sex-dependent. Expression of Cul3∆9 in primary mouse aortic endothelial cells decreased endogenous Cul3 protein, phosphorylated (S1177) endothelial nitric oxide synthase (eNOS) and nitric oxide (NO) production. Protein phosphatase (PP) 2A, a known Cul3 substrate, dephosphorylates eNOS. Cul3∆9-induced impairment of eNOS activity was rescued by a selective PP2A inhibitor okadaic acid, but not by a PP1 inhibitor tautomycetin. Because NO deficiency contributes to salt-induced hypertension, we tested the salt-sensitivity of E-Cul3∆9 mice. While both male and female E-Cul3∆9 mice developed salt-induced hypertension and renal injury, the pressor effect of salt was greater in female mutants. The increased salt-sensitivity in female E-Cul3∆9 mice was associated with decreased renovascular relaxation and impaired natriuresis in response to a sodium load. Thus, CUL3 mutations in the endothelium may contribute to human hypertension in part through decreased endothelial NO bioavailability, renovascular dysfunction, and increased salt-sensitivity of BP.