Nighttime Heart Rate Research Articles

Association of depressive symptoms with health care service utilization in adults with chronic disease: A nationally representative sample

Increased cardiovascular risk associated with sleep-onset insomnia has been reported, but the patterns of heart rate (HR) transitions during sleep onset in individuals with sleep-onset insomnia remain uncertain. This study explored the HR dynamics during objective and subjective sleep onset transitions among sleep-onset insomnia.Seventeen good sleepers and 17 individuals with sleep-onset insomnia had their night-time HR measured. HR and heart rate variability (HRV) were analyzed within 8-min periods of pre- and post-transition of stage N1, stage N2 and subjective sleep onset.A significantly higher low-frequency percentage of HRV was observed in pre-N1 period among insomnia group, compared with good sleepers. Decline in HR begins in 160 s prior to N1 onset among good sleepers, whereas the HRs of insomnia group were reduced only after N1 onset in comparison to their HRs at the time of N1 onset. The good sleepers and insomnia group both had their HRs dropped to a level comparable to their HRs at respective stage N2 onset at 220 s and 80 s prior to N2 onset. No differences in HR was found during subjective sleep onset transition in both groups.During the wake-to-sleep transition, a low and stable HR was observed before cortical alternations in good sleepers; however, a consistently high HR until N1 onset was shown among sleep-onset insomnia. This finding suggests a state-dependent and failure to de-arouse from the high arousal level of wakefulness into light sleep is associated with sleep initiation difficulty.

Continuous Positive Airway Pressure Reduces Night-Time Blood Pressure and Heart Rate in Patients With Obstructive Sleep Apnea and Resistant Hypertension: The RHOOSAS Randomized Controlled Trial.

Most patients with resistant hypertension (RH) have obstructive sleep apnea (OSA). We aimed to determine the impact of OSA and continuous positive airway pressure (CPAP) treatment on the leptin profile and blood pressure (BP) in patients with RH. After an initial case-control study (RH with and without OSA), we performed a randomized, single blind study in OSA + RH patients receiving either sham CPAP (3 months) followed by active CPAP (6 months) or 6 months of active CPAP. The primary outcome was the comparison of leptin levels between groups of RH patients with or without OSA. Secondary outcomes were the comparison of metabolic parameters, biomarkers of sympathetic activity, and BP indices between the two groups of RH patients with or without OSA. The same outcomes were then evaluated and compared before and after sham and effective CPAP intervention. Sixty-two patients (60 ± 10 years; 77% men) with RH (24-h daytime systolic BP (SBP)/diastolic BP: 145 ± 13/85 ± 10 mmHg, 3.7 antihypertensive drugs) were included. The 37 RH patients exhibiting OSA (60%) were predominantly men (87 vs 64% for non-OSA patients), with a greater prevalence of metabolic syndrome and higher creatininemia. Their leptin concentrations were significantly lower than in non-OSA patients [9 (6; 15) vs 17 (6; 29) ng/mL] but increased after 6 months of CPAP. Three months of effective CPAP significantly decreased night-time SBP by 6.4 mmHg and heart rate (HR) by 6.0 bpm, compared to sham CPAP. The association between OSA and RH corresponds to a specific, predominately male phenotype with a higher burden of metabolic syndrome and higher creatininemia but there was no significant difference between OSA and non-OSA patients regarding BP indices, and the number of antihypertensive drugs used. Active CPAP could be efficient at decreasing night-time BP and HR, but there was no difference between CPAP and sham CPAP groups for all metabolic and SNS markers (NCT00746902 RHOOSAS).

Persistent tachycardia in clozapine treated patients: A 24-hour ambulatory electrocardiogram study

Tachycardia is associated with cardiovascular mortality. Tachycardia is also a known clozapine adverse effect. However, whether clozapine-associated tachycardia is persistent is not known. Thirty clozapine-treated patients with clinical tachycardia were investigated with 24-hour ambulatory electrocardiography (ECG). Baseline peripheral heart rate (HR) was 106.7±7.8. The ambulatory ECG 24-hour-HR was 98.7±9.7. Baseline HR and 24-hour-HR correlated strongly (r=0.74, p=0.000003). Daytime HR was 106.4±9.9 and nighttime HR 89.2±12.0. Low dose bisoprolol reduced HR significantly. The high 24-hour-HR indicates a persistent tachycardia. Tachycardia should not discourage from clozapine use but the findings indicate a need of guidelines for detection and treatment of clozapine-associated tachycardia.

Low night-time heart rate is longitudinally associated with lower augmentation index and central systolic blood pressure in hypertension.

Several studies have shown that the augmentation index (AIx) is negatively correlated with heart rate (HR). This led some authors to claim that the use of HR-lowering drugs may be detrimental in hypertension. The aim of this study was to assess the longitudinal and cross-sectional relationships of HR with AIx and central blood pressure (BP) in 346 subjects from the HARVEST (mean age 30.7 ± 8.5years). At baseline, HR was measured with 24-h ambulatory recording. Central hemodynamics were evaluated with Specaway DAT system after a median of 8.0years from baseline. In multivariate linear regression analyses, AIx and central systolic BP were used as dependent variables and night-time HR or office HR as predictors adjusting for several risk factors and confounders. In fully adjusted models, baseline night-time HR was a significant positive predictor of AIx (p < 0.001) and central BP (p = 0.014) measured 8years later. Adjusted office HR measured at the time of arterial distensibility assessment was inversely correlated with AIx (p = 0.001) a relationship which was attenuated after physical activity (p = 0.004) and left ventricular ejection time (p = 0.015) were taken into account. In addition, office HR was inversely correlated with central BP (p = 0.039) a relationship which was no longer significant after physical activity and ejection time were accounted for. These data show that HR measured during sleep is longitudinally associated with AIx and central BP. Thus, low HR in the long term may have beneficial effects on central hemodynamics and the wall properties of the large arteries in hypertension.

Association Between Heart Rate and Subclinical Cerebrovascular Disease in the Elderly.

Although increased heart rate (HR) is a predictor of cardiovascular events and mortality, its possible association with subclinical cerebrovascular disease, which is prevalent in the elderly, has not been evaluated. This study aimed to investigate the association of daytime, nighttime, 24-hour HR, and HR variability with subclinical cerebrovascular disease in an elderly cohort without history of stroke. The study cohort consisted of 680 participants (mean age, 73±7 years; 42% men) in sinus rhythm who underwent 24-hour ambulatory blood pressure and HR monitoring, 2-dimensional echocardiography, and brain magnetic resonance imaging as part of the CABL study (Cardiac Abnormalities and Brain Lesion). Subclinical cerebrovascular disease was defined as silent brain infarcts and white matter hyperintensity volume (WMHV). The relationship of HR measures with the presence of silent brain infarct and upper quartile of log WMHV (log WMHV4) was analyzed. Presence of silent brain infarct was detected in 93 participants (13.7%); mean log WMHV was -0.92±0.93 (median, -1.05; min, -5.88; max, 1.74). Multivariate analysis showed that only nighttime HR (adjusted odds ratio, 1.29 per 10 bpm; 95% confidence interval, 1.03-1.61; P=0.026) was significantly associated with log WMHV4, independent of traditional cardiovascular risk factors, ambulatory systolic blood pressure, and echocardiographic parameters. No similar association was observed for daytime HR and HR variability. There was no significant association between all HR measures and silent brain infarct. In a predominantly elderly cohort, elevated nighttime HR was associated with WMHV, suggesting an independent role of HR in subclinical cerebrovascular disease.

Leptin and its Relation to Autonomic Activity, Endothelial Cell Activation and Blood Pressure in a Young Black and White Population: The African-PREDICT study

An increasing prevalence of obesity-related hypertension is observed in the youth and may have severe consequences for future cardiovascular disease development. Previous studies portrayed leptin as a potential factor involved in obesity-related hypertension development. In order to understand leptin's contributions to early cardiovascular deterioration, we investigated leptin and its associations with measures of autonomic activity, endothelial activation, and blood pressure in young healthy black and white men and women. We included 820 participants (aged 20-30 years) and determined serum leptin and endothelial cellular adhesion molecules. We measured 24-h blood pressure, heart rate, and heart rate variability components. In multivariate-adjusted regression analyses, we found consistent associations between markers of autonomic activity (such as 24-h heart rate, day and night-time heart rate as well as heart rate variability total power) and leptin in both white (all p≤0.001) and black men (all p≤0.040). These findings were absent or less prominent in women, despite their almost 10-fold higher leptin levels than men. Only in white men, 24-h diastolic blood pressure was associated with leptin (Std β=0.37; p=0.006). This association was found to be partly mediated by autonomic activity (24-h heart rate variability total power). No independent associations were observed between leptin and markers of endothelial cell activation, irrespective of race or gender. Leptin's independent association with autonomic neural activity in a young apparently healthy population suggests an early influence of leptin on autonomic function and future blood pressure elevation especially in men.

Effect of Diazepam on 24-Hour Blood Pressure and Heart Rate in Healthy Young Volunteers

Aim: To assess the effects of evening chronic administration of diazepam on 24-h blood pressure (BP) and heart rate (HR) in healthy young adults. Methods: This randomized double blind, cross-over study evaluated the effects of diazepam 5 mg or placebo, both ingested in the evening, on 24-h ambulatory BP and HR in healthy subjects aged 21–30. Results: A total of 30 subjects were included in the analysis. At the end of 4-week diazepam intake, an increase in 24-h HR mean values was found (+5.2 beats/min, p < 0.05). Analysis of subperiods showed that diazepam produced a 10.1% increase in night-time HR (+6.1 beats/min, p < 0.01) without affecting BP. A significant HR rise (+4.9 beats/min, p < 0.05) and SBP reduction (–3.8 mm Hg, p < 0.05) were observed in the morning hours. The HR increase persisted in day-time hours (+4.6 beats/min, p < 0.05), while BP values resulted unaffected. Conclusions: In healthy subjects, diazepam taken as a hypnotic agent induces a significant HR increase, possibly mediated by a decrease in vagal tone. This effect might be of clinical relevance due to the role that HR plays as an independent cardiovascular risk factor.

Autonomic Dysfunction in Wilson's Disease: A Comprehensive Evaluation during a 3-Year Follow Up.

Objectives: Wilson's disease is reported to have autonomic dysfunction, but comprehensive evaluation of autonomic function is lacking. Additionally, little is known about the change of autonomic function of Wilson's disease during continuous therapy. We assumed that patients with Wilson's disease had both sympathetic and parasympathetic autonomic impairments, and the autonomic dysfunction might be stable across a 3-year follow-up after years of optimal treatment.Methods: Twenty-six patients with Wilson's disease and twenty-six healthy controls were recruited. Twenty patients in the Wilson's disease group were examined again after a 3-year follow-up. All the participants were evaluated by a questionnaire on dysautonomia symptoms, 24-h blood pressure and heart rate monitoring, and cardiovascular autonomic function examination in various conditions including at rest, deep breathing, Valsalva maneuver, isometric handgrip test and passive tilting. Baroreflex sensitivity and spectral analyses were performed via trigonometric regressive spectral analysis.Results: Patients with Wilson's disease showed autonomic dysfunction mainly in the following aspects: (1) the heart rate was higher than the controls. (2) Valsalva ratio was lower in patients with Wilson's disease compared with the controls. (3) Heart rate increase during isometric hand gripping was smaller in the Wilson's disease patients than the controls. (4) Baroreflex sensitivity was lower during nearly all the cardiovascular autonomic function examinations compared with healthy controls. When tested 3 years later, baroreflex sensitivity at rest decreased compared with baseline. (5) There were mild declines of resting DBP and low frequency component of heart rate variability during the follow-up examination compared with baseline. (6) Subgroup analysis showed that patients initially presenting with neurological symptoms had a higher night-time heart rate, lower expiration: inspiration RR interval ratio (E/I ratio), lower expiration: inspiration RR interval difference (E-I difference), less increase of heart rate and diastolic blood pressure during the handgrip test, and lower baroreflex sensitivity during deep breathing than the control group. (7) Correlation analysis showed that the severity of neurological symptoms was associated with E/I ratio, E-I difference, Valsalva ratio, heart rate change during the handgrip test, and baroreflex sensitivity during deep breathing.Conclusions: The present study reveals cardiovascular autonomic dysfunction involving both sympathetic and parasympathetic branches in Wilson's disease patients, which is especially significant in the patients with neurological onset. Autonomic function is generally stable undergoing optimal maintenance treatment in patients with Wilson's disease. Though there might be mild changes of specific parameters.

Blood pressure response to CPAP treatment in subjects with obstructive sleep apnoea: the predictive value of 24-h ambulatory blood pressure monitoring

The reduction in blood pressure (BP) with continuous positive airway pressure (CPAP) is modest and highly variable. In this study, we identified the variables that predict BP response to CPAP.24-h ambulatory BP monitoring (ABPM), C-reactive protein (CRP), leptin, adiponectin and 24-h urinary catecholamine were measured before and after 6 months of CPAP in obstructive sleep apnoea (OSA) patients.Overall, 88 middle-aged, obese male patients with severe OSA (median apnoea-hypopnoea index 42 events·h-1) were included; 28.4% had hypertension. 62 patients finished the study, and 60 were analysed. The daytime diastolic BP (-2 mmHg) and norepinephrine (-109.5 nmol·day-1) were reduced after CPAP, but no changes in the 24-h BP, night-time BP, dopamine, epinephrine, CRP, leptin or adiponectin were detected. The nocturnal normotension was associated with an increased night-time-BP (+4 mmHg) after CPAP, whereas nocturnal hypertension was associated with a reduction of 24-h BP (-3 mmHg). A multivariate linear regression model showed differential night-time BP changes after CPAP. Specifically, low night-time heart rate (<68 bpm) and BP dipper profile were associated with increased night-time BP and new diagnosis of nocturnal hypertension.Our results suggest that nocturnal hypertension, circadian BP pattern and night-time heart rate could be clinical predictors of BP response to CPAP and support the usefulness of 24-h ABPM for OSA patients before treatment initiation. These results need to be confirmed in further studies.

BP.11.05] URIC ACID AND HYPERTENSION. ROLE OF RENIN ANGIOTENSIN AND SYMPATHETIC NERVOUS SYSTEMS ACTIVITY

Objective: A number of studies have documented an association of serum uric acid (SUA) with risk of hypertension. We did a prospective study to investigate whether SUA was an independent predictor of risk of hypertension in the young and whether plasma renin activity (PRA) and office and ambulatory heart rates differed according to SUA tertile. Design and method: The study was conducted in a cohort of 1156 young-to-middle-age subjects screened for stage 1 hypertension and followed for a median of 11.4 years. Mean age was 33.0 ± 8.6 years and mean office blood pressure at screening was 145.3 ± 10.6/93.4 ± 5.8 mmHg. PRA was measured in 799 participants. In multivariable Cox analyses, data were adjusted for age, gender, body mass index, parental hypertension, 24-hour systolic and diastolic BP, serum creatinine, and lifestyle factors. Results: At follow-up end, 63.3% of study participants developed hypertension needing treatment. SUA was an independent predictor of future hypertension (p = 0.005). Participants with SUA >5.60 mg/dL (top tertile) had a 31% (95%CI, 6%-60%) increase in risk compared to those of the bottom tertile (SUA <4.32 mg/dL). Office heart rate, average 24-hour heart rate, and night-time heart rate significantly increased across SUA tertiles (p = 0.008, p = 0.033, and p = 0.007, respectively, for ANCOVA after adjusting for age, sex, and lifestyle factors). PRA adjusted for age, sex, smoking, coffee and alcohol use increased on going from the first to the third SUA tertile (mean ± SEM, 3.1 ± 0.5, 3.8 ± 0.4, and 4.9 ± 0.5 ng/ml/h, respectively, p = 0.038). Inclusion of physical activity in the model slightly attenuated the relationship (p = 0.044). PRA was lower in active than in sedentary participants (3.2 ± 0.7 versus 4.8 ± 0.4 ng/ml/h, p = 0.050) as were office and ambulatory heart rates (both p < 0.001). No association between SUA and risk of hypertension was found among the active participants (p = 0.71). Conclusions: In keeping with our previous results, these data confirm that SUA is an independent predictor of hypertension in young-to-middle-age subjects. This may be due to the unfavourable effect of SUA on several factors including sympathetic tone and renin-angiotensin-system activity. Regular physical activity can counteract these pathophysiological mechanisms and prevent the development of hypertension in hyperuricemic subjects.

Daily Heart Rate in Relation to Cardiorespiratory Fitness and Metabolic Syndrome in HIV+ Hispanic Adults

Daily heart rate (HR) is usually higher among HIV+ compared with HIV- adults, a possible aspect of chronotropic incompetence (CI) in this population. Low cardiorespiratory fitness (CRF) and metabolic syndrome (MetSyn) are prevalent among HIV+ adults, possibly influencing CI. However, information regarding 24-hr HR as an index of CI, and its association with CRF and MetSyn in this population is nonexistent. PURPOSE: To describe the association between CRF, MetSyn, and daily HR in a group of HIV+ and HIV- Hispanic adults in Puerto Rico. METHODS: Eighty-Nine adults (59-HIV+ and 30 HIV-) completed measurements of CRF (VO2 peak), 24-hr blood pressure and HR, and metabolic syndrome (fasting glucose and lipid profile, resting BP, waist circumference). T-tests were used to detect differences between groups, and correlation analyses to evaluate associations between variables. RESULTS: The proportion of low CRF based on age and sex, and MetSyn was not different between HIV+ and HIV-participants (56 vs. 40%; and 53 vs. 37%; P=0.2, respectively). However, 24-hr HR, daytime HR, and night-time HR were all significantly higher in HIV+ compared with HIV- participants (78.3±9.4 vs. 67.4±8.4, 81.9±9.9 vs. 69.7±8.6, 70.7±9.4 vs. 62.7±9.0 bpm, respectively, P<0.05 for all). VO2 peak was inversely correlated with 24-hr HR, daytime HR, and night-time HR in both groups (ρ= -0.40, -0.36, -0.49, P<0.05 for all). Considering CRF classification in each group, all HR measures were significantly lower among those with high CRF vs. low CRF regardless of HIV status (HIV+: 24-hr HR by CRF: low= 81.1±8.2 vs. high= 74.8±9.7 bpm, P=0.009; daytime HR: low=85.0±8.7 vs. high=78.0±10.2 bpm, P=0.006; night-time HR: low=72.8±8.7 vs. high=68.0±9.8 bpm, P=0.02) (HIV-: 24-hr HR by CRF: low= 72.1±4.4 vs. high= 64.2±9. bpm, P=0.009; daytime HR: low=74.1±4.9 vs. high=66.8±9.4 bpm, P=0.02; night-time HR: low=67.8±6.1 vs. high=59.2±9.1 bpm, P=0.008). No HR differences were observed by MetSyn in the HIV+ group, but HR measures in the HIV- group were lower in those without MetSyn. CONCLUSION: These results suggest that CRF but not MetSyn, influence daily HR in HIV+ participants, with potential impact on CI correction. Intervention studies must be conducted to confirm these results. Supported by: NIH/CTSA KL2-RR024151, NIH/NIMHHD 8U54MD 007587-03.

Is the blunted fall in nighttime heart rate a marker of subclinical cardiac damage?

Is the blunted fall in nighttime heart rate a marker of subclinical cardiac damage?

Masked tachycardia. A predictor of adverse outcome in hypertension.

The relative role of office heart rate (HR) and ambulatory HR for predicting major adverse cardiovascular events (MACEs) and mortality is not well known. Aim of this study was to investigate the association of white-coat tachycardia and masked tachycardia with MACE and mortality in hypertensive patients. We performed 24-h ambulatory blood pressure and HR monitoring in 7602 hypertensive patients (4165 men) aged 52 ± 16 years enrolled in six prospective studies in Italy, Japan, and Australia. Participants were divided into four groups: normal office and normal night-time HRs (N = 5238), white-coat tachycardia (N = 998), masked tachycardia (N = 796), and sustained tachycardia (N = 570). Median follow-up was 5.0 years. In age-and-sex-adjusted Cox model, using the normal HRs group as a reference, white-coat tachycardia was not a significant predictor of excess MACEs or all-cause death. In contrast, both masked tachycardia [hazard ratio, 95% confidence interval (CI); 1.40, 1.11-1.77] and sustained tachycardia (1.86, 1.44-2.40) were associated with risk of excess MACE. In addition, masked tachycardia (hazard ratio, 95% CI; 1.62, 1.14-2.29) but not sustained tachycardia (1.35, 0.83-2.19) was a significant predictor of excess mortality. These relationships held true in multivariable parsimonious Cox models including major risk factors. In these models, masked tachycardia remained an independent predictor of excess MACE (hazard ratio, 95% CI; 1.34, 1.06-1.71) and all-cause mortality (1.68, 1.18-2.41). The current study confirms that measurement of HR adds to the risk stratification for MACE and mortality and shows that an elevated night-time HR confers an increased mortality risk to hypertensive patients who have normal office HR.

Effects of liraglutide on cardiovascular risk factors in patients with type 1 diabetes.

We investigated the short-term effect of adding liraglutide 1.8 mg once daily to insulin treatment on cardiovascular risk factors in patients with type 1 diabetes. In total, 100 overweight (BMI ≥25 kg/m2 ) adult patients (age ≥18 years) with type 1 diabetes and HbA1c ≥ 8% (64 mmol/mol) were randomized to liraglutide 1.8 mg or placebo added to insulin treatment in a 24-week double-blinded, placebo-controlled trial. At baseline and after 24 weeks of treatment, 24-hour blood pressure and heart rate, pulse pressure, pulse wave velocity and carotid intima-media thickness were evaluated. Compared with placebo, liraglutide increased 24-hour heart rate by 4.6 beats per minute (BPM); P = .0015, daytime heart rate by 3.7; P = .0240 and night-time heart rate by 7.5 BPM; P < .001 after 24 weeks. Diastolic nocturnal blood pressure increased by 4 mm Hg; P = .0362 in the liraglutide group compared with placebo. In conclusion, in patients with long-standing type 1 diabetes, liraglutide as add-on to insulin increased heart rate and did not improve other cardiovascular risk factors after 24 weeks of treatment.

The relationship between heart rate variability and left ventricular layer-specific deformation in uncomplicated diabetic patients.

The aim of this study was to investigate heart rate variability (HRV) and left ventricular (LV) remodeling in uncomplicated diabetic patients. Furthermore, we sought to investigate the association between HRV indices and LV structural, functional and mechanical parameters. This cross-sectional study included 50 uncomplicated patients with type 2 diabetes and 40 healthy controls without cardiovascular risk factors. All study subjects underwent 24-h Holter monitoring, laboratory analyses and complete two-dimensional echocardiography examination (2DE). LV structure and diastolic function were significantly deteriorated in the diabetic patients comparing with the controls. LV global longitudinal, circumferential and radial strains were significantly reduced in the diabetic group. LV endocardial, mid-miocardial and epicardial longitudinal and circumferential strains were significantly decreased, whereas LV twist was significantly increased, in the diabetic patients; 24-h, daytime and nighttime heart rates were higher in the diabetic patients. All parameters of time and frequency domain of HRV were reduced in the diabetic subjects. LV mass index, mitral E/e' ratio and 2DE LV endocardial and mid-miocardial longitudinal and circumferential strains correlated with HRV parameters. A multivariate regression analysis showed that E/e' ratio and 2DE LV layer-specific strains were associated with HRV parameters independently of age, BMI, systolic blood pressure and LV mass index. HRV and LV mechanics are significantly deteriorated in uncomplicated diabetic individuals. Parameters of LV remodeling are independently associated with HRV indices, which could indicate the importance of HRV determination in diabetics.

Effects of Liraglutide on Heart Rate and Heart Rate Variability: A Randomized, Double-Blind, Placebo-Controlled Crossover Study.

Reduced heart rate variability (HRV) and increased heart rate (HR) have been associated with cardiovascular mortality. Glucagon-like peptide 1 receptor agonists (GLP-1 RAs) increase HR, and studies have suggested that they may reduce HRV. We examined the effect of the GLP-1 RA liraglutide on HRV and diurnal variation of HR in overweight patients with newly diagnosed type 2 diabetes (T2D) and stable coronary artery disease (CAD). Liraglutide or placebo was administrated to a backbone therapy of metformin in this double-blind, placebo-controlled 12 + 12-week crossover study. SD of beat-to-beat (NN) intervals (SDNN) was assessed by 24-h Holter monitoring as a measure of HRV. Diurnal HR variation and sympathovagal balance analyzed by root mean square of successive differences (RMSSD) in NN intervals and high-frequency (HF) and low-frequency (LF) power were assessed. Compared with placebo, liraglutide decreased SDNN in 27 subjects (-33.9 ms; P < 0.001, paired analysis); decreased RMSSD (-0.3 log-ms; P = 0.025); and increased the mean HR (8.1 beats/min; P = 0.003), daytime HR (5.7; P = 0.083), and nighttime HR (6.3; P = 0.026). In a multivariable regression analysis, the decrease in SDNN remained significant after adjustment for metabolic and HR changes. Liraglutide reduced HF power (-0.7 log-ms2; P = 0.026) without any change in LF/HF ratio. In overweight patients with CAD and newly diagnosed T2D, liraglutide increased HR and reduced HRV despite significant weight loss and improvement in metabolic parameters. The increase in nightly HR in conjunction with a decrease in parameters of parasympathetic activity suggests that liraglutide may affect sympathovagal balance.

MPS 10-06 Seasonal variations of 24-hour ambulatory blood pressure and blood pressure variability in the young and elderly essential hypertensive patients

Objective: Seasonal blood pressure (BP) changes has been described in clinic BP. Few studies have examined the seasonal variation in BP and BP variability, assessed by 24-hour ambulatory blood pressure monitoring (ABPM) and it remains uncertain whether the seasonal trend differs between young and elderly hypertensive patients. Design and Method: A total of 1028 untreated essential hypertensive patients (mean age 52 ± 14 years) who underwent 24-hour ABPM between January 2009 and April 2013 were enrolled. Patients were divided into young (age ≤ 70 years, n = 927) and elderly (age > 70 years, n = 101) groups. Results: Compared to elderly group, young age group had higher clinic, 24-hour, daytime and night-time diastolic BP (DBP), higher clinic, 24-hour and daytime heart rate (HR), higher 24-hour and daytime HR variability (HRV), lower night-time systolic BP (SBP) and daytime SBP variability. In young age group, significant seasonal variation of clinic DBP and daytime SBP variability with a peak in autumn, and nighttime DBP and HR with a peak in spring and the increased prevalence of non-dippers in summer were observed. On the other hand, elderly group demonstrated seasonal variation of clinic, 24-hour, daytime and nighttime HR with a peak in autumn, daytime DBP with a peak in winter and night-time SBP variability with a peak in summer. Conclusions: There was an apparent seasonal variation of DBP, HR and SBP variability in both young and elderly hypertensive patients. However, elderly patients showed more pronounced seasonal change in HR compared to younger patients.

PS 17-54 EFFECTS OF CILNIDIPINE VERSUS ATENOLOL ON LEFT VENTRICULAR DIASTOLIC FUNCTION AND HYPERTROPHY IN ESSENTIAL HYPERTENSION - CANDLE TRIAL

Objective: Effects of Cilnidipine versus Atenolol on Left Ventricular Diastolic Function and Hypertrophy in Essential Hypertension (CANDLE) study was designed as a prospective, randomized, double-blind, parallel-group to test whether cilnidipine achieves greater left ventricular (LV) mass reduction and improves LV diastolic function than does atenolol. Design and method: Seventy-two patients with uncomplicated essential hypertension and increased LV mass index at screening echocardiography (55 ± 2 years; 59% male; BP 157 ± 4/99 ± 3 mmHg) were enrolled and were randomly assigned and forced-titrated to 20 mg/d cilnidipine or 100 mg of atenolol treatment for 36 weeks. Echocardiography, 24-hours ambulatory blood pressure monitoring, biochemical studies including N-terminal pro-B-type natriuretic peptide and 24-hours urine protein and microalbumin were measured at baseline and after 36-weeks therapy. Results: Clinical examination and blinded echocardiogram in a per-protocol analysis of 28 cilnidipine-treated and 26 atenolol-treated patients revealed similar reductions in systolic/diastolic pressure (−16.5/8.9 versus −23.9/14.8 mmHg, both P > 0.05) and LV mass index (−21.4 versus −19.5 g/m2, both P > 0.05). No significant between-treatment difference was detected in population subsets defined by monotherapy treatment, sex, age, or severity of baseline hypertrophy. Similarly, there was no between-treatment difference in change in biochemical parameters. As we expected, cilnidipine-treated group showed lesser reduction on night-time heart rate (−2.4 versus −5.6 %, p = 0.021) rather than atenolol-treated group. Interestingly, cilnidipine-treated group showed reduction on left atrial (LA) volume index but on the contrary, atenolol-treated group showed more enlarged LA after treatment (−5.1 versus 7.3 %, p = 0.035). Conclusions: Both cilnidipine and atenolol similarly and effectively reduced blood pressure and LV mass index. However, only cilnidipine reduced LA volume index, whereas atenolol increased. Cilnidipine may provide more beneficial effect on the management in essential hypertension with diastolic dysfunction.

Effects of cigarette smoking on ambulatory blood pressure, heart rate, and heart rate variability in treated hypertensive patients

ABSTRACTWe investigated the influence of cigarette smoking on the levels and circadian patterns of blood pressure (BP), heart rate (HR), and HR variability (HRV) in hypertensive patients. Sixteen hypertensive smokers (57 ± 2 years old) receiving antihypertensive treatments participated in this study. Ambulatory monitoring of BP, HR, and electrocardiograms was performed every 30 min for 24 hours on a smoking day and nonsmoking day in a randomized crossover manner. Average 24-hour BP and daytime BP were significantly higher in the smoking period than in the nonsmoking period. No significant differences were observed in nighttime BP between the two periods. Average 24-hour and daytime HR, but not nighttime HR, were also higher in the smoking period than in the nonsmoking period. The daytime high frequency (HF) component of HRV was attenuated more in the smoking period than in the nonsmoking period. No significant differences were observed in the low frequency (LF) components of HRV or LF/HF ratio between the two periods. These results demonstrated that cigarette smoking increased the daytime and average 24-hour BP and HR, and the increases observed in daytime BP and HR were associated with the attenuation of parasympathetic nerve activity.

Hyperinsulinemia and obese phenotype differently influence blood pressure in young normotensive patients with polycystic ovary syndrome.

To differentiate the impact of insulin levels/resistance per se from that of excess weight on blood pressure (BP) daily changes, we evaluated, using 24-h ambulatory blood pressure monitoring (ABPM), systolic blood pressure (SBP) and diastolic blood pressure (DBP) in a cohort of young normotensive patients affected by polycystic ovary syndrome (PCOS). A cross-sectional study was performed. Fifty-four patients were studied according to (a) insulinemic state: 32 hyperinsulinemic and/or insulin-resistant (h-INS) and 22 normoinsulinemic (n-INS) patients; and (b) body mass index (BMI): 22 obese (BMI>30) and 32 lean (18.0<BMI<24.9) patients. Each subject's SBP and DBP and heart rate (HR) were measured by ABPM. Supine and upright plasma renin activity (PRA), and aldosterone levels were also assayed. Patients in the h-INS group showed higher 24-h, daytime, and nighttime diastolic blood pressure (DBP), higher nighttime systolic blood pressure (SBP) levels, as well as an increased 24-h, daytime and nighttime HR, compared to both obese and lean patients in the n-INS group. In relation to BMI, only 24-h, daytime, and nighttime DBP were higher in obese than in lean patients. At variance, when both h-INS and obesity were considered, 24-h SBP and DBP were higher in h-INS obese subjects than in the other groups. In multivariate analysis, insulin (max peak), area under the curve of insulin and insulin sensitivity index was independently associated with SBP. (1) Within a normotensive range, hyperinsulinemia and/or insulin resistance influence daily BP variation more than obesity does, suggesting a pivotal role of insulin on BP control in PCOS; (2) altered insulinemic state and ABPM-derived higher nighttime BP and HR may represent early markers to identify PCOS subjects prone to high cardiovascular risk.