Association between circadian rhythm of blood pressure and glucose tolerance status in normotensive, non-diabetic subjects

Determinants of reverse dipping blood pressure in normotensive, non-diabetic population with an office measurement below 130/85mmHg

Objective: The role of dipping blood pressure pattern in normotensives is unclear. The study aims to search the circadian blood pressure rhythm and the clinical determinants related to reverse dipping pattern in a strictly selected, normotensive population.Methods: The study population was divided into three groups depending on the nocturnal dipping pattern as dipping, non-dipping, and reverse dipping. Basal clinical characteristics, anthropometric measurements, and spot urine samples from the first-morning void were collected. Clinical determinants related to the presence of reverse dipping pattern were tested by the Multiple Binary Logistic Regression analysis.Results: A total of 233 participants were involved in the study population (median age 45 years [40-50]). Dipping pattern was detected in 55.4%, non-dipping pattern in 33.0%, and reverse dipping pattern in 11.6% of the study population. There was no difference between the groups in terms of basal clinical features. Albumin-to-creatinine ratio (ACR) (p < .001) and hs-CRP levels (p = .006) were also statistically significant across the groups. ACR (HR: 1.195, 95% CI: 1.067-1.338, p = .002) and hs-CRP (HR: 2.438, 95% CI: 1.023-5.808, p = .044) were found to be related to the presence of reverse dipping blood pressure pattern.Conclusions: The absence of nocturnal physiological dipping is seen at a remarkable rate in the normotensive Turkish population. ACR and hs-CRP are the clinical determinants related to the presence of reverse dipping blood pressure pattern.

Impact of Pediatric Obesity on Diurnal Blood Pressure Assessment and Cardiovascular Risk Markers

Background: The prevalence of hypertension is increasing particularly among obese children and adolescents. Obese children and adolescents with hypertension are likely to remain hypertensive as they reach adulthood and hypertension is linked to an increased risk for cardiovascular disease. Twenty-four-hour ambulatory blood pressure monitoring (ABPM) has become one of the most important tools in diagnosing hypertension in children and adolescents and circadian patterns of blood pressure may be important disease-risk predictors. Methods: A retrospective chart review was conducted in patients aged 6-21 years who underwent 24-h ABPM at Kentucky Children's Hospital (KCH) from August 2012 through June 2017. Exclusion criteria included conditions that could affect blood pressure including chronic kidney disease and other renal abnormalities, congenital heart disease, cancer, and thyroid disease. Subjects were categorized by body mass index into normal (below 85th percentile), overweight (85th-95th percentile), stage I obesity (95th-119th percentile), stage II obesity (120th-139th) and stage III obesity (>140th). Non-dipping was defined as a nocturnal BP reduction of <10%. Results: Two hundred and sixty-three patients (156 male patients) were included in the analysis, of whom 70 were normal weight, 33 overweight, 55 stage I obesity, 53 stage II, and 52 stage III obesity. Although there was no significant difference between normal weight and obese groups for prevalence of hypertension, there was a greater prevalence of SBP non-dipping in obese patients as BMI increased (p = 0.008). Furthermore, non-dippers had a significantly elevated LVMI as well as abnormal lab values for uric acid, blood lipid panel, creatinine, and TSH (p < 0.05). Conclusions: These findings demonstrate that obese children and adolescents constitute a large proportion of hypertensive children and adolescents and the severity of pediatric obesity is associated with nocturnal BP non-dipping. Additionally, obesity in children is linked to several cardiovascular risk factors including left ventricular hypertrophy, dyslipidemia, and elevated uric acid levels. Further studies utilizing ABPM measures on risk stratification in this very high-risk population are warranted.

Glucose abnormalities associated with impaired nocturnal fall in blood pressure in normotensive severely obese patients

BACKGROUND

The purpose of this study was to identify factors affecting the nocturnal decline in blood pressure (BP) in severe obesity.

METHODS

Clinical, biochemical, polysomnographic data, glucose tolerance status, and body fat composition were obtained in 82 candidates for bariatric surgery (mean age: 40 (11) years; BMI: 46 (4)kg/m(2)). To determine the nocturnal BP fall we used 24-h ambulatory BP monitoring to measure the magnitude (Δ) of nocturnal decline, the % day-night systolic BP (SBP) and diastolic BP (DBP), dipper status and nocturnal hypertension (HT).

RESULTS

Twenty-three percent of patients had nocturnal HT. Sixty percent had non dipper status, of which 95% had nocturnal HT. No specific factors were associated with the average 24-h SBP and DBP. Having glucose abnormalities was of primary importance for all variables evaluating nocturnal BP decline independent of daytime BP levels and severity of obesity. In comparing patients with or without glucose tolerance abnormalities, the night-time SBP and DBP were significantly higher and the Δ nocturnal decline and % day-night in both SBP and DBP were significantly lower in those with glucose tolerance abnormalities. In an adjusted multivariate model, having both glucose abnormalities and nocturnal HT remained associated with non dipper status with an OR of 3.13 (95% CI 1.11-8.87, p=0.03) and 14.93 (95% CI 1.77-125.62, p=0.001), respectively.

CONCLUSION

In normotensive severely obese patients, non dipper status and nocturnal HT are common, and the presence of glucose abnormalities was the primary variable associated with impaired nocturnal fall in BP.

Primary non-alcoholic fatty liver disease in hypertensive patients

BACKGROUND

Non-alcoholic fatty liver disease (NAFLD) is considered the most common liver disease affecting 15-25% of the general population.

AIMS

The aim of this study was to investigate the prevalence of NAFLD and the relationship between insulin sensitivity and NAFLD in grade III high and very high cardiovascular additional risk essential hypertensive patients according to the circadian blood pressure (BP) rhythm.

METHOD

This four-year prospective study was conducted at the Department of Internal Medicine at Cluj-Napoca's Diagnosis and Treatment Centre in Romania. The study included grade III essential hypertensive patients. Hypertensive patients were divided into four groups according to the diurnal index (DI) from ABPM monitoring: dipper (D), non-dipper (ND), reverse-dipper (RD), and extreme-dipper (ED). All hypertensive patients underwent 24 ABPM, blood tests and abdominal ultrasonography for the diagnosis of fatty liver disease.

RESULTS

Thirty-five hypertensive patients were included in the study, with 31.42% ND, 11.43% RD, 8.57% ED and 48.57% D. The prevalence of NAFLD was significantly higher in ND, RD and ED when compared to D. When compared to the dipper group of hypertensive patients a statistically significantly higher level of plasma insulin was observed: in non-dipper [86.3±17.9pmol/l vs. 62.2±203pmol/l, p<0.05], in reverse dipper [88.3±18.6pmol/l vs. 62.2±20.3pmol/l] and in extreme-dippers [86.7±16.88pmol/l vs. 62.2±20.3 pmol/l, p<0.05].

CONCLUSION

The altered dipping status (ND, RD, ED) of hypertension associated with a higher insulin resistance could be the pathogenetic link between the NAFLD and altered blood pressure status. Altered BP status could be a marker of NAFLD in hypertensive patients.

Non-dipping nocturnal blood pressure in psoriasis vulgaris

BACKGROUND

Psoriasis vulgaris is one of the most prevalent chronic, inflammatory skin disorders. Patients with psoriasis carry an excess risk of hypertension and adverse cardiovascular (CV) events. Blood pressure (BP) has a circadian rhythm characterised with lower values at night. A blunted nocturnal BP decline defined as non-dipping accelerates the development of hypertension and CV diseases. The aim of this study is to evaluate circadian variation of blood pressure in normotensive middle-aged patients with psoriasis vulgaris.

METHODS

Seventy adult patients with psoriasis vulgaris (group 1) and 70 age and sex-matched healthy individuals (group 2) were included in the study. Ambulatory BP monitoring was performed in all participants over a 24-h period. Non-dippers are defined as those who show a reduction in BP of less than 10 % between the average day and night systolic BP.

RESULTS

Although mean 24-h BPs were similar in both groups, night-time BPs were significantly higher in psoriatic patients (115.1 ± 7.7 vs. 109.9 ± 6.0 mmHg and 72.1 ± 7.0 vs. 67.6 ± 5.5 mmHg, respectively; p < 0.05). The non-dipping pattern of BP changes was significantly more common in patients with psoriasis vulgaris compared with the control group (65.9 vs. 34.1 %, p < 0.01). Psoriasis severity and BMI are independent predictors of impaired nocturnal BP regulation.

CONCLUSIONS

Patients with psoriasis vulgaris had increased nocturnal BP and heart rate. This is the first study to demonstrate a blunted nocturnal BP decrease in normotensive patients with psoriasis.

Elevated myocardial repolarization lability and arterial baroreflex dysfunction in healthy individuals with nondipping blood pressure pattern

BACKGROUND

The "nondipping" pattern (NDP) of blood pressure, characterized by the absence of the reduction in blood pressure (BP) that typically takes place during the night time, has been associated with elevated cardiovascular morbidity, including stroke, myocardial infarction, and sudden cardiac-related death. In various cardiovascular diseases, reduced vagal control of cardiac function and elevated lability of cardiac repolarization have been associated with increased risk for ventricular arrhythmia and sudden death. The aim of this study was to assess temporal QT variability, arterial baroreflex sensitivity (BRS), and baroreflex effectiveness index (BEI) in two groups of otherwise healthy subjects, one group consisting of those with a normal BP pattern and the other with a nondipping BP pattern.

METHODS

Ninety-five healthy subjects underwent 24-h ambulatory BP (AMBP) monitoring. A minimum of 10% reduction in BP during the night relative to daytime levels is considered normal (as found in "dippers"). These individuals were classified as "dippers" (n = 59) and individuals without 10% reduction in BP during night were classified as "nondippers" (n = 36). Electrocardiogram (ECG) readings and beat-to-beat BP were recorded at 1,000 Hz with the subjects at rest in the supine posture for 20 min. BRS, BEI, and QT variability index (QTVI) were calculated.

RESULTS

There were no differences between the study groups with respect to age, gender, and average BP. Nondippers showed an increase in QTVI (-1.28 +/- 0.48 in nondippers vs. -1.52 +/- 0.29 in dippers, P < 0.05) and a decrease in BEI (0.34 +/- 0.17 in nondippers vs. 0.43 +/- 0.17 in dippers, P < 0.05), whereas BRS did not differ between the groups.

CONCLUSION

A nondipping BP pattern in healthy subjects is associated with elevated myocardial repolarization lability and impaired baroreflex function, suggesting dysfunction of the autonomic nervous system.

Non-dipping pattern in ambulatory blood pressure monitoring is associated with metabolic abnormalities in a random sample of middle-aged subjects

A reduction in the blood pressure decline at night (<10% from daytime systolic blood pressure (SBP)) during 24-h ambulatory blood pressure monitoring (ABPM) ('non-dipping pattern') is associated with cardiovascular morbidity. Our aim was to evaluate whether ABPM characteristics are associated with metabolic abnormalities in subjects without known hypertension or type 2 diabetes mellitus (T2DM). This is a cross-sectional population-based study on middle-aged subjects (n=462). Two distinct definitions of metabolic syndrome (MetS) were used: National Cholesterol Education Program-Third Adult Treatment Panel (NCEP-ATPIII) and International Diabetes Federation (IDF) criteria. Results suggested that subjects characterized by non-dipping in 24 h ABPM were more obese (P=0.014). After adjustment for body mass index, age and sex, non-dippers had higher very-low-density lipoprotein (VLDL)-cholesterol (P=0.003), total (P=0.029)-and VLDL-triglycerides (P=0.026) and oral glucose tolerance test 2 h blood glucose (P=0.027) compared with dippers. Non-dipping status was more common among subjects with MetS (P< or =0.01), impaired glucose tolerance (IGT) (P<0.05) and in those with the combination of IGT-T2DM (P< or =0.01) than among those without these abnormalities. ABPM non-dipping status was an independent predictor of IGT in multivariate models (P<0.05). With respect to MetS components, high triglycerides (P< or =0.005) and low high density lipoprotein-cholesterol (P<0.05) were associated with a non-dipping pattern. The percentage decline in blood pressure from day to night decreased with the number of metabolic abnormalities (P=0.012). In conclusion, ABPM non-dipping status is an independent predictor of glucose intolerance. It is also associated with several other metabolic abnormalities. Whether non-dipping pattern is causally related to these metabolic aberrations remains to be explored in a future prospective follow-up of this cohort.