Serum uric acid, inflammation, and nondipping circadian pattern in essential hypertension

Efficacy of angiotensin receptor blockers for nocturnal blood pressure reduction: a systematic review and meta-analysis

BACKGROUND

Nocturnal blood pressure (BP) is correlated with an increased risk of cardiovascular events and is an important predictor of cardiovascular death in hypertensive patients.

OBJECTIVE

Nocturnal BP control is of great importance for cardiovascular risk reduction. This systematic review and meta-analysis aimed to explore the efficacy of angiotensin receptor blockers (ARBs) for nocturnal BP reduction in patients with mild to moderate hypertension.

METHODS

PICOS design structure was used to formulate the data extraction. All statistical calculations and analyses were performed with R.

RESULTS

Seventy-seven studies with 13,314 participants were included. The overall analysis indicated that nocturnal BP drop varied considerably among different ARBs. Allisartan (13.04 [95% CI (-18.41, -7.68)] mmHg), olmesartan (11.67 [95% CI (-14.12, -9.21)] mmHg), telmisartan (11.11 [95% CI (-12.12, -10.11)] mmHg) were associated with greater reduction in nocturnal systolic BP. In the aspect of the nocturnal-diurnal BP drop ratio, only allisartan was greater than 1. While, the variation tendency of last 4-6 h ambulatory BP was basically consistent with nocturnal BP. Additionally, allisartan showed improvement effect in the proportion of patients with dipping BP pattern.

CONCLUSIONS

This study demonstrates that for patients with mild to moderate hypertension, allisartan, olmesartan and telmisartan have more advantages in nocturnal BP reduction among the ARBs, while allisartan can reduce nighttime BP more than daytime BP and improve the dipping pattern.

Blood Pressure Patterns and Hepatosteatosis: Cardiometabolic Risk Assessment in Dipper and Non-Dipper Phenotypes

Background/Objectives: Non-dipper hypertension (HT), a condition in which blood pressure does not drop sufficiently at night compared to daytime, is considered a serious condition that increases the risk of cardiovascular disease, stroke, and organ damage. This study aimed to examine the relationship between dipper and non-dipper blood pressure patterns, hepatosteatosis, and biochemical markers in hypertensive and normotensive individuals. Methods: Demographic, biochemical, and hepatic ultrasonography data from 142 patients who underwent 24 h ambulatory blood pressure measurement (ABPM) were evaluated retrospectively and cross-sectionally in this study. Patients were categorized into four groups based on ABPM results: non-dipper normotensive (NDN), dipper normotensive (DN), non-dipper hypertensive (NDH), and dipper hypertensive (DH). Results: The study results indicate that NDH individuals had markedly elevated levels of hepatosteatosis and uric acid compared with DH and normotensive persons (p < 0.001). The grade of hepatosteatosis showed significant discriminatory capacity in differentiating between dipper and non-dipper hypertensive patients, with an AUC of 0.861, specificity of 94%, and sensitivity of 66%. Individuals with hypertension exhibiting a non-dipper pattern demonstrate a greater prevalence of hepatosteatosis and elevated uric acid levels. Conclusions: The study findings show non-dipper patterns have a higher risk for cardiometabolic diseases. This indicates that not only blood pressure, but also metabolic disorders should be closely monitored and treated in the management of non-dipper HT.

Inflammation-based markers, especially the uric acid/albumin ratio, are associated with non-dipper pattern in newly diagnosed treatment-naive hypertensive patients

OBJECTIVE

Physiologically, at night, blood pressure (BP) is expected to decrease by at least 10% in hypertensive individuals. The absence of this decrease, called non-dipper hypertension, is associated with increased end-organ damage and cardiovascular mortality and morbidity in hypertensive individuals. It is known that increased inflammatory process plays an important role in the etiopathogenesis of non-dipper hypertension pattern. In recent years, it has been shown that inflammation-based markers (IBMs) obtained by combining various inflammation-related hematological and biochemical parameters in a single fraction have stronger predictive value than single inflammatory parameters. However, until now, there has not been a study investigating the relationship of these markers with dipper/non-dipper status in newly diagnosed hypertensive patients.

METHODS

Based on ambulatory BP monitoring, 217 dipper and 301 non-dipper naive hypertensive subjects were included in this study. All subjects' IBM values were compared between dipper and non-dipper hypertensive individuals.

RESULTS

IBMs [C-reactive protein/albumin ratio (CAR), monocyte/high-density lipoprotein cholesterol ratio (MHR), neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio, systemic immune-inflammation index (SII), uric acid/albumin ratio (UAR)] were significantly higher in the non-dipper group. CAR, MHR, NLR, SII, and UAR were determined as independent predictors for non-dipper pattern ( P  < 0.05, for all). Also, UAR's diagnostic performance for non-dipper pattern was found to be superior to other IBMs (area under the curve: 0.783, 95% confidence interval: 0.743-0.822; P  < 0.001).

CONCLUSION

These findings suggest an association between elevated IBMs, particularly UAR, and the non-dipper hypertension pattern observed in our study.

Hyperuricemia: An Intriguing Connection to Metabolic Syndrome, Diabetes, Kidney Disease, and Hypertension

PURPOSE OF THE REVIEW

Our review explores the epidemiology, physiology, and clinical data surrounding the connection between hyperuricemia and metabolic syndrome, chronic kidney disease, and hypertension.

RECENT FINDINGS

Compelling physiologic mechanisms have been proposed to explain a causal relationship between hyperuricemia and metabolic syndrome, chronic kidney disease, and hypertension but clinical studies have given mixed results in terms of whether intervening with hyperuricemia using urate-lowering therapy has any beneficial effects for patients with these conditions. Despite the large amount of research already put into this topic, more randomized placebo-controlled trials are needed to more firmly establish whether a cause-effect relationship exists and whether lowering uric acid levels in patients with these conditions is beneficial.

Establishment of a potent weighted risk model for determining the progression of diabetic kidney disease

BACKGROUND

Diabetic kidney disease (DKD) is a severe complication of diabetes. Currently, no effective measures are available to reduce the risk of DKD progression. This study aimed to establish a weighted risk model to determine DKD progression and provide effective treatment strategies.

METHODS

This was a hospital-based, cross-sectional study. A total of 1104 patients with DKD were included in this study. The random forest method was used to develop weighted risk models to assess DKD progression. Receiver operating characteristic curves were used to validate the models and calculate the optimal cutoff values for important risk factors.

RESULTS

We developed potent weighted risk models to evaluate DKD progression. The top six risk factors for DKD progression to chronic kidney disease were hemoglobin, hemoglobin A1c (HbA1c), serum uric acid (SUA), plasma fibrinogen, serum albumin, and neutrophil percentage. The top six risk factors for determining DKD progression to dialysis were hemoglobin, HbA1c, neutrophil percentage, serum albumin, duration of diabetes, and plasma fibrinogen level. Furthermore, the optimal cutoff values of hemoglobin and HbA1c for determining DKD progression were 112 g/L and 7.2%, respectively.

CONCLUSION

We developed potent weighted risk models for DKD progression that can be employed to formulate precise therapeutic strategies. Monitoring and controlling combined risk factors and prioritizing interventions for key risk factors may help reduce the risk of DKD progression.

Factors Associating with Non-Dipping Pattern of Nocturnal Blood Pressure in Patients with Essential Hypertension

Background: In patients with essential hypertension, a non-dipping blood pressure pattern is a strong risk factor for cardiovascular diseases. However, background factors associating with such a blood pressure pattern remain unknown. Methods: Untreated essential hypertensive patients without chronic kidney diseases who were admitted to our outpatient clinic were included. Blood sampling and 24 h ambulatory blood pressure monitoring were mandatorily performed. Non-dipper status was defined as a maximum decrease in nocturnal systolic blood pressure within 10%. Clinical factors associating with non-dipper status were investigated. Results: A total of 154 patients (56 ± 12 years old, 86 men) were included. Among baseline characteristics, a higher serum uric acid level was independently associated with non-dipper status (odds ratio 1.03, 95% confidence interval 1.00−1.05, p < 0.05). Among those with non-dipper status, a higher high-sensitivity C-reactive protein level tended to be associated with incremental nighttime systolic blood pressure levels (p = 0.065). Conclusions: Hyperuricemia and micro-inflammation might be associated with attenuated nocturnal blood pressure dipping and incremental nighttime systolic blood pressure levels.

The relationship between nondipper hypertension and triglyceride glucose index

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

Therapeutic Usefulness of a Novel Calcium Channel Blocker Azelnidipine in the Treatment of Hypertension: A Narrative Review

The prevalence of hypertension and comorbidities such as metabolic syndrome, diabetes mellitus, and chronic kidney disease in India is alarmingly high. Amlodipine, an older-generation calcium channel blocker (CCB), is currently the gold standard for hypertension management in India. However, it has several disadvantages, including reflex tachycardia and pedal edema. Therefore, an effective antihypertensive agent that does not cause these adverse effects and provides end-organ protection is required for the holistic management of hypertension in the country. Azelnidipine is a new-generation CCB that has recently been approved for the treatment of hypertension in India. This review provides an overview of the utility of azelnidipine for hypertension control, including comparisons with traditional CCBs such as amlodipine. It discusses the key antihypertensive effects of azelnidipine as well as its advantages in the prevention of tachycardia and associated complications. In addition, this review highlights the extensive cardio- and renoprotective activities of azelnidipine, including its effects on systolic and diastolic function and urinary albumin excretion. Overall, this substantial body of evidence supports the use of azelnidipine for the treatment of hypertension, especially in India. It suggests that the adoption of azelnidipine as the new gold standard CCB could help India battle its hypertension epidemic.

Association between international index of erectile function-5 scores and circadian patterns of newly diagnosed hypertension in erectile dysfunction patients

By the beginning of this study in 2019, it was known that hypertension is a risk factor for erectile dysfunction, and also, there are circadian changes that occur in blood pressure. Further, non-dipping hypertension is known to be linked to poor cardiac outcomes and erectile functions, so the research described in this article was initiated with an aim to explore the potential relationship between erectile dysfunction and circadian patterns of newly diagnosed hypertension. Between April 2019 and May 2022, 583 patients aged 30-70 years were diagnosed with erectile dysfunction (ED) in our outpatient clinic. Applying our exclusion criteria to 583 patients, a group of 371 patients left with us; these patients were referred to the cardiology clinic for hypertension evaluation with consecutive ambulatory blood pressure monitoring (ABPM). Data were collected for the study prospectively. Of the 371 patients evaluated with ABPM, 125 had newly diagnosed hypertension (mean BP ≥135/85 mmHg in ABPM). These patients were divided into two groups according to the pattern of hypertension identified in ABPM: dippers (Group D) and non-dippers (Group ND). They were then compared using clinical and laboratory findings, including erectile function scores. While the number of patients in the ND group was 83, the number in the D group was 42. In the ND group, the mean age was higher (59 ± 10 vs. 54 ± 12, p = 0.0024). IIEF-5 (international index of erectile function) scores were determined to be significantly lower in the ND group (14.4 ± 4.9 vs. 11.5 ± 4.6, p = 0.001). Also, serum creatinine levels were higher in Group ND than in D (0.96 ± 0.12 vs. 1 ± 0.15, p = 0.001). In our multivariate analysis, IIEF-5 scores (OR: 0.880, 95% CI: 0.811-0.955; p = 0.002) and serum creatinine levels (OR: 1027, 95% CI: 1003-1052; p = 0.025) were found to be independent risk factors of non-dipper HT. The cut-off value of the IIEF-5 score for non-dipper HT in a ROC curve analysis was 13.5 with 64.3% sensitivity and 66.1% specificity (area under curve value: 0.673 [95% CI: 0.573-0.772, p < 0.001]). This study showed that, in patients with ED, the non-dipper pattern was associated with poorer erectile function when HT was newly diagnosed. We also found that the severity of erectile dysfunction is an independent marker for non-dipper HT.

Fatty Acid Levels and Their Inflammatory Metabolites Are Associated with the Nondipping Status and Risk of Obstructive Sleep Apnea Syndrome in Stroke Patients

Background: This paper discusses the role of inflammation in the pathogenesis of nondipping blood pressure and its role in the pathogenesis of obstructive sleep apnea syndrome. The aim of the study was to assess the impact of free fatty acids (FAs) and their inflammatory metabolites on the nondipping phenomenon and the risk of sleep apnea in stroke patients. Methods: Sixty-four ischemic stroke patients were included in the prospective study. Group I consisted of 33 patients with a preserved physiological dipping effect (DIP), while group II included 31 patients with the nondipping phenomenon (NDIP). All subjects had FA gas chromatography and inflammatory metabolite measurements performed with the use of liquid chromatography, their 24 h blood pressure was recorded, and they were assessed with the Epworth sleepiness scale (ESS). Results: In the nondipping group a higher level of C16:0 palmitic acid was observed, while lower levels were observed in regard to C20:0 arachidic acid, C22:0 behenic acid and C24:1 nervonic acid. A decreased leukotriene B4 level was recorded in the nondipping group. None of the FAs and derivatives correlated with the ESS scale in the group of patients after stroke. Correlations were observed after dividing into the DIP and NDIP groups. In the DIP group, a higher score of ESS was correlated with numerous FAs and derivatives. Inflammation of a lower degree and a higher level of anti-inflammatory mediators from EPA and DHA acids favored the occurrence of the DIP. A high level of C18: 3n6 gamma linoleic acid indicating advanced inflammation, intensified the NDIP effect. Conclusions: We demonstrated potential novel associations between the FA levels and eicosanoids in the pathogenesis of the nondipping phenomenon. There are common connections between fatty acids, their metabolites, inflammation, obstructive sleep apnea syndrome and nondipping in stroke patients.

Association Between Serum Uric Acid Levels and Traditional Cardiovascular Risk Factors in Xiamen Residents of China: A Real-World Study

Background

Serum uric acid (SUA) levels was associated with cardiovascular diseases and cardiovascular events. However, the relationship between SUA levels and traditional cardiovascular risk factors has not been well-established among Xiamen residents. Our study aimed to estimate the relationship between SUA levels and cardiovascular risk factors among Xiamen residents using real-world data.

Methods

Participants were enrolled from eight community health service centers in Xiamen, China. Participants were divided into four groups according to quartiles of the SUA levels. The history of diseases, the use of medications and the levels of laboratory parameters were collected. The China-PAR equation was used to evaluate the 10-year atherosclerotic cardiovascular disease (ASCVD) risk.

Results

A total of 1,322 participants were enrolled. About 568 (43.0%) were men and 754 (57.0%) were women. The prevalences of hypertension, elderly, current smokers, and obesity were higher in the quartile 4 (Q4) group than the quartile 1 (Q1) group (all p < 0.001). Multivariable logistic regression analysis showed the OR for hypertension was 2.671 (95% CI 1.777–4.015, p < 0.001) in the Q4 group compared with that in the Q1 group. Further logistic regression showed the OR for hypertension was 3.254 (95% CI 1.756–6.031, p < 0.001) in men and 2.314 (95% CI 1.354–3.955, p = 0.002) in women in the Q4 group compared with that in the Q1 group, respectively. In addition, the percentage of participants with low 10-year ASCVD risk calculated by China-PAR was higher in the Q1 group than that in the Q4 group (55.86 vs. 31.82%, p < 0.001). The percentage of participants with high 10-year ASCVD risk was lower in the Q1 group compared with the Q4 group (15.32 vs. 25.45%, p < 0.001). Multiple linear logistic regression showed the 10-year China-PAR ASCVD risk scores was positively correlated with SUA after adjusting for various factors (β = 0.135, p = 0.001).

Conclusion

Serum uric acid was associated with several cardiovascular risk factors in Xiamen residents. The percentage of high 10-year ASDVD risk was higher in participants with hyperuricemia. Participants with hyperuricemia may experience cardiovascular benefit from uric acid-lowering therapy.

High Levels of Thromboxane (TX) Are Associated with the Sex-Dependent Non-Dipping Phenomenon in Ischemic Stroke Patients

BACKGROUND

Inflammation and high blood pressure (nondipping profile) during the rest/sleep period have been associated with an effect on the incidence of cardiovascular disorders and a more severe course in the ischemic cerebrovascular event. There are no available data on the relationship between dipping status and the pro-inflammatory metabolites of arachidonic acid (AA); therefore, we undertook a study to investigate the influence of thromboxane on the incidence of nondipping among patients after stroke.

METHODS

Sixty-two patients with ischemic stroke (including 34 women and 28 men) were tested for the involvement of thromboxane in the nondipping phenomenon. Subjects were analyzed for the presence of the physiological phenomenon of dipping (DIP group) versus its absence-nondipping (NDIP group). Thromboxane (TX) measurements were performed using liquid chromatography, and blood pressure was measured 24 h a day in all subjects.

RESULTS

The analysis of the thromboxane level in the plasma of patients after ischemic stroke showed significant differences in terms of sex (p = 0.0004). Among women in both groups, the concentration of TX was high, while similar levels were observed in the group of men from the NDIP group. However, when comparing men in the DIP and NDIP groups, a lower TX level was noticeable in the DIP group.

CONCLUSIONS

A higher level of TX may be associated with a disturbance of the physiological phenomenon of DIP in men and women. However, in our opinion, TX is not the main determinant of the DIP phenomenon and, at the same time, other pro-inflammatory factors may also be involved in the occurrence of this singularity.

Clinical risk factors and predictive score for the non-dipper profile in hypertensive patients: a case-control study

Background

Night-time BP, especially non-dipper, is a stronger predictor of adverse cardiovascular outcomes. Ambulatory blood pressure monitoring (ABPM) is a gold standard for the detection of non-dippers but it often is unavailable and expensive. This study aims to determine clinical risk factors that predict non-dipper.

Methods

An exploratory traditional case-control study, exclusive sampling of control was conducted from January 2013 to September 2018 to explore clinical risk factors associated with non-dippers in hypertensive patients. Subgroup analysis was performed in each treated and untreated hypertensive patient. The parsimonious predictive score for non-dippers was constructed.

Results

The study included 208 hypertensive patients receiving 24 h ABPM. There were 104 dippers and 104 non-dippers. Significant clinical risk factors associated with non-dippers were the age of > 65 years, average office diastolic blood pressure (DBP), and fasting plasma glucose of > 5.6 mmol/L. Results of subgroup analysis showed that dyslipidemia, history of coronary artery disease, use of angiotensin-converting enzyme inhibitors (ACEIs) and direct vasodilators, average office DBP, and serum uric acid were associated with non-dippers in treated hypertensive patients, however, there were no risk factors associated with non-dippers in the untreated group. The predictive score for non-dippers in treated group included average office DBP, dyslipidemia, serum uric acid, male, calcium channel blockers and ACEIs use. The area under Receiver Operating Characteristic (AuROC) was 0.723. A cut-off point which was > 0.0701 and prevalence of non-dippers of 46%, this score had a sensitivity of 77.4%, specificity of 65.6%, positive predictive value (PPV) of 66.1%, and negative predictive value (NPV) of 79.6%. For untreated group, age, hemoglobin and body mass index were included in the predictive model. AuROC was 0.74. There was a sensitivity of 51.9%, specificity of 91.2%, PPV of 82.4%, and NPV of 70.5% at the cut-off point of > 0.357, and prevalence of 44%.

Conclusion

There were several significant clinical risk factors associated with non-dippers in treated hypertensive patients. The predictive score might be useful for the detection of non-dippers; however, it cannot replace ABPM.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40885-021-00180-4.

Clinical effectiveness and safety of amlodipine/losartan-based single-pill combination therapy in patients with hypertension: Findings from real-world, multicenter observational databases

Various single‐pill combinations (SPCs) have been introduced to improve drug compliance and clinical efficacy. However, there is a lack of real‐world evidence regarding the effectiveness of these SPCs for hypertension. This study evaluated the real‐world clinical efficacy and safety of amlodipine/losartan‐based SPC therapies in patients with hypertension in a real‐world setting. A total of 15 538 patients treated with amlodipine/losartan‐based SPCs [amlodipine + losartan (AL), amlodipine + losartan + rosuvastatin (ALR), and amlodipine + losartan + chlorthalidone (ALC)] were selected from the database of three tertiary hospitals in Korea. The efficacy endpoints were target blood pressure (BP) and low‐density lipoprotein cholesterol (LDL‐C) achievement rates. Safety was evaluated based on laboratory parameters. Drug adherence was defined as the proportion of medication days covered (PDC). The target BP attainment rate was above 90% and was similar among the three groups. Although many patients in the AL and ALC groups took statins, the target LDL‐C attainment rate was significantly higher in the ALR group than in the AL and ALC groups. Safety endpoints were not significantly different among the groups, except serum uric acid level and incidence rate of new‐onset hyperuricemia, which were significantly lower in the AL and ALR groups than in the ALC group. The PDC was > 90% in all groups. In the real‐world hypertensive patients, amlodipine/losartan‐based SPC therapy demonstrated good target BP achievement rates. Especially, rosuvastatin‐combination SPC showed better target LDL‐C goal achievement rate compared to the other SPCs. All three amlodipine/losartan‐based SPC had excellent drug adherence.

Variation in serum urate levels in the absence of gout and urate lowering therapy

BACKGROUND

Previous studies have noted significant variation in serum urate (sUA) levels, and it is unknown how this influences the accuracy of hyperuricemia classification based on single data points. Despite this known variability, hyperuricemic patients are often used as a control group in gout studies. Our objective was to determine the accuracy of hyperuricemia classifications based on single data points versus multiple data points given the degree of variability observed with serial measurements of sUA.

METHODS

Data was analyzed from a cross-over clinical trial of urate-lowering therapy in young adults without a gout diagnosis. In the control phase, sUA levels used for this analysis were collected at 2-4 week intervals. Mean coefficient of variation for sUA was determined, as were rates of conversion between normouricemia (sUA ≤6.8 mg/dL) and hyperuricemia (sUA > 6.8 mg/dL).

RESULTS

Mean study participant (n = 85) age was 27.8 ± 7.0 years, with 39% female participants and 41% African-American participants. Mean sUA coefficient of variation was 8.5% ± 4.9% (1 to 23%). There was no significant difference in variation between men and women, or between participants initially normouricemic and those who were initially hyperuricemic. Among those initially normouricemic (n = 72), 21% converted to hyperuricemia during at least one subsequent measurement. The subgroup with initial sUA < 6.0 (n = 54) was much less likely to have future values in the range of hyperuricemia compared to the group with screening sUA values between 6.0-6.8 (n = 18) (7% vs 39%, p = 0.0037). Of the participants initially hyperuricemic (n = 13), 46% were later normouricemic during at least one measurement.

CONCLUSION

Single sUA measurements were unreliable in hyperuricemia classification due to spontaneous variation. Knowing this, if a single measurement must be used in classification, it is worth noting that those with an sUA of < 6.0 mg/dL were less likely to demonstrate future hyperuricemic measurements and this could be considered a safer threshold to rule out intermittent hyperuricemia based on a single measurement point.

TRIAL REGISTRATION

Data from parent study ClinicalTrials.gov Identifier: NCT02038179 .

Association of hyperuricemia and hypertension phenotypes in hypertensive patients without uric acid lowering treatment

BACKGROUND

Current study was to evaluate the association of hypertensive and hypertension phenotypes in hypertensive populations.

METHODS

Patients with primary hypertension and without any uric acid (UA)-lowering treatment were enrolled. Baseline characteristics including office blood pressure (OBP), 24 h ambulatory blood pressure (ABP), and serum UA (SUA) were measured. According to SUA, patients were divided into normal SUA and hyperuricemia groups. Based on OBP and 24 h-ABP, hypertension phenotypes were classified as controlled hypertension (CH), white-coat uncontrolled hypertension (WCUH), masked uncontrolled hypertension (MUCH), and sustained uncontrolled hypertension (SUCH).

RESULTS

Compared to patients with normal SUA (n = 336), patients with hyperuricemia (n = 284) were older and more likely to be men, obese, physically inactive, and have a higher prevalence of diabetes. C-reactive protein (CRP) level was higher in patients with hyperuricemia. The prevalence of CH, WCUH, and MUCH was similar between these two groups. However, the prevalence of SUCH was higher in patients with hyperuricemia than patients with normal SUA. Linear regression analysis indicated that increased SUA was significantly associated with 24 h-systolic BP and daytime-systolic BP. Normal SUA was served as the reference group, and presence of hyperuricemia was associated with higher odds of SUCH (odds ratio 1.46 and 95% confidence interval 1.27-1.93) after adjusted for potential covariates including age, male gender, obesity, diabetes, CRP, and antihypertensive drugs.

CONCLUSION

In hypertensive patients without UA-lowering treatment, presence of hyperuricemia was associated with higher odds of SUCH. Future studies are needed to evaluate whether lowering SUA can help to improve 24 h-ABP control.

Association between Serum Uric Acid and Pre-hypertension and Hypertension among Chinese Adults

Fundamento

O ácido úrico (AU), produto final do metabolismo dos nucleotídeos das purinas, participa dos processos de doenças metabólicas e cardiovasculares. Evidências experimentais sugerem que o ácido úrico é um mediador importante na resposta fisiológica ao aumento da pressão arterial.

Objetivo

Avaliar a associação entre os níveis séricos de AU e pré-hipertensão e hipertensão em uma população chinesa.

Métodos

Conduziu-se um estudo transversal entre março e setembro de 2017, e 1.138 participantes com idades entre 35 e 75 anos foram incluídos neste estudo, onde 223 normotensos, 316 pré-hipertensos e 599 hipertensos foram selecionados para avaliar a associação entre níveis séricos de AU e hipertensão. Considerou-se um valor de p<0,05 estatisticamente significativo.

Resultados

Os níveis séricos de AU foram significativamente maiores no grupo pré-hipertensão e hipertensão em comparação com o grupo controle em toda a população (p<0,05 para todos). A análise quantitativa das características indicou níveis séricos de AU (2,92±0,81, 3,06±0,85, 3,22±0,98 mg/d) linearmente aumentados em mulheres normotensas, pré-hipertensas e hipertensas, com um valor de p de 0,008. Os níveis séricos de AU nos quartis correlacionaram-se positivamente com a PAD (p<0,05), principalmente em mulheres. Após o ajuste para idade, sexo, índice de massa corporal (IMC), glicose (GLI), colesterol total (CT), triglicerídeos (TG), colesterol HDL (lipoproteína de alta densidade), as razões de chances ( odds ratios — ORs) e intervalos de confiança (IC) de 95% da pré-hipertensão, dos níveis séricos de AU mais baixos (referentes) aos mais altos foram 1,718 (1,028–2,872), 1,018 (0,627–1,654) e 1,738 (1,003–3,010). Além disso, o segundo quartil dos níveis séricos de AU esteve significativamente associado à hipertensão, com uma OR (IC 95%) de 2,036 (1,256–3,298).

Conclusões

O presente estudo sugere que níveis séricos mais elevados de AU estão positivamente associados à pré-hipertensão e hipertensão entre adultos chineses.

The Role of Uric Acid in the Acute Myocardial Infarction: A Narrative Review

Increased serum uric acid (SUA) levels have been associated with various pathologic processes such as increased oxidative stress, inflammation, and endothelial dysfunction. Thus, it is not surprising that increased SUA is associated with various adverse outcomes including cardiovascular (CV) diseases. Recent epidemiological evidence suggests that increased SUA may be related to acute myocardial infarction (AMI). Accumulating data also showed that elevated UA has pathophysiological role in the development of AMI. However, there are also studies showing that SUA is not related to the risk of AMI. In this narrative review, we summarized the recent literature data regarding SUA and AMI after providing some background information for the association between UA and coronary artery disease. Future studies will show whether decreasing SUA levels is beneficial for outcomes related to AMI and the optimum SUA levels for best outcomes in CV diseases.

Comparison Between Automated Office Blood Pressure Measurements and Manual Office Blood Pressure Measurements-Implications in Individual Patients: a Systematic Review and Meta-analysis

PURPOSE OF REVIEW

Automated office blood pressure (AOBP) measurements may provide more accurate estimation of blood pressure (BP) than manual office blood pressure (MOBP) measurements. This systematic review investigated the diagnostic performance of AOBP and MOBP using ambulatory blood pressure measurement (ABPM) as reference. Several databases including MEDLINE, Embase, Scopus, and China Academic Journals were searched. Data were extracted, double-checked by two investigators, and were analysed using a random effects model.

RECENT FINDINGS

A total of 26 observational studies were included. The mean systolic/diastolic BP obtained by AOBP was not significantly different from that obtained by ABPM. The sensitivity and specificity of AOBP to detect elevated BP were approximately 70%. Fewer participants had white-coat hypertension on AOBP measurement than on MOBP measurement (7% versus 14%); however, about 13% had masked hypertension on AOBP measurement. The width of the limit of agreement comparing (i) AOBP and ABPM and (ii) MOBP and ABPM was comparable. AOBP may reduce the rate of the observed white-coat effect but undermine masked hypertension. The current recommendation, however, is limited by the absence of high-quality studies and the high heterogeneity of our results. More high-quality studies using different AOBP machines and in different population are therefore needed.

The association between serum uric acid and diabetic complications in patients with type 2 diabetes mellitus by gender: a cross-sectional study

BACKGROUND

The relationship between serum uric acid (SUA) and several diabetic complications or co-morbidities remains a matter of debate. The study aims to explore the association between SUA levels and the prevalence of non-alcoholic fatty liver disease (NAFLD), diabetic retinopathy (DR), diabetic nephropathy (DN) and diabetic peripheral neuropathy (DPN) in patients with type 2 diabetes mellitus (T2DM).

METHODS

A total of 2,809 participants (1,784 males and 1,025 females) were included in this cross-sectional study. Clinical characteristics and the prevalence of each of the four diseases were analyzed based on gender-specific quartiles of SUA levels. The Pearson correlation analysis and linear-regression analysis were used to access the correlation between SUA levels and clinical characteristics. Furthermore, a binary logistic regression analysis was carried out to determine whether SUA was an independent risk factor for each of the four complications.

RESULTS

SUA levels were positively correlated to BMI, BUN, Scr and TG, but negatively associated with eGFR, HDL, FBG, 2h-PG and HbA1c% for the patients with T2DM. The prevalence of NAFLD and DN, but not DR or DPN, were increased with SUA levels from the first to the fourth quartile. Binary logistic regression further disclosed that SUA was an independent risk factor for NAFLD (ORs Male = 1.002, ∗ P = 0.0013; ORs Female = 1.002, ∗ P = 0.015) and DN (ORs Male = 1.006, ∗ P < 0.001; ORs Female = 1.005, ∗ P < 0.001), but not for DR and DPN. After adjustment for the confounders, SUA levels were significantly associated with NAFLD within the 3rd (ORs = 1.829, P = 0.004) and 4th quartile (ORs = 2.064, P = 0.001) for women, but not independently associated with SUA for man. On the other hand, our results revealed increased prevalence of DN for SUA quartile 2 (ORs = 3.643, P = 0.039), quartile 3 (ORs = 3.967, P = 0.024) and quartile 4 (ORs = 9.133, P < 0.001) in men; however, SUA quartiles were significantly associated with DN only for quartile 4 (ORs = 4.083, P = 0.042) in women.

CONCLUSION

For patients with T2DM, elevated SUA concentration is an independent risk factor for the prevalence of NAFLD and DN after adjustment for other indicators, but not DR or DPN.

Uric Acid and Hypertension: An Update With Recommendations

The association between increased serum urate and hypertension has been a subject of intense controversy. Extracellular uric acid drives uric acid deposition in gout, kidney stones, and possibly vascular calcification. Mendelian randomization studies, however, indicate that serum urate is likely not the causal factor in hypertension although it does increase the risk for sudden cardiac death and diabetic vascular disease. Nevertheless, experimental evidence strongly suggests that an increase in intracellular urate is a key factor in the pathogenesis of primary hypertension. Pilot clinical trials show beneficial effect of lowering serum urate in hyperuricemic individuals who are young, hypertensive, and have preserved kidney function. Some evidence suggest that activation of the renin-angiotensin system (RAS) occurs in hyperuricemia and blocking the RAS may mimic the effects of xanthine oxidase inhibitors. A reduction in intracellular urate may be achieved by lowering serum urate concentration or by suppressing intracellular urate production with dietary measures that include reducing sugar, fructose, and salt intake. We suggest that these elements in the western diet may play a major role in the pathogenesis of primary hypertension. Studies are necessary to better define the interrelation between uric acid concentrations inside and outside the cell. In addition, large-scale clinical trials are needed to determine if extracellular and intracellular urate reduction can provide benefit hypertension and cardiometabolic disease.

The interaction between serum uric acid and triglycerides level on blood pressure in middle-aged and elderly individuals in China: result from a large national cohort study

Background

The purpose of the research was to explore the extent of interaction between triglycerides (TG) and serum uric acid (SUA) level with blood pressure (BP) in middle-aged and elderly individuals in China.

Methods

Data were selected from the China Health and Retirement Longitudinal Study (CHARLS), a cross-sectional study. 3345(46.99%) men with average ages of 60.24 ± 9.24 years and 3774 (53.01%) women with average ages of 59.91 ± 9.95 years were included in the study. Differences between gender, or between categories of blood pressure levels were evaluated by t-test or chi-square test. The adjusted associations between various characteristics and BP status were first compared using linear regression models, as appropriate. Then, A general linear model adjusted for confounding factors (socio-demographic characteristics [age, educational levels, marital status, place of residence], health behaviors [cigarette smoking, alcohol drinking, eating habits, social and leisure activities, accidental injury, physical activities], medical history [history of cardiovascular diseases, hepatitis history, antidiabetic drugs, history of antilipidemic medication, anti-hypertensive therapy], metabolic measures [C-reactive protein (CRP), hemoglobin A1c (HbA1c), fasting plasma glucose (FPG), low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), estimated glomerular filtration rate (eGFR), body mass index (BMI)]) was used to examine the synergistic effect of SUA and TG level on BP in middle-aged and elderly individuals in China.

Results

Age-adjusted partial Pearson’s correlation coefficient showed that SUA and TG level positively correlated with both systolic blood pressure (SBP) and diastolic blood pressure (DBP) in both men and women. Multiple linear regression analysis showed the TG level was significantly and positively associated with SBP and DBP in both men (SBP: β =0.068, P = 0.001; DBP: β =0.064, P = 0.002) and women (SBP: β =0.061, P = 0.002; DBP: β =0.084, P = 0.000), but SUA were significantly and positively associated with SBP in both men (SBP: β =0.047, P = 0.013) and women (SBP: β =0.040, P = 0.028), regardless of other confounding factors. After adjusting for related potential confounders, evidence of interaction between SUA and TG level on SBP (men: β = − 1.090, P = 0.726; women: β = − 0.692, P = 0.861) and DBP (men: β = − 1.026, P = 0.572; women: β = − 0.794, P = 0.842) was not observed.

Conclusion

The interaction effect of SUA and TG level on BP was not observed in our study. Moreover, high SUA level was significantly associated with SBP, while high TG level was strongly related to both DBP and SBP.

Body mass index and serum uric acid level: Individual and combined effects on blood pressure in middle-aged and older individuals in China

Few studies on the individual and combined analysis between serum uric acid (SUA) and body mass index (BMI) and blood pressure (BP) were conducted in individuals aged ≥45 years. We aimed to assess the extent to which BMI and SUA and their interaction affect BP in Chinese middle-aged and older adults.Data were selected from the China Health and Retirement Longitudinal Study (CHARLS). A total of 5888 individuals aged 45 to 96 was included. Differences between BMI, or between categories of blood pressure were evaluated by t test or chi-square test. The trend of related variables according to four BMI categories was also tested using contrast analysis. The adjusted associations between various characteristics and BP status were first compared using linear regression models, as appropriate. Then, general linear models adjusting for related potential confounders were used to examine the synergistic effect of SUA and BMI level on BP for middle-aged and elderly individuals in China.Age-adjusted partial Pearson correlation coefficient showed that BMI was significantly and positively correlated with BP both in male and female, SUA positively correlated with both systolic blood pressure (SBP) and diastolic blood pressure (DBP) in males with BMI <24.0 kg/m and females with BMI <24.0 kg/m. However, SUA level significantly and positively correlated with DBP, but not with SBP, in females with BMI ≥24.0 kg/m. Multiple linear regression analysis showed that BMI was independently associated with BP both in male and female, SUA significantly and positively associated with SBP in both males and females with BMI <24.0 kg/m, However, SUA level positively correlated with DBP in females with BMI <24.0 kg/m, but not with males with BMI <24.0 kg/m, independent of other confounding factors. A general linear model analysis adjusted for confounding factors did not reveal interaction between BMI, SUA levels and SBP (β=-1.404, P = .686 in males; β=-2.583, P = .575 in females) and DBP (β=-2.544, P = .263 in males; β=-2.619, P = .622 in females).No interaction between BMI, SUA levels, and BP was observed in either males or females; However, BMI was independently associated with BP both in male and female, SUA independently associated with SBP both in males and females with BMI <24.0 kg/m, and SUA independently associated with DBP in females with BMI ≥24.0 kg/m.

Hyperuricemia and Hypertension: Links and Risks

Hyperuricemia has long been recognized to be associated with increased cardiovascular risk, including risk of developing hypertension. Epidemiological findings suggest that the link with hypertension is stronger in children and adolescents. Uric acid acts as a strong antioxidant compound in the extracellular environment but has pro-inflammatory effects within the intracellular setting. A chronic phase of microvascular injury is known to occur after prolonged periods of hyperuricemia. This is proposed to contribute to afferent arteriolopathy and elevation of blood pressure that may become unresponsive to uric acid-lowering therapies over time. Studies have struggled to infer direct causality of hyperuricemia due to a vast number of confounders including body mass index. The aim of this review is to present the available data and highlight the need for large scale prospective randomized controlled trials in this area. At present, there is limited evidence to support a role for uric acid-lowering therapies in helping mitigate the risk of hypertension.

Associations between neutrophil/lymphocyte ratio, platelet/lymphocyte ratio, albuminuria and uric acid and the estimated glomerular filtration rate in hypertensive patients with chronic kidney disease stages 1-3

INTRODUCTION

The neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR), albuminuria and uric acid are known to be independent predictors of hypertension and cardiovascular mortality. However, to date, no study has been conducted describing the relationships between the NLR, PLR and estimated glomerular filtration rate (eGFR) in hypertensive patients with chronic kidney disease (CKD) who do not require renal replacement therapy.

MATERIAL AND METHODS

This prospective study included 271 patients with essential hypertension and eGFR ≥ 30 ml/min/1.73 m². The patients were divided into two groups: those with CKD stages 1 and 2 and those with stage 3. We used the complete blood count to calculate the NLR and PLR, and we measured the albuminuria and uric acid levels. Then, we studied their associations with the eGFR and their potential uses as independent risk factors for renal damage.

RESULTS

The NLR, albuminuria and uric acid were higher in patients with CKD stage 3 than in those with stages 1 and 2 (p = 0.013, p = 0.001 and p = 0.001, respectively). However, no significant difference was detected in the PLR. In stage 3 patients, albuminuria and uric acid were found to be independent risk factors affecting the eGFR (p = 0.042 and p = 0.001, respectively). However, the effects of the NLR and PLR on the eGFR were not significant (p = 0.104 and p = 0.578, respectively).

CONCLUSIONS

The NLR, similar to albuminuria and uric acid, the NLR was found to be a specific marker for CKD stage 3 patients. However, the NLR and PLR did not act as independent risk factors affecting the eGFR.

Elevated Serum Uric Acid Is Associated With Greater Risk for Hypertension and Diabetic Kidney Diseases in Obese Adolescents With Type 2 Diabetes: An Observational Analysis From the Treatment Options for Type 2 Diabetes in Adolescents and Youth (TODAY) Study

OBJECTIVE

Elevated serum uric acid (SUA) is increasingly recognized as a risk factor for kidney disease in adults with diabetes, but data in youth are limited. We hypothesized that elevated SUA predicts development of elevated urinary albumin excretion (UAE) and hypertension over time in teens with type 2 diabetes (T2D).

RESEARCH DESIGN AND METHODS

Serum creatinine, cystatin C, SUA, and the urine albumin-to-creatinine ratio (UACR) were assessed in 539 obese youth, ages 12-17 years, with T2D duration <2 years at baseline in the Treatment Options for Type 2 Diabetes in Adolescents and Youth (TODAY) study. Estimated glomerular filtration rate (eGFR) was calculated using creatinine and cystatin C. Hypertension was defined as systolic or diastolic blood pressure ≥130/80 mmHg and elevated UAE as UACR ≥30 mg/g. Cox proportional hazards models evaluated the relationship between SUA and outcome variables longitudinally over an average follow-up of 5.7 years, adjusting for age, sex, race/ethnicity, BMI, HbA_1c, eGFR, ACE inhibitor/angiotensin receptor blocker use, and TODAY treatment group assignment.

RESULTS

At baseline, hyperuricemia (≥6.8 mg/dL) was present in 25.6% of participants, hypertension in 18.7%, and elevated UAE in 6.1%. During follow-up of up to 7 years, hypertension developed in 37.4% and UAE in 18.0%. Higher baseline SUA increased the risk of incident hypertension (hazard ratio [HR] 1.19, 95% CI 1.03-1.38, per 1 mg/dL increase in SUA) and elevated UAE (HR 1.24, 95% CI 1.03-1.48) in adjusted models.

CONCLUSIONS

Hyperuricemia was common in youth with T2D. Higher baseline SUA independently increased the risk for onset of hypertension and elevated UAE. Research is needed to determine whether SUA-lowering therapies can impede development of diabetic kidney disease and hypertension in T2D youth.

Trends of Lipophilic, Antioxidant and Hematological Parameters Associated with Conventional and Electronic Smoking Habits in Middle-Age Romanians

It is known that cigarette smoking is correlated with medical associated inquires. New electronic cigarettes are intensively advertised as an alternative to conventional smoking, but only a few studies demonstrate their harmful potential. A cross-sectional study was designed using 150 subjects from Brasov (Romania), divided into three groups: non-smokers (NS = 58), conventional cigarettes smokers (CS = 58) and electronic cigarettes users (ECS = 34). The aim of this study was to determine levels of some plasma lipophilic and hematological components, and the total antioxidant status that could be associated with the smoking status of the subjects. Serum low density lipoproteins (LDL) cholesterol increased significantly for ECS participants versus NS group (18.9% difference) (p < 0.05). Also, the CS group is characterized by an increase of serum LDL cholesterol (7.9% difference vs. NS), but with no significant statistical difference. The variation of median values of serum very low density lipoproteins (VLDL) was in order NS < ECS < CS, with statistical difference between NS and CS groups (34.6% difference; p = 0.023). When comparing the antioxidant status of the three groups, significant differences (p < 0.05) were obtained between NS vs. CS and NS vs. ECS. Similar behavior was identified for CS and ECS. Statistically significant changes (p < 0.0001) for both vitamin A and vitamin E were identified in the blood of NS vs. CS and NS vs. ECS, and also when comparing vitamin A in the blood of the CS group versus the ECS group (p < 0.05). When all groups were compared, the difference in the white blood cell (WBC) was (p = 0.008). A slight increase in the red blood cell (RBC) count was observed, but with no statistical difference between groups. These results indicated that conventional cigarette and e-cigarette usage promotes the production of excess reactive oxygen species, involving different pathways, different antioxidants and bioactive molecules.

Association between platelet distribution width and serum uric acid in Chinese population

Platelet distribution width (PDW) is a simple and inexpensive parameter, which could predict activation of coagulation efficiently. And it has been confirmed to have a significant role in many diseases. We aimed to explore the association between PDW and hyperuricemia in a large Chinese cohort. This cross-sectional study recruited 61,091 ostensible healthy participants (29,259 males and 31,832 females) after implementing exclusion criteria. Clinical data of the enrolled population included anthropometric measurements and serum parameters. Database was sorted by gender, and the association between PDW and hyperuricemia was analyzed after dividing PDW into quartiles. Crude and adjusted odds ratios of PDW for hyperuricemia with 95% confidence intervals were analyzed using binary logistic regression models. We found no significant difference in PDW values between the genders. Males showed significantly higher incidence of hyperuricemia than females. From binary logistic regression models, significant hyperuricemia risks only were demonstrated in PDW quartiles 2 and 3 in males (P < 0.05). This study displayed close association between PDW and hyperuricemia as a risk factor. It is meaningful to use PDW as a clinical risk predictor for hyperuricemia in males. © 2019 BioFactors, 45(3):326-334, 2019.

Complete blood count-derived inflammatory markers in adolescents with primary arterial hypertension: a preliminary report

Aim of the study

The aim of our study was to evaluate selected inflammatory markers in children with untreated primary hypertension and to establish the relation between inflammatory markers and 24-hour ambulatory blood pressure monitoring (ABPM) and clinical and biochemical parameters.

Material and methods

In 54 children (15.12 ±2.02 years) with untreated primary hypertension, with excluded overt inflammation, we evaluated: neutrophils (NEU; 1000/μl), lymphocytes (LYM; 1000/μl), platelets (PLT; 1000/μl), mean platelet volume (MPV; fl), neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), ABPM (OSCAR 2 SUNTECH), and selected clinical and biochemical parameters. The control group consisted of 20 healthy children (15.55 ±2.27 years).

Results

Children with primary hypertension had (p < 0.01) higher 24-hour systolic, diastolic and mean blood pressure, systolic and diastolic blood pressure loads, and pulse pressure. Hypertensive children did not differ in inflammatory indicators (NEU, LYM, PLT, MPV, NLR, PLR) from the control group. In 54 hypertensive children we found the following correlations: between office systolic and diastolic blood pressure and MPV (r = 0.35, p = 0.011, r = 0.36, p = 0.008), between 24-hour ambulatory mean arterial pressure Z-score and NLR (r = 0.30, p = 0.030), 24-hour systolic blood pressure load and NLR (r = 0.38, p = 0.005), plasma renin activity and neutrophil count, NLR, PLR (r = 0.47, p = 0.016, r = 0.64, p < 0.001, r = 0.42, p = 0.033), urinary albumin loss and neutrophil count, NLR (r = 0.46, p = 0.001 and r = 0.42, p = 0.003). Multivariate analysis revealed that office SBP Z-score was related to MPV (β = 0.35, p = 0.008) and albuminuria to neutrophil count (β = 0.62, p = 0.018).

Conclusions

In children with primary arterial hypertension there may be a relation between blood pressure, urinary albumin loss, and subclinical inflammation.

Atherogenic Index in Type 2 Diabetes and Its Relationship with Chronic Microvascular Complications

OBJECTIVE

This study was designed to investigate risk factors related to atherogenic index of plasma (AIP), as well as the relationship between AIP and chronic microvascular complications in patients with type 2 diabetes (T2DM).

METHODS

This study included 2523 patients with T2DM who had not been treated with lipid-lowering drugs and were admitted to the Department of Endocrinology at Zhongnan Hospital, Wuhan University, during the period from January 2015 to February 2018. Anthropometric indicators were measured after overnight fasting. Low-density lipoprotein cholesterol (LDL-C), high-density lipoprotein cholesterol (HDL-C), total cholesterol (TC), and triglyceride (TG) were detected by enzymatic analysis. Standard 75 g oral glucose tolerance testing was performed to measure 0 and 2 hr plasma levels of glucose and insulin. Insulin sensitivity was assessed with HOMA-IR.

RESULTS

Increase in AIP was associated with an increased risk for hypertension (P < 0.05), HbA_1c (P < 0.05), HOMA-IR (P < 0.05), UA (P < 0.05), and decreased eGFR levels (P < 0.05). Furthermore, AIP values directly correlated with BMI (r = 0.182, P < 0.001), waist circumference (r = 0.129, P < 0.001), blood glucose index (FBG (r = 0.153, P < 0.001), PPBG (r = 0.117, P < 0.001), and HbA_1c (r = 0.074, P < 0.001)), insulin resistance (HOMA-IR; r = 0.112, P < 0.001), and uric acid (UA, r = 0.177, P < 0.001). Multiple logistic regression analysis showed that waist circumference, HOMA-IR, FBG, systolic blood pressure, and UA were independent risk factors for AIP (all P < 0.05). The prevalence of diabetic neuropathy and metabolic syndrome was significantly higher among patients with higher AIP.

CONCLUSION

AIP represents a clinically convenient indicator for the detection of T2DM with high risk of complications and associated diseases and thus is a good predictor and indicator for follow-up monitoring in the treatment of patients with high-risk type 2 diabetes.

Higher Frequency of Nocturnal Blood Pressure Dipping but Not Heart Rate Dipping in Inflammatory Bowel Disease

BACKGROUND

Masked hypertension (MHTN) and lack of nocturnal dipping in blood pressure (BP) have been linked to the state of inflammation.

AIMS

We aimed to assess the frequency of nocturnal patterns of BP and heart rate (HR) in patients with IBD.

METHODS

Sixty-three normotensive patients with confirmed IBD during remission and 63 healthy subjects were enrolled in a case-control study. All subjects were monitored for BP and HR over a period of 24 h under ambulatory setting. Means for BP and HR were calculated for nighttime and daytime periods. Daytime BP ≥ 135/85 mmHg, nighttime BP ≥ 120/70 mmHg, and 24-h average BP ≥ 130/80 mmHg were defined as MHTN. The main end points of this study were lack of >10% nocturnal decrease in the systolic BP (NDP-BP) and in HR (NDP-HR).

RESULTS

After exclusion of 8 patients with IBD from analysis, 55 patients and 63 control subjects (49% men) with a mean age of 37.5 ± 11.0 years were enrolled. NDP-BP was more common in the IBD group compared to controls (55 vs. 33%; P = 0.026). MHTN was detected in 24% of IBD patients compared to 8% among controls (P = 0.017). Meanwhile, NDP-HR was observed in 22% of the IBD patients and 30% of the control group (P = 0.402). IBD remained a significant predictor of NDP-BP (odds ratio 2.60, 95% confidence interval 1.19-5.51) following an adjustment for age and gender.

CONCLUSIONS

IBD is associated with higher frequency of NDP-BP and MHTN; however, nocturnal changes in HR were similar in both groups.

Asymptomatic hyperuricemia is independently associated with coronary artery calcification in the absence of overt coronary artery disease: A single-center cross-sectional study

Recently, the pathogenic role of uric acid (UA) in both systemic metabolic and atherosclerotic diseases has been investigated. We sought to determine the independent correlation between serum UA levels and coronary artery calcification, as a marker of subclinical atherosclerosis. A total of 4188 individuals without prior coronary artery disease or urate-deposition disease were included. All of the participants underwent multidetector computed tomography (MDCT) for the evaluation of coronary artery calcification (CAC) during their health check-ups. The subjects were divided into thre groups according to CAC scores (group 1: 0; group 2: 1-299; group 3: ≥300). After controlling for other confounders, serum UA levels were found to be positively associated with increasing CAC scores (P = 0.001). Adjusted mean serum UA levels in each CAC group were estimated to be 5.2 ± 0.1 mg/dL, 5.3 ± 0.1 mg/dL, and 5.6 ± 0.2 mg/dL from groups 1, 2, and 3, respectively. Subsequent subgroup analyses revealed that this positive association was only significant in participants who were male, relatively older, less overweight, and did not have diabetes mellitus (DM), hypertension, smoking history, or renal dysfunction. In conclusion, serum uric acid levels were independently associated with CAC score severity and this finding is particularly relevant to the subjects who were male, relatively older, less overweight (body mass index < 25 kg/m), and without a history of DM, hypertension, smoking, or renal dysfunction.

Effect of plasma NOx values on cardiac function in obese hypertensive and normotensive pediatric patients

BACKGROUND

Hypertension (HT) is a major comorbidity of obesity that is associated with an increased risk of cardiovascular disease and higher mortality. The aim of our study was to evaluate cardiac function in obese hypertensive (OHT) and obese normotensive (ONT) pediatric patients and determine the effects of plasma nitric oxide (NOx) values on cardiac function, while demonstrating the role of plasma NOx in HT in obese pediatric patients.

METHODS

The study population consisted of 62 patients (27 boys, 35 girls), aged 13-18 years and 21 age-matched healthy controls. All subjects enrolled in the study underwent echocardiography (Echo) evaluation and ambulatory blood pressure monitoring for HT. Plasma NOx and biochemical values were studied in both patient groups separately.

RESULTS

Plasma NOx levels were found to be lower in the OHT group than in the ONT and control groups (p < 0.001) and to be negatively correlated with left ventricular mass index values (p < 0.05). Both the OHT and ONT groups had concentric hypertrophy of the heart.

CONCLUSIONS

Plasma NOx plays an essential role in obesity-induced HT. Concentric hypertrophy of the left ventricle was found in both the OHT and ONT groups, indicating structural deformation of the heart.

Comparative transcriptional profiling of renal cortex in rats with inherited stress-induced arterial hypertension and normotensive Wistar Albino Glaxo rats

Background

The renal function plays a leading role in long-term control of arterial pressure. The comparative analysis of renal cortex transcriptome in ISIAH rats with inherited stress-induced arterial hypertension and normotensive WAG rats was performed using RNA-Seq approach. The goal of the study was to identify the differentially expressed genes (DEGs) related to hypertension and to detect the pathways contributing to the differences in renal functions in ISIAH and WAG rats.

Results

The analysis revealed 716 genes differentially expressed in renal cortex of ISIAH and WAG rats, 42 of them were associated with arterial hypertension and regulation of blood pressure (BP). Several Gene Ontology (GO) terms significantly enriched with DEGs suggested the existence of the hormone dependent interstrain differences in renal cortex function. Multiple DEGs were associated with regulation of blood pressure and blood circulation, with the response to stress (including oxidative stress, hypoxia, and fluid shear stress) and its regulation. Several other processes which may contribute to hypertension development in ISIAH rats were: ion transport, regulation of calcium ion transport, homeostatic process, tissue remodeling, immune system process and regulation of immune response.

KEGG analysis marked out several pathways significantly enriched with DEGs related to immune system function, to steroid hormone biosynthesis, tryptophan, glutathione, nitrogen, and drug metabolism.

Conclusions

The results of the study provide a basis for identification of potential biomarkers of stress-sensitive hypertension and for further investigation of the mechanisms that affect renal cortex function and hypertension development.

Electronic supplementary material

The online version of this article (doi:10.1186/s12863-015-0306-9) contains supplementary material, which is available to authorized users.

Association of Serum Uric Acid Level With Blood Pressure Variability in Newly Diagnosed Essential Hypertension

Serum uric acid (UA) is independently associated with hypertension and blood pressure (BP) variability (BPV) is associated with cardiovascular events and mortality in hypertensive patients. The aim of the present study was to assess the association of serum UA with BPV in 300 untreated essential hypertension patients (mean age 57.3±13.6 years). BPV was quantified as the standard deviation (SD) of the 24-hour, daytime, and nighttime mean values obtained by using ambulatory BP monitoring. In correlation analysis, log UA values were found to be positively correlated with 24-hour systolic BPV and nighttime systolic and diastolic BPV (Pearson coefficients of 0.246, 0.280, and 0.353, respectively; P<.001 for all). In multivariate analysis, log UA had an independent association with 24-hour systolic BPV and nighttime systolic and diastolic BPV. This study show for the first time that increased serum UA is independently associated with BPV in untreated essential hypertension patients.

Hyperuricaemia is associated with renal damage independently of hypertension and intrarenal renin-angiotensin system activation, as well as their circadian rhythms

AIM

Both hyperuricaemia and activation of the intrarenal renin-angiotensin system (RAS) play an important role in the development of hypertension and renal damage. However, it has not been clear whether hyperuricaemia is associated with renal damage due to hypertension or intrarenal RAS activation, as well as their circadian rhythms.

METHODS

We recruited 43 chronic kidney disease (CKD) patients who did not receive RAS blockers and antihyperuricaemic drugs, and investigated the relationship among serum uric acid (sUA) levels, the circadian rhythm of urinary angiotensinogen (U-AGT) excretion levels, and the levels of albuminuria (U-ACR) and proteinuria (U-P/Cr).

RESULTS

sUA levels were significantly associated with estimated glomerular filtration rate (eGFR) (P = 0.002), systolic blood pressure (SBP) (daytime, P = 0.031), and U-ACR (daytime, P = 0.006 and nighttime, P = 0.008) and U-P/Cr (daytime, P = 0.017 and nighttime, P = 0.013). However, there were no significant differences between sUA levels and SBP in nighttime and U-AGT excretion levels in both time periods. Multiple regression analyses for sUA levels were performed using age, sex, eGFR and each parameter (SBP, U-AGT/Cr, U-ACR or U-P/Cr). sUA levels were not associated with SBP or U-AGT/Cr in both time periods. sUA levels tended to correlate with U-P/Cr levels in nighttime, and were significantly associated with U-P/Cr in daytime (P = 0.026) and U-ACR in daytime (P = 0.017) and nighttime (P = 0.046). Moreover, no significant differences were found between sUA levels and night-to-day ratios of some parameters.

CONCLUSION

These data suggest that hyperuricaemia is associated with renal damage, independently of hypertension and intrarenal RAS activation, as well as their circadian rhythms.

Improving the detection of preclinical organ damage in newly diagnosed hypertension: nocturnal hypertension versus non-dipping pattern

The clinical relevance of nocturnal hypertension (NH) in comparison with non-dipping status has not been clarified yet, as regards subclinical target organ damage. We aimed to elucidate whether NH or dipping status reflects better organ damage. The study population included 319 newly diagnosed hypertensive patients. Subclinical organ damage was evaluated to all participants. On the basis of nocturnal blood pressure (BP) levels the population was divided into two groups: NH and nocturnal normotension. Also, individuals were defined as dippers and non-dippers according to systolic BP fall. Patients with NH were characterized by increased arterial pulse wave velocity (PWV; 9.1±1.7 vs 8.4±1.5 m s(-1), P=0.0001) and carotid intima-media thickness (0.77±0.18 vs 0.69±0.15 mm, P=0.016) compared with normotensive subjects. Notably, they also exhibited higher values of left ventricular mass index (88.1±22.9 vs 82.8±16.6 g m(-)(2) P=0.043). On the contrary, non-dipping status was associated only with differences in PWV (9.26±0.2 vs 8.64±0.2 m s(-1), P=0.031, 8) and in creatinine clearance (95±3 vs 106±4, P=0.025) in the group of NH. The presence of NH is accompanied by subclinical atherosclerosis, as well as structural abnormalities of the left ventricle. Therefore, NH rather than non-dipping status could be preferably integrated with the risk of organ damage.

A pilot study on the impact of a low fructose diet and allopurinol on clinic blood pressure among overweight and prehypertensive subjects: a randomized placebo controlled trial

Fructose and sodium intake have been associated with hypertension and metabolic syndrome. Although various mechanisms are involved, fructose causes hypertension partly through rising intracellular and serum uric acid. To date, there are no studies in adults that have evaluated the impact of low fructose diets and allopurinol on prehypertensive and overweight subjects. The objective of this study was to compare the effect of low fructose diet and allopurinol or placebo on blood pressure (BP) and metabolic syndrome components The study was a controlled clinical trial and consisted of two phases; in the first phase of intervention (4 weeks), patients were randomized to either low fructose diet (34 patients) or control diet (38 patients). In the second phase of intervention (weeks 4-8), the same groups continued with the same diet prescriptions but were further randomized to receive placebo or allopurinol (300 mg/d). Clinic and 24-hour ambulatory BP, anthropometric measures, and laboratory data were determined at baseline, weeks 4 and 8. Seventy-two patients were included in the trial. At the end of the dietary phase, both diet groups significantly reduced their BP, but there were no between-group differences. Compared to placebo, at the end of follow-up, subjects in the allopurinol group had a lower clinic systolic blood pressure and this was significant within- and between-group comparisons. The percentage of dippers was higher in the allopurinol group, and weight was reduced significantly despite the absence of caloric restriction Allopurinol was associated with a significant reduction in clinic BP, an increase in the percentage of dippers, and significant weight loss. Larger studies with longer follow-up are needed to confirm our findings.

Serum Uric Acid, Alanine Aminotransferase, Hemoglobin and Red Blood Cell Count Levels in Pseudoexfoliation Syndrome

Purpose. The pathogenesis of pseudoexfoliation (PEX), the most common cause of secondary glaucoma, has not been clearly identified, but there is increasing evidence that points out the role of oxidative stress. The aim of this study is to evaluate some of the most commonly used blood parameters, hemoglobin (Hb), red blood cell count (RBC), alanine aminotransferase (ALT), and uric acid (UA) levels, in subjects with PEX. Materials and Methods. This study is performed in a state hospital between November 2011 and December 2012. Retrospective chart review of subjects who underwent cataract surgery was performed. Thirty-one healthy subjects with PEX and 34 healthy subjects without PEX were evaluated. Hb, RBC, ALT, and UA levels were recorded. Student's t-test was used to compare the two groups. Results. The mean age was 73.6 ± 14.1 years in PEX group and 70.1 ± 12.7 in control group (p = 0.293). Hb, RBC, ALT, and UA levels did not show a statistically significant difference among PEX and control groups (p > 0.05 for all). Conclusion. Serum levels of Hb, RBC, ALT, and UA levels were similar in subjects with and without PEX. Further studies are needed to clarify the precise role of Hb, RBC, ALT, and UA in the pathogenesis of PEX.

Uric Acid as a Marker of Kidney Disease: Review of the Current Literature

Uric acid has been implicated in the pathophysiology of renal disease; however renal clearance makes a causal relationship difficult to prove. We examine the current literature to support a potential role of uric acid in the development of kidney disease and to determine the potential to use uric acid as a marker for future renal decline. After review, we conclude that uric acid is definitively linked to the development of chronic kidney disease and can be a poor prognostic factor for the development of acute renal failure, as well. However, further human research is needed before predictive models utilizing uric acid can be developed and used in the clinical setting.

Serum uric acid and the risk of hypertension and chronic kidney disease

PURPOSE OF REVIEW

To discuss the evolving data regarding uric acid as a potential cause of hypertension and progressive renal dysfunction and its clinical and research implications.

RECENT FINDINGS

The potential mechanisms by which uric acid could cause vasoconstriction and a progressive ateriolopathy were established in animal models between 1999 and 2004. Since then, there has been a growing interest in the topic and numerous retrospective and prospective observational studies. The preponderance of data support the hypothesis that serum uric acid is a cause or exacerbating factor of hypertension and progressive kidney disease. Over the last couple of years clinical intervention trials, including randomized controlled trials in the young have supported this mechanistic role.

SUMMARY

Current evidence supports the role of uric acid as marker and mediator of risk for both hypertension and progressive decline in renal function. Data on the impact of xanthine oxidase inhibitors or uricosurics on clinical hypertension and chronic kidney disease are suggestive but inconclusive. Considerably, more data will be required to determine if uric acid lowering therapy will become a mainstay of management in diseases other than gout and tumor lysis syndrome.