Serum Uric Acid, Gender, and Low Ankle Brachial Index in Adults With High Cardiovascular Risk

Gender Influence on XOR Activities and Related Pathologies: A Narrative Review

Taking into account the patient's gender is the first step towards more precise and egalitarian medicine. The gender-related divergences observed in purine catabolism and their pathological consequences are good examples of gender medicine differences. Uric acid is produced by the activity of xanthine oxidoreductase (XOR). The serum levels of both XOR activity and uric acid differ physiologically between the genders, being higher in men than in women. Their higher levels have been associated with gout and hypertension, as well as with vascular, cardiac, renal, and metabolic diseases. The present review analyzes the gender-related differences in these pathological conditions in relation to increases in the serum levels of XOR and/or uric acid and the opportunity for gender-driven pharmacological treatment.

Risk factors for peripheral artery disease and diabetic peripheral neuropathy among patients with type 2 diabetes

AIMS

To investigate the prevalence of peripheral artery disease (PAD) and diabetic peripheral neuropathy (DPN) and the associated risk factors among Chinese patients with type 2 diabetes mellitus.

METHODS

A cross-sectional study was conducted using data between November 1, 2018, and December 31, 2022. PAD was defined as ABI ≤ 0.9. DPN diagnosis involved specialized physician assessments using questionnaires and vibration perception threshold tests. Logistic regression analysis was used to identify related factors. We also evaluated the association between the clustering of risk factors and disease incidence.

RESULTS

The study population comprised 13,315 patients (mean age: 63.3 years). 4.9 % of the patients had PAD and 43.9 % had DPN. Multivariate regression analysis revealed advanced age, smoking, hypertension, coronary heart disease, dyslipidemia, elevated HbA1c, and uric acid levels as independent risk factors for PAD. For DPN, independent risk factors included advanced age, female gender, hypertension, coronary heart disease, elevated total cholesterol, triglycerides, lipoprotein(a), fasting plasma glucose, HbA1c, alkaline phosphatase, cystatin C, albumin-to-creatinine ratio, and elevated homocysteine levels, whereas apolipoprotein A was a protective factor. The clustering of risk factors was prevalent and associated with higher disease risk.

CONCLUSIONS

Our study contributed to identifying high-risk individuals and improving lower limb health among diabetic individuals.

Hyperuricemia Is Associated with Left Ventricular Dysfunction and Inappropriate Left Ventricular Mass in Chronic Kidney Disease

Background. Hyperuricemia is common in patients with chronic kidney disease (CKD), and this may lead to poor cardiovascular (CV) outcomes. The aim of this cross-sectional study was to assess associations among serum uric acid (UA) and echocardiographic parameters, ankle-brachial index (ABI), and brachial-ankle pulse wave velocity (baPWV) in patients with CKD. Methods. A total of 418 patients with CKD were included. The echocardiographic measurements included left atrial diameter (LAD), left ventricular ejection fraction (LVEF) and the ratio of observed to predict left ventricular mass (LVM). ABI, baPWV and medical records were obtained. Results. Multivariable forward logistic regression analysis showed that a high UA level was significantly associated with LAD > 47 mm (odds ratio [OR], 1.329; p = 0.002), observed/predicted LVM > 128% (OR, 1.198; p = 0.008) and LVEF < 50% (OR, 1.316; p = 0.002). No significant associations were found between UA and ABI < 0.9 or baPWV > 1822 cm/s. Multivariate stepwise linear regression analysis showed that a high UA level correlated with high LAD (unstandardized coefficient β, 0.767; p < 0.001), high observed/predicted LVM (unstandardized coefficient β, 4.791; p < 0.001) and low LVEF (unstandardized coefficient β, −1.126; p = 0.001). No significant associations between UA and low ABI and high baPWV were found. Conclusion. A high serum UA level was associated with a high LAD, high observed/predicted LVM and low LVEF in the patients with CKD. A high serum UA level may be correlated with abnormal echocardiographic parameters in patients with stage 3–5 CKD.

Association of overweight and obesity with cardiovascular risk factors in patients with atherosclerotic diseases

Background

The aim of this study was to compare demographic, clinical and biochemical characteristics, including inflammatory markers, according to the nutritional status of patients with verified atherosclerotic disease.

Methods

This cross-sectional study involved 1045 consecutive patients with verified carotid disease or peripheral arterial disease (PAD). Anthropometric parameters and data on cardiovascular risk factors and therapy for hypertension and hyperlipidemia were collected for all participants.

Results

Carotid disease was positively and PAD was negatively associated with body mass index (BMI). Negative association between obesity and PAD was significant only in former smokers, not in current smokers or in patients who never smoked. Overweight and general obesity were significantly related to metabolic syndrome (p < 0.001), lower values of high - density lipoprotein cholesterol (p < 0.001), increased triglycerides (p < 0.001), hyperglycemia (p < 0.001), self-reported diabetes (p < 0.001), hypertension (p < 0.001), high serum uric acid (p < 0.001), increased high sensitivity C-reactive protein (p = 0.020) and former smoking (p = 0.005) after adjustment for age, gender and type of disease. Antihypertensive therapy seems to be less effective in patients who are overweight and obese.

Conclusions

In conclusion, overweight and general obesity were significantly related to several cardiovascular risk factors.

The Relationships of the Fractional Excretion of Uric Acid with Brachial-Ankle Pulse Wave Velocity and Ankle Brachial Index in Chinese Young Adults

BACKGROUND/AIMS

Elevated serum uric acid (UA) was intimately correlated with vascular stiffness and abnormal ankle brachial index (ABI) in various populations. These correlations lost significance after adjustment for estimated glomerular filtration rate (eGFR), indicating that the association of UA and brachial-ankle pulse wave velocity (baPWV) or ABI might be driven by kidney function. UA is predominantly eliminated through the kidneys, and metabolic disorders can influence the clearance of UA. In this study, we aimed to explore the putative correlation between FEUA and baPWV or ABI to determine to what extent the associations with UA were affected by renal function.

METHODS

This cross-sectional study enrolled 2351 participants, who underwent general health screening in Hanzhong people's hospital from March to June of 2017. BaPWV and ABI were measured using a volume-plethysmographic apparatus (BP-203RPEII; Nihon Colin, Tokyo, Japan). FEUA was divided into quartiles: Q1:FEUA≤3.07; Q2: 3.07<FEUA≤5.32; Q3: 5.32<FEUA≤9.19; and Q4: FEUA> 9.19.

RESULTS

Lower FEUA predicted a higher prevalence of high baPWV and low ABI (p for trend <0.001). The respective ORs for high baPWV from the first to the third quartiles of FEUA were 1.777(1.323, 2.387); 1.561(1.158, 2.104); and 1.680 (1.250, 2.259). The prevalence of low ABI was greatly elevated with the decrement of FEUA [ORs for the first to third FEUA quartiles were 6.977(2.062, 23.610); 5.123(1.475, 17.790); and 2.685(0.709, 10.171), respectively]. The association of FEUA and ABI was independent of related confounding factors. However, the association between FEUA and baPWV was greatly influenced by corresponding confounders, especially gender. The efficacy of FEUA in the prediction of low ABI was stronger than that of serum UA. However, serum UA was more powerful in the prediction of high baPWV.

CONCLUSION

Kidney function exerted a profound influence on the relationship between UA and baPWV or ABI, revealing complex interactions among cardiovascular risk factors.

An association of smoking with serum urate and gout: A health paradox

BACKGROUND

The potential effect of cigarette smoking on levels of serum urate and risk of gout has been considered by a large number of studies, either as the primary variable of interest or as a covariate.

METHODS

Here we systematically review the published evidence relating to the relationship of smoking with serum urate, hyperuricaemia, and gout.

RESULTS

Many studies have reported that smoking reduces serum urate, however, the evidence has not been conclusive with other studies pointing to the opposite or no effect. It has also been suggested that smoking reduces the risk of gout, although there is some evidence to contradict this finding.

CONCLUSION

A consensus has yet to be reached as to the effect of smoking on serum urate levels and the risk of gout.

Prevalence of peripheral artery disease (PAD) and factors associated: An epidemiological analysis from the population-based Screening PRE-diabetes and type 2 DIAbetes (SPREDIA-2) study

AIM

To describe the prevalence of Peripheral Artery Disease (PAD) in a random population sample and to evaluate its relationship with Mediterranean diet and with other potential cardiovascular risk factors such as serum uric acid and pulse pressure in individuals ranged 45 to 74 years.

METHODS

Cross-sectional analysis of 1568 subjects (mean age 6.5 years, 43% males), randomly selected from the population. A fasting blood sample was obtained to determine glucose, lipids, and HbA1C levels. An oral glucose tolerance test was performed in non-diabetic subjects. PAD was evaluated by ankle-brachial index and/or having a prior diagnosis.

RESULTS

PAD prevalence was 3.81% (95% CI, 2.97-4.87) for all participants. In men, PAD prevalence was significantly higher than in women [5.17% (95% CI, 3.74-7.11) vs. 2.78% (95% CI, 1.89-4.07); p = 0.014]. Serum uric acid in the upper quartile was associated with the highest odds ratio (OR) of PAD (for uric acid > 6.1 mg/dl, OR = 4.31; 95% CI, 1.49-12.44). The remaining variables more strongly associated with PAD were: Heart rate >90 bpm (OR = 4.16; 95%CI, 1.62-10.65), pulse pressure in the upper quartile (≥ 54 mmHg) (OR = 3.82; 95%CI, 1.50-9.71), adherence to Mediterranean diet (OR = 2.73; 95% CI, 1.48-5.04), and former smoker status (OR = 2.04; 95%CI, 1.00-4.16).

CONCLUSIONS

Our results show the existence of a low prevalence of peripheral artery disease in a population aged 45-74 years. Serum uric acid, pulse pressure and heart rate >90 bpm were strongly associated with peripheral artery disease. The direct association between Mediterranean diet and peripheral artery disease that we have found should be evaluated through a follow-up study under clinical practice conditions.

Relationship between Serum Uric Acid and Vascular Function and Structure Markers and Gender Difference in a Real-World Population of China-From Beijing Vascular Disease Patients Evaluation Study (BEST) Study

AIM

The study was done to establish the relationship between serum uric acid (UA) and vascular function and structure parameters including carotid femoral pulse wave velocity (CF-PWV), carotid radial pulse wave velocity (CR-PWV), cardio ankle vascular index (CAVI), ankle brachial index (ABI), and carotid intima-media thickness (CIMT), and the gender difference in a real-world population from China.

METHODS

A total of 979 subjects were enrolled (aged 60.86±11.03 years, male 416 and female 563). Value of UA was divided by 100 (UA/100) for analysis.

RESULTS

Body mass index (BMI), diastolic blood pressure (DBP), fasting plasma glucose (FPG), UA, and UA/100 were significantly higher in males compared with females (all p＜0.05); pulse pressure (PP), total cholesterol (TC), high density lipoprotein cholesterol (HDL-C), and low density lipoprotein cholesterol (LDL-C) were lower in males than females (all p＜0.05). All vascular parameters including CF-PWV, CR-PWV, CAVI, ABI, and CIMT were higher in males than females (all p＜0.05). Multiple linear regression analysis showed that UA/100 was independently positively linearly correlated with CAVI (B=0.143, p=0.001) and negatively correlated with ABI in the male population (B=－0.012, p=0.020). In people with higher UA, the risk of higher CF-PWV was 1.593 (p＜0.05).

CONCLUSIONS

1. All vascular parameters were higher in males than females. There was no gender difference in the relationship between UA and vascular markers except in ABI. 2. UA was independently linearly correlated with CAVI. 3. In people with higher UA level, the risk of higher CF-PWV increased. Therefore, higher UA may influence the vascular function mainly instead of vascular structure.

Assessment of Renal Function and Risk Factors for Chronic Kidney Disease in Patients With Peripheral Arterial Disease

Chronic kidney disease (CKD) and peripheral arterial disease (PAD) share common risk factors. We assessed renal function and the prevalence of CKD in patients with PAD and investigated the characteristics of the risk factors for CKD in this population. Renal function of 421 patients with PAD was evaluated. Among the participants, 194 (46.1%) patients had decreased estimated glomerular filtration rate (eGFR). The prevalence of CKD was much higher among patients with PAD. Hypertension (odds ratios [ORs] 2.156, 95% confidence interval [CI] 1.413-3.289, P < .001), serum uric acid (OR 3.794, 95% CI 2.220-6.450, P < .001), and dyslipidemia (OR 1.755, 95% CI 1.123-2.745, P = .014) were significantly associated with CKD and the independent risk factors for CKD in patients with PAD. CKD is common and has a high prevalence in a population with PAD. Patients with PAD may be considered as a high-risk population for CKD. Recognition and modification of risk factors for CKD might beneficially decrease CKD incidence and improve prognosis in patients with PAD.

Incidence of Peripheral Arterial Disease and Its Association with Pulse Pressure: A Prospective Cohort Study

BACKGROUND

The association of pulse pressure and peripheral arterial disease (PAD) has seldom been examined using a prospective design. This study aimed to investigate the association of pulse pressure with PAD incidence in an elderly general population.

METHODS

We utilized data from a cohort conducted in Beijing with additionally 2-year follow-up time. PAD was defined as an ankle brachial index value <0.9 in either leg. Cox proportional hazard regression model was used to quantify the magnitude of pulse pressure on PAD incidence.

RESULTS

During a 2-year follow-up time, 357 of 4,201 (8.5%) participants developed PAD with 105 (6.9%) men and 252 (9.4%) women, respectively. After adjusting for baseline age, sex, body mass index, hypertension, diabetes, total cholesterol, and high-density lipoprotein cholesterol, and smoking, the hazard ratio and 95% confidence interval for people with pulse pressure greater than 60 mmHg was 2.20 (1.53, 3.15) compared with those whose pulse pressure was less than 40 mmHg. A linear trend was observed for the association of pulse pressure with PAD.

CONCLUSION

Higher pulse pressure was associated with higher PAD incidence.

Uric Acid Is Associated With Inflammation, Coronary Microvascular Dysfunction, and Adverse Outcomes in Postmenopausal Women

Uric acid is a risk factor for coronary artery disease in postmenopausal women, but the association with inflammation and coronary endothelial dysfunction (CED) is not well defined. The aim of this study was to determine the relationship of serum uric acid (SUA), inflammatory markers, and CED. In this prospective cohort study, SUA, high-sensitivity C-reactive protein levels, and neutrophil count were measured in 229 postmenopausal women who underwent diagnostic catheterization, were found to have no obstructive coronary artery disease, and underwent coronary microvascular function testing, to measure coronary blood flow response to intracoronary acetylcholine. The average age was 58 years (interquartile range, 52-66 years). Hypertension was present in 48%, type 2 diabetes mellitus in 5.6%, and hyperlipidemia in 61.8%. CED was diagnosed in 59% of postmenopausal women. Mean uric acid level was 4.7±1.3 mg/dL. Postmenopausal women with CED had significantly higher SUA compared with patients without CED (4.9±1.3 versus 4.4±1.3 mg/dL; P=0.02). There was a significant correlation between SUA and percent change in coronary blood flow to acetylcholine (P=0.009), and this correlation persisted in multivariable analysis. SUA levels were significantly associated with increased neutrophil count (P=0.02) and high-sensitivity C-reactive protein levels (P=0.006) among patients with CED, but not among those without CED. SUA is associated with CED in postmenopausal women and may be related to inflammation. These findings link SUA levels to early coronary atherosclerosis in postmenopausal women.

Color Doppler Ultrasound Imaging in the Assessment of Iliac Endofibrosis

Endofibrosis (EF) of the iliac arteries is a flow-limiting condition typically seen in highly trained endurance athletes. Thirty-seven athletes (74 limbs) were referred to our department with suspected EF. All patients had a pre- and postexercise color Doppler ultrasound (CDU) of the iliac arteries. Doppler waveform and peak systolic velocity (PSV) and end-diastolic velocity (EDV) were assessed pre- and postexercise. Endofibrosis was diagnosed with CDU in 24 athletes (29 limbs). Arterial wall and course abnormalities were detected at rest in 20 (67%) symptomatic limbs of athletes with and 4 (22%) symptomatic limbs of athletes without EF. Postexercise abnormal waveforms of the stenotic/damped type were seen in the iliac arteries in all 29 limbs of athletes diagnosed with EF. These waveform changes were accompanied by high PSV (>350 cm/s) and EDV (>150 cm/s), with (n = 10; 34%) or without (n = 19; 66%) the evidence of reduced arterial lumen caliber. Color Doppler ultrasound can be used to detect EF.

A Prediction Model for the Peripheral Arterial Disease Using NHANES Data

We aim to build models for peripheral arterial disease (PAD) risk prediction and seek to validate these models in 2 different surveys in the US general population. Model building survey was based on the National Health and Nutrition Examination Surveys (NHANES, 1999-2002). Potential predicting variables included race, gender, age, smoking status, total cholesterol (TC), body mass index, high-density lipoprotein (HDL), ratio of TC to HDL, diabetes status, HbA1c, hypertension status, and pulse pressure. The PAD was diagnosed as ankle brachial index <0.9. We used multiple logistic regression method for the prediction model construction. The final predictive variables were chosen based on the likelihood ratio test. Model internal validation was done by the bootstrap method. The NHANES 2003-2004 survey was used for model external validation. Age, race, sex, pulse pressure, the ratio of TC to HDL, and smoking status were selected in the final prediction model. The odds ratio (OR) and 95% confidence interval (CI) for age with 10 years increase was 2.00 (1.72, 2.33), whereas that of pulse pressure for 10 mm Hg increase was 1.19 (1.10, 1.28). The OR of PAD was 1.11 (95% CI: 1.02, 1.21) for 1 unit increase in the TC to HDL ratio and was 1.61 (95% CI: 1.40, 1.85) for people who were currently smoking compared with those who were not. The respective area under receiver operating characteristics (AUC) of the final model from the training survey and validation survey were 0.82 (0.82, 0.83) and 0.76 (0.72, 0.79) indicating good model calibrations. Our model, to some extent, has a moderate usefulness for PAD risk prediction in the general US population.

Complex nonlinear autonomic nervous system modulation link cardiac autonomic neuropathy and peripheral vascular disease

BACKGROUND

Physiological interactions are abundant within, and between, body systems. These interactions may evolve into discrete states during pathophysiological processes resulting from common mechanisms. An association between arterial stenosis, identified by low ankle-brachial pressure index (ABPI) and cardiovascular disease (CVD) as been reported. Whether an association between vascular calcification-characterized by high ABPI and a different pathophysiology-is similarly associated with CVD, has not been established. The current study aims to investigate the association between ABPI, and cardiac rhythm, as an indicator of cardiovascular health and functionality, utilizing heart rate variability (HRV).

METHODS AND RESULTS

Two hundred and thirty six patients underwent ABPI assessment. Standard time and frequency domain, and non-linear HRV measures were determined from 5-min electrocardiogram. ABPI data were divided into normal (n = 101), low (n = 67) and high (n = 66) and compared to HRV measures.(DFAα1 and SampEn were significantly different between the low ABPI, high ABPI and control groups (p < 0.05).

CONCLUSION

A possible coupling between arterial stenosis and vascular calcification with decreased and increased HRV respectively was observed. Our results suggest a model for interpreting the relationship between vascular pathophysiology and cardiac rhythm. The cardiovascular system may be viewed as a complex system comprising a number of interacting subsystems. These cardiac and vascular subsystems/networks may be coupled and undergo transitions in response to internal or external perturbations. From a clinical perspective, the significantly increased sample entropy compared to the normal ABPI group and the decreased and increased complex correlation properties measured by DFA for the low and high ABPI groups respectively, may be useful indicators that a more holistic treatment approach in line with this more complex clinical picture is required.