Smoking status and endothelial function in Japanese men

The association between smoking exposure and endothelial function evaluated using flow-mediated dilation values: a meta-analysis

BACKGROUND

Tobacco use is recognized as a major cause of cardiovascular disease, which is associated with endothelial dysfunction. Endothelial function is evaluated using flow-mediated dilation (FMD), which is a noninvasive method. This meta-analysis aimed to investigate the association between smoking exposure and endothelial function evaluated using FMD values.

METHODS

We searched the PubMed, Embase, Web of Science, and Cochrane Library databases for cohort studies of smokers or passive smokers that used FMD to assess endothelial function. The primary outcome of the study was the change in the rate of FMD. The risk of bias was evaluated using the Cochrane Collaboration tool and Newcastle-Ottawa Scale. Further, the weighted mean difference was used to analyze the continuous data.

RESULTS

Overall, 14 of 1426 articles were included in this study. The results of these articles indicated that smoking is a major cause of endothelial dysfunction and altered FMD; a pooled effect size of - 3.15 was obtained with a 95% confidence interval of (- 3.84, - 2.46). Notably, pregnancy status, Asian ethnicity, or health status did not affect heterogeneity.

CONCLUSIONS

We found that smoking has a significant negative impact on FMD, and measures such as medication or education for smoking cessation may improve endothelial function and reduce the risk of cardiovascular disease.

TRIAL REGISTRATION

The meta-analysis was registered with PROSPERO on April 5th, 2023 (CRD42023414654).

Association of cumulative low-density lipoprotein cholesterol exposure with vascular function

BACKGROUND

The relationship between cumulative low-density lipoprotein cholesterol (LDL-C) exposure and progression of atherosclerosis remains uncertain.

OBJECTIVE

The aim of this study was to determine the relationship between cumulative LDL-C level and flow-mediated vasodilation (FMD), nitroglycerine-induced vasodilation (NID) and the presence of plaque in the common carotid artery (CCA).

METHODS

This was a cross-sectional study. We measured FMD in 8208 subjects, NID in 1822 subjects, and CCA plaque in 591 subjects who were not taking lipid-lowering drugs. The subjects were divided into four groups based on cumulative LDL-C exposure: <4000 mg·year/dL, 4000-4999 mg·year/dL, 5000-5999 mg·year/dL, and ≥6000 mg·year/dL.

RESULTS

The odds ratio of the lower quartile of FMD in the cholesterol-year-score <4000 mg·year/dL group was significantly higher than the odds ratios in the other groups. The odds ratio of the lower quartile of NID in the <4000 mg·year/dL group was significantly higher than the odds ratios in the 5000-5999 mg·year/dL and ≥6000 mg·year/dL groups. The odds ratio of the prevalence of CCA plaque in the <4000 mg·year/dL group was significantly higher than that in the ≥6000 mg·year/dL group.

CONCLUSIONS

Endothelial dysfunction occurred from cumulative LDL-C exposure of 4000 mg·year/dL, vascular smooth muscle dysfunction occurred from cumulative LDL-C exposure of 5000 mg·year/dL, and prevalence of CCA plaque occurred from cumulative LDL-C exposure of 6000 mg·year/dL. CLINICAL TRIAL REGISTRY INFORMATION: http://www.umin.ac.jp (UMIN000012950, UMIN000012951, and UMIN000012952, UMIN000003409).

Smoking cessation and vascular endothelial function

Smoking is associated with vascular endothelial dysfunction. It is thought that smoking impairs vascular endothelial function through a decrease in nitric oxide bioavailability induced by activation of oxidative stress and inflammation. Endothelial dysfunction can be improved or augmented by appropriate interventions including pharmacotherapy, administration of supplements and lifestyle modifications. Although there have not been many studies, the effects of smoking cessation on endothelial function have been shown. In those studies, it was shown that smoking cessation does not always have a positive effect on vascular endothelial function. In this review, I will focus on the role of smoking in endothelial function and the effects of smoking cessation on endothelial function. Smoking impairs vascular endothelial function and leads to atherosclerosis. Smoking cessation is expected to improve vascular endothelial function. Effects of smoking cessation on endothelial function are not always consistent. Further studies are needed to determine whether smoking cessation directly improves endothelial function. NO indicates nitric oxide.

Vascular Endothelial Function Is Associated with eGFR Slope in Female and Non-Smoking Male Individuals with Cardiovascular Risk Factors: A Pilot Study on the Predictive Value of FMD for Renal Prognosis

AIMS

It is known that there are sex differences in vascular endothelial function and the development of chronic kidney diseases; however, it remains unclear whether sex differences influence the association between vascular endothelial function and renal prognosis.

METHODS

To clarify the relationship between vascular endothelial function and longitudinal eGFR changes in male and female patients with cardiovascular risk factors, we retrospectively evaluated 341 patients (176 males and 165 females) with cardiovascular risk factors in whom vascular function was assessed by flow-mediated dilation (FMD) and brachial-ankle pulse wave velocity (baPWV) and in whom 24-month longitudinal eGFR values were recorded after the vascular function examinations. Associations of values of FMD and baPWV with values of eGFR slope were statistically analyzed.

RESULTS

Simple regression analysis showed that the value of FMD was positively associated with eGFR slope in females (p=0.001) and non-smoking males (p=0.033) but not in smoking males. Multiple regression analysis showed that the value of FMD remains a positive contributor for eGFR slope in females (p=0.001) and non-smoking males (p=0.045) but not in smoking males. In contrast, values of baPWV had no significant association with eGFR slope regardless of sex and cigarette smoking.

CONCLUSIONS

In individuals with cardiovascular risk factors, evaluation of vascular endothelial function enables prediction of renal prognosis in females and non-smoking males.

An evaluation method for HMI of deep-sea manned submersible based on human reliability

Improving the human reliability of the human-machine interface (HMI) of deep-sea manned submersible is of great importance for the development of the deep-sea field. Based on the SHEL (Software S, Hardware H, Environment E, Liveware L) model, this study classifies the performance shaping factors (PSF) that affect the human reliability of submersible HMIs and builds a PSF system. The interpretative structural model (ISM) is used to matrix the interactions between the elements that make up the system of PSF. A multi-level recursive structure is obtained by building the corresponding adjacency matrix. The Noisy-OR model is introduced to construct a Bayesian network in order to build a new HMI evaluation method. A real case of Bayesian network causal inference verifies the validity of the built method. This study proposes a set of HMI human reliability evaluation methods applicable to deep-sea manned submersible, which provides a new idea for human reliability assessment.

Tobacco smoking and vascular biology and function: evidence from human studies

Tobacco cigarette smoking is among the most complex and least understood health risk factors. A deeper insight into the pathophysiological actions of smoking exposure is of special importance as smoking is a major cause of chronic non-communicable diseases, in particular of cardiovascular disease as well as risk factors such as atherosclerosis and arterial hypertension. It is well known that smoking exerts its negative effects on cardiovascular health through various interdependent pathophysiological actions including hemodynamic and autonomic alterations, oxidative stress, inflammation, endothelial dysfunction, thrombosis, and hyperlipidemia. Importantly, impaired vascular endothelial function is acknowledged as an early key event in the initiation and progression of smoking-induced atherosclerosis. Increasing evidence from human studies indicates that cigarette smoke exposure associates with a pathological state of the vascular endothelium mainly characterized by reduced vascular nitric oxide bioavailability due to increased vascular superoxide production. In the present overview, we provide compact evidence on the effects of tobacco cigarette smoke exposure on vascular biology and function in humans centered on main drivers of adverse cardiovascular effects including endothelial dysfunction, inflammation, and oxidative stress.

Obesity and Endothelial Function

Obesity is a major public health problem and is related to increasing rates of cardiovascular morbidity and mortality. Over 1.9 billion adults are overweight or obese worldwide and the prevalence of obesity is increasing. Obesity influences endothelial function through obesity-related complications such as hypertension, dyslipidemia, diabetes, metabolic syndrome, and obstructive sleep apnea syndrome. The excess fat accumulation in obesity causes adipocyte dysfunction and induces oxidative stress, insulin resistance, and inflammation leading to endothelial dysfunction. Several anthropometric indices and imaging modalities that are used to evaluate obesity have demonstrated an association between obesity and endothelial function. In the past few decades, there has been great focus on the mechanisms underlying endothelial dysfunction caused by obesity for the prevention and treatment of cardiovascular events. This review focuses on pathophysiological mechanisms of obesity-induced endothelial dysfunction and therapeutic targets of obesity.

Relationship of Daily Coffee Intake with Vascular Function in Patients with Hypertension

We evaluated the relationship of daily coffee intake with endothelial function assessed by flow-mediated vasodilation and vascular smooth muscle function assessed by nitroglycerine-induced vasodilation in patients with hypertension. A total of 462 patients with hypertension were enrolled in this cross-sectional study. First, we divided the subjects into two groups based on information on daily coffee intake: no coffee group and coffee group. The median coffee intake was two cups per day in the coffee group. There were significant differences in both flow-mediated vasodilation (2.6 ± 2.8% in the no coffee group vs. 3.3 ± 2.9% in the coffee group, p = 0.04) and nitroglycerine-induced vasodilation (9.6 ± 5.5% in the no coffee group vs. 11.3 ± 5.4% in the coffee group, p = 0.02) between the two groups. After adjustment for confounding factors, the odds ratio for endothelial dysfunction (OR: 0.55, 95% CI: 0.32–0.95) and the odds ratio for vascular smooth muscle dysfunction (OR: 0.50, 95% CI: 0.28–0.89) were significantly lower in the coffee group than in the no coffee group. Next, we assessed the relationship of the amount of daily coffee intake with vascular function. Cubic spline curves revealed that patients with hypertension who drank half a cup to 2.5 cups of coffee per day had lower odds ratios for endothelial dysfunction assessed by flow-mediated vasodilation and vascular smooth muscle dysfunction assessed by nitroglycerine-induced vasodilation. Appropriate daily coffee intake might have beneficial effects on endothelial function and vascular smooth muscle function in patients with hypertension.

Prevalence and risk factors for vascular calcification based on the ankle-brachial index in the general population: a cross-sectional study

Background

To investigate the prevalence of vascular calcification based on the ankle‐brachial index (ABI) value and analyse the risk factors for vascular calcification in the general population.

Methods

A cross-sectional study was conducted to collect clinical, laboratory, and lifestyle data in individuals aged 30–70 recruited from the physical examination centre. The automatic arteriosclerosis detector was used to measure the ABI. Difference tests, correlation analyses, and multivariate logistic regression analyses were performed to identify risk factors for vascular calcification.

Results

The overall prevalence of vascular calcification was 24.39% in 1033 subjects. The prevalence of vascular calcification in males was much higher than that in females (27.80% vs. 17.49%, P < 0.001). The differences in age, body mass index (BMI), systolic blood pressure (SBP), diastolic blood pressure (DBP), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), hypertension, and fatty liver disease were statistically significant in males (P < 0.05). The differences between serum uric acid (UA), total cholesterol (TC), TG, low-density lipoprotein cholesterol (LDL-C), estimated glomerular filtration rate (eGFR), alcohol consumption, exercise, and postmenopausal status were statistically significant in females (P < 0.05). Increased age (odds ratio (OR) = 1.028, 95% confidence interval (CI) 1.008–1.049, P = 0.007), increased BMI (OR = 1.238, 95% CI 1.147–1.337, P < 0.001) and elevated DBP (OR = 2.563, 95% CI 1.262–5.205, P = 0.009) were independent risk factors for vascular calcification in males after adjusting for confounding factors. Increased BMI (OR = 1.159, 95% CI 1.029–1.304, P = 0.015), elevated UA (OR = 1.545, 95% CI 1.077–2.216, P = 0.018), elevated LDL-C (OR = 1.044, 95% CI 1.060–1.027, P < 0.001), and a lack of exercise (OR = 2.402, 95% CI 1.073–5.373, P = 0.033) were independent risk factors for vascular calcification in females.

Conclusions

The prevalence of vascular calcification based on the ABI value is also high in the general population of our centre. Increased age, BMI, and elevated DBP are independent risk factors for vascular calcification in males. Increased BMI, UA, LDL-C, and a lack of exercise are independent risk factors for vascular calcification in females. Attention should be given to strengthening the prevention and control of vascular calcification in the general population.

White blood cell count is not associated with flow-mediated vasodilation or nitroglycerine-induced vasodilation

It is well known that white blood cell (WBC) count is an independent predictor of cardiovascular events. However, associations of WBC count and WBC subtypes with endothelial function assessed by flow-mediated vasodilation (FMD) and vascular smooth muscle function assessed by nitroglycerine-induced vasodilation (NID) are unclear. The aim of this study was to determine the relationships of WBC count and WBC subtypes with vascular function assessed by FMD and NID. A total of 1351 subjects in whom FMD and NID had been measured were recruited from Hiroshima University Vascular Registry. Mean values were 3.7 ± 2.8% for FMD and 11.8 ± 5.9% for NID. WBC was not correlated with FMD or NID. NID was significantly correlated with lymphocytes in univariate analysis but not with other hematologic parameters. In multiple linear regression analyses, NID was not correlated with lymphocytes. In all subgroups including subgroups of age, gender, body mass index, hypertension, dyslipidemia, diabetes mellitus, smoking and tertile of WBC count, WBC count was not correlated with FMD or NID. WBC count and WBC subtypes were not associated with endothelial function assessed by FMD or vascular smooth muscle function assessed by NID. WBC count and vascular function assessed by FMD and NID may reflect different aspects of atherosclerosis.

Clinical Trial Registration Information: URL for Clinical Trial: http://www.umin.ac.jp Registration Number for Clinical Trial: UMIN000039512.

Self-reported total sitting time on a non-working day is associated with blunted flow-mediated vasodilation and blunted nitroglycerine-induced vasodilation

We divided the 466 subjects into two groups based on information on sitting time on a non-working day and evaluated flow-mediated vasodilation (FMD) and nitroglycerine-induced vasodilation (NID). FMD was smaller in subjects with sitting time on a non-working day of ≥6 h/day than in subjects with sitting time on a non-working day of <6 h/day (2.5 ± 2.6% vs. 3.7 ± 2.9%; p < 0.001). NID was smaller in subjects with sitting time at non-working day of ≥ 8 h/day than in subjects with sitting time on a non-working day of < 8 h/day (10.1 ± 5.6% vs. 11.5 ± 5.0%; p = 0.01). After adjustment for confounding factors for vascular function, the odds of having the lowest tertile of FMD was significantly higher in subjects with sitting time on a non-working day of ≥6 h/day than in subjects with sitting time on a non-working day of <6 h/day. The odds of having the lowest tertile of NID was significant higher in subjects with sitting time on a non-working day of ≥ 8 h/day than in subjects with sitting time on a non-working day of < 8 h/day. These findings suggest that prolonged sitting time on a non-working day is associated with blunted FMD and blunted NID.

Smoking: Pathogenetic Mechanisms, Possibilities of Medical Correction (Literature Review)

The smoking epidemic is one of the greatest threats to human health, as it is the leading cause of death worldwide, as well as many preventable diseases. Diseases associated with smoking include cardiovascular disease, atherosclerosis, type 2 diabetes, chronic pancreatitis, chronic obstructive pulmonary disease, cancer, osteoporosis and others. The aim is to analyze information on the pathogenetic mechanisms of tobacco exposure and methods of its drug correction. Among the 4,000 chemicals identified in tobacco smoke, nicotine is the main active ingredient in tobacco products. It is highly toxic and potentially lethal. Nicotine affects many systems, including the neurological, neuromuscular, cardiovascular, respiratory, immunological and gastrointestinal systems. Therefore, nicotine-containing drugs reduce the symptoms of nicotine withdrawal in regular smokers who abstain from smoking. The presence of different types of nicotinic acetylcholine receptors, their regulation and desensitization affect these complex physiological effects. Nicotine replacement drugs contain pure nicotine, in order to reduce the patient’s propensity to use tobacco, physiological and psychomotor withdrawal symptoms. They increase the level of nicotine in the blood, thus facilitating the transition from cigarette smoking to complete abstinence. Smokers can quit without using nicotine-containing drugs, but most those who try do not succeed on the first try. Nicotine replacement drugs only affect physical dependence. Nicotine is the main factor responsible for dependence on cigarette smoking, and its rate of absorption and entry into the brain are considered key factors responsible for the high potential for abuse of this drug. The advantage of nicotine-containing drugs is the patient’s independence from the method of administration, determination of abstinence, duration of treatment, level of supportive counseling, place of treatment (hospital, clinic or support group), as well as fixed, variable or reduced doses. There are a number of nicotine-containing drugs in various forms that effectively promote smoking cessation in adults.