Passive smoking and stroke in men and women: a national population-based case-control study in China

Health effects associated with exposure to secondhand smoke: a Burden of Proof study

Despite a gradual decline in smoking rates over time, exposure to secondhand smoke (SHS) continues to cause harm to nonsmokers, who are disproportionately children and women living in low- and middle-income countries. We comprehensively reviewed the literature published by July 2022 concerning the adverse impacts of SHS exposure on nine health outcomes. Following, we quantified each exposure-response association accounting for various sources of uncertainty and evaluated the strength of the evidence supporting our analyses using the Burden of Proof Risk Function methodology. We found all nine health outcomes to be associated with SHS exposure. We conservatively estimated that SHS increases the risk of ischemic heart disease, stroke, type 2 diabetes and lung cancer by at least around 8%, 5%, 1% and 1%, respectively, with the evidence supporting these harmful associations rated as weak (two stars). The evidence supporting the harmful associations between SHS and otitis media, asthma, lower respiratory infections, breast cancer and chronic obstructive pulmonary disease was weaker (one star). Despite the weak underlying evidence for these associations, our results reinforce the harmful effects of SHS on health and the need to prioritize advancing efforts to reduce active and passive smoking through a combination of public health policies and education initiatives.

Eating Behaviors, Lifestyle, and Ischemic Stroke: A Lebanese Case-Control Study

BACKGROUND

Stroke is the second leading cause of death and the third leading cause of disability on a global scale. Most clinicians tend to underestimate the importance of diet and inadequate or dysfunctional eating attitudes in patients with a complicated relationship with food. Concerned about the potential of an independent Lebanese approach, and also because prior international research has revealed a link between eating intake or choice and ischemic stroke risk, it was considered vital to broaden the scope of the literature and evaluate further the association of disordered eating attitudes and focus on the distinct relationship with food in the case of orthorexia nervosa (ON) in the Lebanese community. Consequently, the purpose of the present study is to investigate the potential association between pre-existing disordered eating attitudes, specifically ON, and ischemic stroke risk, with an emphasis on the evidence supporting a Mediterranean-style diet.

METHODS

This research is a case-control survey study involving 113 Lebanese individuals with ischemic stroke and 451 age-(within 5 years) and sex-matched controls recruited from several hospitals in Lebanon (April 2020-April 2021).

RESULTS

According to the findings of our first regression model, living 100 m from a crowded road (adjusted odds ratio [aOR]: 3.421, 95% confidence interval [CI]: 1.585-7.387), living 100 m from an electricity generator (aOR: 3.686, 95% CI: 1.681-8.085), higher waterpipe dependence (aOR: 1.204, 95% CI: 1.117-1.297), higher exposure to passive smoking (aOR: 2.651, 95% CI: 2.051-3.426), being married (aOR: 3.545, 95% CI: 1.297-9.689), having a low educational attainment (aOR: 0.239, 95% CI: 0.084-0.679), vigorous physical activity (aOR: 1.003, 95% CI: 1.001-1.006), and having more inappropriate eating (aOR: 1.040, 95% CI: 1.006-1.074) were all associated with higher odds of having ischemic stroke. Furthermore, atrial fibrillation (aOR: 2.945, 95% CI: 1.010-8.585), diabetes (aOR: 2.550, 95% CI: 1.169-5.561), heart diseases (aOR: 6.193, 95% CI: 2.196-17.463), and hypertension (aOR: 2.744, 95% CI: 1.049-7.180) were also linked to an increased risk of stroke. Moreover, having more orthorexia nervosa tendencies (aOR: 1.123, 95% CI: 1.021-1.235) was related to a higher odds of having an ischemic stroke, whereas better adherence to the MeD was significantly linked (aOR: 0.691, 95% CI: 0.583-0.819) to lower odds of ischemic stroke.

CONCLUSIONS

Ischemic stroke patients were more likely to have disordered eating attitudes and orthorexic behaviors. Furthermore, the MeD has been found to be beneficial in reducing ischemic stroke risk. Despite the study's focus, outdoor pollution, waterpipe dependence, and passive smoking were linked to ischemic stroke. In summary, this review suggests that improving one's nutritional status and making a few lifestyle changes are key stroke prevention and treatment methods.

Age at menarche, age at menopause, reproductive years and risk of fatal stroke occurrence among Chinese women: the Guangzhou Biobank Cohort Study

Background

The relationship between women’s reproductive characteristics and stroke events is unclear. We aimed to investigate age at menarche, age at menopause and number of reproductive years in relation to fatal stroke occurrence in the Guangzhou Biobank Cohort Study.

Methods

In total, 16,504 postmenopausal women without stroke, heart disease or a cancer history at baseline were included and followed up for a median of 12.0 years. After review of available records, 222 stroke deaths were recorded. Cox proportional hazards regression was used to assess the associations between the risk of fatal stroke occurrence and age at menarche, age at menopause and number of reproductive years.

Results

In the whole cohort, compared with those aged 15 years at menarche, an increased risk of fatal stroke among women at menarche showed respectively in those aged 12 years (aHR (adjusted hazard ratio) = 1.86, 95% confidence interval (CI) 0.96–3.60), aged 13 years (aHR = 1.69, 95% CI 0.98–2.92), aged 17 years (aHR = 1.83, 95% CI 1.10–3.05) and aged ≥ 18 years (aHR = 1.66, 95% CI 1.03–2.70), wherein the associations revealed an atypically U-shaped; similar U-shaped association to the cohort of postmenopausal women born before 1940 released a range of incremental risks of fatal stroke in women at menarche aged ≤ 12 years (aHR = 3.68, 95% CI 1.68–8.05), aged 13 years (aHR = 2.11, 95% CI 1.02–4.34), aged 14 years (aHR = 2.07, 95% CI 1.04), aged 17 years (aHR = 2.30, 95% CI 1.20–4.39) and aged 18 years (aHR = 2.50, 95% CI 1.37–4.57), respectively. Compared with menopausal women aged 51–52 years, those aged < 43 years at menopause had an increased risk for fatal stroke among postmenopausal women born in and after 1940 (aHR = 1.64, 95% CI 0.97–2.78) and postmenopausal women born before 1940 (aHR = 1.97, 95% CI 1.05–3.69). Additionally, compared with those with 32–34 reproductive years, women with ≤ 28 reproductive years had an increased risk for fatal stroke in the whole cohort (aHR = 1.91, 95% CI 1.28–2.86) and the cohort of postmenopausal women born before 1940 (aHR = 1.79, 95% CI 1.15–2.80).

Conclusions

Younger and older age at menarche, younger age at menopause and fewer reproductive ages were related to an increased risk of fatal stroke in postmenopausal women.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12905-021-01579-9.

Tobacco-related cardiovascular risk in women: New issues and therapeutic perspectives

BACKGROUND

Smoking is the main modifiable risk factor for stroke and myocardial infarction, particularly in women; its prevalence in France is evolving, and new patterns of nicotine consumption have emerged.

AIMS

To present contemporary data on smoking prevalence and the use of electronic cigarettes, and to describe current knowledge of the cardiovascular risk specificities and the effectiveness of withdrawal methods in women.

METHOD

We identified studies by searching the MEDLINE bibliographic database between 1995 and 2020, and the Weekly Epidemiological Bulletin (Bulletin Épidémiologique Hebdomadaire) published by the French health authorities.

RESULT

In recent years, smoking prevalence among French women has decreased overall, except in the oldest age group (aged>55 years). At the same time, the incidence of hospitalization for cardiovascular events has increased worryingly among women smokers aged<65 years. Active smoking in women is associated with an increased risk of premature myocardial infarction, and a risk of stroke that increases with the number of cigarettes consumed per day; it is also responsible for increased cardiovascular events in women taking oestrogen-progestin contraception. Quitting smoking reverses these effects in the long term, and women are just as likely to quit smoking as men.

CONCLUSIONS

Stopping smoking must be a priority objective for women smokers, for primary and secondary prevention, and they should systematically be offered a validated method of cessation or even electronic cigarettes.

Tobacco Use: A Major Risk Factor of Intracerebral Hemorrhage

Spontaneous intracerebral hemorrhage (sICH) is one of the deadliest subtypes of stroke, and no treatment is currently available. One of the major risk factors is tobacco use. In this article, we review literature on how tobacco use affects the risk of sICH and also summarize the known effects of tobacco use on outcomes following sICH. Several studies demonstrate that the risk of sICH is higher in current cigarette smokers compared to non-smokers. The literature also establishes that cigarette smoking not only increases the risk of sICH but also increases hematoma growth, results in worse outcomes, and increases the risk of death from sICH. This review also discusses potential mechanisms activated by tobacco use which result in an increase in risk and severity of sICH. Exploring the underlying mechanisms may help alleviate the risk of sICH in tobacco users as well as may help better manage tobacco user sICH patients.

Dose-related effect of secondhand smoke on cardiovascular disease in nonsmokers: Systematic review and meta-analysis

BACKGROUND

Despite the positive association between secondhand smoke (SHS) and cardiovascular diseases (CVD), no comprehensive assessment on the dose-response relationship between SHS and CVD has yet been reported. Therefore, a meta-analysis was conducted to update the binary association, and to elucidate the dose-response relationship of both self-reported and objectively measured SHS exposure with CVD.

METHODS

PubMed and Embase databases were searched for articles published up to November 12, 2019. Random-effects models were used to assess the summary odds ratios (ORs) of CVD with SHS exposure. Restricted cubic splines were used to fit the dose-response relationship.

RESULTS

Fifty-five eligible observational studies were included in this meta-analysis to investigate the association between SHS exposure and CVD. Based on the meta-analysis, the pooled OR of CVD was 1.22 (95% CI 1.17-1.28) for the self-reported SHS individuals as comparing to the non-exposed group. The result of restricted cubic splines showed a risk plateau of SHS exposure at 15 cigarettes per day (P_{non-linearity} = 0.042), while other characteristics s of SHS exposure (amount, daily and cumulative duration, and cotinine) were in linear relationships with CVD (P_{non-linearity} >0.05). In addition, an estimated of 6.77% (95% CI: 5.31%-8.46%) of all CVD cases in men and 7.15% (95% CI: 5.62%-8.93%) in women might be attributed to SHS exposure worldwide.

CONCLUSIONS

Exposure to SHS is associated with an increased risk of CVD regardless of the modes. And thus, well-enforced smoke-free laws could possibly reduce a substantial risk of CVD caused by SHS.

Scavenger Receptor Class B type 1 (SR-B1) and the modifiable risk factors of stroke

Stroke is a devastating disease that occurs when a blood vessel in the brain is either blocked or ruptured, consequently leading to deficits in neurological function. Stroke consistently ranked as one of the top causes of mortality, and with the mean age of incidence decreasing, there is renewed interest to seek novel therapeutic treatments. The Scavenger Receptor Class B type 1 (SR-B1) is a multifunctional protein found on the surface of a variety of cells. Research has found that that SR-B1 primarily functions in an anti-inflammatory and anti-atherosclerotic capacity. In this review, we discuss the characteristics of SR-B1 and focus on its potential correlation with the modifiable risk factors of stroke. SR-B1 likely has an impact on stroke through its interaction with smoking, diabetes mellitus, diet, physical inactivity, obesity, hypercholesterolemia, atherosclerosis, coronary heart disease, hypertension, and sickle cell disease, all of which are critical risk factors in the pathogenesis of stroke.

"Smoking paradox" is not true in patients with ischemic stroke: a systematic review and meta-analysis

Background

Ischemic stroke (IS) is a common cause of death from vascular diseases. Studies have found that smoking increases the risk of ischemic stroke, but the association of smoking with the outcome of IS remains unclear. This meta-analysis aims to investigate the effect of smoking on the prognosis of IS.

Methods

We searched four electronic databases including PubMed, EMBASE, Cochrane library and Web of science for papers, published before January 2019. In this meta-analysis, Review Manager 5.3 software was used to calculate for the pooled estimate effect, as well as the inverse-variance method for pooled mean difference (MD) and odds ratio (OR) of incidence in two groups of population.

Results

A total of 14,789 citations were identified during the literature search, 21 studies were included in the meta-analyses after screening. The full-adjusted OR of poor prognostic outcome in smoking and nonsmoking patients with stroke was pooled as 0.96 (95% CI 0.77–1.21), suggested that smoking or not has no impact on prognosis of IS. The pooled MD of onset age between smoking and nonsmoking IS patients was − 10.05 (− 12.91, − 7.19), indicated that smoking causes first onset of IS to occur 10 years earlier.

Conclusions

This meta-analysis showed that smoking was not a protective factor for poor prognosis of IS. Smoking patients with IS are 10 years younger than nonsmoking patients at time of the first onset of stroke.

Is exposure to tobacco associated with extrahepatic cholangiocarcinoma epidemics? A retrospective proportional mortality study in China

Background

Extrahepatic cholangiocarcinoma (ECC) has become one of the most rapidly increasing malignancies in China during recent decades. The relationship between tobacco exposure and ECC epidemics is unclear; this study aimed to explore this relationship.

Methods

We included 55,806 participants aged 30 years or older from the National Mortality and Smoking Survey of China. Smoking in participants and spouses was defined as 1 cigarette or more per day for up to 1 year. Spouses’ smoking was taken as a measure of exposure to passive smoking. Smoking information in 1980 was ascertained and outcomes were defined as ECC mortality during 1986–1988.

Results

We found that either passive or active smoking increased the risk of death from ECC by 20% (risk ratio [RR], 1.20; 95% confidence interval [CI], 0.99–1.47), compared with no exposure to any tobacco. This risk was a notable 98% (RR, 1.98; 95% CI, 1.49–2.64) for individuals exposed to passive plus active smoking. These findings were highly consistent among men and women. Pathology-based analyses showed dose-response relationships of ECC with pack-years for all types of smoking exposure (Ps for trend < 0.05); the RR reached 2.75 (95% CI, 1.20–6.30) in individuals exposed to combined smoking with the highest exposure dose. The findings were similar for non-pathology-based analysis.

Conclusions

This study indicates that tobacco exposure increases ECC risk. Given the dramatic increase of exposure to secondhand smoke and patients with ECC, an inadequate provision of smoke-free environments could be contributing to ECC epidemics and could further challenge public health and medical services, based on the current disease spectrum.

Electronic supplementary material

The online version of this article (10.1186/s12885-019-5484-9) contains supplementary material, which is available to authorized users.

The relationship between smoking and stroke: A meta-analysis

BACKGROUND

Stroke is one of the leading causes of death and disability for adult men and women worldwide, and a number of studies have explored the influences of smoking on stroke. However, few studies have discussed the relationship between stroke and smoking with consideration of the following factors: sex, the number of cigarettes smoked per day, stroke subtype, and the follow-up duration. Consequently, we aimed to extend previous work by using a systematic review to explore the relationship between stroke and cigarette smoking in reference to the above factors.

METHODS

A systematic review was conducted using the PubMed, Embase, and Cochrane Central Register databases and the following search criteria: ["stroke" (MeSH) and "smoking" (MeSH)]. All analyses were conducted with Stata, and funnel plots and Egger regression asymmetry tests were used to assess publication bias.

RESULTS

The meta-analysis included 14 studies involving 303134 subjects. According to the meta-analysis, smokers had an overall increased risk of stroke compared with nonsmokers, with a pooled odds ratio (OR) of 1.61 (95% confidence interval [CI]: 1.34-1.93, P < .001). A subgroup analysis conducted based on smoking status revealed ORs of 1.92 (95% CI: 1.49-2.48) for current smokers and 1.30 (95% CI: 0.93-1.81) for former smokers. In addition, the relationship between stroke of any type and smoking status was also statistically significant; current smokers had an increased risk of stoke compared with nonsmokers (OR: 1.46, 95% CI: 1.04-2.07, P < .001), which was influenced by sex (men: OR: 1.54, 95% CI: 1.11-2.13, P = .002; women: OR: 1.88, 95% CI: 1.45-2.44, P < .023). From the analysis, we also observed that passive smoking increased the overall risk of stroke by 45% (OR: 1.45, 95% CI: 1.0-2.11, P < .05). Based on the dose-response meta-analysis, the risk of stroke increased by 12% for each increment of 5 cigarettes per day.