Secondhand smoking and neurological disease: a meta-analysis of cohort studies

Smoke-free hospitality environments and cognitive health: A population-based study in the United States

Introduction

Cigarette smoking is among the largest risk factors for cognitive decline in later life. This study examines the associations between hospitality smoke-free coverage in the US and the prevalence of self-rated cognitive function decline and disparities therein.

Methods

I use the repeated cross-sectional Behavioral Risk Factor Surveillance data collected between 2017 and 2022 from a sample of Americans 45 years and older and estimate logistic regression models predicting self-rated cognitive function decline by calculated smoke-free hospitality coverage in restaurants and bars.

Results

Fully adjusted models indicate a marginally statistically significant 0.16 percentage point reduction [CI -0.35 to 0.02] in the probability of self-rated cognitive function decline for a 10 % increase in the smoke-free bar coverage. The effect is statistically significant and larger for women, a 0.29 [CI -0.50 to -0.01] percentage point decrease, and for non-smokers, a 0.35 [CI -0.56 to -0.15] percentage point decrease. I do not find a parallel effect of smoke-free restaurant laws and I find no effect of either law on self-rated cognitive function decline-related limitations in daily life for either hospitality law.

Conclusions

The findings suggest that smoke-free bar laws could play a role in preventing cognitive decline among older adults in the United States. Effective public health strategies against cognitive decline should include both targeted and broad-based policy measures.

A comprehensive analysis of the health effects associated with smoking in the largest population using UK Biobank genotypic and phenotypic data

Background

Smoking is a widespread behavior, while the relationship between smoking and various diseases remains a topic of debate.

Objective

We conducted analysis to further examine the identified associations and assess potential causal relationships.

Methods

We utilized seven single nucleotide polymorphisms (SNPs) known to be linked to smoking extracting genotype data from the UK Biobank, a large-scale biomedical repository encompassing comprehensive health-related and genetic information of European descent. Phenome-wide association study (PheWAS) analysis was conducted to map the association of genetically predicted smoking status with 1,549 phenotypes. The associations identified in the PheWAS were then meticulously examined through two-sample Mendelian randomization (MR) analysis, utilizing data from the UK Biobank (n = 487,365) and the Sequencing Consortium of Alcohol and Nicotine Use (GSCAN) (n = 337,334). This approach allowed us to comprehensively characterize the links between smoking and disease patterns.

Results

The PheWAS analysis produced 34 phenotypes that demonstrated significant associations with smoking (P = 0.05/1460). Importantly, sickle cell anemia and type 2 diabetes exhibited the most significant SNPs (both 85.71% significant SNPs). Furthermore, the MR analyses provided compelling evidence supporting causal associations between smoking and the risk of following diseases: obstructive chronic bronchitis (IVW: Beta = 0.48, 95% confidence interval (CI) 0.36-0.61, P = 1.62×10-13), cancer of the bronchus (IVW: Beta = 0.92, 95% CI 0.68-1.17, P = 2.02×10-13), peripheral vascular disease (IVW: Beta = 1.09, 95% CI 0.71-1.46, P = 1.63×10-8), emphysema (IVW: Beta = 1.63, 95% CI 0.90-2.36, P = 1.29×10-5), pneumococcal pneumonia (IVW: Beta = 0.30, 95% CI 0.11-0.49, P = 1.60×10-3), chronic airway obstruction (IVW: Beta = 0.83, 95% CI 0.30-1.36, P = 2.00×10-3) and type 2 diabetes (IVW: Beta = 0.53, 95% CI 0.16-0.90, P = 5.08×10-3).

Conclusion

This study affirms causal relationships between smoking and obstructive chronic bronchitis, cancer of the bronchus, peripheral vascular disease, emphysema, pneumococcal pneumonia, chronic airway obstruction, type 2 diabetes, in the European population. These findings highlight the broad health impacts of smoking and support smoking cessation efforts.

Unveiling the Long-Term Lung Consequences of Smoking and Tobacco Consumption: A Narrative Review

Smoking and tobacco use present significant public health challenges due to their association with high morbidity and mortality rates worldwide. Despite reductions in smoking rates in many developed countries, global tobacco consumption remains high, especially in developing regions. This review examines the chronic effects of smoking on the respiratory system, detailing the pathological changes in the lungs and the resultant respiratory illnesses such as chronic obstructive pulmonary disease and lung cancer. Additionally, the review explores the impact of smoking on other body systems, including cardiovascular, immune, gastrointestinal, nervous, and reproductive systems. The extensive health implications of smoking emphasize the need for comprehensive public health interventions to reduce tobacco use and mitigate its adverse effects on health.

Assessing the contribution of the chemical exposome to neurodegenerative disease

Over the past few decades, numerous environmental chemicals from solvents to pesticides have been suggested to be involved in the development and progression of neurodegenerative diseases. Most of the evidence has accumulated from occupational or cohort studies in humans or laboratory research in animal models, with a range of chemicals being implicated. What has been missing is a systematic approach analogous to genome-wide association studies, which have identified dozens of genes involved in Alzheimer's disease, Parkinson's disease and other neurodegenerative diseases. Fortunately, it is now possible to study hundreds to thousands of chemical features under the exposome framework. This Perspective explores how advances in mass spectrometry make it possible to generate exposomic data to complement genomic data and thereby better understand neurodegenerative diseases.

Global burden of stroke attributable to secondhand smoke in 204 countries and territories from 1990 to 2019: analysis of the global burden of disease study

BACKGROUND

Secondhand smoke (SHS) continues a significant public health concern globally. This study aimed to assess the global burden of stroke attributable to SHS exposure during 1990-2019.

METHODS

This analysis utilized data on stroke morbidity and mortality from the Global Burden of Disease (GBD) 2019 study covering 204 countries and territories. We estimated stroke burden indicators attributable to SHS exposure, including age-standardized mortality rate (ASMR) and age-standardized disability-adjusted life-year rate (ASDR), stratified by age, sex, region, and stroke subtype.

RESULTS

In 2019, global SHS exposure accounted for 2.01 [95% uncertainty interval (UI): 1.49-2.58] million stroke mortality. The ASMR and ASDR were 2.5 (95% UI: 1.9-3.2) and 61.5 (95% UI: 46-78.8) per 100,000 population, respectively. The disease burden was higher among women than men and higher among the elderly than younger populations. Intracerebral hemorrhage and ischemic stroke had a more significant burden than subarachnoid hemorrhage. From 1990 to 2019, the ASMR and ASDR declined [estimated annual percentage change: -2.08 (95% CI: -2.21% to -1.95%) and -2.08% (95% CI: -2.19% to -1.97%) for each], but the absolute number of mortalities increased along with population growth. Substantial disparities existed across regions and sociodemographic groups.

CONCLUSION

Despite declining ASMR and ASDR over time, the absolute number of stroke deaths attributable to SHS continued to rise globally, imposing a considerable stroke burden worldwide. These findings can inform targeted interventions and policies aimed at SHS control.

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.

Behavioral and Cognitive Performance Following Exposure to Second-Hand Smoke (SHS) from Tobacco Products Associated with Oxidative-Stress-Induced DNA Damage and Repair and Disruption of the Gut Microbiome

Exposure to second-hand Smoke (SHS) remains prevalent. The underlying mechanisms of how SHS affects the brain require elucidation. We tested the hypothesis that SHS inhalation drives changes in the gut microbiome, impacting behavioral and cognitive performance as well as neuropathology in two-month-old wild-type (WT) mice and mice expressing wild-type human tau, a genetic model pertinent to Alzheimer's disease mice, following chronic SHS exposure (10 months to ~30 mg/m3). SHS exposure impacted the composition of the gut microbiome as well as the biodiversity and evenness of the gut microbiome in a sex-dependent fashion. This variation in the composition and biodiversity of the gut microbiome is also associated with several measures of cognitive performance. These results support the hypothesis that the gut microbiome contributes to the effect of SHS exposure on cognition. The percentage of 8-OHdG-labeled cells in the CA1 region of the hippocampus was also associated with performance in the novel object recognition test, consistent with urine and serum levels of 8-OHdG serving as a biomarker of cognitive performance in humans. We also assessed the effects of SHS on the percentage of p21-labeled cells, an early cellular marker of senescence that is upregulated in bronchial cells after exposure to cigarette smoke. Nuclear staining of p21-labeled cells was more prominent in larger cells of the prefrontal cortex and CA1 hippocampal neurons of SHS-exposed mice than in sham-exposed mice, and there was a significantly greater percentage of labelled cells in the prefrontal cortex and CA1 region of the hippocampus of SHS than air-exposed mice, suggesting that exposure to SHS may result in accelerated brain aging through oxidative-stress-induced injury.

Secondhand smoke exposure is independently associated with stroke among non-smoking adults in West Africa

BACKGROUND

Stroke is a leading cause of disability and mortality worldwide, but little is known about the contribution of secondhand smoke exposure (SHSE) to stroke epidemiology among indigenous Africans.

OBJECTIVE

To evaluate the association of SHSE with stroke among indigenous Africans.

METHODS

We analyzed the relationship of SHSE with stroke among 2990 case-control pairs of adults who had never smoked (identified in the SIREN study) using conditional logistic regression at a two-sided P < 0.05.

RESULTS

Multivariable-adjusted odds ratio and 95% confidence interval; 1.25 (1.04, 1.50; P = 0.02) revealed SHSE was positively associated with stroke independent of stroke subtypes.

CONCLUSION

Culturally relevant primary prevention strategies targeted at SHSE might be promising in preventing stroke among Africans.

Novel Pharmacotherapies in Parkinson's Disease

Parkinson’s disease (PD), an age-related progressive neurodegenerative condition, is associated with loss of dopaminergic neurons in the substantia nigra pars compacta (SNpc), which results in motor deficits characterized by the following: akinesia, rigidity, resting tremor, and postural instability, as well as nonmotor symptoms such as emotional changes, particularly depression, cognitive impairment, gastrointestinal, and autonomic dysfunction. The most common treatment for PD is focused on dopamine (DA) replacement (e.g., levodopa = L-Dopa), which unfortunately losses its efficacy over months or years and can induce severe dyskinesia. Hence, more efficacious interventions without such adverse effects are urgently needed. In this review, following a general description of PD, potential novel therapeutic interventions for this devastating disease are examined. Specifically, the focus is on nicotine and nicotinic cholinergic system, as well as butyrate, a short chain fatty acid (SCFA), and fatty acid receptors.