Association between rosacea and smoking: A systematic review and meta-analysis

The relationship between smoking and rosacea: A Mendelian randomization study

BACKGROUND

Rosacea can be seen in many patients nowadays, and the related causes are complex. Despite a certain association between smoking and rosacea being reported by several studies, the actual causality has not been established for the possible bias and confounders.

METHODS

We used Mendelian randomization (MR) to evaluate a potential causal effect of smoking on rosacea risk. Statistics on smoking and rosacea were obtained from the FinnGen project and Neale Lab Consortium. The causal association was assessed by multiple methods including inverse variance weighted (IVW), MR Egger, weighted median, and weighted mode. Furthermore, sensitivity analyses were also conducted to address pleiotropy, along with the leave-one-out method.R version 4.2.3 was applied for the analyses.

RESULTS

The IVW estimation revealed that previous smoking has a deleterious effect on rosacea (odds ratio [OR] = 6.7729, 95% confidence interval [CI] = 1.5691-29.2356, p = 0.0104). By contrast, there was no statistically relationship between current smokers and rosacea (OR = 0.6180, 95% CI = 0.0605-6.3094, p = 0.6847). Results were similar in the analysis based on the weighted median method (previous smoking: OR = 8.6297, 95% CI = 1.0131-73.5071, p = 0.0486; current smoking: OR = 0.2896, 95% CI = 0.0106-7.9132, p = 0.4627). The stability of the causal effect estimates was supported by several sensitivity analyses and the leave-one-out method.

CONCLUSION

Our MR study found support forrosacea risk and previous smoking. Although no evidence was found to increase the risk of rosacea in current smokers, to prevent various diseases associated with smoking, the public should be encouraged to avoid smoking at the very beginning.

Correlation between cigarette smoking and alcohol consumption and Rosacea: A two-sample Mendelian randomization study

BACKGROUND

Controversy persists regarding the causal relationship between Cigarette smoking, alcohol consumption, and Rosacea. This paper employs the Mendelian randomization (MR) method to elucidate the correlation between Cigarette smoking, alcohol consumption, and Rosacea. The aim is to contribute valuable insights to aid in the prevention and early treatment of Rosacea.

METHOD

Summary datasets for cigarette smoking parameters (Cigarettes smoked per day, Smoking status: Previous, smoking status: Current) and alcohol consumption (Alcoholic drinks per week) were selected alongside data for Rosacea from genome-wide association studies (GWAS). The Two-sample MR method was employed to analyze the correlation between cigarette smoking, alcohol consumption, and Rosacea. Various MR analysis methods, including inverse variance weighting (IVW), MR-Egger, Simple Mode, Weighted Mode, and Weighted Median, were chosen. IVW served as the primary analysis method.

RESULTS

The results indicate a significant negative association between Cigarettes smoked per day and Rosacea. Moreover, a significant positive correlation was observed between Smoking status: Previous and Rosacea. However, no significant associations were found between Smoking status: Current, Alcoholic drinks per week, and Rosacea.

CONCLUSION

This study provides further clarity on the association between cigarette smoking, drinking, and Rosacea through a two-sample MR analysis. Notably, the number of cigarettes smoked per day appears to be associated with a reduced incidence of Rosacea, while cigarette smoking cessation may increase the risk. Surprisingly, alcohol consumption does not emerge as a significant risk factor for Rosacea. These findings contribute to a nuanced understanding of the complex relationship between lifestyle factors and the occurrence of Rosacea, offering potential insights for preventive measures and early intervention.

The impact of smoking and alcohol consumption on rosacea: a multivariable Mendelian randomization study

Backgrounds

Observational studies have shown that cigarette smoking is inversely associated with risk of rosacea, However, it remains uncertain whether this association is causal or it is a result of reverse causation, and whether this association is affected by drinking behaviors.

Methods

This study utilized the summary-level data from the largest genome-wide association study (GWAS) for smoking, alcohol consumption, and rosacea. The objective was to investigate the effect of genetically predicted exposures to smoking and alcohol consumption on the risk of developing rosacea. Two-sample bidirectional Mendelian randomization (MR) was applied, accompanied by sensitive analyses to validate the robustness of findings. Furthermore, multivariable MR was conducted to evaluate the direct impact of smoking on rosacea.

Results

A decreased risk of rosacea was observed in individuals with genetically predicted lifetime smoking [odds ratio (OR)MR - IVW = 0.53; 95% confidence interval (CI), 0.318-0.897; P = 0.017], and number of cigarettes per day (ORMR - IVW = 0.55; 95% CI, 0.358-0.845; P = 0.006). However, no significant associations were found between initiation of regular smoking, smoking cessation, smoking initiation, alcohol consumption and rosacea. Reverse MR analysis did not show any associations between genetic liability toward rosacea and smoking or alcohol drinking. Importantly, the effect of lifetime smoking and the number of cigarettes per day on rosacea remained significant even after adjusting for alcohol consumption in multivariable MR analysis.

Conclusion

Smoking was causally related to a lower risk of rosacea, while alcohol consumption does not appear to be associated with risk of rosacea.

Rosacea, microbiome and probiotics: the gut-skin axis

Rosacea is an inflammatory skin disease involving diverse symptoms with a variable clinical progress which can severely impact the patient's quality of life as well as their mental health. The pathophysiological model of rosacea involves an unbalanced immune system predisposed to excessive inflammation, in addition to vascular and nervous alterations, being certain cutaneous microorganisms' triggers of the symptoms onset. The gut-skin axis explains a bidirectional interaction between skin and gut microbiota in some inflammatory skin diseases such as atopic dermatitis, psoriasis, or rosacea. The introduction and consolidation of the next-generation sequencing in recent years has provided unprecedented information about the microbiome. However, the characterization of the gut and skin microbiota and the impact of the gut-skin axis in patients with rosacea has been little explored, in contrast to other inflammatory skin diseases such as atopic dermatitis or psoriasis. Furthermore, the clinical evolution of patients with rosacea is not always adequate and it is common for them to present a sustained symptomatology with frequent flare-ups. In this context, probiotic supplementation could improve the clinical evolution of these patients as happens in other pathologies. Through this review we aim to establish and compile the basics and directions of current knowledge to understand the mechanisms by which the microbiome influences the pathogenesis of rosacea, and how modulation of the skin and gut microbiota could benefit these patients.

Systematic replication of smoking disease associations using survey responses and EHR data in the All of Us Research Program

OBJECTIVE

The All of Us Research Program (All of Us) aims to recruit over a million participants to further precision medicine. Essential to the verification of biobanks is a replication of known associations to establish validity. Here, we evaluated how well All of Us data replicated known cigarette smoking associations.

MATERIALS AND METHODS

We defined smoking exposure as follows: (1) an EHR Smoking exposure that used International Classification of Disease codes; (2) participant provided information (PPI) Ever Smoking; and, (3) PPI Current Smoking, both from the lifestyle survey. We performed a phenome-wide association study (PheWAS) for each smoking exposure measurement type. For each, we compared the effect sizes derived from the PheWAS to published meta-analyses that studied cigarette smoking from PubMed. We defined two levels of replication of meta-analyses: (1) nominally replicated: which required agreement of direction of effect size, and (2) fully replicated: which required overlap of confidence intervals.

RESULTS

PheWASes with EHR Smoking, PPI Ever Smoking, and PPI Current Smoking revealed 736, 492, and 639 phenome-wide significant associations, respectively. We identified 165 meta-analyses representing 99 distinct phenotypes that could be matched to EHR phenotypes. At P < .05, 74 were nominally replicated and 55 were fully replicated. At P < 2.68 × 10-5 (Bonferroni threshold), 58 were nominally replicated and 40 were fully replicated.

DISCUSSION

Most phenotypes found in published meta-analyses associated with smoking were nominally replicated in All of Us. Both survey and EHR definitions for smoking produced similar results.

CONCLUSION

This study demonstrated the feasibility of studying common exposures using All of Us data.