Evaluation of the effect of smokeless tobacco (Maras powder) on choroidal and retinal blood flow: an optical coherence tomography angiography study

Does Maras powder affect the nasal mucociliary clearence?

PURPOSE

Many studies have been conducted about the effect of cigarettes and other tobacco products on mucociliary clearance. However, there has been no study of the relationship between mucociliary clearance and Maras powder, which is a smokeless tobacco product. The aim of this study was to evaluate the effect of Maras powder use on mucociliary clearance through comparisons with cigarette smokers and those who used no tobacco products.

METHODS

The study included 75 male volunteers, aged 23-54 years. Group 1 (n: 25) comprised subjects who do not use any tobacco products, Group 2 (n: 25) those who smoked cigarettes, and Group 3 (n: 25) those who used Maraş powder. The saccharin test was used to evaluate mucociliary clearance and the time was recorded in seconds. The groups were statistically compared in respect of mean age and mucociliary clearance time (MCCT).

RESULTS

The mean MCCT was determined to be 645.8 ± 200 secs for the whole study sample, 497 ± 108 secs for Group 1, 796 ± 200 secs for Group 2, and 644 ± 161 secs for Group 3. The difference between the groups in respect of MCCT was statistically significant (p < 0.001). No statistically significant difference was determined between the groups in respect of mean age (p = 0.730).

CONCLUSION

The study results demonstrated that the nasal mucociliary clearance time was prolonged both by cigarettes and by the use of Maras powder, and that this time was prolonged more by cigarette smoking than the use of Maras powder.

Association of cigarette smoking with retinal capillary plexus: an optical coherence tomography angiography study

PURPOSE

To investigate the association between cigarette smoking and retinal capillary plexus (RCP) using optical coherence tomography angiography (OCTA) and to examine whether potential vascular risk factors could impact their association.

METHODS

This is a cross-sectional, community-based study. The Jidong Eye Cohort Study included participants aged ≥18 years in the Jidong community (Tangshan city, northern China) from August 2019 to January 2020. All participants underwent comprehensive ophthalmic examination and completed detailed smoking questionnaires. Retinal vessel density in the superficial and deep RCP was automatically measured using OCTA.

RESULTS

Of the 2598 participants included in the study, 2026 (78.0%) never smoked and 572 (22.0%) had a history of smoking (494 [19.0%] current smokers and 78 [3.0%] former smokers). The median (interquartile range) age was 41 (34-52) years for the non-smoking group and 45 (35-54.5) years for the smoking group. Multivariable analysis showed that smoking history is associated with a low deep RCP vessel density in the parafovea (β, -0.53; 95% confidence interval [CI], -0.82 to -0.24) and four quadrants. Increased smoking pack-years were associated with reduced deep RCP vessel density in the parafovea (p for trend <0.001) and four quadrants. The significant interaction between diabetes and smoking only was found for superficial RCP vessel density in the parafovea (p for interaction = 0.014) and four quadrants except for the temporal quadrants.

CONCLUSIONS

Cigarette smoking is an independent risk factor for reduced deep RCP vessel density. Our findings imply the potential detrimental effect of smoking on the occurrence of ocular diseases.