Cigarette smoking and glaucoma in the United States population

Smoking Intensity is Associated With Progressive Optic Nerve Head Vessel Density Loss in Glaucoma

PRCIS

A lifetime history of greater smoking consumption was associated with faster vessel density loss over time. Smoking intensity should be considered when assessing the risk of glaucoma progression, as well as its management.

PURPOSE

To investigate the relationship of smoking and smoking intensity, with the rate of optic nerve head (ONH) whole image capillary density (wiCD) loss in primary open angle glaucoma (POAG) and glaucoma suspect patients.

METHODS

In this longitudinal study, patients with POAG who had at least 2 years of follow-up and optical coherence tomography angiography (OCTA) performed at a minimum of 4 visits were selected for study. The smoking intensity was calculated as the pack-year at the baseline OCTA. Univariable and multivariable linear mixed models were used to determine the effect of each parameter on the rates of wiCD loss over time. Nonlinear least-squares estimation with piecewise regression model was used to investigate the cutoff point for the relationship between wiCD loss and smoking intensity.

RESULTS

One hundred sixty-four eyes (69 glaucoma suspect and 95 POAG) of 110 patients were included with a mean (95% CI) follow-up of 4.0 (3.9 to 4.1) years. Of the 110 patients, 50 (45.5%) had a reported history of smoking. Greater smoking intensity was associated with faster wiCD loss [-0.11 (-0.23 to 0.00)] %/year per 10 pack-year higher; P =0.048) after adjusting for covariates. The wiCD thinning became significantly faster when smoking intensity was greater than 22.2 pack-years. Smoking had no effect on the rate of wiCD thinning in patients who smoked <22.2 pack-years during their lifetime.

CONCLUSIONS

A history of greater smoking consumption was associated with faster vessel density loss, suggesting smoking intensity as a potential risk factor for glaucoma.

Migraine headache and other risk factors associated with glaucoma among the adult population living in Armenia: a case-control study

PURPOSE

This study aimed to assess the association between migraine headache and glaucoma among the adult population living in Armenia.

METHODS

This case-control study recruited 145 cases with glaucoma and 250 controls without glaucoma and other ocular disorders except refractive error from Optomed Canada Diagnostic Eye Center in Armenia. A structured questionnaire contained questions on socio-demographics, family history of glaucoma and stroke, ocular health, smoking, migraine, and obstructive sleep apnea. The Migraine Screening Questionnaire assessed possible migraine and the Berlin Questionnaire measured obstructive sleep apnea.

RESULTS

The mean ages of cases and controls were 63.3 (SD = 12.3) and 39.5 (SD = 13.5), respectively. Females comprised 62.8% of cases and 69.1% of controls. A total of 17.8% of cases and 19.0% of controls had possible migraine. In the adjusted analysis older age (OR 1.17; 95% CI 1.12; 1.23), average/lower than average socio-economic status (OR 5.27; 95% CI 1.30; 21.3), and family history of glaucoma (OR 4.25; 95% CI 1.51; 11.9) were associated with high-tension glaucoma.

CONCLUSION

Timely case detection of glaucoma among those with average/low socio-economic status and those with family history of glaucoma could prevent further progression of the disease. Further studies to explore the relationship between migraine headache and specific types of glaucoma may be worthwhile.

Impact of smoking on glaucoma

PURPOSE OF REVIEW

Assessing whether lifestyle related factors play a role in causing primary open-angle glaucoma (POAG) is of great value to clinicians, public health experts and policy makers. Smoking is a major global public health concern and contributes to ocular diseases such as cataracts, and age-related macular degeneration through ischemic and oxidative mechanisms. Recently, smoking has been investigated as a modifiable risk factor for glaucoma. In the presence of an association with glaucoma, provision of advice and information regarding smoking to patients may help reduce the burden of disease caused by POAG. Therefore, the aim of this review is to summarize the current evidence regarding the effect of smoking in the pathogenesis of glaucoma and its incidence, progression as well as the benefits of smoking cessation.

RECENT FINDINGS

While the association between glaucoma development and smoking history is controversial, in the last decade, several recent studies have helped to identify possible effects of smoking, especially heavy smoking, in regard to glaucomatous progression. Smoking cessation may possibly be protective against glaucoma progression.

SUMMARY

Smoking may play a role in glaucoma progression and long-term smoking cessation may be associated with lower glaucoma progression. The dose-response relationship between smoking and glaucoma as well as therapeutic potential of smoking cessation needs to be further validated with both preclinical and rigorous clinical studies.

Former smoking as a risk factor for visual field progression in exfoliation glaucoma patients in Sweden

PURPOSE

The present study aimed to identify whether former smoking was a risk factor for visual field progression in exfoliation glaucoma patients.

METHODS

Prospective nonrandomised cohort study. The study included patients diagnosed with exfoliation glaucoma. All included patients were followed for three years (± three months) with reliable visual fields. At least five reliable visual fields needed to be included in the study. Exfoliation glaucoma was defined using the European Glaucoma Society Guidelines. The visual fields were tested using the 24-2 test strategy of the Humphrey Field Analyzer. Smoking was assessed through questionnaires. Outcomes: Visual field progression. Three different approaches were used: difference in mean deviation (MD), rate of progression (ROP), and guided progression analysis (GPA).

RESULTS

In total, n = 113 patients were included; among them, n = 57 were smokers. Smoking was a significant predictor for visual field progression in the three models (MD/ROP/GPA) studied (p = 0.01/p = 0.001/p ≤ 0.001), even adjusting for intraocular pressure (IOP). Other predictors were included in the MD model: IOP at diagnosis (p = 0.04) and selective laser trabeculoplasty (SLT) treatment (p = 0.01). Other predictors were in the ROP model: Visual field index (p = 0.005), number of medications (p = 0.001) and SLT treatment (p = 0.001). The number of medications was another predictor in the GPA model (p = 0.002).

CONCLUSIONS

Former smoking induced visual field deterioration in all models studied. Smoking status should be considered when establishing the glaucoma diagnosis. Increased glaucoma care should be provided to former smokers to slow the progression of the disease.

Smoking and progressive retinal nerve fibre layer thinning in glaucoma

BACKGROUND/AIMS

To investigate the relationship between smoking and smoking intensity, and the rate of retinal nerve fibre layer (RNFL) thinning in patients with primary open angle glaucoma (POAG).

METHODS

In this longitudinal study, patients with POAG who had at least 3 years of follow-up with a minimum of 5 visits of optical coherence tomography (OCT) were enrolled. The smoking intensity was calculated as the pack-year at the baseline OCT. Univariable and multivariable linear mixed models were used to determine the effect of each parameter on the rates of RNFL thinning over time. Non-linear least-squares estimation with piecewise regression model was used to investigate the cut-off point for the relationship between circumpapillary RNFL thinning and smoking intensity.

RESULTS

A total of 466 eyes of 314 patients were included over the mean (95% CI) follow-up of 6.6 (6.4 to 6.7) years. Of the 314 patients, 121 (39%) had reported any history of smoking. Greater smoking intensity was associated with faster RNFL thinning (-0.06 (95% CI -0.11 to 0.00) µm/year per 10 pack-year higher; p=0.031) after adjusted for confounding factors. RNFL thinning became significantly faster when smoking intensity was >8 pack-year.

CONCLUSIONS

Smoking intensity is associated with faster rates of RNFL thinning. Evaluation of smoking intensity might add information to the assessment of risk of glaucoma progression. Future studies are required to explore if withdrawing smoking as a modifiable risk factor can decrease progression in patients with glaucoma.

Association between lifestyle habits and glaucoma incidence: a retrospective cohort study

BACKGROUND/OBJECTIVES

Although lifestyle habits may represent modifiable risk factors of glaucoma, the association between lifestyle factors and glaucoma is not well understood. The aim of this study was to investigate the association between lifestyle habits and the development of glaucoma.

SUBJECTS/METHODS

Participants who underwent health check-ups from 2005 to 2020 using a large-scale administrative claims database in Japan were included in the study. Cox regression analyses were performed where glaucoma development was regressed on the lifestyle (body mass index, current smoking, frequency and amount of alcohol consumption, eating habits, exercise habits and quality of sleep), age, sex, hypertension, diabetes mellitus and dyslipidaemia.

RESULTS

Among the 3,110,743 eligible individuals, 39,975 developed glaucoma during the mean follow-up of 2058 days. Factors associated with increased risk of glaucoma were overweight/obese (vs. moderate weight: hazard ratio, 1.04 [95% confidence interval, 1.02-1.07]), alcohol consumption of 2.5-4.9 units/day, 5-7.4 units/day, and ≥7.5 units/day (vs. <2.5 units/day: 1.05 [1.02-1.08], 1.05 [1.01-1.08] and 1.06 [1.01-1.12], respectively), skipping breakfast (1.14 [1.10-1.17]), late dinner (1.05 [1.03-1.08]) and daily walking of 1 h (1.14 [1.11-1.16]). Factors associated with decreased risk of glaucoma were daily alcohol consumption (vs. rarely: 0.94 [0.91-0.97]) and regular exercise (0.92 [0.90-0.95]).

CONCLUSIONS

Moderate body mass index, having breakfast, avoiding late dinner, limiting alcohol intake to <2.5 units/day, and regular exercise were associated with a reduced risk of developing glaucoma in the Japanese population. These findings may be useful for promoting glaucoma prophylaxis.

Impact of smoking on choroidal microvasculature dropout in glaucoma: a cross-sectional study

OBJECTIVE

To investigate the effect of smoking on choroidal microvasculature dropout (MvD) in glaucoma.

DESIGN

Cross-sectional study.

SETTING

Tertiary glaucoma centre.

PARTICIPANTS

223 eyes of 163 patients with primary open-angle glaucoma who had undergone imaging with optical coherence tomography angiography and completed a questionnaire on smoking from the Diagnostic Innovations in Glaucoma Study.

PRIMARY OUTCOME MEASURES

Linear mixed-effects models were used to determine the effect of each parameter on MvD area and angular circumference. The sensitivity analysis was performed by categorising the glaucoma severity determined by visual field mean deviation (MD).

RESULTS

MvD was found in 37 (51.4%) eyes with smoking history and in 67 (44.4%) eyes with non-smokers (p=0.389). Larger MvD area and wider angular circumference were found in smokers compared with non-smokers (p=0.068 and p=0.046, respectively). In a multivariable model, smoking intensity was significantly associated with MvD area (0.30(95% CI 0.01 to 0.60) each 0.01 mm2 per 10 pack-years; p=0.044). In eyes with moderate-severe glaucoma (MD <-6), smoking intensity was associated with larger MvD area (0.47 (95% CI 0.11 to 0.83) each 0.01 mm2 per 10 pack-years; p=0.011), whereas no significant association was found in early glaucoma (MD ≥-6) (-0.08 (95% CI -0.26 to 0.11), p=0.401).

CONCLUSIONS

Smoking intensity was associated with larger choroidal MvD area in eyes with glaucoma, especially in patients with more severe disease.

TRIAL REGISTRATION NUMBER

NCT00221897.

Genetic Associations Between Smoking- and Glaucoma-Related Traits

Purpose

The purpose of this study was to describe the genetic relationship between smoking and glaucoma.

Methods

We used summary-level genetic data for smoking initiation, smoking intensity (cigarettes per day [CPD]), intraocular pressure (IOP), vertical cup-disc ratio, and open-angle glaucoma (OAG) to estimate global genetic correlations (rg) and perform two-sample Mendelian randomization (MR) experiments that explored relations between traits. Finally, we examined associations between smoking genetic risk scores (GRS) and smoking traits with measured IOP and OAG in Rotterdam Study participants.

Results

We identified weak inverse rg between smoking- and glaucoma-related traits that were insignificant after Bonferroni correction. However, MR analysis revealed that genetically predicted smoking initiation was associated with lower IOP (-0.18 mm Hg per SD, 95% confidence interval [CI] = -0.30 to -0.06, P = 0.003). Furthermore, genetically predicted smoking intensity was associated with decreased OAG risk (odds ratio [OR] = 0.74 per SD, 95% CI = 0.61 to 0.90, P = 0.002). In the Rotterdam Study, the smoking initiation GRS was associated with lower IOP (-0.09 mm Hg per SD, 95% CI = -0.17 to -0.01, P = 0.04) and lower odds of OAG (OR = 0.84 per SD, 95% CI = 0.73 to 0.98, P = 0.02) in multivariable-adjusted analyses. In contrast, neither smoking history nor CPD was associated with IOP (P ≥ 0.38) or OAG (P ≥ 0.54). Associations between the smoking intensity GRS and glaucoma traits were null (P ≥ 0.13).

Conclusions

MR experiments and GRS generated from Rotterdam Study participants support an inverse relationship between smoking and glaucoma.

Translational Relevance

Understanding the genetic drivers of the inverse relationship between smoking and glaucoma could yield new insights into glaucoma pathophysiology.

The effect of body mass index reduction on intraocular pressure in a large prospective cohort of apparently healthy individuals in Israel

PURPOSE

To investigate the effect of change in body mass index (BMI) on intraocular pressure (IOP) in a large cohort of apparently healthy volunteers who underwent an annual comprehensive screening examinations.

METHODS

This study included individuals who were enrolled in the Tel Aviv Medical Center Inflammation Survey (TAMCIS) and had IOP and BMI measurements at their baseline and follow up visits. Relationships between BMI and IOP and the effect of change in BMI on IOP were investigated.

RESULTS

A total of 7,782 individuals had at least one IOP measurement at their baseline visit, and 2,985 individuals had ≥2 visits recorded. The mean (SD) IOP (right eye) was 14.6 (2.5) mm Hg and mean (SD) BMI was 26.4 (4.1) kg/m2. IOP positively correlated with BMI levels (r = 0.16, p<0.0001). For individuals with morbid obesity (BMI≥35 kg/m2) and ≥2 visits, a change in BMI between the baseline and first follow-up visits correlated positively with a change in the IOP (r = 0.23, p = 0.029). Subgroup analysis of subjects who had a reduction of at least 2 BMI units showed a stronger positive correlation between change in BMI and change in IOP (r = 0.29, p<0.0001). For this subgroup, a reduction of 2.86 kg/m2 of BMI was associated with a reduction of 1 mm Hg in IOP.

CONCLUSIONS

BMI loss correlated with reduction in IOP, and this correlation was more pronounced among morbidly obese individuals.

Impact of Smoking on Visual Field Progression in a Long-term Clinical Follow-up

PURPOSE

To investigate the effect of smoking on rates of progressive visual field (VF) damage over time in glaucoma.

DESIGN

Retrospective cohort study.

PARTICIPANTS

Five hundred eleven eyes of 354 patients with glaucoma followed up from multicenter glaucoma registries.

METHODS

In this longitudinal study, 354 patients with primary open-angle glaucoma with a minimum of 3 years of follow-up and 5 VF tests were enrolled from the Diagnostic Innovations in Glaucoma Study and the African Descent and Glaucoma Evaluation Study. Univariate and multivariate linear mixed models were used to investigate the effects of smoking on rates of 24-2 VF mean deviation loss. Visual field progression was defined using pointwise linear and significant negative VF mean deviation loss. Logistic regression was used to identify baseline factors and whether different levels of smoking intensity were associated with VF progression. Kaplan-Meier survival analysis and the log-rank test were used to compare the cumulative risk ratio of progression between smoker and never smoker groups.

MAIN OUTCOME MEASURES

Visual field progression.

RESULTS

Five hundred eleven eyes of 354 patients were included over the median follow-up of 12.5 years. Median baseline age was 64.8 years. Of the 354 patients, 124 (35%) were Black, and 149 (42.1%) and 168 (59.8%) had reported a history of smoking or alcohol consumption, respectively. In a multivariate model, higher smoking intensity was associated with faster VF loss (coefficient, -0.05 decibels (dB)/year per 10 pack-years; 95% confidence interval [CI], -0.08 to -0.01 dB/year per 10 pack-years; P = 0.010). Developing VF progression in eyes of heavy smokers (≥ 20 pack-years) was 2.2 times more than in eyes of patients without smoking history (odds ratio, 2.21; 95% CI, 1.02-4.76; P = 0.044). Statistically significant differences were found between heavy smokers (≥ 20 pack-years) and never smokers by Kaplan-Meier analysis (P = 0.011, log-rank test).

CONCLUSIONS

Heavy smokers are more likely to sustain VF loss in eyes with glaucoma. The prospective longitudinal design of this study supports the hypothesis that levels of smoking may be a significant predictor for glaucoma progression. Additionally, this information can be used for clinically relevant tobacco prevention and intervention messages.

Smoking Cessation May Reduce Risk of Visual Field Progression in Heavy Smokers

PRCIS

The earlier a person quits smoking the more likely is the optic nerve be spared from damage.

PURPOSE

To investigate the effect of smoking cessation on visual field (VF) progression in glaucoma.

METHODS

Primary open angle glaucoma patients with a minimum of 3 years follow-up and 5 VFs were included. Linear mixed models were used to investigate the effects of smoking on the rates of 24-2 VF mean deviation loss after adjusting for confounding factors. Cox proportional hazard regression was used to identify whether different levels of smoking intensity were associated with VF progression with respect to different duration of quitting.

RESULTS

Five hundred eleven eyes of 354 patients were included over the mean follow-up of 12.4 years. Mean baseline age (95% confidence interval) was 62.3 (61.2, 63.4) years. One hundred forty nine (42.1%) patients were smokers. In a multivariable model, smoking intensity was associated with faster VF loss (-0.06, 95% confidence interval (-0.10, -0.01) dB/year per 10 pack-years, P =0.01) among smokers. Heavy smokers (≥20 pack-years) who had quit ˂25 years prior had significantly greater odds of VF progression compared with never smokers (odds ratio=2.49 (1.01, 6.08); P =0.046). There was no significant difference in odds of VF progression in heavy smokers who had quit smoking more than 25 years compared with never smokers ( P =0.43). A significantly higher proportion of VF progression was found in heavy smokers who quit < 25 years compared with heavy smokers who quit ≥25 years by Kaplan-Meier analysis ( P =<0.001).

CONCLUSIONS

After ≥25 years of smoking cessation, the risk of VF progression in former heavy smokers becomes similar to never smokers. Long-term smoking cessation may be associated with lower VF progression in glaucoma patients.

Effects of Smoking on Optic Nerve Head Microvasculature Density in Glaucoma

PRCIS

Decreased superficial whole image capillary density was observed in open angle glaucoma (OAG) patients with high smoking intensity.

PURPOSE

To investigate the effects of smoking on optic nerve head capillary density measured by optical coherence tomography angiography in patients with OAG.

METHODS

In this retrospective cross-sectional study, perimetric and preperimetric glaucoma patients enrolled in the Diagnostic Innovations in Glaucoma Study (DIGS) with optical coherence tomography angiography follow-up were included. Univariable and multivariable linear mixed analysis were performed to determine the effects of different variables on the superficial whole image capillary density.

RESULTS

A total of 432 eyes of 271 glaucoma patients comprising 63 preperimetric (106 eyes) and 208 perimetric OAG (326 eyes) were included. A history of tobacco consumption was reported in 105 (38.8%). Among smokers, mean (95% confidence interval) smoking intensity was 12.8 (10.2, 15.5) pack-years. After adjusting for age, glaucoma severity and other confounders, each 10 pack-year increase in smoking intensity (95% confidence interval) was associated with -0.54 (-1.06, -0.02) % lower whole image capillary density ( P =0.041).

CONCLUSIONS

Smoking intensity is associated with reduced optic nerve vessel density in glaucoma.

Prevalence of Primary Open-Angle Glaucoma and its Relationship with Smoking in the Population of the Azar Cohort: A Cross-Sectional Study

PURPOSE

The purpose is to determine the prevalence of primary open-angle glaucoma (POAG) and study the relationship of smoking and other potential risk factors with POAG.

METHODS

This is a cross-sectional study based on the Azar cohort databases (including the eye cohort study) in Iran, including 11,208 participants aged 35-70 years. According to the questionnaire, participants were divided into five groups in terms of smoking. Ophthalmologic examinations were performed in two steps. The first step was performed by an optometrist, and all referred participants underwent a complete ophthalmological examination in the second step, then after POAG cases were diagnosed using Criteria of the International Society of Geographic and Epidemiological Ophthalmology.

RESULTS

Of the participants, 4992 (44.5%) were male and 6216 (55.5%) were female, with a mean age of 50.1 ± 9.27 years. The prevalence of POAG in our study population was 1%, which included 58 (1.2%) males and 58 (0.9%) females. There was no significant difference between the two groups in terms of the prevalence of different smoking categories in both genders. There was a statistically significant difference between the two groups in both genders in terms of diabetes mellitus (DM) after adjusting for age and there was a statistically significant difference between the two groups in the male population in terms of triglycerides ≥150 mg/dl.

CONCLUSION

Findings of this study indicated that there is no association between cigarette smoking in different doses and a history of smoking with POAG. Other factors, such as aging and underlying diseases, including DM and hypertriglyceridemia, have a statistically significant association with POAG.

Association Between E-Cigarette Use and Visual Impairment in the United States

PURPOSE

To determine whether there is an association between e-cigarette use and visual impairment in the United States adult population.

DESIGN

Cross-sectional.

METHODS

In this population survey study, we reviewed 1,173,646 adults ≥18 years of age from all 50 United States and 3 U.S. territories with self-reported responses to the Center for Disease Control and Prevention's 2016-2018 Behavioral Risk Factor Surveillance System (BRFSS) annual telephone survey. We reviewed e-cigarette use (current, former, or never), as assessed by the questions: "Have you ever used an e-cigarette or other electronic vaping product, even just one time, in your entire life?" and "Do you now use e-cigarettes or other electronic vaping products every day, some days, or not at all?" The primary outcome measure was visual impairment, defined as a binary outcome "yes" or "no" to the question, "Are you blind or do you have serious difficulty seeing, even when wearing glasses?"

RESULTS

After excluding missing data, there were 1,173,646 participants. The adjusted odds ratio of visual impairment in current e-cigarette users compared with never e-cigarette users was 1.34 (95% confidence interval [CI] 1.20-1.48), and in former e-cigarette users was 1.14 (95% CI 1.06-1.22). In the subgroup of 662,033 never users of traditional cigarettes (weighted 59.6% of study population), the adjusted odds ratio of visual impairment in current e-cigarette users compared with never e-cigarette users was 1.96 (95% CI 1.48-2.61) and in former e-cigarette users was 1.02 (95% CI 0.89-1.18).

CONCLUSIONS

Current compared with never e-cigarette usage was associated with a higher odds of visual impairment in the BRFSS 2016-2018 population, independent of traditional cigarette use.

Role of Oxidative Stress in Retinal Disease and the Early Intervention Strategies: A Review

The retina, owing to its cellular anatomy and physical location, is susceptible to generating reactive oxygen species (ROS), which are associated with several major retinal diseases. When ROS exceeds the body's natural antioxidants, the retina is in a state of oxidative stress, which is recognized as the pathogenesis of retinal diseases. The early stage of the pathogenic process is an adaptive change in which oxidative stress and endogenous defense mechanisms occur. If no treatment is applied, the retinal diseases will progress to the pathological stage with neuronal and vascular dysfunction or damage and even blindness. This review summarizes the role of oxidative stress in several common retinal diseases, including retinitis pigmentosa, age-related macular degeneration, diabetic retinopathy, glaucoma, and retinopathy of prematurity. In addition, we discuss the early intervention strategies for these diseases. An outline is provided to identify potential intervention targets for further research. Early intervention for retinal diseases is necessary and urgent and may offer hope to improve patients' quality of life through functional vision.

Maternal smoking during pregnancy and long-term ophthalmic morbidity of the offspring

OBJECTIVE

To examine whether smoking during pregnancy is correlated with long-term ophthalmic complications of the offspring.

STUDY DESIGN

A population-based cohort analysis was performed comparing all deliveries of mothers who reported smoking during pregnancy and non-smoking mothers between 1991 and 2014 at a single tertiary medical center. Hospitalizations of the offspring up to the age of 18 years involving ophthalmic morbidities were evaluated according to a predefined set of ICD-9 codes. A Kaplan-Meier curve was used to compare cumulative hospitalization rate in exposed and unexposed offspring and a Cox proportional hazards model was used to control for confounders.

RESULTS

During the study period, 243,680 deliveries met the inclusion criteria. Of them, 2965 (1.2%) were children of smoking mothers. Ophthalmic-related hospitalizations were significantly higher in children born to smoking mothers, as compared with the non-smoking group (1.4% vs. 0.1%, p < 0.01). Specifically, these hospitalizations were due to higher rates of visual disturbance rate and ophthalmic infections. The Kaplan-Meier curve demonstrated a significant higher cumulative incidence of ophthalmic-related hospitalizations in the smoking group (log rank p < 0.001). Using a Cox proportional hazards model, controlling for potential confounders, maternal tobacco use was found to be independently associated with long-term ophthalmic morbidity of the offspring (adjusted HR = 1.51, CI 1.11-2.04).

CONCLUSION

Maternal smoking during pregnancy is an independent risk factor for long-term ophthalmic morbidity of the offspring. These results are in line with many recent studies that strongly support maternal smoking cessation during pregnancy due to high offspring morbidity risk.

Evaluation of subclinical alterations in retinal layers and microvascular structures with OCT and OCTA in healthy young short-term smokers

PURPOSE

To detect the changes that can be determined with optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA) in young and short-term smokers.

METHOD

In this cross-sectional, observational, and comparative study, 45 "healthy" smokers and 45 healthy non-smoker control participants were included. Those with a smoking history between 1 year to 5 years and an average of 10-30 cigarettes per day were included in the study. OCT and OCTA measurements were made at least 60 min after smoking and at least 8 h after caffeine-containing beverages in order to end the effect of nicotine on systemic and retinal blood flow in the smoking group.

RESULTS

The mean smoking period was 2.2 ± 0.13 years. Mean macular thickness(MMT), retinal nerve fiber layer(RNFL), and choroidal thickness(Cht) were significantly lower in the smoker group, while ganglion cell-inner plexiform layer(GC-IPL) thickness was higher. Vessel density(VD) values were similar between groups, while perfusion density(PD) values were significantly higher in the smoker group. There were significant correlations between MMT and outer VD, outer PD, foveal avascular zone(FAZ) perimeter and circularity index. FAZ area and central VD and PD were inversely correlated. Also, FAZ circularity index and subfoveal, nasal, and temporal ChTs were positively correlated.

CONCLUSION

Despite the short-term smoking, ischemic effects were observed in retinochoroidal and vascular structures.

Association of Secondhand Smoking Exposure With Choroidal Thinning in Children Aged 6 to 8 Years: The Hong Kong Children Eye Study

Importance

Secondhand smoking is a risk to adult ocular health, but its effect on children's ocular development is not known.

Objective

To assess the association between choroidal thickness and secondhand smoking exposure in children.

Design, Setting, and Participants

Children aged 6 to 8 years were consecutively recruited from January 2016 to July 2017 from the population-based Hong Kong Children Eye Study at the Chinese University of Hong Kong Eye Centre. All participants underwent detailed ophthalmic investigations. Choroidal thickness was measured by swept-source optical coherence tomography, with built-in software that automatically segmented the choroid layer to analyze its terrain imagery. History of secondhand smoking was obtained from a questionnaire. Multiple linear regression analyses were performed to assess the correlation between choroidal thickness and secondhand exposure when controlling for confounding factors. Analysis began July 2018 and ended in April 2019.

Main Outcomes and Measurements

The association between children's choroidal thickness and their exposure to secondhand smoking.

Results

Of 1400 children, 941 (67.2%) had no exposure to secondhand smoking, and 459 (32.8%) had exposure to secondhand smoking. The mean (SD) age was 7.65 (1.09) years for children in the nonexposure group and 7.54 (1.11) years for children in the exposure group. After adjustment for age, sex, body mass index, axial length, and birth weight, exposure to secondhand smoking was associated with a thinner choroid by 8.3 μm in the central subfield, 7.2 μm in the inner inferior, 6.4 μm in the outer inferior, 6.4 μm in the inner temporal, and 7.3 μm in the outer temporal. Choroidal thinning with also associated with increased number of family smokers and increased quantity of secondhand smoking. An increase of 1 family smoker was associated with choroidal thinning by 7.86 μm in the central subfield, 4.51 μm in the outer superior, 6.23 μm in the inner inferior, 5.59 μm in the outer inferior, 6.06 μm in the inner nasal, and 6.55 μm in the outer nasal. An increase of exposure to 1 secondhand cigarette smoke per day was associated with choroidal thinning by 0.54 μm in the central subfield, 0.42 μm in the inner temporal, and 0.47 μm in the outer temporal.

Conclusions and Relevance

This investigation showed that exposure to secondhand smoking in children was associated with choroidal thinning along with a dose-dependent effect. These results support evidence regarding the potential hazards of secondhand smoking to children.

Exposure to Secondhand Smoke in Children is Associated with a Thinner Retinal Nerve Fiber Layer: The Hong Kong Children Eye Study

PURPOSE

We sought to assess the effects of exposure to secondhand smoke (SHS) on peripapillary retinal nerve fiber layer (p-RNFL) thickness in children.

DESIGN

Cross-sectional study.

METHODS

Children 6-8 years of age were consecutively recruited from the population-based Hong Kong Children Eye Study. All participants received comprehensive ophthalmic examinations and p-RNFL thickness was measured by spectral-domain optical coherence tomography. SHS data were derived from a validated questionnaire. Associations between p-RNFL thickness and SHS exposure status, number of smokers in the family, and quantity of smoking in the family were determined by multivariate linear regression after adjusting for potential confounders.

RESULTS

Among the Hong Kong Children Eye Study cohort (n = 3,103), approximately one-third of children were exposed to SHS (35.4%, n = 1,097). Compared to those without exposure to SHS, children exposed to SHS had similar age (P = .83), gender (P = .17), body mass index (P = .44), birth weight (P = .23), and axial length (P = .34), but had lower family income (P < .001) and lower parental education level (P < .001). After adjusting for all the above factors, exposure to SHS was associated with a thinner global p-RNFL by 4.4 μm (P < .001). Reduced p-RNFL was also associated with increased numbers of smokers in the family (β = -3.40, P < .001) and increased quantity of SHS (β = -0.22, P < .001).

CONCLUSIONS

Exposure to SHS in children was associated with a thinner p-RNFL. A thinner p-RNFL may increase the risk of irreversible visual impairment in the future. Our results provide evidence to recommend that children avoid exposure to SHS.

Risk of cancer in patients with glaucoma: A nationwide population-based cohort study

To compare the risk of cancer development between patients with glaucoma and those without, we conducted a nationwide population-based cohort study using the Korean National Health Insurance Database. Individuals with diagnosis of glaucoma between 2007 and 2016 were identified, and controls were 1:1 matched based on age and sex. We calculated the incidence rates(IR) and hazard ratios(HR) before and after adjusting for age, gender, diabetes, smoking history, and body mass index. A total of 107,536 individuals with glaucoma and the same number of individuals without glaucoma were included. The IR of overall cancer were 12.23 and 11.62 per 1,000 individuals in the glaucoma and control groups, respectively. The HR of overall cancer was significantly higher in the glaucoma group before(HR: 1.053) and after adjusting for confounding factors(adjusted HR: 1.049) compared to that in the control group. The risk of overall cancer and specific cancers varied depending on gender and age groups, and the association was stronger in women and those under 65 years of age. Our study revealed that individuals with glaucoma showed higher risk of overall cancer and higher risk of specific cancers than those without glaucoma.

Smoking Is Associated with Higher Intraocular Pressure Regardless of Glaucoma: A Retrospective Study of 12.5 Million Patients Using the Intelligent Research in Sight (IRIS®) Registry

PURPOSE

To compare the average intraocular pressure (IOP) among smokers, past smokers, and never smokers using the American Academy of Ophthalmology Intelligent Research in Sight (IRIS®) Registry.

DESIGN

Retrospective database study of the IRIS® Registry data.

PARTICIPANTS

Intelligent Research in Sight Registry patients who were seen by an eye care provider during 2017.

METHODS

Patients were divided into current smoker, past smoker, and never smoker categories. The IOP was based on an average measurement, and separate analyses were performed in patients with and without a glaucoma diagnosis based on International Classification of Diseases (Ninth Edition and Tenth Edition) codes. Stratified, descriptive statistics by glaucoma status were determined, and the relationship between smoking and IOP was assessed with a multivariate linear regression model.

MAIN OUTCOME MEASURES

Mean IOP.

RESULTS

A total of 12 535 013 patients were included. Compared with never smokers, current and past smokers showed a statistically significantly higher IOP by 0.92 mmHg (95% confidence interval [CI], 0.88-0.95 mmHg) and 0.77 mmHg (95% CI, 0.75-0.79 mmHg), respectively, after adjusting for age, gender, glaucoma, age-related macular degeneration, diabetic retinopathy, cataract, glaucoma surgery, cataract surgery, and first-order interactions. In addition, the difference in IOP between current and never smokers was the highest in the fourth decade, regardless of the glaucoma status (glaucoma group, 1.14 mmHg [95% CI, 1.00-1.29 mmHg]; without glaucoma group, 0.68 mmHg [95% CI, 0.65-0.71 mmHg]).

CONCLUSIONS

Current smokers and past smokers have higher IOP than patients who never smoked. This difference is higher in patients with an underlying glaucoma diagnosis.

[Pathogenic roles of retinal glia in glaucoma]

Glaucoma, progressive optic neuropathy, is the first cause of blindness in Japan. Blindness in this disease is induced by damages or degeneration of retinal ganglion cells (RGCs), retinal neurons transmit visual information to brain. An elevated intraocular pressure (IOP) is widely recognized as one of the most important risk factors and that IOP directly damages RGCs by mechanical stress, however, accumulating evidences have shown that a majority of Japanese patients for primary open angle glaucoma shows normal level of IOP. Thus, new target for glaucoma pathology is emerged. In this issue, we introduce potential roles of glial cells for pathogenesis of glaucoma. In the CNS, reactive gliosis has been recognized in a variety of neurodegenerative diseases. Such glial activation is also found in retinae of human glaucoma patients and animal models. Importantly, glial activation precedes RGS degeneration, indicating the possibility that reactive glial cells actively contribute to pathogenesis of glaucoma. In this issue, we will focus on macroglial cells such as Muller cells and astrocytes, and discuss their roles in glaucoma.

Primary Open Angle Glaucoma and Vascular Risk Factors: A Review of Population Based Studies from 1990 to 2019

Glaucoma is one of the leading causes of blindness worldwide, and as the proportion of those over age 40 increases, so will the prevalence of glaucoma. The pathogenesis of primary open angle glaucoma (POAG) is unclear and multiple ocular risk factors have been proposed, including intraocular pressure, ocular perfusion pressure, ocular blood flow, myopia, central corneal thickness, and optic disc hemorrhages. The purpose of this review was to analyze the association between systemic vascular risk factors (including hypertension, diabetes, age, and migraine) and POAG, based on major epidemiological studies. Reports presenting the association between POAG and systemic vascular risk factors included a total of over 50,000 patients. Several epidemiological studies confirmed the importance of vascular risk factors, particularly hypertension and blood pressure dipping, in the pathogenesis and progression of glaucomatous optic neuropathy. We found that diabetes mellitus is associated with elevated intraocular pressure, but has no clear association with POAG. No significant correlation between migraine and POAG was found, however, the definition of migraine varied between studies.

Ocular conditions and dry eye due to traditional and new forms of smoking: A review

Addiction to cigarette smoking has high prevalence rates recorded worldwide. Smoking has been linked to several life-threatening systemic conditions such as cancer, heart attack and stroke, in addition to a range of ocular pathologies. In recent years, electronic cigarettes (EC) have emerged as alternatives to smoking. ECs are nicotine delivery devices which produce an aerosol by heating, rather than combusting, a liquid which contains nicotine, flavours and preservatives. This review focuses on the association of traditional and new forms of smoking with dry eye disease, contact lens wear and four other common ocular diseases: cataract, age-related macular degeneration, glaucoma and Graves' ophthalmopathy. It is concluded that smoking and vaping appear as a risk factor for the aforementioned ocular conditions. An evidence-based, clear link between cigarette smoking, or EC vaping and ocular problems is yet to be discovered.

Relationship of lifestyle, exercise, and nutrition with glaucoma

PURPOSE OF REVIEW

Although reducing the intraocular pressure (IOP) through medications, laser or surgery remains the primary means of glaucoma treatment, there is increasing evidence during the last decade that environmentally modifiable factors may help to prevent glaucoma or its progression through different mechanisms that may or may not involve lowering IOP. Additionally, patients are increasingly interested in maintaining a healthy lifestyle and taking an active role in the management of their disease. Therefore, the aim of this review is to summarize the current evidence regarding environmentally modifiable factors such as lifestyle, exercise, and nutrition in the pathogenesis of glaucoma.

RECENT FINDINGS

In the last decade, large population-based studies have helped to identify possible environmentally modifiable protective and risk factors with regard to glaucomatous disease. Smoking cessation; moderate aerobic exercise; recommended weight; and a balanced diet including green leafy vegetables, omega fatty-acids, and moderate intake of hot tea and coffee have been reported to be possibly protective against developing glaucoma or its progression.

SUMMARY

Modifiable environmental factors such as lifestyle, exercise, and nutrition may play a role in glaucoma pathogenesis. Large prospective studies with long-term follow-up should be encouraged to corroborate these findings, which may guide future treatments for our patients, some of which may not be limited to IOP reduction.