Fine Particulate Matter and Age-Related Eye Disease: The Canadian Longitudinal Study on Aging

Abstract

Purpose To determine the relationship between fine particulate matter (PM 2.5 ) and ocular outcomes such as visual impairment and age-related eye disease. Methods Baseline data were used from the Canadian Longitudinal Study on Aging. The Comprehensive Cohort consisted of 30,097 adults ages 45 to 85 years. Annual mean PM 2.5 levels (µg/m 3 ) for each participant's postal code were estimated from satellite data. Ozone, sulfur dioxide, and nitrogen dioxide levels were also estimated. Binocular presenting visual acuity was measured using a visual acuity chart. Intraocular pressure (IOP) was measured in millimeters of mercury using the Reichart Ocular Response Analyzer. Participants were asked about a diagnosis of glaucoma, macular degeneration, or cataract. Logistic and linear regression models were used. Results The overall mean PM 2.5 level was 6.5 µg/m 3 (SD = 1.8). In the single pollutant models, increased PM 2.5 levels (per interquartile range) were associated with visual impairment (odds ratio [OR] = 1.12; 95% confidence interval [CI], 1.02–1.24), glaucoma (OR = 1.14; 95% CI, 1.01–1.29), and visually impairing age-related macular degeneration (OR = 1.52; 95% CI, 1.10–2.09) after adjustment for sociodemographics and disease. PM 2.5 had a borderline adjusted association with cataract (OR = 1.06; 95% CI, 0.99–1.14). In the multi-pollutant models, increased PM 2.5 was associated with glaucoma and IOP only after adjustment for sociodemographics and disease (OR = 1.24; 95% CI, 1.05–1.46 and β = 0.24; 95% CI, 0.12–0.37). Conclusions Increased PM 2.5 is associated with glaucoma and IOP. These associations should be confirmed using longitudinal data and potential mechanisms should be explored. If confirmed, this work may have relevance for revision of World Health Organization thresholds to protect human health.

Ambient Air Pollution and Age-Related Eye Disease: A Systematic Review and Meta-Analysis

“…There was no increased risk of cataract reported for those with greater exposure to PM 2.5 . Finally, Grant et al 24 reported a borderline association between PM 2.5 and cataract (OR = 1.06 per IQR; 95% CI, 0.99–1.14) in a single-pollutant model. However, they did not find an increased odds of cataract among those with greater exposure levels to PM 2.5 (OR = 0.98 per IQR; 95% CI, 0.90–1.07) in the multipollutant model.…”

“…Chua et al 22 did not present a multipollutant model. Third, Grant et al 24 reported that those who lived in areas with higher PM 2.5 levels were more likely to have visually impairing AMD (OR = 1.51 per IQR; 95% CI, 1.10–2.08) in a single–pollutant model. However, in a multipollutant model, they found a borderline association between exposure to PM 2.5 and visually impairing AMD (OR = 1.41 per IQR; 95% CI, 0.96–2.08).…”

“…Three studies 4 , 21 , 25 were considered to have a low risk of bias (total score ≥7) based on the Newcastle–Ottawa scale adapted for nonrandomized studies. Five studies 3 , 5 , 22 – 24 were considered to have a medium risk of bias (total score <7) due to low response rates, 3 , 22 , 24 low representativeness, 5 imprecise ascertainment of exposure, 5 and a lack of adjustment in analyses for lifestyle factors such as smoking status. 23 Cohen's κ was 0.75, indicating good interrater agreement.…”

“…Three studies reported on the outcome of AMD. 5 , 22 , 24 First, single-pollutant model findings from Chang et al 5 suggest that there is an increased risk of AMD among those exposed to higher levels of both CO (HR = 1.84 for the highest quartile; 95% CI, 1.57–2.15) and NO 2 (HR = 1.91 for the highest quartile; 95% CI, 1.64–2.23). There was no increased risk for the second or third quartiles, indicating a threshold rather than a dose–response effect.…”

“…Three studies reported on the outcome of cataracts. 4 , 21 , 24 First, results from Choi et al 21 found that there was no statistically significant association between PM 10 , NO 2 , or SO 2 exposure and any cataract in single- or multipollutant models. However, the results for NO 2 differed by cataract subtype.…”