Cited by 390Retinal Diseases and TreatmentsRetinal Imaging and AnalysisSmoking Behavior and Cessation

Smoking and age related macular degeneration: the number of pack years of cigarette smoking is a major determinant of risk for both geographic atrophy and choroidal neovascularisation

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Khan, J C·2006·British Journal of Ophthalmology

Abstract

BACKGROUND/AIMS: There is evidence that smoking is a risk factor for age related macular degeneration (AMD). However, not all studies have demonstrated this association and several key questions about the role of smoking in AMD have still to be determined. The aim of this study was to further investigate this relation for both choroidal neovascularisation (CNV) and geographic atrophy (GA). METHODS: To investigate the relation between smoking and the risk of developing age related macular degeneration (AMD) in white people, 435 cases with end stage AMD were compared with 280 controls. All subjects had graded stereoscopic colour fundus photography and AMD was defined as the presence of GA or CNV. Smoking history was assessed using multiple parameters in a detailed questionnaire. RESULTS: Comparison of current and former smokers with non-smokers was consistent with smoking being a risk factor for AMD but did not reach statistical significance. There was a strong association between AMD and pack years of cigarette smoking (p = 0.002), the odds ratio increasing with the amount smoked; for subjects with more than 40 pack years of smoking the odds ratio was 2.75 (95% CI 1.22 to 6.20) compared with non-smokers. Both types of AMD showed a similar relation; smoking more than 40 pack years of cigarettes was associated with an odds ratio of 3.43 (95% CI 1.28 to 9.20) for GA and 2.49 (95% CI 1.06 to 5.82) for CNV. Stopping smoking was associated with reduced odds of AMD and the risk in those who had not smoked for over 20 years was comparable to non-smokers. The risk profile was similar for males and females. Passive smoking exposure was associated with an increased risk of AMD (OR 1.87; 95% CI 1.03 to 3.40) in non-smokers. CONCLUSIONS: The authors have demonstrated a strong association between the risk of both GA and CNV and pack years of cigarette smoking. This provides support for a causal relation between smoking and AMD. They also show an increased risk for AMD in non-smokers exposed to passive smoking. Stopping smoking appears to reduce the risk of developing AMD.

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Authors
Khan, J. C.
Affiliations
University of Cambridge (GB)
Corresponding author
Khan, J C
Venue
British Journal of Ophthalmology
Publisher
BMJ
Published
2006-01-01
Volume
90
Issue
1
Pages
75-80
ISSN
0007-1161 (ISSN-L)
OpenAlex
W1990289864
Cited by
390
References
51
Citations by year
2026: 26 · 2025: 9 · 2024: 11 · 2023: 11 · 2022: 13 · 2021: 17 · 2020: 17 · 2019: 20 · 2018: 16 · 2017: 28 · 2016: 16 · 2015: 28 · 2014: 15 · 2013: 28 · 2012: 17
FWCI
14.98
Type
journal article
Language
en
Open access
Locations
  • British Journal of Ophthalmology (publishedVersion)
  • PubMed Central (publishedVersion)
  • PubMed (publishedVersion)
Funders
Moorfields Eye Hospital NHS Foundation Trust
Topics
  • Health Sciences › Medicine › Ophthalmology › Retinal Diseases and Treatments
  • Health Sciences › Medicine › Radiology, Nuclear Medicine and Imaging › Retinal Imaging and Analysis
  • Health Sciences › Medicine › Physiology › Smoking Behavior and Cessation
Keywords
age-related macular degeneration, smoking, pack-years, geographic atrophy, choroidal neovascularization, passive smoking, smoking cessation, risk factors
MeSH terms
Aged, Aged, 80 and over, Atrophy, Female, Humans, Macular Degeneration, Male, Pigment Epithelium of Eye, Risk Factors, Smoking, Time Factors, Tobacco Smoke Pollution, Case-Control Studies, Smoking Cessation, Choroidal Neovascularization

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