The association between cigarette smoking and ocular diseases
ACK Cheng, CP Pang, ATS Leung, JKH Chua, DSP Fan, DSC Lam
Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong
OBJECTIVE. To review the effect of smoking on common ocular disorders.
DATA SOURCES. Medline literature search, 1966 to 1999.
STUDY SELECTION. The following key words were used: smoking; Graves' disease, age-related macular degeneration; glaucoma; cataract.
DATA EXTRACTION. Epidemiological and experimental studies were reviewed.
DATA SYNTHESIS. Cigarette smoking is an important risk factor for cardiovascular, respiratory, and malignant diseases. There is also a strong association between smoking and a number of common eye diseases, which include Graves' ophthalmopathy, age-related macular degeneration, glaucoma, and cataract. Despite the multifactorial aetiology of these ocular syndromes, smoking is an independent risk factor that has dose-response effects. It causes morphological and functional changes to the lens and retina due to its atherosclerotic and thrombotic effects on the ocular capillaries. Smoking also enhances the generation of free radicals and decreases the levels of antioxidants in the blood circulation, aqueous humour, and ocular tissue. Thus, the eyes are more at risk of having free-radical and oxidation attacks in smokers.
CONCLUSION. Smoking, if continued, may perpetuate further ocular damage and lead to permanent blindness. Cessation of smoking and avoidance of passive smoking is advised to minimise the harmful effects of smoking on the eyes.
Hong Kong Med J 2000;6:195-202
Key words: Eye diseases/prevention & control; Eye diseases/epidemiology; Risk factors; Smoking/adverse effects