While several studies have revealed a relationship between smoking and age-related macular degeneration (AMD), a study in Mays British Journal of Ophthalmology reveals some definitive numbers regarding this link.

Specifically, current smokers are twice as likely to develop AMD than non-smokers. Approximately 28,000 cases of AMD in older people in the United Kingdom may be attributable to smoking, the researchers say.

Also, ex-smokers are at an intermediate risk for the condition, and those who quit smoking more than 20 years ago are not likely to develop AMD-causing visual loss, according to the population-based cross-sectional analytical study.

The study included 516 AMD patients 75 years and older who had relatively severe cases of AMD (visual acuity worse than 20/60), and 4,364 control subjects who had a binocular visual acuity of 20/20 or better. All participants came from 49 ophthalmological practices in the United Kingdom.

Researchers questioned participants to ascertain their smoking history. From there, data on smoking status, packs per year and the number of years since participants had quit smoking were assessed.

This study corroborates other studies demonstrating the significant risk smoking has in AMD, says optometrist Tracy Williams, executive director of the Deicke Center for Visual Rehabilitation in Wheaton, Ill. There is still much to be learned about AMD, and we as optometrists must continue to educate our patients about all the known risk factors for AMD, including smoking.
 
Evans JR, Fletcher AE, Wormald RP. 28,000 cases of age related macular degeneration causing visual loss in people aged 75 years and above in the United Kingdom may be attributable to smoking. Br J Ophthalmol 2005 May;89(5): 550-3.