Smoking can increase chances of blindness, finds EU study
A recently completed EU funded project is to publish strong evidence of a link between smoking and blindness. The findings highlight the need for increasing public awareness of the risks associated with smoking, and the benefits of kicking the habit. The EUREYE study received 2.4 million euro under the 'Quality of Life and Management of Living Resources' section of the Fifth Framework Programme (FP5). The team examined the relationship in Europe between cigarette smoking and age-related macular degeneration (AMD) - a disease that affects the macula part of the eye, resulting in a blurring of the central vision. There are two main types of AMD disease, namely 'wet' AMD, which occurs when abnormal blood vessels behind the retina start to grow under the macula, often leaking blood and fluid; and 'dry' AMD, which is when the light-sensitive cells in the macula slowly break down, gradually blurring the central vision in the affected eye. AMD is considered to be the most important cause of adult blindness in developed countries, occurring predominantly in the older population, especially in those aged over 70 years. For the purpose of the study, researchers from centres in Estonia, France, Greece, Italy, the Netherlands, Spain, United Kingdom (UK) and Norway randomly sampled over 5,000 patients aged 65 and over who were categorised as non-smokers, current smokers, and ex-smokers - the latter were further divided based on how long ago they had given up smoking. Patients were also examined for the prevalence of the AMD disease. The study took into account confounding variables such as age, sex, diabetes, socio-economic status and history of cardiovascular disease. Based on the data, the researchers were able to observe consistent relationships between a history of smoking and different levels in the severity of the eye disease. For example, in the case of ex-smokers, researchers noticed that incidences and the severity of the eye disease decreased over time, especially for those who gave up smoking over 20 years previously. Overall, the study found that 27 per cent of the total patients had AMD eye disease that could be directly attributable to smoking, and estimated that one in four cases of 'wet' AMD and a third of cases of 'dry' MAD could be prevented by not smoking. 'The study is the biggest and most comprehensive European study of its kind which makes it much more applicable to the European population,' Astrid Fletcher, project coordinator, told CORDIS News. 'While previous population-based studies have examined associations between smoking and severe cases of the AMD eye disease, to our knowledge the EUREYE study is the first to report on the risk for patients who already have the disease in one eye, of contracting it in the other if they continue to smoke,' she said. On a positive note, the findings suggest that the adverse effects of smoking can be reduced if a decision is taken early enough to kick the habit. These findings, Ms Fletcher says, clearly highlight the need for greater public awareness about the risks of smoking The findings are part of a wider mandate by the partners of the EUREYE project to examine environmental determinants of macular degeneration in the European population. The project included research which found that high levels of sunlight can increase the risk of the AMD disease if the levels of anti-oxidants in the body are low. Partners in the project also analysed the relationship between fatty acids and the eye disease, finding that while high intakes of essential fatty acids are highly protective against AMD, saturated acids could increase the risk.
Countries
Estonia, Greece, Spain, France, Italy, Netherlands, Norway, United Kingdom