Page 5 - AMD AN OVERVIEW OF CLINICAL FORMS_Neat

Age-related macular degeneration: epidemiology, environmental and genetic risk factors

Age-related macular degeneration (AMD) is a common eye disease among older people, causing a
severe visual impairment. The pathophysiology of AMD remains largely unknown: it is a complex,
multi-factorial disease involving aging of the retina and a combination of environmental and
genetic factors.

1. Epidemiology

The majority of the large epidemiological studies on age-related macular degeneration (AMD) have been
conducted in the United States . The Beaver Dam Eye Study estimated the prevalence of advanced
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forms of the disease at 1.6% of the general population and 7.1% in people over 75 years old. In Europe,
the data from the EUREYE Study are consistent with the American data and indicate a prevalence of
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1.2% for geographic atrophy and 2.3% for exudative forms. In France, the disease affects an estimated
1.5 million people . It is estimated that by 2020, around 196 million people worldwide will be suffering
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from a form of AMD .
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2. Constitutional and environmental

risk factors

1) Constitutional factors

Several constitutional factors have been studied in order to identify their role in the onset of the disease.
Age is obviously a factor, with prevalence increasing with age. In addition, the prevalence of the disease
varies depending on the ethnic origin of the studied populations . Advanced forms of AMD are more
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common in Caucasian populations than in dark-skinned populations . In terms of sex, some meta-
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analyses have not found any differences in disease prevalence between men and women . However, the
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Beaver Dam Study found a higher incidence of age-related maculopathy in women over 75 compared
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to men of the same age.

Multiple studies have established correlations between certain cardiovascular risk factors and AMD. Klein
et al. found a correlation between patients with neovascular AMD and the presence of cardiovascular
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disease. Data from the AREDS study reveal increased cardiovascular mortality among patients with
AMD . However, other studies, such as AREDS Report No. 19, have not found any correlation between
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AMD and angina pectoris . High blood pressure has been studied independently. The results are similarly
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divergent, with some studies finding an association and others finding none .
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14 • AMD: AN OVERVIEW OF CLINICAL FORMS AMD: AN OVERVIEW OF CLINICAL FORMS • 15