Aetiology

Aetiology of AMD is unknown but it is considered as a multifactorial disease. Several risk factors of macular degeneration have been recognised (1):

• age:
  • most people presenting with macular degeneration are over 60 years of age
    
    
• presence of precursor lesions e.g. – large drusen, soft indistinct drusen (2)
• cigarette smoking
  • is a well known risk factor for the development of AMD
  • the risk is two to three-fold higher in current smokers and the risk also increases with the number of pack-years
  • people with a genetic susceptibility have a greater chance of developing AMD if they smoke (1)
    
    
• race, usually Caucasian (3)
  
  
• female sex (2)
  
  
• hypertension (7)
  
  
• BMI of 30 kg/m2 or higher (7)
  
  
• diet low in omega 3 and 6, vitamins, carotenoid and minerals (7)
  
  
• diet high in fat (6,7)
  
  
• lack of exercise (7)
  
  
• presence of AMD in the other eye (7)
  
  
• hereditary:
  • first degree relatives of patients with AMD are at an increased risk of acquiring the condition, specially at a younger age (4)
  • degenerative changes during childhood or adolescence tend to have genetic explanations e.g. Tay-Sachs disease
    
    
• drug induced:
  • chloroquine and derivative drugs

There is an association with atheroma and dyslipidaemias (1).

Diet and risk of age related macular degeneration (AMD)

• a diet low in trans-unsaturated fat and rich in omega-3 fatty acids and olive oil may reduce the risk of AMD (2)

Reference:

• (1) Chopdar A, Chakravarthy U, Verma D. Age related macular degeneration. BMJ. 2003;326(7387):485-8
• (2) The Royal College of Ophthalmologists 2009. Age related macular degeneration: Guidelines for management
• (3) Coleman HR et al. Age-related macular degeneration. Lancet. 2008; 372(9652): 1835–1845
• (4) de Jong PT. Age-related macular degeneration. N Engl J Med. 2006;355(14):1474-85
• (5) Pulse (1/9/01), 12.
• (6) Feigin VL et al.Fat consumption and its association with age-related macular degeneration. Lancet Neurol. 2009 Apr;8(4):355-6
• (7) NICE (January 2018). Age-related macular degeneration