Risk factors:-
1) Aging: Approximately 10% of patients 66 to 74 years of age will have findings of macular degeneration. The prevalence increases to 30% in patients 75 to 85 years of age.

2) Smoking: The only environmental exposure clearly associated with macular degeneration is tobacco smoking.

3) Family history: The lifetime risk of developing late-stage macular degeneration is 50% for people who have a relative with macular degeneration vs. 12% for people who do not have relatives with macular degeneration, i.e. a four fold higher risk.

4) Macular Degeneration Gene: Complement factor H (CFH) gene has been determined to be strongly associated with a person's risk for developing macular degeneration.

5) Exposure to sunlight especially blue light.

6) Hypertension. 

7) Cardiovascular Risk Factors - high cholesterol, obesity.

8) High fat intake is associated with an increased risk of macular degeneration in both women and men. Fat provides about 42 percent of the calories in the average American diet. A diet that derives closer to 20-25 percent of total calories from fat is probably healthier. Reducing fat intake to this level means cutting down greatly on consumption of red meats and dairy products such as milk, cheese, and butter. Eating more cold-water fish (at least twice weekly), rather than red meats and eating any type of nuts may help macular degeneration patients.(Reference: Macular degeneration Types and Risk Factors.

9) Oxidative stress: It has been proposed that age related accumulation of low molecular weight, phototoxic, pro-oxidant melanin oligomers within lysosomes in the retinal pigment epithelium (RPE) may be partly responsible for decreasing the digestive rate of photoreceptor outer rod segments (POS) by the RPE. A decrease in the digestive rate of POS has been shown to be associated with lipofuscin formation - a classic symptom of macular degeneration. (Reference: Ophthalmic Research, 2005; volume 37: pages 136-141. "Melanin aggregation and polymerization: possible implications in age related macular degeneration")

10) Race Macular degeneration is more likely to be found in whites than in blacks.

Signs:-

1) Drusen

2) Pigmentary alterations

3) Exudative changes: hemorrhages, hard exudates, subretinal/sub-RPE/intraretinal fluid

4) Atrophy: incipient and geographic

5) Visual acuity drastically decreasing (two levels or more) ex: 20/20 to 20/80.

6) Holes visible in fundus photographs.

Symptoms:-

1) Blurred vision: Those with nonexudative macular degeneration may by asymptomatic or notice a gradual loss of central vision, whereas those with exudative macular degeneration often notice a rapid onset of vision loss. 

2) Central scotomas

3) Distorted vision (i.e. metamorphopsia) - A grid of straight lines appears wavy and parts of the grid appear blank.

4) Trouble discerning colors; specifically dark ones from dark ones and light ones from light ones.

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