Table 4. Prevalence and adjusted odds ratio of early type of age-related macular degeneration (AMD), stratified according to quintile category of blood lead among representative Korean adults aged 40 years or older included in the study.

Prevalence is expressed as weighted estimate [%] (95% confidence intervals, standard errors [%]).

Blood lead quintiles (μg/dL)	Unweighted number	Prevalence	Model 1	Model 2
Both genders
Quintile 1 (<1.75)	994	4.0 (2.9–5.5, 0.7)	1.00 (reference)	1.00 (reference)
Quintile 2 (1.75–2.25)	986	3.8 (2.8–5.3, 0.6)	0.95 (0.59–1.54)	1.04 (0.62–1.73)
Quintile 3 (2.25–2.73)	978	4.5 (3.3–6.2, 0.7)	1.13 (0.72–1.78)	1.14 (0.70–1.84)
Quintile 4 (2.73–3.38)	987	4.8 (3.6–6.4, 0.7)	1.20 (0.77–1.86)	1.26 (0.78–2.06)
Quintile 5 (>3.38)	988	5.7 (4.3–7.5, 0.8)	1.44 (0.94–2.22)	1.55 (0.94–2.53)
P for trend		.341	.067	.052
Men
Quintile 1 (<2.14)	485	3.6 (2.3–5.8, 0.9)	1.00 (reference)	1.00 (reference)
Quintile 2 (2.14–2.64)	493	2.3 (1.2–4.2, 0.7)	0.62 (0.29–1.31)	0.66 (0.31–1.40)
Quintile 3 (2.64–3.12)	488	5.0 (3.3–7.3, 1.0)	1.38 (0.73–2.61)	1.32 (0.68–2.56)
Quintile 4 (3.12–3.79)	485	3.2 (2.0–5.1, 0.8)	0.88 (0.44–1.73)	0.80 (0.40–1.60)
Quintile 5 (>3.79)	495	5.8 (4.0–8.5, 1.1)	1.64 (0.86–3.13)	1.32 (0.68–2.54)
P for trend		.044*	.090	.248
Women
Quintile 1 (<1.53)	499	2.9 (1.9–4.6, 0.7)	1.00 (reference)	1.00 (reference)
Quintile 2 (1.53–1.94)	504	5.6 (3.7–8.3, 1.1)	1.94 (1.02–3.69)*	1.72 (0.86–3.46)
Quintile 3 (1.94–2.34)	489	6.0 (3.8–9.4, 1.4)	2.11 (1.08–4.10)*	1.83 (0.90–3.73)
Quintile 4 (2.34–2.87)	500	5.5 (3.5–8.6, 1.3)	1.92 (1.00–3.70)*	1.41 (0.72–2.77)
Quintile 5 (>2.87)	495	6.9 (4.8–9.7, 1.2)	2.42 (1.39–4.22)*	1.92 (1.06–3.48)*
P for trend		.120	.010*	.159

Odds Ratios (OR) reflects the risk of AMD in given quintile versus the risk in the lowest quintile.

Model 1: Crude OR. Model 2: adjusted for sex, age, smoking, total cholesterol level, triglyceride level, hypertension, heart problem, and stroke.

*P < 0.05