Table.

Comparison of Participants and Nonparticipants in AREDS Follow-up Study^a

	No. of Surviving AREDS Participants	AREDS Participants Active in the Follow-up Study, %	P Valueb
All	4203	84.4
AMD category
1	1031	88.5	<.001
2	960	85.8
3	1435	83.8
4	777	78.6
AREDS treatment assignment
Placebo	1312	83.8	.61
Antioxidants	1301	85.3
Zinc	806	83.5
Antioxidants plus zinc	784	84.9
Age, y
<65	957	90.4	<.001
65–69	1432	87.6
≥70	1814	78.8
Sex
Female	2412	84.2	.69
Male	1791	84.7
Educational levelc
High school or less	1460	80.7	<.001
Some college	1285	83.7
College graduate	1455	88.8
Race
Nonwhite	179	77.1	.006
White	4024	84.8
Smoking status
Never	1931	87.1	<.001
Former	1974	83.2
Current	298	75.5
BMId
<24.9	1369	85.1	.08
25.0–29.9	1761	85.2
≥30.0	1071	82.3
Hypertension
Normal	2611	86.6
Controlled	993	82.0	<.001
Uncontrolled and treated	280	76.8
Uncontrolled and untreated	319	81.5
Angina
No	3802	84.8	.07
Yes	401	81.3
Diabetes mellitus
No	3886	84.8	.007
Yes	317	81.3

Abbreviations: AMD, age-related macular degeneration; AREDS, Age-Related Eye Disease Study; BMI, body mass index (calculated as weight in kilograms divided by height in meters squared).

^aOf the original 4757 AREDS participants enrolled in the controlled clinical trial (1992–2001), 554 (11.6%) died at the end of the clinical trial, with 4203 surviving at the beginning of the follow-up study (October 1, 2001).

^bCalculated by the χ² test.

^cThree partipants were missing data.

^dTwo participants were missing data.